Inflation and Holography in String Theory

TL;DR

This paper explores how inflationary space-time can be represented holographically in string theory, proposing that such states are described by density matrices rather than pure states, and discusses the challenges involved.

Contribution

It introduces a holographic description of inflation in string theory using density matrices and analyzes the difficulties in modeling inflation within this framework.

Findings

Inflationary patches are described by density matrices in the dual theory.

Implementations on deformed AdS/CFT models show the complexity of holographic inflation.

Inflation remains elusive to string theory due to fundamental conceptual challenges.

Abstract

The encoding of an inflating patch of space-time in terms of a dual theory is discussed. Following Bousso's interpretation of the holographic principle, we find that those are generically described not by states in the dual theory but by density matrices. We try to implement this idea on simple deformations of the AdS/CFT examples, and an argument is given as to why inflation is so elusive to string theory.