The whisky and water trick

I don't know if the nudie playing cards are absolutely essential, but this trick is pretty neat.

(via @itscolossal)

A Brief History of Time by Errol Morris

The sound and picture are poor, but the entirety of Errol Morris' A Brief History of Time is available on YouTube.

Featuring music from Philip Glass, the film is a documentary about Stephen Hawking and his ideas about the universe. Morris recently stated on Twitter:

Yes. I plan to re-release [A Brief History of Time]. (It was never properly color corrected and is one of my best films.)

The film is difficult, if not impossible, to find on DVD and isn't available on Netflix, Amazon Instant Video, or iTunes. And as far as I can tell, the soundtrack was never released either.

Slow motion magnets

If you drop a bunch of neodymium magnets down through a thick-walled copper pipe, an effect called eddy current braking will slow the magnets' fall even though there's no direct magnetic attraction between the copper and the magnets.

Science! (via make)

Camera shooting at a trillion frames/sec can see photons move

At the beginning of this video, Ramesh Raskar, associate professor at the MIT Media Lab, announces calmly:

We have built a virtual slow-motion camera where we can see photons, or light particles, moving through space.

Yeah, no biggie.

Higgs boson found?

Rumor has it that the LHC at CERN has found the Higgs boson. The news runs contrary to some earlier speculation.

The teams are sworn to secrecy, but various physics blogs, and the canteens at Cern, are alive with talk of a possible sighting of the Higgs, and with a mass inline with what many physicists would expect.

Since the Higgs' nickname is the God particle, does this count as the Second Coming? (@gavinpurcell)

Ten things everyone should know about time

From Sean Carroll at Cosmic Variance, a list of facts and very strong opinions about the nature of time.

4. You live in the past. About 80 milliseconds in the past, to be precise. Use one hand to touch your nose, and the other to touch one of your feet, at exactly the same time. You will experience them as simultaneous acts. But that's mysterious - clearly it takes more time for the signal to travel up your nerves from your feet to your brain than from your nose. The reconciliation is simple: our conscious experience takes time to assemble, and your brain waits for all the relevant input before it experiences the "now." Experiments have shown that the lag between things happening and us experiencing them is about 80 milliseconds.

5. Your memory isn't as good as you think. When you remember an event in the past, your brain uses a very similar technique to imagining the future. The process is less like "replaying a video" than "putting on a play from a script." If the script is wrong for whatever reason, you can have a false memory that is just as vivid as a true one. Eyewitness testimony, it turns out, is one of the least reliable forms of evidence allowed into courtrooms.

NYC water towers

One of the many reasons to love the wooden water towers found on the tops of NYC buildings is that the structures themselves reveal the math behind how they work.

The distance between the metal bands holding the cylindrical structure together decreases from top to bottom because the pressure the water exerts increases with depth. The top band only needs to fight against the water at the very top of the tower but the bottom bands have to hold the entire volume from bursting out.

Quantum levitation!

What the what? This video gives a little more explanation into the effect at work here (superconductivity + quantum trapping of the magnetic field in quantum flux tubes) and an awesome demonstration of a crude rail system. You can almost hear your tiny mind explode when the "train" goes upside-down.

Wingardium Leviosa! (via stellar)

The physics of the riderless bike

Why do riderless bicycles not fall over? Science Friday looks at the science behind bike self-steering.

(via robottke!)

That's faster than the speed of light, you idiot!

Physicists at CERN believe they have observed neutrinos moving at speeds faster than the speed of light, a feat previously assumed to be impossible.

Thousands of experiments have been undertaken to measure it ever more precisely, and no result has ever spotted a particle breaking the limit.

But Dr Ereditato and his colleagues have been carrying out an experiment for the last three years that seems to suggest neutrinos have done just that.

Neutrinos come in a number of types, and have recently been seen to switch spontaneously from one type to another.

The team prepares a beam of just one type, muon neutrinos, sending them from Cern to an underground laboratory at Gran Sasso in Italy to see how many show up as a different type, tau neutrinos.

In the course of doing the experiments, the researchers noticed that the particles showed up 60 billionths of a second sooner than light would over the same distance.

This is a tiny fractional change, but one that occurs consistently.

The team measured the travel times of neutrino bunches some 15,000 times, and have reached a level of statistical significance that in scientific circles would count as a formal discovery.

If true, saying this is a significant discovery is a doubly significant understatement.

Not looking good for the Higgs boson

Most of the possible masses for the Higgs boson (aka the God particle) have been eliminated with at a 95% confidence level by physicists at CERN. They're checking the other masses and will likely have an answer one way or the other in December.

"We are now entering a very exciting phase in the hunt for the Higgs boson," Sharma said. "If the Higgs boson exists between 114-145 GeV, we should start seeing statistically significant excesses over estimated backgrounds, and if it does not then we hope to rule it out over the entire mass range. One way or the other we are poised for a major discovery, likely by the end of this year."

(via @daveg)

Freeman, Feynman, and Hawking, autotuned

The giants of physics (and Morgan Freeman, who can be a giant of anything he wants) explain quantum mechanics using relatively simple terms and autotune.

(via devour)

Pendulum waves

Mesmerizing video of a series of pendulums moving in an out of sync with each other until at the end...well, I won't spoil it.

(thx, john)

Einstein was right. Again.

NASA's just finished an impressive experiment designed to test Einstein's general theory of relativity -- specifically the "mass distorts spacetime" part:

Put a spinning gyroscope into orbit around the Earth, with the spin axis pointed toward some distant star as a fixed reference point. Free from external forces, the gyroscope's axis should continue pointing at the star--forever. But if space is twisted, the direction of the gyroscope's axis should drift over time. By noting this change in direction relative to the star, the twists of space-time could be measured.

Gravity Probe B's experiment was 47 years in the making, helped spawn 100 PhD theses, and required the invention of 13 brand-new technologies, including a "drag-free satellite." The four gyroscopes in GP-B are "the most perfect spheres ever made by humans... If the gyroscopes weren't so spherical, their spin axes would wobble even without the effects of relativity."

NASA finished collecting the data in 2005; now they've crunched the numbers. And yes, Einstein was right. The gyroscopes wobble in just the way general relativity predicts.

The first and most famous empirical experiment testing Einstein's theory was performed in 1919 by Arthur Eddington during a full solar eclipse. Photographs showed that the sun's mass caused starlight to bend around it.

(Image by James Overduin, Pancho Eekels, and Bob Kahn via NASA.)

New particle or just bad data?

Scientists at Fermilab have found a "suspicious bump" in their data from the Tevatron that may indicate the discovery of a new particle (not the Higgs boson) or a new force of nature or a mistake.

"Nobody knows what this is," said Christopher Hill, a theorist at Fermilab who was not part of the team. "If it is real, it would be the most significant discovery in physics in half a century."

We won't have to wait too long to see if the bump is real...the LHC will reveal all soon.

All about nuclear meltdowns

I haven't been keeping up with the Japan nuclear power plant situation as much as I want, but I wanted to pass along a few interesting articles. Over at Boing Boing, Maggie Koerth-Baker wrote a widely linked piece about how nuclear power plants work:

For the vast majority of people, nuclear power is a black box technology. Radioactive stuff goes in. Electricity (and nuclear waste) comes out. Somewhere in there, we're aware that explosions and meltdowns can happen. Ninety-nine percent of the time, that set of information is enough to get by on. But, then, an emergency like this happens and, suddenly, keeping up-to-date on the news feels like you've walked in on the middle of a movie. Nobody pauses to catch you up on all the stuff you missed.

As I write this, it's still not clear how bad, or how big, the problems at the Fukushima Daiichi power plant will be. I don't know enough to speculate on that. I'm not sure anyone does. But I can give you a clearer picture of what's inside the black box. That way, whatever happens at Fukushima, you'll understand why it's happening, and what it means.

MrReid, a physics teacher, writes about the situation at Fukushima:

Even with the release of steam, the pressure and temperature inside Unit 1 continued to increase. The high temperatures inside the reactor caused the protective zirconium cladding on the uranium fuel rods to react with steam inside the reactor to form zirconium oxide and hydrogen. This hydrogen leaked into the building that surrounded the reactor and ignited, damaging the surrounding building but without damaging the reactor vessel itself. Because the reactor vessel has not been compromised, the release of radiation should be minimal. It appears that a very similar situation has occurred at Unit 3 and that hydrogen is again responsible for the explosion seen there.

And this piece is a more meta take on the situation, What the Media Doesn't Get About Meltdowns.

Of immediate concern is the prospect of a so-called "meltdown" at one or more of the Japanese reactors. But part of the problem in understanding the potential dangers is continued indiscriminate use, by experts and the media, of this inherently frightening term without explanation or perspective. There are varying degrees of melting or meltdown of the nuclear fuel rods in a given reactor; but there are also multiple safety systems, or containment barriers, in a given plant's design that are intended to keep radioactive materials from escaping into the general environment in the event of a partial or complete meltdown of the reactor core. Finally, there are the steps taken by a plant's operators to try to bring the nuclear emergency under control before these containment barriers are breached.

A short history of the Earth

From physicist John Baez, a history of the major disasters that happened to the Earth: the Big Splat, the Late Heavy Bombardment, the Oxygen Catastrophe, and the Snowball Earth. The Big Splat is believed to have formed the Moon:

In 2004, the astrophysicist Robin Canup, at the Southwest Research Institute in Texas, published some remarkable computer simulations of the Big Splat. To get a moon like ours to form -- instead of one too rich in iron, or too small, or wrong in other respects -- she had to choose the right initial conditions. She found it best to assume Theia is slightly more massive than Mars: between 10% and 15% of the Earth's mass. It should also start out moving slowly towards the Earth, and strike the Earth at a glancing angle.

The result is a very bad day. Theia hits the Earth and shears off a large chunk, forming a trail of shattered, molten or vaporized rock that arcs off into space. Within an hour, half the Earth's surface is red-hot, and the trail of debris stretches almost 4 Earth radii into space. After 3 to 5 hours, the iron core of Theia and most of the the debris comes crashing back down. The Earth's entire crust and outer mantle melts. At this point, a quarter of Theia has actually vaporized!

After a day, the material that has not fallen back down has formed a ring of debris orbiting the Earth. But such a ring would not be stable: within a century, it would collect to form the Moon we know and love. Meanwhile, Theia's iron core would sink down to the center of the Earth.

How much is a planet worth?

Over at Boing Boing, Lee Billings has an interview with Greg Laughlin, an astrophysicist who recently came up with an equation for estimating the value of planets, a sort of Drake equation for cosmic economics.

This equation's initial purpose, he wrote, was to put meaningful prices on the terrestrial exoplanets that Kepler was bound to discover. But he soon found it could be used equally well to place any planet-even our own-in a context that was simultaneously cosmic and commercial. In essence, you feed Laughlin's equation some key parameters -- a planet's mass, its estimated temperature, and the age, type, and apparent brightness of its star -- and out pops a number that should, Laughlin says, equate to cold, hard cash.

At the time, the exoplanet Gliese 581 c was thought to be the most Earth-like world known beyond our solar system. The equation said it was worth a measly $160. Mars fared better, priced at $14,000. And Earth? Our planet's value emerged as nearly 5 quadrillion dollars. That's about 100 times Earth's yearly GDP, and perhaps, Laughlin thought, not a bad ballpark estimate for the total economic value of our world and the technological civilization it supports.

Best science of 2010

Science magazine has named their top scientific breakthroughs of 2010 and the insights of the decade. The quantum paddle deservedly took the top spot:

"This year's Breakthrough of the Year represents the first time that scientists have demonstrated quantum effects in the motion of a human-made object," said Adrian Cho, a news writer for Science. "On a conceptual level that's cool because it extends quantum mechanics into a whole new realm. On a practical level, it opens up a variety of possibilities ranging from new experiments that meld quantum control over light, electrical currents and motion to, perhaps someday, tests of the bounds of quantum mechanics and our sense of reality."

