Mimetic Tensor-Vector-Scalar Cosmology: Incorporating Dark Matter, Dark Energy and Stiff Matter

TL;DR

This paper explores the Mimetic Tensor-Vector-Scalar (MiTeVeS) theory, extending dark matter models to include scalar fields and interactions, resulting in cosmological solutions with dark matter, dark energy, and stiff matter components.

Contribution

It introduces an extended mimetic theory incorporating scalar and vector fields with interactions, revealing new cosmological dynamics and components.

Findings

Conserved Noether current acts as dark matter.

Including interactions yields dark energy and dark matter coupling.

Solutions include dark matter, dark energy, and stiff matter fluids.

Abstract

Phenomenological implications of the Mimetic Tensor-Vector-Scalar theory (MiTeVeS) are studied. The theory is an extension of the vector field model of mimetic dark matter, where a scalar field is also incorporated, and it is known to be free from ghost instability. In the absence of interactions between the scalar field and the vector field, the obtained cosmological solution corresponds to the General theory of Relativity (GR) with a minimally-coupled scalar field. However, including an interaction term between the scalar field and the vector field yields interesting dynamics. There is a shift symmetry for the scalar field with a flat potential, and the conserved Noether current, which is associated with the symmetry, behaves as a dark matter component. Consequently, the solution contains a cosmological constant, dark matter and a stiff matter fluid. Breaking the shift symmetry with a non-flat potential gives a natural interaction between dark energy and dark matter.