With colleagues Bret Underwood and Kathryn Zurek at UW-Madison and Devin Walker at UC-Berkeley, Shiu shows in the new study that the signature patterns from particles called Kaluza-Klein (KK) gravitons can distinguish between different proposed extra-dimensional geometries.
How" Shiu compares the effect to a darkened room in which patterns of sound resonating off the walls can reveal the shape of the room. Similarly, KK gravitons are sensitive to the extra-dimensional shape and, through their behavior and decay, may reveal clues to that shape.
The current study shows that, in simulations, even small geometric variations lead to visible differences in KK graviton signatures, Underwood says.
Based on these results, Shiu says, "At least in principle, one may be able to use experimental data to test and constrain the geometry of our universe."
Last year, Shiu and Underwood reported that clues to dimensional geometries might also be visible in patterns of cosmic radiation left over from the Big Bang. The new work complements the previous approach, they say.
"The more hints we get, the better idea we have about the underlying physics," says Shiu.
Adds Underwood, "If the cosmology and particle physics data agree, it's an indication we're on the right track."
|Contact: Gary Shiu|
University of Wisconsin-Madison