Evidence of other universes

Cosmologists have discovered evidence that our universe has been "bruised" by collisions with other universes.

Today, another group says they've found something else in the echo of the Big Bang. These guys start with a different model of the universe called eternal inflation. In this way of thinking, the universe we see is merely a bubble in a much larger cosmos. This cosmos is filled with other bubbles, all of which are other universes where the laws of physics may be dramatically different to ours.

The findings are currently difficult to reproduce, but with better data on the way, scientists are hoping to get to the bottom of the matter in the next few years.

Liquid magic

Under certain circumstances, you can mix liquids of different colors, then unmix them, and not violate the second law of thermodynamics.

(via fine structure)

LHC generates a mini Big Bang

By smashing together lead ions instead of protons, researchers at the Large Hadron Collider have produced a "mini-Big Bang".

The collisions obtained were able to generate the highest temperatures and densities ever produced in an experiment. "This process took place in a safe, controlled environment, generating incredibly hot and dense sub-atomic fireballs with temperatures of over ten trillion degrees, a million times hotter than the centre of the Sun.

"At these temperatures even protons and neutrons, which make up the nuclei of atoms, melt resulting in a hot dense soup of quarks and gluons known as a quark-gluon plasma." Quarks and gluons are sub-atomic particles -- some of the building blocks of matter. In the state known as quark-gluon plasma, they are freed of their attraction to one another. This plasma is believed to have existed just after the Big Bang.

Seawater antennas

The US Navy is looking for a way to replace bulky antennas on warships with antennas made from seawater.

What they came up with is little more than an electromagnetic ring and a water pump. The ring, called a current probe, creates a magnetic field through which the pump shoots a steam of seawater (the salt is a key ingredient, as the tech relies on the magnetic induction properties of sodium chloride). By controlling the height and width of the, the operator can manipulate the frequency at which the antenna transmits and receives. An 80-foot-high stream can transmit and receive anywhere from 2 to 400 mHz, though much smaller streams can be used for varying other frequencies, ranging from HF through VHF to UHF.

Wow. (via bldgblog)

The physics of everyday life

Christoph Niemann hits another one out of the park with an illustrated look at the how physics governs everything we do in life.

I loved his idea for calorie-neutral foods:

All you need is to freeze a pint of ice cream to -3706 F. The energy it will take your system to bring the ice cream up to a digestible temperature is roughly 1,000 calories, neatly burning away all those carbohydrates from the fat and sugar. The only snag is the Third Law of Thermodynamics, which says it's impossible to go below -459 F. Bummer.

Finding the resolution of the universe

Researchers at Fermilab are building a holometer, the most precise clock ever, which will attempt to determine if the 3-D aspect of the universe is a hologram.

Black hole physics, in which space and time become compressed, provides a basis for math showing that the third dimension may not exist at all. In this two-dimensional cartoon of a universe, what we perceive as a third dimension would actually be a projection of time intertwined with depth. If this is true, the illusion can only be maintained until equipment becomes sensitive enough to find its limits. "You can't perceive it because nothing ever travels faster than light," says Hogan. "This holographic view is how the universe would look if you sat on a photon."

The Great Egg Race

The Great Egg Race was a late-70s/early-80s BBC TV show that was a kind of Junkyard Wars on a smaller and more nerdy scale. The first episode shows a number of people attempting to build small egg carrying cars powered by rubber band.

I love this stuff. I had a physics teacher in high school who presented us with a number of these challenges throughout the school year. There was the strong toothpick bridge (someone basically cheated and made a glue bridge with embedded toothpicks) and the rolling object (it had to go down a short ramp and stop on a mark about 10 feet away), but my favorites were the mouse trap-powered car and the egg drop.

The winning mouse trap car was made with a lot of assistance from the student's father, who owned a machine shop. It was light but solid with precisely machined plastic wheels and a precisely machined axle and travelled probably twice as far as any of the other cars, which were generally built with whatever crappy off-the-shelf components could be scrounged from the local five-and-dime. I spent three satisfying late nights building my car and came in pretty close to last.

The egg drop challenge involved constructing a landing pad no taller than 12 inches for an unboiled egg. Competitors dropped their eggs from successively greater heights until the egg broke. The two winning landing pads were successful at the greatest height that our small school could muster...out a window at the top of the football field stands, probably about 35 or 40 feet tall. One was a huge box full of wool and other soft materials that could have successfully cushioned an egg dropped from the top of the Sears Tower. The other winner was a tupperware bowl full of stale popcorn that your humble blogger grabbed off the counter the morning of the challenge after completely forgetting about it over the weekend. No one was more surprised than I to discover that popcorn is an ideal egg cushioning material...not that I let on. :)

Lots of big machines to make a tiny Sun

The Big Picture has a selection of photos of the National Ignition Facility which I've written about previously.

"Creating a miniature star on Earth" is the goal of the National Ignition Facility (NIF), home to the world's largest and highest-energy laser in Livermore, California. On September 29th, 2010, the NIF completed its first integrated ignition experiment, where it focused its 192 lasers on a small cylinder housing a tiny frozen capsule containing hydrogen fuel, briefly bombarding it with 1 megajoule of laser energy. The experiment was the latest in a series of tests leading to a hoped-for "ignition", where the nuclei of the atoms of the fuel inside the target capsule are made to fuse together releasing tremendous energy -- potentially more energy than was put in to start the initial reaction, becoming a valuable power source.

The NIF and the LHC are this generation's Apollo program.

Gliese 581g, we hardly knew ye

That habitable exoplanet discovery? Maybe not.

Astronomer Francesco Pepe of the Geneva Observatory in Switzerland, who spoke Oct. 11 at an International Astronomical Union symposium on planetary systems, reported a new analysis using only HARPS data, but adding an extra 60 data points to the observations published in 2008. He and his colleagues could find no trace of the planet.

The physics of Angry Birds

Using motion tracking software, Rhett Allain finds out if the flight of the slingshotted Angry Birds adheres to the laws of physics.

The only force acting on the bird (if the bird is not moving too fast) would be the gravitational force from the Earth. This is where I see lots of intro-student mistakes. They tend to want to put some force in the horizontal direction because the bird is moving that way. DON'T do that. That is what Aristotle would have you believe, but you don't want to be in his club. There is no horizontal force in this case -- no air resistance.

He also determines the height of the red bird: about 2.3 feet tall. The big red bird must be at least double that.

Potential Earth-like exoplanet discovered

A team of scientists has discovered a potentially habitable planet located about 20 light years from Earth.

The paper reports the discovery of two new planets around the nearby red dwarf star Gliese 581. This brings the total number of known planets around this star to six, the most yet discovered in a planetary system other than our own solar system. Like our solar system, the planets around Gliese 581 have nearly circular orbits.

The most interesting of the two new planets is Gliese 581g, with a mass three to four times that of the Earth and an orbital period of just under 37 days. Its mass indicates that it is probably a rocky planet with a definite surface and that it has enough gravity to hold on to an atmosphere, according to Vogt.

Gliese 581, located 20 light years away from Earth in the constellation Libra, has a somewhat checkered history of habitable-planet claims. Two previously detected planets in the system lie at the edges of the habitable zone, one on the hot side (planet c) and one on the cold side (planet d). While some astronomers still think planet d may be habitable if it has a thick atmosphere with a strong greenhouse effect to warm it up, others are skeptical. The newly discovered planet g, however, lies right in the middle of the habitable zone.

Sam Arbesman's prediction of May 2011 might have been too conservative. And 20 light years...that means we could send a signal there, and if someone of sufficient technological capability is there and listening, we could hear something back within our lifetime. Contact! (thx, jimray)

Putting your hand in the Large Hadron Collider

Several physicists weigh in on what would happen if you were to place your hand in the proton stream of the Large Hadron Collider at CERN.

There's not a definite answer...the responses range from "nothing" to "you'd die for sure, instantly".

Bouncing baby bombs

This little guy is a newborn uncontrolled nuclear fisson reaction. You know, an atomic bomb.

This is from a NY Times photo slideshow of atomic bomb explosions. Check out the school bus sequence starting at slide #14.

When will the first Earth-like planet be discovered?

Using the properties of previously discovered exoplanets (that is, planets outside of our solar system) and their dates of discovery, Sam Arbesman and Greg Laughlin predict that the discovery of the first Earth-like exoplanet will likely occur in early May 2011.

Of course, it's a bit more complicated than that, but here's an overview of what we did. Using the properties of previously discovered exoplanets, we developed a simple metric of habitability for each planet that uses its mass and temperature to rate it on a scale of 0 to 1, where 1 is Earth-like, and 0 is so very not Earth-like. Plotting these values over time and taking the upper envelope yields a nice march towards habitability.

The authors don't address this directly in their paper, but I wondered what the Moore's Law for planetary discovery might be -- e.g. every X years (or months?), the habitability of the most habitable planet discovered doubles. So I emailed Sam Arbesman and he said that his quick back of the envelope calculation would be "half a month or so"...which is an astounding pace.

The Grand Design

Stephen Hawking's new book is out: The Grand Design, sequel to A Brief History of Time written with Leonard Mlodinow.

In The Grand Design we explain why, according to quantum theory, the cosmos does not have just a single existence, or history, but rather that every possible history of the universe exists simultaneously. We question the conventional concept of reality, posing instead a "model-dependent" theory of reality. We discuss how the laws of our particular universe are extraordinarily finely tuned so as to allow for our existence, and show why quantum theory predicts the multiverse--the idea that ours is just one of many universes that appeared spontaneously out of nothing, each with different laws of nature. And we assess M-Theory, an explanation of the laws governing the multiverse, and the only viable candidate for a complete "theory of everything."

Time and ABC News have excerpts.

The physics of free kicks

Why are long free kicks suprisingly effective in soccer matches? Science explains!

For a well-struck soccer ball, the researchers estimate, one might expect a gentle arc followed by a sharp hook at about 50 meters -- in rough agreement with the distance of Roberto Carlos's free kick. In other words, if a soccer player has the strength to drive a ball halfway down the field with plenty of velocity and spin, he or she can expect to benefit from an unexpected curve late in the ball's trajectory.

But really, this is just an excuse to show you Roberto Carlos' amazing free kick against France in 1997:

Pure awesometown. But it might not be even be better than this one:

The speed of gravity

Newton said the speed of gravity is infinite but according to Einstein (and some nifty interstellar measurements), it most certainly is not.

But in general relativity, things are much more intricate, and incredibly interesting. First off, it isn't mass, per se, that causes gravity. Rather, all forms of energy (including mass) affect the curvature of space. So for the Sun and the Earth, the incredibly large mass of the Sun dominates the curvature of space, and the Earth travels in an orbit along that curved space.

If you simply took the Sun away, space would go back to being flat, but it wouldn't do so right away at every point. In fact, just like the surface of a pond when you drop something into it, it snaps back to being flat, and the disturbances send ripples outward!

Sun may affect radioactive decay rates

During a search for a radioactive isotope-based random number generator, researchers discovered that radioactive decay rates, previously thought to be constant, appear to be influenced by the activity of the Sun.

On Dec 13, 2006, the sun itself provided a crucial clue, when a solar flare sent a stream of particles and radiation toward Earth. Purdue nuclear engineer Jere Jenkins, while measuring the decay rate of manganese-54, a short-lived isotope used in medical diagnostics, noticed that the rate dropped slightly during the flare, a decrease that started about a day and a half before the flare.

