# $\alpha$-attractor dark energy in view of next-generation cosmological surveys

## TL;DR

Next-generation cosmological surveys will significantly improve constraints on $\alpha$-attractor dark energy models, potentially linking early universe inflation with late-time cosmic acceleration.

## Contribution

This study evaluates the constraining power of upcoming surveys on $\alpha$-attractor dark energy models, highlighting their potential to test unified inflation and dark energy frameworks.

## Key findings

- S4CMB + LSST + SNIa will nearly tenfold improve the FoM.
- Future surveys can effectively probe models connecting early and late acceleration.
- Constraints on $w_0 - w_a$ parameters will be substantially tightened.

## Abstract

The $\alpha$-attractor inflationary models are nowadays favored by CMB Planck observations. Their similarity with canonical quintessence models motivates the exploration of a common framework that explains both inflation and dark energy. We study the expected constraints that next-generation cosmological experiments will be able to impose for the dark energy $\alpha$-attractor model. We systematically account for the constraining power of SNIa from WFIRST, BAO from DESI and WFIRST, galaxy clustering and shear from LSST and Stage-4 CMB experiments. We assume a tensor-to-scalar ratio, $10^{-3} < r < 10^{-2}$, which permits to explore the wide regime sufficiently close, but distinct, to a cosmological constant, without need of fine tunning the initial value of the field. We find that the combination S4CMB + LSST + SNIa will achieve the best results, improving the FoM by almost an order of magnitude; respect to the S4CMB + BAO + SNIa case. We find this is also true for the FoM of the $w_0 - w_a$ parameters. Therefore, future surveys will be uniquely able to probe models connecting early and late cosmic acceleration.