Speaker
Mark Van Raamsdonk
Description
I will describe how the standard tools of holography might be used to define microscopic models of big-bang cosmology. I discuss local'' models where a bubble of the cosmological spacetime is embedded in an asymptotically AdS spacetime, andglobal'' models where the full spacetime is encoded in some auxiliary degrees of freedom. While the gravitational effective field theories arising from holographic models have negative cosmological constant, generic cosmological solutions have scalar fields evolving on cosmological time scales that can give late time acceleration. If a model of this type describes nature, a generic prediction is a decreasing dark energy. We present evidence that such a decrease is suggested by supernova and BAO data.