If this apparent relationship between flares and decay rates proves true, it could lead to a method of predicting solar flares prior to their occurrence, which could help prevent damage to satellites and electric grids, as well as save the lives of astronauts in space.

The decay-rate aberrations that Jenkins noticed occurred during the middle of the night in Indiana -- meaning that something produced by the sun had traveled all the way through the Earth to reach Jenkins' detectors. What could the flare send forth that could have such an effect?

Jenkins and Fischbach guessed that the culprits in this bit of decay-rate mischief were probably solar neutrinos, the almost massless particles famous for flying at nearly the speed of light through the physical world -- humans, rocks, oceans or planets -- with virtually no interaction with anything.

Maybe the science part of 2012 wasn't so far-fetched after all. (No, not really.)

Slow motion lightning strike

A lightning strike recorded at 9000 frames per second.

The action across time scales displayed in this video is amazing. One strike hovers in the frame almost the entire time while other hundreds of other strikes flicker in and out in single frames.

Are you there God particle? It's me, Fermilab.

By further isolating where the Higgs boson isn't, scientists are finally closing in on the discovery of the so-called God particle...or proving that it doesn't exist at all.

Its mass -- in the units preferred by physicists -- is not in the range between 158 billion and 175 billion electron volts, according to a talk by Ben Kilminster of Fermilab at the International Conference on High Energy Physics in Paris.

Cancer-causing box springs?

Rates of breast cancer and melanoma in humans are on the rise and appear to favor the left side of the body. A suspected cause is that the box springs in our beds act as antennas to focus the EM radiation from FM radio and broadcast television directly into the left sides of our bodies. No, really:

Electromagnetic waves resonate on a half-wavelength antenna to create a standing wave with a peak at the middle of the antenna and a node at each end, just as when a string stretched between two points is plucked at the center. In the U.S. bed frames and box springs are made of metal, and the length of a bed is exactly half the wavelength of FM and TV transmissions that have been broadcasting since the late 1940s.

(thx, anna)

Update: So, you know when you run across something about some current scientific theory or hypothesis on a blog or in a magazine or newspaper or even in a scientific journal, there's a fair chance that whatever the article says is misleading, misstated, or even incorrect. That's just how it is and if you didn't know, now you do. Take this stuff with a grain of salt. It's why I use phrases like "suspected cause" instead of something like "box springs and FM radio proven to cause cancer".

I don't post things like this because I think they're right, I post them because I think they are interesting. The geometry of TV signals and box springs causing cancer on the left sides of people's bodies in Western countries...that's a clever bit of hypothesizing, right or wrong.

In this case, an organization I know nothing about (Vetenskap och Folkbildning from Sweden) says that Olle Johansson, one of the researchers who came up with the box spring hypothesis, is a quack. In fact, he was "Misleader of the year" in 2004. What does this mean in terms of his work on box springs and cancer? I have no idea. All I know is that on one side you've got Olle Johansson, Scientific American, and the peer-reviewed journal (Pathophysiology) in which Johansson's hypothesis was published. And on the other side, there's Vetenskap och Folkbildning, a number of commenters on the SciAm post, and a bunch of people in my inbox. Who's right? Who knows. It's a fine opportunity to remain skeptical. (thx, tom)

DNA and quantum entanglement

Does quantum entanglement hold DNA together? Some physicists say it's possible.

Rieper and co ask what happens to these oscillations, or phonons as physicists call them, when the base pairs are stacked in a double helix.

Phonons are quantum objects, meaning they can exist in a superposition of states and become entangled, just like other quantum objects.

To start with, Rieper and co imagine the helix without any effect from outside heat. "Clearly the chain of coupled harmonic oscillators is entangled at zero temperature," they say. They then go on to show that the entanglement can also exist at room temperature.

That's possible because phonons have a wavelength which is similar in size to a DNA helix and this allows standing waves to form, a phenomenon known as phonon trapping. When this happens, the phonons cannot easily escape. A similar kind of phonon trapping is known to cause problems in silicon structures of the same size.

Ancient Roman shipwreck aids in neutrino search

Lead ingots carried by a Roman ship sunk in 50 BC will be used to study the decay of neutrinos. Neutrino experiments are very delicate and need to be shielded from radioactive contamination, including possible contamination from the shielding itself.

This vast stretch of time means that the tiny amount of the radioactive isotope lead-210 originally present in the ingots, just as it exists in any normal lead object, has by now almost completely disappeared.

(via history blog)

Making a tiny star on Earth?

Not content with movie stars, California wants its own actual stellar object. The LIFE project at the NIF (National Ignition Facility) at the Lawrence Livermore National Laboratory aims to create a tiny star with intense laser power. How intense? The facility increases the power of the laser beam a quadrillion times before it reaches its target:

The National Ignition Facility, located at Lawrence Livermore National Laboratory, is the world's largest laser system... 192 huge laser beams in a massive building, all focused down at the last moment at a 2 millimeter ball containing frozen hydrogen gas. The goal is to achieve fusion... getting more energy out than was used to create it. It's never been done before under controlled conditions, just in nuclear weapons and in stars. We expect to do it within the next 2-3 years. The purpose is threefold: to create an almost limitless supply of safe, carbon-free, proliferation-free electricity; examine new regimes of astrophysics as well as basic science; and study the inner-workings of the U.S. stockpile of nuclear weapons to ensure they remain safe, secure and reliable without the need for underground testing.

Wow. The fusion will produce high-energy neutrons, which will bombard a material capable of converting their energy into heat, which in turn will make steam and eventually electricity. But it gets even better:

In addition, the LIFE engine design can be "charged" with fission fuel. The resulting fission reactions will produce additional energy that can be harvested for electricity production. Moreover, by using depleted uranium or spent nuclear fuel from existing nuclear power plants in the blanket, a LIFE engine will be capable of burning the by-products of the current nuclear fuel cycle. Because the fusion neutrons are produced independently of the fission process, the fission fuel could be used without reprocessing. In this way, LIFE may be able to consume nuclear waste as fuel, mitigate against further nuclear proliferation, and provide long-term sustainability of carbon-free energy. A LIFE engine, via pure fusion or through the combination of fusion and fission, will generate the steady heat required to drive turbines for generating from 1,000 to 2,500 MW of safe, environmentally attractive electric power 24 hours a day for decades.

Also, free unicorns for everyone!

Can the human eye see individual pixels on iPhone 4?

Phil Plait of Bad Astronomy takes on Steve Jobs' claim that iPhone 4's pixels are too small for the human eye to see individually. I have confidence in Plait's conclusions:

I know a thing or two about resolution as well, having spent a few years calibrating a camera on board Hubble.

He may as well have pulled Marshall McLuhan out from behind a movie poster.

The magic levitating top

When this magnetic top is set spinning over another magnet, it levitates. No superconduction necessary.

(via @ebertchicago)

How to build a time machine

According to Stephen Hawking, there are three good ways to do it.

If we want to travel into the future, we just need to go fast. Really fast. And I think the only way we're ever likely to do that is by going into space. The fastest manned vehicle in history was Apollo 10. It reached 25,000mph. But to travel in time we'll have to go more than 2,000 times faster. And to do that we'd need a much bigger ship, a truly enormous machine. The ship would have to be big enough to carry a huge amount of fuel, enough to accelerate it to nearly the speed of light. Getting to just beneath the cosmic speed limit would require six whole years at full power.

Negative Twenty Questions

Physicist John Wheeler devised a variant of the Twenty Questions game called Negative Twenty Questions in which, unbeknownst to the guesser, everyone privately picks their own object, resulting in a game where both the guesser and the object choosers are required to narrow their choice in object with each round.

When returning Joe (let's call him) asks the standard bigger-than-a-breadbox question, if the first person says no, then the other players, who may have selected objects that are bigger, now have to look around the room for something that fits the definition. And if "Is it Hollow?" is Joe's next question, then any of the players who chose new and unfortunately solid objects now have to search around for a new appropriate object. As Murch says, "a complex vortex of decision making is set up, a logical but unpredictable chain of ifs and thens." Yet somehow this steady improvisation finally leads -- though not always, there's the tension -- to a final answer everyone can agree with, despite the odds.

Wheeler thought the game resembled how quantum mechanics worked.

Would a lava lamp work on Jupiter?

In order to see if a lava lamp would still function on Jupiter, Neil Fraser built a large centrifuge to try it out. This is the best homemade centrifuge video you'll see today:

He used the accelerometer on an Android phone to measure the G force.

The centrifuge is a genuinely terrifying device. The lights dim when it is switched on. A strong wind is produced as the centrifuge induces a cyclone in the room. The smell of boiling insulation emanates from the overloaded 25 amp cables. If not perfectly adjusted and lubricated, it will shred the teeth off solid brass gears in under a second. Runs were conducted from the relative safety of the next room while peeking through a crack in the door.

Beams crossed at LHC

CERN finally spun up the Large Hadron Collider and smashed some protons together.

"If you want to discover new particles, you have to produce them; and these new particles are massive. To produce them, you need higher energies. For the first time [on Tuesday], we will be producing particles that have energy 3.5 times higher than the maximum energy achieved so far. [...] At the end of the 7 TeV (3.5 TeV per beam) experimental period, the LHC will be shut down for maintenance for up to a year. When it re-opens, it will attempt to create 14 TeV events.

A universe of information

Perhaps the framework of the Universe is information and that forces like gravity are emergent phenomena.

Verlinde suggested that gravity is merely a manifestation of entropy in the Universe. His idea is based on the second law of thermodynamics, that entropy always increases over time. It suggests that differences in entropy between parts of the Universe generates a force that redistributes matter in a way that maximises entropy. This is the force we call gravity.

I'm a sucker for would-be GUTs; this one seems especially interesting to consider.

Quantum mechanics just got REAL

The opening paragraph of the article says it all:

A team of scientists has succeeded in putting an object large enough to be visible to the naked eye into a mixed quantum state of moving and not moving.

Wait, what? Like, WHAT? Ok, let's start over:

Andrew Cleland at the University of California, Santa Barbara, and his team cooled a tiny metal paddle until it reached its quantum mechanical 'ground state' -- the lowest-energy state permitted by quantum mechanics. They then used the weird rules of quantum mechanics to simultaneously set the paddle moving while leaving it standing still.

The fuck? In my day, we were taught, with the help of non-graphing calculators and paper notebooks, that quantum mechanics was a lot of wand-wavey nonsense about wave/particle duality that you never had to worry about because it belonged to some magical tiny land that no one visits with their actual eyes. This...this is straight-up magic. [Cue Final Countdown]

The physics of free throw shooting

Attention @THE_REAL_SHAQ: it's all about parabolas and backspin.

Free-throw success is also improved by adding a little backspin, which pushes the ball downward if it hits the back of the rim. The North Carolina State engineers calculated the ideal rate of free-throw backspin at three cycles per second. That is, a shot that takes one second to reach the basket will make three full revolutions counterclockwise as seen from the stands on the player's right side.

(via mr)

4 trillion degrees Celsius

Using the Relativistic Heavy Ion Collider at the Brookhaven National Laboratory on Long Island, particle physicists have succeeded in creating quark-gluon plasma, the temperature of which is 4 trillion degrees Celsius (about 250,000 times hotter than the center of the Sun). The plasma is believed to be the state the universe was in a microsecond after its creation.

The departure from normal physics manifested itself in the apparent ability of the briefly freed quarks to tell right from left. That breaks one of the fundamental laws of nature, known as parity, which requires that the laws of physics remain unchanged if we view nature in a mirror.

This happened in bubbles smaller than the nucleus of an atom, which lasted only a billionth of a billionth of a billionth of a second. But in these bubbles were "hints of profound physics," in the words of Steven Vigdor, associate director for nuclear and particle physics at Brookhaven. Very similar symmetry-breaking bubbles, at an earlier period in the universe, are believed to have been responsible for breaking the balance between matter and its opposite antimatter and leaving the universe with a preponderance of matter.

