The null-brane space-time provides a simple model of a big crunch/big bang singularity. A non-perturbative definition of M-theory on this space-time was recently provided using matrix theory. We derive the fermion couplings for this matrix model and study the leading quantum effects. These effects include particle production and a time-dependent potential. Our results suggest that as the null-b...

We consider a picture in which the transition from a big crunch to a big bang corresponds to the collision of two empty orbifold planes approaching each other at a constant non-relativistic speed in a locally flat background space-time, a situation relevant to recently proposed cosmological models. We show that p-brane states which wind around the extra dimension propagate smoothly and unambigu...

We consider quantum field theory on a spacetime representing the Big Crunch/Big Bang transition postulated in ekpyrotic or cyclic cosmologies. We show via several independent methods that an essentially unique matching rule holds connecting the incoming state, in which a single extra dimension shrinks to zero, to the outgoing state in which it re-expands at the same rate. For free fields in our...

a Department of Physics and Astronomy, University of Southern California, Los Angeles, CA 90089-2535, USA b Perimeter Institute for Theoretical Physics, Waterloo, ON N2L 2Y5, Canada c Department of Physics and School of Earth and Space Exploration, Arizona State University, Tempe, AZ 85287-1404, USA d Department of Physics and Princeton Center for Theoretical Physics, Princeton University, Prin...