Gravity and Spacetime Fluctuations
We know that Einstein's General Relativity is incomplete, as gravity must somehow be quantum mechanical. I study spacetime fluctuations due to the quantum nature of spacetime.
Inflation is the classic example where quantum effects in the early Universe have imprinted themselves on large scale structure, in the form of metric fluctuations. For example, I studied how an instability in the potential of the Standard Model Higgs boson could impact the successful predictions of inflation, by creating creating a negative energy vacuum patch that grows to devour spacetime. And I am constantly looking for hints of dark matter imprinting itself on the structure and evolution of the Universe.
In a different direction, it has generally been thought that, because of the low energies of experiments relative to the Planck scale, that it will be impossible to see experimental signatures of quantum gravity in the laboratory. We have been considering whether this common lore is true in the context of holography. At the moment, we are confirming that the effects observed in Minkowski space hold in the context of AdS/CFT.