Black hole simulation

Were you to be close to a black hole, this program shows you what you might observe.

The optical appearance of the stellar sky for an observer in the vicinity of a black hole is dominated by bending of light, frequency shift, and magnification caused by gravitational lensing and aberration. Due to the finite apperture of an observer's eye or a telescope, Fraunhofer diffraction has to be taken into account. Using todays high performance graphics hardware, we have developed a Qt application which enables the user to interactively explore the stellar sky in the vicinity of a Schwarzschild black hole. For that, we determine what an observer, who can either move quasistatically around the black hole or follow a timelike radial geodesic, would actually see.

For Linux and Windows only, although there are sample videos for non-downloaders or those on other machines.

Nature's quantum computers

One of the big bummers about quantum computing is the cold temperatures required (hundreds of degrees below zero). However, a number of researchers believe that certain algae and bacteria perform quantum calculations at room temperature.

The evidence comes from a study of how energy travels across the light-harvesting molecules involved in photosynthesis. The work has culminated this week in the extraordinary announcement that these molecules in a marine alga may exploit quantum processes at room temperature to transfer energy without loss. Physicists had previously ruled out quantum processes, arguing that they could not persist for long enough at such temperatures to achieve anything useful.

(via mr)

Einstein's 1905 chronology

In 1905, Einstein came up with the concept of special relativity, published his paper on the photoelectric effect, finished his doctoral dissertation, devised the E=mc^2 concept, published a paper on Brownian motion, was approved for his doctorate, and turned 26.

So......what have you guys been up to?

Life is but a holographic projection

An experiment to detect gravitational waves may indicate that our universe is a holographic projection.

If this doesn't blow your socks off, then Hogan, who has just been appointed director of Fermilab's Center for Particle Astrophysics, has an even bigger shock in store: "If the GEO600 result is what I suspect it is, then we are all living in a giant cosmic hologram." [...] Our everyday experience might itself be a holographic projection of physical processes that take place on a distant, 2D surface.

My socks have been blown so far off they are in a parallel universe. We might be living in the shadow of Flatland. Read the whole thing...it's noodle-bending throughout. Reminds me of the discovery of cosmic background radiation. (via aegirthor)

Richard Feynman explains magnets, sort of

I really can't do a good job, any job, of explaining magnetic force in terms of something else you're more familiar with, because I don't understand it in terms of anything else you're more familiar with.

This is why science is so maddening for some and so great for others.

The gravity of the solar system

Today on xkcd, an illustration showing the gravity wells of our solar system's planets and some of their moons.

Two of Mars' tiny moons barely have any gravity at all:

You could escape Deimos with a bike and a ramp. A thrown baseball could escape Phobos.

That's great, but you forgot Pluto!

The physics of space battles

The logistics of fighting wars in space is a little different than the movies have lead us to believe.

For the same reason that we have Space Shuttle launch delays, we'll be able to tell exactly what trajectories our enemies could take between planets: the launch window. At any given point in time, there are only so many routes from here to Mars that will leave our imperialist forces enough fuel and energy to put down the colonists' revolt.

What will the LHC find?

With regard to the Large Hadron Collider, the Higgs boson gets all the press but other potential discoveries could be more exciting and easier to detect.

However, if the theorists are right, before it ever finds the Higgs, the LHC will see the first outline of something far bigger: the grand, overarching theory known as supersymmetry. SUSY, as it is endearingly called, is a daring theory that doubles the number of particles needed to explain the world. And it could be just what particle physicists need to set them on the path to fresh enlightenment.

If you haven't been keeping up with particle physics for the past few years (as I haven't), this will bring you up to speed a bit.

Natural nuclear reactors

Several naturally occurring nuclear reactors have been discovered in Gabon, Africa. Groundwater flooding deposits of uranium ore made the reaction possible.

The natural nuclear reactor formed when a uranium-rich mineral deposit became inundated with groundwater that acted as a neutron moderator, and a nuclear chain reaction took place. The heat generated from the nuclear fission caused the groundwater to boil away, which slowed or stopped the reaction. After cooling of the mineral deposit, short-lived fission product poisons decayed, the water returned and the reaction started again. These fission reactions were sustained for hundreds of thousands of years, until a chain reaction could no longer be supported. Fission of uranium normally produces five known isotopes of the fission-product gas xenon; all five have been found trapped in the remnants of the natural reactor, in varying concentrations. The concentrations of xenon isotopes, found trapped in mineral formations 2 billion years later, make it possible to calculate the specific time intervals of reactor operation: approximately 2 hours and 30 minutes

Nice try Fermi, but Mother Nature got there first.

BTW, despite reading The Making of the Atomic Bomb (twice!), I can't recall hearing this pair of anecdotes before:

Due to a mistranslation, Soviet reports on Enrico Fermi claimed that his work was performed in a converted "pumpkin field" instead of a "squash court", squash being an offshoot of hard racquets.

When the first self-sustained nuclear chain reaction was achieved, a coded phone call was made by one of the physicists, Arthur Compton, to James Conant, chairman of the National Defense Research Committee. The conversation was in impromptu code:

Compton: The Italian navigator has landed in the New World.
Conant: How were the natives?
Compton: Very friendly.

Pumpkin field, tube alloy, the Italian navigator, the Manhattan Project...the building of the atomic bomb had no shortage of fanciful language.

Update: BLDGBLOG did a post on fossil reactors recently, which is probably where I got the link above in the first place.

Seven questions that keep physicists up at night

At a recent conference, a group of physicists talked about the biggest answered (and perhaps unanswerable) questions in physics. Three of the questions are:

What is everything made of?
Will string theory ever be proved correct?
How far can physics take us?

The Higgs boson and the Enchantment Under the Sea dance

Are the problems that have plagued the Large Hadron Collider and previous high-energy efforts (SSC, I'm looking at you here) a result of the Higgs boson travelling back from the future to meddle in its own discovery? A pair of scientists think it's a possibility.

"It must be our prediction that all Higgs producing machines shall have bad luck," Dr. Nielsen said in an e-mail message. In an unpublished essay, Dr. Nielson said of the theory, "Well, one could even almost say that we have a model for God." It is their guess, he went on, "that He rather hates Higgs particles, and attempts to avoid them."

This malign influence from the future, they argue, could explain why the United States Superconducting Supercollider, also designed to find the Higgs, was canceled in 1993 after billions of dollars had already been spent, an event so unlikely that Dr. Nielsen calls it an "anti-miracle."

That's heavy, Doc.

Update: Bread from the future halted operation of the LHC again.

Magnetricity

Not every magnetic substance has a north and a south pole...some are monopolar.

The work is the first to make use of the magnetic monopoles that exist in special crystals known as spin ice.

Spin ice! Also I guess they went with the awkward magnetricity name because electromagnetism was taken. (via mouser, who says "Suck it, Maxwell")

Hammer vs. feather on the Moon

Nothing like a little science on the Moon, I always say.

Astronaut David Scott in 1971, from the Apollo 15 Lunar Surface Journal. Scott was part of the Apollo 15 crew, and applied Galileo's findings about gravity and mass by testing a falcon feather and a hammer. The film, shown in countless high school physics classes, is the nerdy, oft-neglected cousin of Neil Armstrong's space paces.

Bananas and antibananas

This interview with physicist Murray Gell-Mann contains several great moments, but I particularly liked the answer he gave when asked about how great his colleagues were:

I don't put people on pedestals very much, especially not physicists. Feynman [who won a 1965 Nobel for his work in particle physics] was pretty good, although not as good as he thought he was. He was too self-absorbed and spent a huge amount of energy generating anecdotes about himself. Fermi [who developed the first nuclear reactor] was good, but again with limitations-every now and then he was wrong. I didn't know anybody without some limitations in my field of theoretical physics.

I read one such anecdote involving Gell-Mann in a book some years ago:

Richard Feynman, Gell-Mann's chief competitor for the title of the World's Smartest Man but a stranger to pretension, once encountered Gell-Mann in the hall outside their offices at Caltech and asked him where he had been on a recent trip; "Moon-TRAY-ALGH!" Gell-Mann responded in a French accent so thick that he sounded as if he were strangling. Feynman -- who, like Gell-Mann, was born in New York City -- had no idea what he was talking about. "Don't you think," he asked Gell-Mann, when at length he had ascertained that Gell-Mann was saying "Montreal," "that the purpose of language is communication?"

(via 3qd)

Long physics lectures can kill you!

The answer to this Fermi problem is a bit surprising.

Assuming you're not in a big lecture hall and the professor shuts the door at the start of class, how long does it take for you and your classmates to deplete the oxygen enough to feel it?

Here's a taste of the reasoning behind the answer:

So one person needs about 2lb of oxygen a day, or .9 kg. But how many liters is that? Oxygen has a molar mass of 16 grams, so oxygen gas, or O2, has a mass of 32 grams per mole. One mole of gas at standard pressure and temperature takes up 22.4 liters.

A commenter over on Fine Structure notes that CO2 is more of a problem than oxygen.

I don't know if they brought this up on physicsbuzz yet, but lack of oxygen isn't really uncomfortable (though it can kill you). Increase in CO2 is what triggers the apparent need to breath. I am pretty sure the minimum partial pressure of O2 is around 0.16 bar. Actually, that is the min recommended, I don't know if that is the pass-out limit.

Best correction ever?

On July 17, 1969, The New York Times issued a correction related to an editorial the paper published in 1920 that dismissed the idea of rocket travel in the vacuum of space. The editorial read, in part:

That Professor Goddard, with his 'chair' in Clark College and the countenancing of the Smithsonian Institution, does not know the relation of action to reaction, and of the need to have something better than a vacuum against which to react -- to say that would be absurd. Of course he only seems to lack the knowledge ladled out daily in high school.

The correction stated:

Further investigation and experimentation have confirmed the findings of Issac Newton in the 17th Century and it is now definitely established that a rocket can function in a vacuum as well as in an atmosphere. The Times regrets the error.

The Times regrets the error! Wish I'd written that next to a few muffed physics exam questions. Here's a pretty good explanation of why rockets work in vacuums. (via @davidfg)

Seven hours of Feynman lectures online

With a little help from Bill Gates (who secured the rights using personal funds), Microsoft is presenting a series of lectures on physics by Richard Feynman. The lectures, shown in seven hour-long segments, were recorded by the BBC at Cornell University in 1964. Lecture titles are as follows:

Law of Gravitation - An Example of Physical Law
The Relation of Mathematics and Physics
The Great Conservation Principles
Symmetry in Physical Law
The Distinction of Past and Future
Probability and Uncertainty - The Quantum Mechanical View of Nature
Seeking New Laws

(thx, dan)

Sixty Symbols videos

From the folks who brought you The Periodic Table of Videos, Sixty Symbols is a series of videos on the symbols used in physics and astronomy. (via snarkmarket)

Of two minds on the pitcher's mound

If I ever write a book, it might have something to do with the two minds that govern creative expertise: the instinctual unconscious mind (the realm of relaxed concentration) and the thinking mind (the realm of deliberate practice). The tension between these two minds is both the key to and fatal flaw of human creativity. From the world of sports¹, here's Rockies pitcher and college physics major Jeff Francis describing the interplay of the minds on the mound:

Even though I do understand the forces and everything, there's a separation when I'm pitching. If I throw a good pitch, I know what I did to do it, but there has to be a separation between knowing what I did and knowing why what I did helped the ball do what it did, if that makes any sense at all. If I thought about it on the mound, I'd be really mechanical and trying to be too perfect instead of doing what comes naturally.

