A tachyonic extension of the stringy no-go theorem

TL;DR

This paper demonstrates that in string theory models involving tachyons, the universe's inflationary phase cannot smoothly transition to a standard expanding universe, extending the stringy no-go theorem.

Contribution

It introduces a tachyonic extension to the stringy no-go theorem, showing limitations on smooth transitions in string-inspired inflation models.

Findings

Inflationary phase does not connect smoothly to FRW universe.

Provides a simple tachyonic extension of the stringy no-go theorem.

Highlights constraints on string theoretic inflation models.

Abstract

We investigate the tachyon-dilaton-metric system to study the "graceful exit" problem in string theoretic inflation, where tachyon plays the role of the scalar field. From the phase space analysis, we find that the inflationary phase does not smoothly connect to a Friedmann-Robertson-Walker (FRW) expanding universe, thereby providing a simple tachyonic extension of the recently proved stringy no-go theorem.