Forecasting constraints on quintessential inflation from future generation of galaxy and CMB surveys

Abstract

We investigate the constraining power of future CMB and galaxy surveys on models of quintessential inflation realized within the framework of $\alpha$-attractors. We analyze how these future datasets will probe the parameter space of $\alpha$-attractor quintessential inflation, specifically the inflationary potential parameters. Our results demonstrate that the synergy between CMB-S4, LiteBIRD, and Euclid can significantly tighten the bounds on the model parameters, achieving forecasted $1\sigma$ uncertainties of $\alpha=2\pm 0.17$, $n_s=0.965\pm 0.0014$, $\ln(10^{10}A_s)=3.0447\pm 0.0029$ for the CMB+GC$_{sp}$ case. This level of sensitivity will enable us to discriminate between different realizations of quintessential inflation and test the attractor behavior characteristic of these models.