But you don't need to be a physics major to wrestle with the consequences of the conflict between the two minds. After an injury and subsequent surgery, Francis' instinctual mind works to protect his body from further injury:

Francis repeatedly pulled the ball back in preparation to throw. But as he flashed his arm forward, his hand would, mind unaware, bring the ball back toward his ear rather than at full extension. It was his body essentially shortening the axis of his arm to decrease the force on his shoulder, protecting him from pain. And Francis could not stop it.

After his 10th pitch and first muffled groan of pain, he stopped.

"It's hurting you?" Murayama said.

"Yeah," Francis said.

"I can tell. You're getting out ahead of your arm. Slow down, stay back a little more."

"Does it look like I'm scared to throw a little?"

"Are you scared?"

"Not consciously."

To fully recover and regain his former effective pitching motion, Francis will utilize his thinking mind to retrain his unconscious mind through deliberate practice to ignore the injury potential. (thx, adriana)

[1] Most of the examples I've cited over the years deal with sports, mostly because professional athletes are among the most trained, scrutinized, studied, and optimized creative workers in the world. For a lot of other professions and endeavors, the data and scrutiny just isn't as evident. ↩

Feynman on trains

Richard Feynman explains how trains stay on their tracks.

Hint: it's not the flanges. (via jb)

More extrasolar planetary news

Oliver Morton fills us in on the current happenings in the search for planets outside of our solar system. A friend of his clued him in on a technique that could be used to not only discover planets but to determine if those planets show signs of supporting Earth-like life.

When they are passing in front of their stars, their atmospheres are backlit in a way that can make spectroscopic analysis of the different chemicals in their atmospheres comparatively easy: the wavelengths of light absorbed by the various chemicals will show up, in a tiny way, in the spectrum of the starlight. And this is what makes it possible to imagine looking at them for signs of life.

What scientists would look for are planets with unstable atmospheres, which James Lovelock said was an indication of life.

After the extragalactic planet post this morning, Sam Arbesman sent me a link to systemic, a blog dedicated to the search for extrasolar planets written by Greg Laughlin, one of the scientists involved in the effort. Here are two relevant posts. In Forward, Laughlin says we're very close to finding a nearby Earth-like planet:

Detailed Monte-Carlo simulations indicate that there's a 98% probability that TESS will locate a potentially habitable transiting terrestrial planet orbiting a red dwarf lying closer than 50 parsecs. When this planet is found, JWST (which will launch near the end of TESS's two year mission) can take its spectrum and obtain resolved measurements of molecular absorption in the atmosphere.

In Too cheap to meter, Laughlin presents a formula for the land value of such a discovery that depends on how far away the planet is, the age of the star it orbits, and the star's visual magnitude.

Applying the formula to an exact Earth-analog orbiting Alpha Cen B, the value is boosted to 6.4 billion dollars, which seems to be the right order of magnitude. And applying the formula to Earth (using the Sun's apparent visual magnitude) one arrives at a figure close to 5 quadrillion dollars, which is roughly the economic value of Earth (~100x the Earth's current yearly GDP)...

First extragalactic planet?

Scientists may have found the first planet located in another galaxy. The evidence is a little sparse but the search technique they're using is solid.

The idea is to use gravitational microlensing, in which a distant source star is briefly magnified by the gravity of an object passing in front of it. This technique has already found several planets in our galaxy, out to distances of thousands of light years. Extending the method from thousands to millions of light years won't be easy, says Philippe Jetzer of the University of Zurich in Switzerland, but it should be possible.

Really big particles

As the universe expanded, neutrinos formed in the Big Bang may have been stretched to billions of light years across.

Floating frogs (with video!)

If you've got a 16 tesla magnetic field, you can levitate a frog.

The levitation trick works because giant magnetic fields slightly distort the orbits of electrons in the frog's atoms. The resulting electric current generates a magnetic field in the opposite direction to that of the magnet. A field of 16 teslas created an attractive force strong enough to make the frog float until it made its escape.

Best part: it doesn't kill the frog. (via afrooz)

Update: Video of the levitating frog:

See also levitating strawberry, levitating grasshopper, and levitating water droplets. (thx, jesse)

Cold fusion?

Cold fusion is back in the news.

After two to three weeks, the team found a small number of "triple tracks" in the plastic -- three 8-micrometre-wide pits radiating from a point (see diagram, top right). The team says such a pattern occurs when a high-energy neutron strikes a carbon atom inside the plastic and shatters it into three charged alpha particles that rip through the plastic leaving tracks.

It'll be interesting to see if this can be replicated and the source of the neutrons verified.

The unobserved tree makes noise

Two independent groups of scientists have recently confirmed that the universe does exist when we are not observing it.

The reality in question -- admittedly rather a small part of the universe -- was the polarisation of pairs of photons, the particles of which light is made. The state of one of these photons was inextricably linked with that of the other through a process known as quantum entanglement. The polarised photons were able to take the place of the particle and the antiparticle in Dr Hardy's thought experiment because they obey the same quantum-mechanical rules. Dr Yokota (and also Drs Lundeen and Steinberg) managed to observe them without looking, as it were, by not gathering enough information from any one interaction to draw a conclusion, and then pooling these partial results so that the total became meaningful.

That's a relief, although the head of one of the group called their results "preposterous", so perhaps we're still not really here.

Garrett Lisi's Theory of Everything

You may remember reading the New Yorker article on Garrett Lisi, a surfer, physicist, and snowboarder who came out of nowhere in 2007 to present a plausible Theory of Everything, "a unifying idea that aims to incorporate all the universe's forces in a single mathematical framework". I do but I missed this visualization of Lisi's theory posted by New Scientist in late 2007. You may want to break out the bong for this one. (thx, matt)

Physics doesn't apply to much of the universe

In response to John Brockman's Edge Annual Question for 2009:

What will change everything? What game-changing scientific ideas and developments do you expect to live to see?

Stuart Kauffman says that we'll come to believe that much of the universe cannot be explained by or reduced to the fundamental laws of physics.

Let me point to the Adjacent Possible of the biosphere. Once there were lung fish, swim bladders were in the Adjacent Possible of the biosphere. Before there were multicelled organisms, the swim bladder was not in the Adjacent Possible of the biosphere. Something wonderful is happening right in front of us: When the swim bladder arose it was of selective advantage in its context. It changed what was Actual in the biosphere, which in turn created a new Adjacent Possible of the biosphere. The biosphere self consistently co-constructs itself into its every changing, unstatable Adjacent Possible.

If the becoming of the swim bladder is partially lawless, it certainly is not entailed by the fundamental laws of physics, so cannot be deduced from physics. Then its existence in the non-ergodic universe requires an explanation that cannot be had by that missing entailment. The universe is open.

(via david galbraith)

Video game physics

An examination of gravity in the Super Mario Bros series.

We determined that, generally speaking, the gravity in each Mario game, as game hardware has increased, is getting closer to the true value of gravity on earth of 9.8 m/s^2. However, gravity, even on the newest consoles, is still extreme.

In Super Mario 2, Mario experiences a g-force of 11 each time he falls from a ledge, a force that would cause mere humans to black out. In Madden 2006, the game's fastest cornerbacks can run the 40 in 2.6 seconds. (via waxy)

Five physics lessons for Obama

Five quick physics lessons for President-Elect Obama from the author of Physics for Future Presidents (@ Amazon). One of the lessons: nuclear power is the way to go.

It's true that after 300 years, nuclear waste is still about 100 times more radioactive than the original uranium that was removed from the earth. But even this isn't as scary as it sounds. If the waste is stored underground in such a way that there's only a 10 percent chance that 10 percent of it will leak -- which should be more than doable -- the risk will be no worse than if we had never mined the uranium in the first place.

Muller asserts that safe nuclear power is a solved technical problem and that the use of it is a political issue.

Useful black holes

A list of 15 uses of tiny black holes, including hazardous waste disposal, cheap transport, and hanging posters without tacks.

Big black holes

It looks like black holes can grow to be as massive as 50 billion suns. How massive is that? It's approximately 99 duodecillion kilograms....which is a 99 followed by 39 zeros. (Put another way, if you had 99 duodecillion dollars, you could buy as many PlayStation 3s as you wanted. Blows your mind, right?)

Faster-than-light communication

In a Swiss experiment, two entangled photons 18 km away from each other were able to communicate with each other almost instantaneously.

On the basis of their measurements, the team concluded that if the photons had communicated, they must have done so at least 100,000 times faster than the speed of light -- something nearly all physicists thought would be impossible. In other words, these photons cannot know about each other through any sort of normal exchange of information.

Update: Hrm, the link above scampered behind Nature's paywall. Here's a post on the Scientific American blog instead.

What will the LHC find?

A list of possible discoveries by the Large Hadron Collider and the probability of each discovery being made within the next five years.

The Higgs Boson: 95%. The Higgs is the only particle in the Standard Model of Particle Physics which hasn't yet been detected, so it's certainly a prime target for the LHC (if the Tevatron doesn't sneak in and find it first). And it's a boson, which improves CERN's chances. There is almost a guarantee that the Higgs exists, or at least some sort of Higgs-like particle that plays that role; there is an electroweak symmetry, and it is broken by something, and that something should be associated with particle-like excitations. But there's not really a guarantee that the LHC will find it. It should find it, at least in the simplest models; but the simplest models aren't always right. If the LHC doesn't find the Higgs in five years, it will place very strong constraints on model building, but I doubt that it will be too hard to come up with models that are still consistent.

The list also functions as a nice overview of what's happening at the edges of our physics understanding. (via 3qd)

Physical theories as women

If physical theories were women.

Quantum mechanics is the girl you meet at the poetry reading. Everyone thinks she's really interesting and people you don't know are obsessed about her. You go out. It turns out that she's pretty complicated and has some issues. Later, after you've broken up, you wonder if her aura of mystery is actually just confusion.

Would like to see the list for men as well. (via snarkmarket)

Famous physicists on money

Physicists of the 20th Century on Banknotes (5 MB PDF), including Marie & Pierre Curie on a short-lived 500 franc note, Niels Bohr on a Danish 500 kroner note, and Nikola Tesla on several notes from Yugoslavia and Serbia. The author of the article is Steve Feller, physics professor at Coe College and my college advisor. Feller has a keen interest in numismatics and recently published a book about the money used in WWII camps.

The death of gallium

Humans are consuming natural resources so quickly that we're running out of elements.

The element gallium is in very short supply and the world may well run out of it in just a few years. Indium is threatened too, says Armin Reller, a materials chemist at Germany's University of Augsburg. He estimates that our planet's stock of indium will last no more than another decade. All the hafnium will be gone by 2017 also, and another twenty years will see the extinction of zinc. Even copper is an endangered item, since worldwide demand for it is likely to exceed available supplies by the end of the present century.

Many of the elements listed above are used in the construction of computer equipment and flat-panel TVs.

Iconic Hubble photos

From Harvard Magazine, an appreciation of the work that the Hubble telescope has done since its 1990 launch into orbit.

The "Pillars of Creation" may be the most iconic Hubble photograph ever taken. "Located in the Eagle Nebula, the pillars are clouds of molecular hydrogen, light years in length, where new stars are being born," says Aguilar. "However, recent discoveries indicate these pillars were destroyed by a massive nearby super nova some 6,000 years ago. This is a ghost image of a past cosmic disaster that we won't see here on Earth for another thousand years or so-and a perfect example of the fact that everything we see in the universe is history."

Fractal universe

Is the universe fractal-like, even on large scales? A group of Italian and Russian scientists argue that it displays a fractal pattern on a scale of 100 million light years. Other scientists aren't so sure.

Many cosmologists find fault with their analysis, largely because a fractal matter distribution out to such huge scales undermines the standard model of cosmology. According to the accepted story of cosmic evolution, there simply hasn't been enough time since the big bang nearly 14 billion years ago for gravity to build up such large structures.

