Non-Canonical Volume-Form Formulation of Modified Gravity Theories and Cosmology

TL;DR

This paper explores a novel formalism using non-canonical spacetime volume-forms in modified gravity theories, offering new insights into cosmological phenomena like dark energy, dark matter, and early universe dynamics.

Contribution

It introduces a non-canonical volume-form approach to modified gravity, unifying various cosmological models and addressing key issues such as dark sector interactions and force suppression.

Findings

Unified description of dark energy and dark matter via a scalar 'darkon'

Models with dynamical Higgs mechanism influenced by gravity

Suppression of fifth force without fine-tuning

Abstract

A concise description is presented of the basic features of the formalism of non-canonical spacetime volume-forms and its application in modified gravity theories and cosmology. The well known unimodular gravity theory appears as a very special case. Concerning the hot issues facing cosmology now, we specifically briefly outline the construction of: (a) unified description of dark energy and dark matter as manifestations of a single material entity -- a special scalar field "darkon"; (b) quintessential models of universe evolution with a gravity-"inflaton"-assisted dynamical Higgs mechanism -- dynamical suppression/generation of spontaneous electroweak gauge symmetry breaking in the "early"/"late" universe; (c) unification of dark energy and dark matter with diffusive interaction among them; (d) mechanism for suppression of 5-th force without fine-tuning.