Patch dualities and remarks on nonstandard cosmologies

TL;DR

This paper explores dualities among various cosmological models within the patch formalism, revealing how high-energy effects and brane modifications influence their spectra and characteristics.

Contribution

It establishes dualities between inflationary, cyclic, and phantom cosmologies in the context of extra-dimensional brane models, highlighting new features due to modified Friedmann equations.

Findings

Dualities between cosmological models are established within the patch formalism.

Exact dualities for 4D spectra are broken in favor of braneworld counterparts.

Modified Friedmann equations lead to new features in dual solutions.

Abstract

In this paper we establish dualities between inflationary, cyclic/ekpyrotic, and phantom cosmologies within the patch formalism approximating high-energy effects in scenarios with extra dimensions. The exact dualities relating the four-dimensional spectra are broken in favour of their braneworld counterparts; the dual solutions display new interesting features because of the modification of the effective Friedmann equation on the brane. We then address some qualitative issues about phantomlike cosmologies without phantom matter.