Exact cosmological solutions in non-coincidence $f(Q)$-theory

Abstract

We study exact cosmological solutions in $f(Q)$ gravity formulated beyond the coincident gauge, focusing on the non-coincident connection branch $\Gamma_B$. Using a minisuperspace approach, the field equations are recast into an equivalent scalar-tensor form, enabling analytic reconstruction of cosmological models. We obtain exact solutions of particular interest, including de Sitter, scaling, $\Lambda$CDM, Chaplygin gas, generalized Chaplygin gas, and CPL parameterizations. The corresponding scalar potentials and $f(Q)$ functions are derived in closed or parametric form. Our analysis shows that non-coincident $f(Q)$ gravity admits a richer solution space than the coincident case and can describe both early-time inflationary dynamics and late-time acceleration within a unified framework. These results open new directions for testing $f(Q)$ cosmology against observations and exploring its role as a viable alternative to $\Lambda$CDM.