Pioneer anomaly update

Here's an update on the effort to solve the Pioneer anomaly, the unexplained deviation in motion of deep space probes from what Newton and Einstein's theories predict.

As it sped through space, a specialist in radio-wave physics named John Anderson at NASA's Jet Propulsion Laboratory noticed an odd thing. The spacecraft was drifting off course. The discrepancy was less than a few hundred-millionths of an inch per second for every second of spaceflight, accumulating year after year across billions of miles. Then Pioneer 11, an identical probe escaping the solar system in the opposite direction, also started to veer off course at the same rate.

Ordinarily, such small deviations might be overlooked, but not by Dr. Anderson. He monitored the trajectories six years before calling attention to the matter. "I'm a little like an accountant," Dr. Anderson said. "We have Newton's theory and Einstein's theory, and when you apply them to something like this -- and it doesn't add up -- it bothers me."

The researchers, using data recovered from recently discovered Pioneer records and funded by sources outside of NASA, have figured out part of the problem but the rest remains a mystery.

I missed this earlier this week: physicist

I missed this earlier this week: physicist John Wheeler has died at the age of 96. A snippet from the NY Times obituary:

At the same time, he returned to the questions that had animated Einstein and Bohr, about the nature of reality as revealed by the strange laws of quantum mechanics. The cornerstone of that revolution was the uncertainty principle, propounded by Werner Heisenberg in 1927, which seemed to put fundamental limits on what could be known about nature, declaring, for example, that it was impossible, even in theory, to know both the velocity and the position of a subatomic particle. Knowing one destroyed the ability to measure the other. As a result, until observed, subatomic particles and events existed in a sort of cloud of possibility that Dr. Wheeler sometimes referred to as "a smoky dragon."

This kind of thinking frustrated Einstein, who once asked Dr. Wheeler if the Moon was still there when nobody looked at it.

Wheeler recognized that physics is about ideas and the language used to express those ideas, not just mathematics and experimentation. He coined and popularized several phrases during his long career, including black hole, wormhole, and quantum foam.

Helicopter on a turntable

The airplane on a conveyor belt question was just recently settled and we're confronted with a related question: will a helicopter on a turntable take off? The image is short on details and likely a joke, but let's assume that the turntable will match the speed of the helicopter's rotor (and further that the rotor's speed is measured relative to the helicopter and the turntable's speed is relative to the ground, otherwise it doesn't make much sense). Will the helicopter take off? Does it matter which way the turntable is spinning relative to the rotor? (thx, daniel)

I did embarrassingly bad on this Elements

I did embarrassingly bad on this Elements of the Periodic Table quiz. I blanked after naming 17 elements in 2 minutes. Oh, and xylophone is not an element! My physics degree should be retroactively unawarded. (via mouser)

Solar furnaces

A solar furnace is a structure used to harness the rays of the sun in order to produce high temperatures. This is achieved by using a curved mirror (or an array of mirrors) acting as a parabolic reflector to concentrate light (Insolation) on to a focal point. The temperature at the focal point may reach up to 3,000 degrees Celsius, and this heat can be used to generate electricity, melt steel or make hydrogen fuel.

Whoa! Here's a great photo of a solar furnace in Uzbekistan and an even better photo of said furnace melting aluminum (close-up).

If you've got an old TV, you can use the Fresnel lens to make a solar furnace of your own. Caveats apply:

DANGER! This device is extremely dangerous. It should not be constructed or operated by anyone who does not observe proper safety precautions. It will instantly destroy flesh. It will melt metals, ceramics, and most any other material. Always wear welding goggles when operating this device! DO NOT leave this device unattended.

This DIY solar furnace is capable of melting brick (!!) and will "boil" a quarter in ~25 seconds.

Solar furnaces and the like have been around for centuries. In the 3rd century BC, Archimedes allegedly used a mirror to burn up the entire Roman fleet during the seige of Syracuse:

When Marcellus withdrew them [his ships] a bow-shot, the old man [Archimedes] constructed a kind of hexagonal mirror, and at an interval proportionate to the size of the mirror he set similar small mirrors with four edges, moved by links and by a form of hinge, and made it the centre of the sun's beams--its noon-tide beam, whether in summer or in mid-winter. Afterwards, when the beams were reflected in the mirror, a fearful kindling of fire was raised in the ships, and at the distance of a bow-shot he turned them into ashes. In this way did the old man prevail over Marcellus with his weapons.

This assertion was tested at MIT and on Mythbusters with mixed results. (via delicious ghost)

NY Times columnist and economist Paul Krugman

NY Times columnist and economist Paul Krugman wrote a paper when he was an assistant professor in 1978 called The Theory of Interstellar Trade. Here's the abstract:

This paper extends interplanetary trade theory to an interstellar setting. It is chiefly concerned with the following question: how should interest charges on goods in transit be computed when the goods travel at close to the speed of light? This is a problem because the time taken in transit will appear less to an observer travelling with the good than to a stationary observer. A solution is derived from economic theory, and two useless but true theorems are proved.

Why does the woman depicted in the

Why does the woman depicted in the Mona Lisa appear to be both smiling and not smiling at the same time? The smile part of the Mona Lisa's face was painted by Leonardo in low spatial frequencies. This means that when you look right at her mouth, there's no smile. But if you look at her eyes or elsewhere in the portrait, your peripheral vision picks up the smile. (via collision detection)

A series of four lectures on physics,

A series of four lectures on physics, specifically quantum electrodynamics, by Richard Feynman. Only Part 1 is available on Google Video and the rest are in streaming Real format (blech)...hopefully they too will make their way onto Google Video.

Update: Another lecture by Feynman, this one about Elementary Particles and the Laws of Physics.

Update: I got an email from the nice folks at Vega Science Trust asking me to change the wording of this entry with regard to encouraging people to put these copyrighted videos up on Google Video. Fair enough...what I really meant by that is I wish the videos were presented in a more useable manner than RealVideo format. If there's one thing that YouTube has shown us more than anything, it's that people find watching video in embedded Flash players really convenient.

Mythbusters, airplane on a conveyor belt

Starting in about 40 minutes, I'll be liveblogging the Mythbusters episode where they take on the infamous airplane on a conveyor belt problem. Updates will be reverse chronological (newest at the top) so don't scroll down if you're DVRing the episode for later viewing or otherwise don't want anything spoiled.

Fair warning? Ok here we go.

10:32p I've turned comments on. Why not!!

10:04p
The plane took off so easily. The laws of physics are proven correct once again. But I'm not sure this is going to settle anything. I'm getting email as we speak that the test was unfair. Plane was too light. Tarp was pulled too slowly. Etc. But the thing is, it doesn't matter how large the plane is...given enough runway and a strong enough conveyor belt, it will still take off. Ditto for the speed of the treadmill...it doesn't matter how fast the treadmill is moving. It could be going 300 mph in the opposite direction and as long as the bearings in the plane's wheels don't melt, it's gonna take off. (For an explanation, try this one by my friend Mouser, who has a MIT Ph.D in Physics Sc.D. in Nuclear Science and Engineering.)

9:58p

Update: Due to popular demand, the above graphic is available on a t-shirt at CafePress. Prices start at $18 and they're available in men's and women's sizes.

9:58p
Heeeeeeeere we go.

9:56p
The pilot flying the ultralight is predicting that he won't be able to take off.

9:55p
Orville Wright died 60 years ago today.

9:50p
Cockroach mini-myth: cockroaches would survive a nuclear blast longer than humans but there were other kinds of bugs that fared better. Another commercial.

9:47p
Back to the shaving cream in the car prank. Now they're going to use A-B foam...they're trying to fill all the space in the car and perhaps explode it. Totally worked.

9:44p
Expedia commercial. Nice synergistic placement. Good work, Discovery Channel's ad sales team.

9:43p
Ok, to do the large-scale plane test, they're using a 2000 foot tarp and a 400 pound ultralight. Tarp is pulled in one direction and the plane tries to take off in the other direction. The wind is picking up and blowing the tarp runway all over the place. They're also having problems with punching holes in the tarp. They're going to try again after we hear some more about radioactive cockroaches. Aaaand, another commercial.

9:36p
Second mini-myth: if you freeze a can of shaving cream, cut it open, and then put the foam in a car, it will heat and expand to fill the car. One can did almost nothing. 50 cans didn't do too much either.

9:32p
Off to commercial again. Macbook Air ad. I don't understand all the whining about how expensive and underpowered it is. You can't get by with an 80 GB hard drive? Come on.

9:30p
Now a bit of explanation from the boys. (Things are moving faster now, which is welcome.) The thrust from the airplane acts upon the air so it doesn't matter too much what the runway is doing to the plane's wheels. And then back to the roach thing. They irradiated them (and some other bugs) and most of the roaches died. Still pending...

9:25p
Ok, they're dragging paper behind a Segway and trying to take off with the model airplane in the opposite direction. IT JUST TOOK OFF.

9:19p
Back to the roach thing. More recapping and a little bit more setup. I don't see how people can watch this show...it's sooooo slooooow. And now another commercial break. Hello picture-in-picture.

9:18p
As expected, the model airplane "flew" off the end of the exercise treadmill. It didn't have enough room to take off, but if it stayed straight, it probably would have.

9:14p
First recap...they took a solid minute to explain what they've already done. Ugh.

9:13p
Going into the first commercial, we've caught a glimpse of how they're going to test the main myth. They're going to drag a huge plastic sheet long the ground and have the plane sit on the plastic and being going the other way attempting to take off. A reasonable substitute for the treadmill.

9:08p
They're starting off small with a model airplane on an exercise treadmill. They're showing the two hosts learning how to fly the tiny airplane. One of them is riding around on a Segway. Oh, and they're also doing two other mini-myths during the episode. They just switched gears to the first mini-myth: can a cockroach survive a nuclear blast?

9:04p
And we're off. They're calling it "the moment we've all been waiting for". My guess: the plane will take off.

8:58p
I've only watched one other episode of Mythbusters before today. I found the show to be a little slow and very repetitive; 8 minutes of material stretched into 45 minutes of show. Unfortunately, this practice seems to be common among science programs on television.

8:40p
Watching Family Guy as a warmup. The one with the nudist family. Good stuff.

8:22p
Preemptive answer for the inevitable "Do you realize how boring/stupid/goofy it is to liveblog this?" Most definitely.

For real this time: Mythbusters will air

For real this time: Mythbusters will air their challenge of the airplane on a conveyor belt puzzle this Wednesday at 9pm ET. (thx, darin)

Absolute Zero looks like an interesting show

Absolute Zero looks like an interesting show on cold temperatures, airing on PBS in mid-January. For the Long Zoom fans out there, don't miss the Sense of Scale widget.

The closure, it draws near. Remember the

The closure, it draws near. Remember the epic thread about the plane and the conveyor belt from last year...the one that pitted pilot against physicist against random internet commenter? In an upcoming episode of Mythbusters, they're going to air the results of a test they conducted with an ultralight and a quarter-mile-long conveyor belt:

If a plane is traveling at takeoff speed on a conveyor belt, and that conveyor belt is matching the speed in reverse, can the plane take off? "We put the plane on a quarter-mile conveyor belt and tested it out," says Savage about the experiment using a pilot and his Ultralight plane. "I won't tell you what the outcome was, but the pilot and his entire flight club got it wrong."

Awesome. If the laws of physics hold, that plane should take off. (thx, matt)

Scott Aaronson, Ph.D: Australian actresses are

Scott Aaronson, Ph.D: Australian actresses are plagiarizing my quantum mechanics lecture to sell printers. Here's a video of the printer commercial and the lecture notes from which the dialogue is taken.

