Cosmological Dynamics of Relativistic MOND

TL;DR

This paper analyzes a relativistic MOND theory's cosmological dynamics using phase space methods, showing it can replicate standard cosmological epochs and align with observations, offering a potential alternative to dark matter models.

Contribution

It introduces a phase space analysis of a relativistic MOND theory, demonstrating its viability and richer background cosmology compared to previous models like TeVeS.

Findings

The theory has a viable sequence of cosmological epochs.

It can mimic the standard cosmological model under specific initial conditions.

The theory aligns with observed CMB and matter power spectra.

Abstract

In this paper, we investigate the recently proposed relativistic theory for MOND using the phase space analysis. Unlike its precedent theory, namely TeVeS, this theory is claimed to agree with the observed Cosmic Microwave Background and matter power spectra. We convert the background cosmological equations of the theory to a set of first-order autonomous equations. Then we explore the corresponding critical points and their physical meaning. This method is powerful in the sense that the cosmological behavior of the model is diagnosed independently of the magnitude of the free parameters of the theory. We show that the theory has a viable sequence of cosmological epochs. Although using specific initial conditions, this theory mimics the standard cosmological model; it provides a richer structure as far as the background cosmology is concerned. This implies that further investigations are required to see if this theory contributes to addressing the current cosmological tensions.