M-theory observables for cosmological space-times

TL;DR

This paper explores the construction of an S-matrix analog for cosmological space-times with a Big Bang and asymptotic FRW universe, proposing a quantum framework and a new horizon problem solution.

Contribution

It introduces a model for the earliest semiclassical universe state and discusses the construction of an S-matrix for such cosmological scenarios.

Findings

Multiple S-matrices exist for positive cosmological constant, related by gauge transformations.

A quantum treatment of initial states is necessary for a consistent theory.

Proposes a new solution to the horizon problem alternative to inflation.

Abstract

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 state require a quantum treatment of space-time, and some preliminary steps towards constructing such a theory are proposed. In this context we propose a model for the earliest semiclassical state of the universe, which suggests a solution for the horizon problem different from that provided by inflation.