Question of the day:

Question of the day:

You are shrunk to the height of a nickel and your mass is proportionally reduced so as to maintain your original density. You are then thrown into an empty glass blender. The blades will start moving in 60 seconds. What do you do?

The obvious answer is "die", but I don't think that's they're after here. I have an idea...but what say you?

Why does your shower curtain do that

Why does your shower curtain do that thing where it blows into you while you're showering? David Schmidt did some fluid-flow modeling and found that the spray creates a vortex (basically a low pressure region) which sucks the curtain in. (via cyn-c)

Is the search for aliens such a

Is the search for aliens such a good idea? If/when we find evidence of extraterrestrial intelligent life, will they welcome us as neighbors, treat us as vermin in their universe or something inbetween? "Jared Diamond, professor of evolutionary biology and Pulitzer Prize winner, says: 'Those astronomers now preparing again to beam radio signals out to hoped-for extraterrestrials are naive, even dangerous.'"

An illustration of how insanely effective water

An illustration of how insanely effective water is at absorbing heat: you can hold a water balloon over a candle without popping it. The rest of Robert Krampf's videos are worth a look as well.

Temporal anomalies in time travel movies, an

Temporal anomalies in time travel movies, an investigation of how time travel is represented in movies like Donnie Darko, 12 Monkeys, and Back to the Future. (via joshua)

Are there many small galaxies, like the

Are there many small galaxies, like the one just discovered just outside our own, orbiting the larger visible galaxies?

Embiggen, a perfectly cromulent word

Embiggen, the fauxcabulary word created for an episode of The Simpsons, has found its way into string theory. Here's the usage from a recently published paper on Gauge/gravity duality and meta-stable dynamical supersymmetry breaking:

Here's the original quote from The Simpsons episode, Lisa the Iconoclast:

A noble spirit embiggens the smallest man.

The uses are probably not related, but you never know.

The scale of the IceCube neutrino detector

The scale of the IceCube neutrino detector is amazing...a cubic kilometer telescope 1.5 miles deep into the ice caps of Antarctica. (via pruned, which has more thoughts on the architecture of particle physics)

Three trillion years from now, the universe

Three trillion years from now, the universe will be observably static, the Milky Way alone, and scientists of the day likely won't be able to "infer that the beginning involved a Big Bang".

How to survive a black hole. If

How to survive a black hole. If you're in a rocket ship about to fall into a black hole, you might live a bit longer if you turn on your engines. "But in general a person falling past the horizon won't have zero velocity to begin with. Then the situation is different -- in fact it's worse. So firing the rocket for a short time can push the astronaut back on to the best-case scenario: the trajectory followed by free fall from rest."

A pair of articles on the Large

A pair of articles on the Large Hadron Collider at CERN: A Giant Takes On Physics' Biggest Questions and Crash Course. The LHC will hopefully provide the 1.21 gigawatts 7 trillion electron volts needed to uncover the Higgs boson, aka, The God Particle. "What we want is to reduce the world to objects that have no structure, that are points, that are as simple as we can imagine. And then build it up from there again."

A recently discovered star appears to be 13.2

A recently discovered star appears to be 13.2 billion years old, just 500 million years younger than the Big Bang.

While working on a particle accelerator, Anatoli

While working on a particle accelerator, Anatoli Bugorski accidentally put his head into the proton stream. "The left half of Bugorski's face swelled up beyond recognition, and over the next several days started peeling off, showing the path that the proton beam (moving near the speed of light) had burned through parts of his face, his bone, and the brain tissue underneath." Some photos here. (via cyn-c)

Regarding the hypermiling business from last week,

Regarding the hypermiling business from last week, a question on Ask MetaFilter: Does a truck work extra to pull a drafting car?

A man outfitted his family minivan with

A man outfitted his family minivan with high-precision cesium clocks to demonstrate to his kids that they gained 22 nanoseconds of vacation time on their mountain camping trip than they would have at a lower altitude.

Remembering a physics conference that took place

Remembering a physics conference that took place in NYC 20 years ago about high-temperature superconductors. One session, the "Woodstock of Physics", lasted until 3:15 in the morning; "it was like the Texas chili cook-off or the Iowa State Fair apple pie bake-off." The conference was such a big deal at the time that physicists with conference badges were immediately ushered into a nightclub in Chelsea for free by the bouncers.

Regarding Susan Orlean's piece on Robert Lang

Regarding Susan Orlean's piece on Robert Lang and origami from a couple of weeks ago, the New Yorker has posted a 5-minute audio slideshow of Orlean talking about the piece.

Contributions of 20th Century Women to Physics.

Contributions of 20th Century Women to Physics.

New Scientist recently compiled a list of

New Scientist recently compiled a list of strange substances (with accompanying video): ferrofluids, non-Newtonian liquids, superfluids, and materials that get thicker when stretched. (via bb)

Does free will exist? "The conscious brain

Does free will exist? "The conscious brain was only playing catch-up to what the unconscious brain was already doing. The decision to act was an illusion, the monkey making up a story about what the tiger had already done."

"The Mpemba effect is the observation that,

"The Mpemba effect is the observation that, in some specific circumstances, hotter water freezes faster than colder water." I remember hearing about this on an old episode of Newton's Apple, but I think they never really got to the bottom of it on that show, which was highly disappointing to me at the time.

David Pogue and Boing Boing have been

David Pogue and Boing Boing have been ensnared by the airplane-on-a-treadmill problem we debated here last February. The airplane still takes off. :)

Physicists at the University of Washington are

Physicists at the University of Washington are hoping to use entangled photons to send information back in time. "Here's where it gets weird."

Man tries to jump the mile-wide St.

Man tries to jump the mile-wide St. Lawrence River in a rocket-powered Lincoln Continental. I don't want to spoil the result for you, but the concepts of gravity, force, and aerodynamics are fairly well established and understood, so why did anyone involved ever think that this jump was even close to possible?

Stephen Hawking is making an Imax 3D

Stephen Hawking is making an Imax 3D film about "cosmology and the meaning of existence". The film "will be like Groundhog Day meets Star Trek".

Jim Holt reports on a pair of

Jim Holt reports on a pair of books that argue that string theory is hurting theoretical physics. The article contains a good overview of the history and current status of the theory. For those looking to discover which book is better, Holt recommends Smolin's The Trouble with Physics.

Nobel Prize winning physicist Gerard 't Hooft

Nobel Prize winning physicist Gerard 't Hooft on how to become a good theoretical physicist. He lists the subjects you need to learn (from languages to quantum field theory) and resources (both online and off) for learning them. A note on the 't in his name.

Satellites measuring the earth's gravity from orbit

Satellites measuring the earth's gravity from orbit detected a change in gravity from the massive earthquake that caused the tsunami in the Indian Ocean. "The gravity at the earth's surface decreased by as much as about 0.0000015 percent, meaning that a 150-pound person would experience a weight loss of about one-25,000th of an ounce."

This image of the participants of a 1927

This image of the participants of a 1927 conference on quantum mechanics sets the record for the most brainpower in one photograph. Schrodinger, Pauli, Heisenberg, Dirac, Compton, Bohr, Einstein, Planck, Curie, de Broglie, and Lorenz, all in one place.

Update: A Great Day in Harlem depicts several of the world's top jazz musicians. More here. (thx, jim & greg)

On the heels of two books critical

On the heels of two books critical of string theory, a look at the string theory backlash.

Interesting tour/visualization imagining 10 dimensions. (thx, james)

Interesting tour/visualization imagining 10 dimensions. (thx, james)

Physicist Lawrence Krauss sums up his thoughts

Physicist Lawrence Krauss sums up his thoughts from a small conference he organized on the topic of gravity. "There appears to be energy of empty space that isn't zero! This flies in the face of all conventional wisdom in theoretical particle physics. It is the most profound shift in thinking, perhaps the most profound puzzle, in the latter half of the 20th century."

Vincent van Gogh painted turbulence quite accurately.

Vincent van Gogh painted turbulence quite accurately. Mexican scientists "have found that the Dutch artist's works have a pattern of light and dark that closely follows the deep mathematical structure of turbulent flow".

Spielberg's new film...a wormhole movie based

Spielberg's new film...a wormhole movie based on the work of Kip Thorne?

Stephen Hawking and Thomas Hertog are publishing

Stephen Hawking and Thomas Hertog are publishing a paper that argues that the universe "began in just about every way imaginable" simultaneously and then most of the possibilites withered away with the rest blending together to make the current universe.

Italian scientists have created glass made out

Italian scientists have created glass made out of carbon dioxide. At high pressure, instead of forming a crystal (dry ice), the CO₂ forms a clear, hard, vitreous material. More info. (Little known fact: I did research on glass in college, rubidium and cesium borosilicates mostly. Here's a few citations on Google Scholar.)

Bill and Ted's Excellent Adventure

I know I'm going to get mail about my five-star rating for this movie, but it cannot be helped. One summer when I was a kid, a friend and I watched Bill and Ted's Excellent Adventure -- no joke -- every single day for a span of 2 months. I still know every line by heart, the timing, inflection, everything. If there were a Broadway production of this movie, I could slide effortlessly into the role of either Bill S. Preston, Esq. or Ted Theodore Logan, no rehearsal needed.

In my high school physics class my senior year, we had to do a report on something we hadn't learned about in class -- which, I discovered when I got to college, was a lot -- and I did mine on time travel. I went to our small school library and read articles in Discover and Scientific American magazines about Stephen Hawking, Kip Thorne, quantum mechanics, causality, and wormholes. To illustrate the bit about wormholes, I brought in my well-worn VHS tape of Bill and Ted's (a dub of a long-ago video rental) and showed a short clip of the phone booth travelling through space and time via wormhole. I got a B+ on my presentation. The teacher told me it was excellent but marked me down because it was "over the heads" of everyone in the class...which I thought was completely unfair. How on earth is Bill and Ted's Excellent Adventure over anyone's head?

Get yer Richard Feynman on at Google

Get yer Richard Feynman on at Google Video, particularly this 50-minute video of The Pleasure of Finding Things Out. A bit more Feynman at YouTube.

This is the most wonderfully nerdy thing

This is the most wonderfully nerdy thing I've ever read about politics and blogging. "So in fact, Reynolds has managed to fit five units of wrongness into only four declarative statements! This is the hackular equivalent of crossing the Chandrasekhar Limit, at which point your blog cannot help but collapse in on itself." (via cyn-c)

Maybe the universe is a trillion years

Maybe the universe is a trillion years old and has experienced several big bangs and big collapses over the years. "People have inferred that time began then, but there really wasn't any reason for that inference. What we are proposing is very radical. It's saying there was time before the big bang."

Science blog Cocktail Party Physics has a

Science blog Cocktail Party Physics has a list of "physics cocktails" in the sidebar (scroll down a bit). The Black Hole is "so called because after one of these, you have already passed the event horizon of inebriation." Boy, am I a huge sucker for physics puns.

A moving mass has been shown to

A moving mass has been shown to generate a gravitomagnetic field (just like a moving electrical charge creates a magnetic field) and "the measured field is a surprising one hundred million trillion times larger than Einstein's General Relativity predicts". (via rw)

An Antarctic project has detected the first

An Antarctic project has detected the first neutrinos observed outside of a laboratory setting.

Still with the planes and conveyor belts

Now that I've closed the comments on the question of the airplane and the conveyor belt, I'm still getting emails calling me an idiot for thinking that the plane will take off. Having believed that after first hearing the question and formulating several reasons reinforcing my belief, I can sympathize with that POV, but that doesn't change the fact that I was initially wrong and that if you believe the plane won't take off, you're wrong too[1].

