Tests of standard cosmology in Horava gravity, Bayesian evidence for a closed universe, and the Hubble tension

We consider some background tests of standard cosmology in the context of Ho.rava gravity with different scaling dimensions for space and time, which has been proposed as a renormalizable, higher-derivative, Lorentzviolating quantum gravity model without ghost problems. We obtain the very strong and strong Bayesian evidences for our two cosmology models A and B, respectively, depending on the choice of parametrization based on Ho.rava gravity, against the standard, spatially-flat, LCDM cosmology model based on general relativity. An MCMC analysis with the observational data, including BAO, shows (a) preference of a closed universe with the curvature density parameter Omega(k) = -0.005 +/- 0.001, -0.004(-0.001)(+0.003), (b) reduction of the Hubble tension with the Hubble constant H-0 = 71.4(-0.9)(+1.2), 69.5(-0.9)(+1.6) km s(-1) Mpc(-1) for the models A, B, respectively, and also (c) a positive result on the discordance problem. We comment on some possible further improvements for the cosmic-tension problem by considering the more complete early-universe physics, based on the Lorentz-violating standard model with anisotropic space-time scaling, consistently with Ho.rava gravity, as well as the observational data which are properly adopted for the closed universe.

Automated summary

We consider background tests of standard cosmology in the context of Ho.rava gravity and obtain strong Bayesian evidences for our cosmology models A and B, suggesting a possible closed universe with curvature density parameter and reducing the Hubble tension.