Physicists find way to ‘see’ extra dimensions

February 5, 2007 | Source: KurzweilAI

Physicists at the University of Wisconsin-Madison have devised an approach that may help unlock the hidden shapes of alternate dimensions of the universe.

A computer-generated rendering of a possible six-dimensional geometry similar to those studied by UW-Madison physicist Gary Shiu. Image: courtesy Andrew J. Hanson, Indiana University

A computer-generated rendering of a possible six-dimensional geometry similar to those studied by UW-Madison physicist Gary Shiu. Image: courtesy Andrew J. Hanson, Indiana University

A new study demonstrates that the shapes of extra dimensions can be “seen” by deciphering their influence on the radiation released by the violent birth of the universe 13 billion years ago. The method, published today (Feb. 2) in Physical Review Letters, provides evidence that physicists can use experimental data to discern the nature of these elusive dimensions, and may provide a long-sought foundation for measuring this previously immeasurable aspect of string theory.

Their approach is based on the idea that the six tiny dimensions had their strongest influence on the universe when it itself was a tiny speck of highly compressed matter and energy –that is, in the instant just after the big bang.

Lacking the requisite time machine, they used the next-best thing: a map of cosmic energy released from the big bang. The energy, captured by satellites such as NASA’s Wilkinson Microwave Anisotropy Probe (WMAP), has persisted virtually unchanged for the last 13 billion years, making the energy map basically “a snapshot of the baby universe.”

To learn how to read telltale signs of the six-dimensional geometry from the cosmic microwave background radiation map, they worked backward. Starting with two different types of mathematically simple geometries, called warped throats, they calculated the predicted energy map that would be seen in the universe described by each shape. When they compared the two maps, they found small but significant differences between them.

Their results show that specific patterns of cosmic energy can hold clues to the geometry of the six-dimensional shape.