Brane with variable tension as a possible solution to the problem of the late cosmic acceleration

TL;DR

This paper explores a five-dimensional brane model with variable tension that can explain late cosmic acceleration without dark energy, fitting observational data to estimate model parameters.

Contribution

It introduces a novel variable brane tension model, called chrono-brane, inspired by tracker scalar fields, and constrains it using multiple cosmological observations.

Findings

The model's parameter n is estimated to be approximately 6.19.

The variable tension generates a dark energy-like term in the Friedmann equation.

The model is consistent with current observational data and explains late-time acceleration.

Abstract

Braneworld models have been proposed as a possible solution to the problem of the accelerated expansion of the Universe. The idea is to dispense the dark energy (DE) and drive the late-time cosmic acceleration with a five-dimensional geometry. Here, we investigate a brane model with variable brane tension as a function of redshift called chrono-brane. We propose the polynomial $\lambda=(1+z)^{n}$ function inspired in tracker-scalar-field potentials. To constrain the $n$ exponent we use the latest observational Hubble data from cosmic chronometers, Type Ia Supernovae from the full JLA sample, baryon acoustic oscillations and the posterior distance from the cosmic microwave background of Planck 2015 measurements. A joint analysis of these data estimates $n\simeq6.19$ which generates a DE-like or cosmological-constant-like term, in the Friedmann equation arising from the extra dimensions. This model is consistent with these data and can drive the Universe to an accelerated phase at late times.