Cosmic Acceleration and the notion of Alternative Vacuum in Nash Theory

TL;DR

This paper demonstrates that Nash theory, a quadratic gravity model, can account for late-time cosmic acceleration without exotic matter, and links its vacuum dynamics to a Higgs scalar field with observable implications.

Contribution

It introduces an exact cosmological solution within Nash theory that explains cosmic acceleration without dark energy, and connects vacuum dynamics to Higgs field variations.

Findings

Nash theory can replicate late-time acceleration without exotic matter.

Vacuum dynamics in Nash theory are equivalent to Einstein vacuum plus a Higgs scalar.

Variations in fundamental constants align with quasar spectra analysis.

Abstract

We argue that Nash theory, a quadratic theory of Gravity, can describe a late-time cosmic acceleration without any exotic matter or cosmological constant. The observational viability of an exact cosmological solution of Nash theory is adjudged using a Markov chain Monte Carlo simulation and JLA+OHD+BAO data sets. Departures from standard {\Lambda}CDM cosmology are noted and analyzed. We prove that the Nash vacuum dynamics is equivalent to the dynamics of an Einstein vacuum plus a self-interacting Higgs scalar field, only if a mild evolution of the Higgs Vacuum Expectation Value is allowed. This leads to variations in the mass scales of fundamental particles and the fine structure constant. The variations are found to fit nicely with the analysis of molecular absorption spectra from a series of Quasars.