• Corpus ID: 119454275

M-theory observables for cosmological space-times

  title={M-theory observables for cosmological space-times},
  author={T.Banks and W.Fischler},
We discuss the construction of the analog of an S-matrix for space-times that begin with a Big-Bang and asymptote to an FRW universe with nonnegative cosmological constant. When the cosmological constant is positive there are many such S-matrices, related mathematically by gauge transformations and physically by an analog of the principle of black hole complementarity. In the limit of vanishing $\Lambda$ these become (approximate) Poincare transforms of each other. Considerations of the initial… 
String Propagation in the Presence of Cosmological Singularities
We study string propagation in a spacetime with positive cosmological constant, which includes a circle whose radius approaches a finite value as |t|??, and goes to zero at t = 0. Near this
Quantum Gravity In De Sitter Space
We discuss some general properties of quantum gravity in De Sitter space. It has been argued that the Hilbert space is of finite dimension. This suggests a macroscopic argument that General
The fate of four dimensions
In gravitational theories with extra dimensions, it is argued that the existence of a positive vacuum energy generically implies catastrophic instability of our four-dimensional world. The most
Asymptotic states of the bounce geometry
We consider the question of asymptotic observables in cosmology. We assume that string theory contains a landscape of vacua, and that metastable de Sitter regions can decay to a zero cosmological
Cosmology and the S matrix
We study conditions for the existence of asymptotic observables in cosmology. With the exception of de Sitter space, the thermal properties of accelerating universes permit arbitrarily long
Can black holes exist in an accelerating universe
This letter deals with an analysis of the space-time static metric that corresponds to a quintessential state equation with constant characteristic parameter. Following a procedure parallel to as it
Big Bangs and Bounces on the Brane
In view of our accelerating universe, one of the outstanding theoretical issues is the absence of a quantum-gravitational description of de Sitter space. Although speculative, an intriguing
From big bang to big crunch and beyond
We study a quotient Conformal Field Theory, which describes a 3+1 dimensional cosmological spacetime. Part of this spacetime is the Nappi-Witten (NW) universe, which starts at a ``big bang''