Unraveling the nature of Gravity through our clumpy Universe

TL;DR

This paper introduces a new cosmological probe using voids and supernovae Ia to test gravity theories across different redshifts, highlighting the potential for future surveys to detect deviations from general relativity.

Contribution

It proposes a novel method combining void catalogs and supernovae data to distinguish between general relativity and modified gravity theories.

Findings

Current data is insufficient to detect deviations from general relativity.

The method can differentiate effects of convergence and peculiar velocities on supernova luminosities.

Future surveys could enable testing gravity theories with this approach.

Abstract

We propose a new probe to test the nature of gravity at various redshifts through large-scale cosmological observations. We use our void catalog, extracted from the Sloan Digital Sky Survey (SDSS, DR10), to trace the distribution of matter along the lines of sight to SNe Ia that are selected from the Union 2 catalog. We study the relation between SNe Ia luminosities and convergence and also the peculiar velocities of the sources. We show that the effects, on SNe Ia luminosities, of convergence and of peculiar velocities predicted by the theory of general relativity and theories of modified gravities are different and hence provide a new probe of gravity at various redshifts. We show that the present sparse large-scale data does not allow us to determine any statistically- significant deviation from the theory of general relativity but future more comprehensive surveys should provide us with means for such an exploration.