I stand alone in the elevator, right in the middle, equidistant from the four walls. Before the doors close, a woman enters. Unconsciously, I move over to make room for her. We stand side by side with equal amounts of space between the two of us and between each of us and the walls of the elevator. On the 12th floor, a man gets on and the woman and I slide slightly to the side and to the back, maximizing the space that each of us occupies in the elevator. At the 14th floor, another man gets on. The man in front steps to the back center and the woman and I move slightly toward the front, forming a diamond shape that again maximizes each person's distance from the elevator walls and the people next to them.
It reminds me of cell division in an embryo or the arrangement of atoms in a molecule. Just as the cells and atoms know how to position themselves for maximum efficiency at a minimum size, humans know how to balance the need to collectively occupy an enclosed area and give each person his/her own space.
Update: Stewart sends in a link to Scott Snibbe's Boundary Functions, an art project which makes explicit a person's social space among others:
Boundary Functions is realized as a set of lines projected from overhead onto the floor which divide each person in the gallery from one another. With one person in the gallery there is no response. When two are present, there is a single line drawn halfway between them segmenting the room into two regions. As each person moves, this line dynamically changes, maintaining an even distance between the two. With more than two people, the floor becomes divided into cellular regions, each with the mathematical quality that all space within the region is closer to the person inside than any other.
