Nonzero spatial curvature in symmetric teleparallel cosmology

We consider the symmetric teleparallel f(Q)-gravity in Friedmann-Lema & icirc;tre-Robertson-Walker cosmology with nonzero spatial curvature. For a nonlinear f(Q) model there exist always the limit of General Relativity with or without the cosmological constant term. The de Sitter solution is always provided by the theory and for the specific models f(A)(Q) similar or equal to Q (a/a-1),f(B)(Q) similar or equal to f(1)Q(a/a-1) and f(C)(Q) similar or equal to Q+ f(1)QlnQ it was found to be the unique attractor. Consequently small deviations from STGR can solve the flatness problem and lead to a de Sitter expansion without introduce a cosmological constant term. This result is different from that given by the power-law theories for the other two scalar of the trinity of General Relativity. What makes the nonlinear symmetric teleparallel theory to stand out are the new degree of freedom provided by the connection defined in the non-coincidence frame which describes the nonzero spatial curvature.

Automated summary

This article investigates the application of symmetric teleparallel f(Q)-gravity in Friedmann-Lemaître-Robertson-Walker cosmology with nonzero spatial curvature. It is found that for a nonlinear f(Q) model, there always exists the limit of General Relativity. The de Sitter solution is identified as the unique attractor, and deviations from STGR can solve the flatness problem.