Observational constraints on Myrzakulov gravity

TL;DR

This paper constrains Myrzakulov $F(R,T)$ gravity models using cosmological data, finding they are statistically comparable to $\\Lambda$CDM and exploring their implications for cosmic evolution and dark energy.

Contribution

It provides observational constraints on Myrzakulov $F(R,T)$ gravity models and compares their fit to cosmological data with standard $\\Lambda$CDM.

Findings

Both models are compatible with data at about 1 sigma.

The dimensionless parameter is constrained near zero, slightly favoring positive values.

Models fit the data well and are statistically equivalent to $\\Lambda$CDM.

Abstract

We use data from Supernovae (SNIa) Pantheon sample, from Baryonic Acoustic Oscillations (BAO), and from cosmic chronometers measurements of the Hubble parameter (CC), alongside arguments from Big Bang Nucleosynthesis (BBN), in order to extract constraints on Myrzakulov $F(R,T)$ gravity. This is a connection-based theory belonging to the Riemann-Cartan subclass, that uses a specific but non-special connection, which then leads to extra degrees of freedom. Our analysis shows that both considered models lead to $\sim 1 \sigma$ compatibility in all cases. For the involved dimensionless parameter we find that it is constrained to an interval around zero, however the corresponding contours are slightly shifted towards positive values. Furthermore, we use the obtained parameter chains so to reconstruct the corresponding Hubble function, as well as the dark-energy equation-of-state parameter, as a function of redshift. As we show, Model 1 is very close to $\Lambda$CDM scenario, while Model 2 resembles it at low redshifts, however at earlier times deviations are allowed. Finally, applying the AIC, BIC and the combined DIC criteria, we deduce that both models present a very efficient fitting behavior, and are statistically equivalent with $\Lambda$CDM cosmology, despite the fact that Model 2 does not contain the latter as a limit.