The only thing is, I'm not sure how to prove it to you if you don't understand the problem and the physics involved. I guess I could urge you to read the question and answer again carefully. I could tell you that not only does the conveyor belt not keep the plane stationary with respect to the ground but it *can't* keep that plane stationary with respect to the ground[2] and once you know that, of course it'll take off. My pal Mouser has a Ph.d in Physics from MIT and he says the plane will take off:

The airplane would take off normally, with the wheels spinning twice as fast as normal and a *slight* reduction in acceleration due to added friction.

Is that enough to convince you?

[1] This situation reminds me of Richard Dawkins' and Jerry Coyne's assertion that "one side can be wrong".

[2] The motion of the conveyor belt does nothing[3] to affect the movement of the plane when the plane is in motion...it doesn't matter if it's moving forward, backward, at 2 MPH, or at 400 MPH. If the plane were on castors that could spin freely from side to side as well as front to back, that treadmill could be spinning 100 MPH to the left and the plane would take off.

[3] Well, almost nothing. The friction of the turning wheels will slow things down a bit, but not enough to not make the plane take off. After all, the main function of the wheels of a plane is to provide a near-frictionless interface with the ground (or whatever the plane happens to be taking off from).

Robert Birnbaum interviews physicist Lisa Randall about

Robert Birnbaum interviews physicist Lisa Randall about string theory and science popularizers.

How do you find extra-solar planets? "I

How do you find extra-solar planets? "I think the techniques employed by planet-hunters are pretty cool so the following is a brief primer on how the techniques work and the pros and cons of each."

The case of the plane and conveyor belt

This question posed to Cecil at The Straight Dope has occupied most of my day today:

Here's the original problem essentially as it was posed to us: "A plane is standing on a runway that can move (some sort of band conveyer). The plane moves in one direction, while the conveyer moves in the opposite direction. This conveyer has a control system that tracks the plane speed and tunes the speed of the conveyer to be exactly the same (but in the opposite direction). Can the plane take off?"

I'll give you a few moments to think about that before discussing the answer...

...

...

...

Cecil says that the obvious answer -- that the plane does not take off because it remains stationary relative to the ground and the air -- is wrong. The plane, he says, can take off:

But of course cars and planes don't work the same way. A car's wheels are its means of propulsion--they push the road backwards (relatively speaking), and the car moves forward. In contrast, a plane's wheels aren't motorized; their purpose is to reduce friction during takeoff (and add it, by braking, when landing). What gets a plane moving are its propellers or jet turbines, which shove the air backward and thereby impel the plane forward. What the wheels, conveyor belt, etc, are up to is largely irrelevant. Let me repeat: Once the pilot fires up the engines, the plane moves forward at pretty much the usual speed relative to the ground--and more importantly the air--regardless of how fast the conveyor belt is moving backward. This generates lift on the wings, and the plane takes off. All the conveyor belt does is, as you correctly conclude, make the plane's wheels spin madly.

After reading the question this morning and discussing it with Meg for, oh, about 3 hours on and off, I was convinced that Cecil was wrong. There's no way that plane could take off. The conveyor belt keeps pace with the speed of the plane, which means the plane remains stationary from the POV of an observer on the ground, and therefore cannot lift off.

Then I read Cecil's answer again this evening and I've changed my mind; I'm fairly certain he's right. For a sufficiently long conveyor belt, that plane is taking off. It doesn't matter what the conveyor belt is doing because the airplane's energy is acting on the air, not the belt. I had better luck simplifying the problem like so: imagine instead of a plane, you've got a rocket with wheels sitting on that belt. When that rocket fires, it's eventually going to rocket off the end of that belt...which means that it doesn't remain stationary to the ground and if it had wings, it would fly.

What do you think? Can that plane take off?

See also Feynman's submerged sprinkler problem (answer) and an old argument of Newton and Huygens: can you swim faster through water or syrup?

Update: Well, that got out of control in a hurry...almost 300 comments in about 16 hours. I had to delete a bunch of trolling comments and it's not productive to keep going, so I closed it. Thanks for the, er, discussion and remember, the plane takes off. :)

Free 1200-page physics textbook, available online or

Free 1200-page physics textbook, available online or for download. I have no idea if it's any good or not. Is anyone using this in their high school or college classroom?

Lisa Randall and Raman Sundrum have proposed

Lisa Randall and Raman Sundrum have proposed some ideas about gravity, extra dimensionality, and string theory that may be testable when the Large Hadron Collider goes online at CERN in 2007.

Ever seen a crab get sucked into

Ever seen a crab get sucked into a pipe through a 3mm-wide slit? This is your chance.

Jim Holt asks Freeman Dyson, Lawrence Krauss,

Jim Holt asks Freeman Dyson, Lawrence Krauss, Ed Witten and other in trying to figure out how the universe will end. Further reading: Time Without End by Freeman Dyson, Frank Tipler's Omega Point theory, and The Physics of Extra-Terrestrial Civilizations by Michio Kaku.

A relativistic examination of gravity in the

A relativistic examination of gravity in the galaxy may indicate that the invention of dark matter may not be necessary to solve the not-enough-matter problem. "The motions of stars in galaxies is realized in general relativity's equations without the need to invoke massive halos of exotic 'dark matter' that nobody can explain by current physics."

Update: mjt has doubts about the paper referenced here and notes that there's other evidence for dark matter that is not questioned by the above study.

Scientists want to build an array of

Scientists want to build an array of submillimeter telescopes across the whole earth to peer "inside" the massive black hole at the center of the galaxy.

Update: Many people wrote in to correct me in saying that "submillimeter" referred to the size of the telescopes...it of course referred to the EM wavelength. Me brain not working right.

Brian Greene on Einstein's most famous equation,

Brian Greene on Einstein's most famous equation, E =mc^2. When he finally gets around to it in the middle of the article, Greene's got a pretty good layman's explanation of what the formula actually means.

Freeman Dyson on his friend and colleague

Freeman Dyson on his friend and colleague Richard Feynman for The New York Review of Books.

A rare interview with Stephen Hawking about

A rare interview with Stephen Hawking about his remix of A Brief History of Time. The interview's a bit weird...the interviewer doesn't seem to know a whole lot about science.

A couple of guys calculated the average

A couple of guys calculated the average color of the universe to be turquiose. Then it turned out they had made an error and the actual color of the universe is beige.

Odd story of one astronomer possibly "stealing"

Odd story of one astronomer possibly "stealing" another astronomer's discovery of a large trans-Neptunian object. The original discoverer alleges that the usurper looked at a couple of Web sites that detailed the discovery and where the discover's telescopes were pointed...the astronomy equivalent of stealing signs.

A sequel to Stephen Hawking's A Brief

A sequel to Stephen Hawking's A Brief History of Time: A Briefer History of Time. "More Accessible. More Concise."

The existence and behavior of dark matter

The existence and behavior of dark matter is puzzling indeed, but some UK astrophysicists speculate that adding three more spacial dimensions to the universe explains the gravitational behavior of dark matter. If they exist, these extra dimensions would be about a nanometer across. A baby step toward string theory?

Physicist Stephen Hawking has been reduced to

Physicist Stephen Hawking has been reduced to blinking to control his helper computer.

Adriana: "I thought you might be interested in a post I wrote a while back about a former editor of Elle who communicated for the last year of his life via blinks".

PBS has put up a companion web

PBS has put up a companion web site to the Nova program on Einstein airing in October. Features include audio clips of several physicists describing e=mc^2 to non-physicists.

When bent, why does dry spaghetti break

When bent, why does dry spaghetti break into three or more pieces instead of two? This was one of the simple problems Richard Feynman amused himself with but never solved. Someone's come up with the answer: when the first breakage occurs, it causes a local increase in the curvature of the two pieces, resulting in more breakage. (thx dj)

Modelling nuclear decay in atoms may tell

Modelling nuclear decay in atoms may tell us something about dating and relationships. One of the findings: people who date often are beneficial to the dating ecosystem "because they break up weak couples, forcing their victims to find better relationships".

Advice from Dr. Michio Kaku on formulating

Advice from Dr. Michio Kaku on formulating a proposal for the Unified Field Theory. I can just imagine all the crackpot theories that prompted this list.

Los Alamos From Below: Reminiscences 1943-1945, by Richard Feynman

Los Alamos From Below: Reminiscences 1943-1945, by Richard Feynman. Today marks the 60th anniversary of the first atomic bomb test which bomb Feynman helped build.

In celebration of its 125th anniversary, Science

In celebration of its 125th anniversary, Science magazine has a list of the 125 biggest questions facing science over the next 25 years. "How did cooperative behavior evolve?"; "Do deeper principles underlie quantum uncertainty and nonlocality?"; "What is the universe made of?"

It's not every day that a new

It's not every day that a new form of matter is created. Physicists at MIT have created something called a superfluid, "a gas of atoms that shows high-temperature superfluidity".

Researching quantum honeybees

Researching quantum honeybees. Can bees detect quantum fields and use them to find food?

"There is no physics theory that explains

"There is no physics theory that explains the nature of, or even the existence of, football matches, teapots, or jumbo-jet aircraft.". "Consequently physics per se cannot causally determine the outcome of human creativity; rather it creates the 'possibility space' to allow human intelligence to function autonomously."

How to turn a block of Antarctic

How to turn a block of Antarctic ice into a giant neutrino detector. "To turn the ice into a telescope, all you have to do is drill an array of 80 holes half a meter across by 2.5km deep using a very powerfull jet of hot water. Then lower a string of 60 optical detectors into each hole before they refreeze, conect them up to some powerful computer analysers and you are good to go."

A selection of personal letters written by Richard Feynman

A selection of personal letters written by Richard Feynman.

Astronomers may have detected the formation of a black hole

Astronomers may have detected the formation of a black hole. "A faint visible-light flash moments after a high-energy gamma-ray burst likely heralds the merger of two dense neutron stars to create a relatively low-mass black hole."

Mad Physics is a neat science education

Mad Physics is a neat science education site run by a couple of high school students.

The Oh-My-God particle is a proton with

The Oh-My-God particle is a proton with the energy of a slow-pitched baseball. And it's moving so fast that after travelling for a year, it would only be a few nanometers behind a photon travelling at the speed of light.

"Fads, fashions and dramatic shifts in public

"Fads, fashions and dramatic shifts in public opinion all appear to follow a physical law: one of the laws of magnetism". "Michard and Bouchaud checked this prediction against their model and found that the trends in birth rates and cellphone usage in European nations conformed quite accurately to this pattern. The same was true of the rate at which clapping died away in concerts."

A near perfect Einstein Ring found

A near perfect Einstein Ring found. Close galaxies can act as a lens for farther galaxies, focusing the distant light with an "Einstein Ring".

Some bacteria in Africa beat Fermi to

Some bacteria in Africa beat Fermi to the first stable nuclear reactor on Earth by almost 2 billion years. The bacteria enriched the uranium into a critical mass and the flow of water through the reactor kept the reaction going for millions of years.

Brian Greene on Albert Einstein's miracle year,

Brian Greene on Albert Einstein's miracle year, his discovery of the photoelectric effect, and his uneasiness with quantum mechanics.

Genius by James Gleick

This seems familiar:

It made Feynman think wistfully about the days before the future of science had begun to feel like his mission -- the days before physicists changed the universe and became the most potent political force within American science, before institutions with fast-expanding budgets began chasing nuclear physicists like Hollywood stars. He remembered when physics was a game, when he could look at the graceful narrowing curve in three dimensions that water makes as it streams from a tap, and he could take the time to understand why.

Dark Sun: The Making of the Hydrogen Bomb by Richard Rhodes

Rhodes' followup to The Making of the Atomic Bomb (for which he won a Pulitzer), while not as tight a narrative as its predecessor, was more interesting to me because I was less familiar with the story. In particular, the Soviet espionage effort during WWII was fascinating.