Kurtosis consistency relation in large-scale structure as a probe of gravity theories

TL;DR

This paper develops kurtosis-based consistency relations from matter density fluctuations to test and constrain alternative gravity theories like DHOST, providing a new observational tool for gravity research.

Contribution

It introduces two independent kurtosis consistency relations specific to DHOST theories, enabling tests of these gravity models using observational data.

Findings

Derived two independent consistency relations for DHOST theories.

Proposed kurtosis relations as a new test for gravity theories.

Potential to constrain model parameters with observational data.

Abstract

Various gravity theories beyond general relativity have been rigorously investigated in the literature such as Horndeski and degenerate higher-order scalar-tensor (DHOST) theories. In general, numerous model parameters are involved in such theories, which should be constrained to test the theories with experiments and observations. We construct the kurtosis consistency relations, calculated based on matter density fluctuations, in which the information of gravity theories is encoded. We derive two independent consistency relations that should hold in the framework of the DHOST theories and argue that such consistency relations would be useful for testing gravity theories.