# Reconstructing Gravity on Cosmological Scales

## TL;DR

This paper uses data-driven methods within the Effective Field Theory framework to reconstruct and compare gravitational and Dark Energy models on cosmological scales, showing some models can address the Hubble tension.

## Contribution

It introduces a novel data-driven reconstruction approach for modified gravity and Dark Energy models using the EFT framework, enhancing understanding of their properties and data implications.

## Key findings

- Some models alleviate the Hubble constant discrepancy.
- Reconstructed theories show a preference over the standard model.
- The approach constrains model functions across cosmic time.

## Abstract

We present the data-driven reconstruction of gravitational theories and Dark Energy models on cosmological scales. We showcase the power of present cosmological probes at constraining these models and quantify the knowledge of their properties that can be acquired through state of the art data. This reconstruction exploits the power of the Effective Field Theory approach to Dark Energy and Modified Gravity phenomenology, which compresses the freedom in defining such models into a finite set of functions that can be reconstructed across cosmic times using cosmological data. We consider several model classes described within this framework and thoroughly discuss their phenomenology and data implications. We find that some models can alleviate the present discrepancy in the determination of the Hubble constant as inferred from the cosmic microwave background and as directly measured. This results in a statistically significant preference for the reconstructed theories over the standard cosmological model.