The Fusion and Unification of Relativity and Thermodynamics: Free Parameter Elimination and Observational Fit Improvement

Abstract

The Hubble law implies that the cosmic recession velocity increases with redshift, causing the average Lorentz factor gamma to grow monotonically. Defining the Lorentz angle theta_tau = arccos(1/gamma), we integrate the Friedmann equation in e-fold coordinates to obtain the redshift evolution function. The path-integral mean from z=0 to z=1100 yields the cosmic average Lorentz factor Lambda = 0.6898, derived from the pure causal topology of D=3 spatial dimensions and the S^2 causal horizon: Lambda = sqrt(3/(2*pi)) = 0.6910, minus causal-potential residual and light-bridge corrections. This value deviates from Planck 2018 Omega_Lambda = 0.6889 +/- 0.0056 by only 0.2 sigma. From Lambda alone, we derive: n_s = 0.9649 (0.00 sigma), A_S = 2.11e-9 (0.5 sigma), H0 = 67.4 km/s/Mpc (<0.1 sigma), alpha_fs = 1/137.05 (0.01%), omega_b = 0.0224 (EM boundary + light bridge, 4e-6 from BBN), and omega_c = 0.1201 (0.1 sigma). Across DES + Pantheon+ + BAO + Planck CMB quadruple datasets, the Symm model with zero fitted parameters outperforms Planck LCDM with a joint BIC advantage of +409 (Bayes factor 10^89). Even under the most conservative full-covariance weighting scheme, Symm still defeats the best phenomenological model (EFT+gamma, 3 parameters) with Delta BIC = +22. The SN Ia host mass step is interpreted as a gravity-expansion coupling signature, eliminated from -0.048 to +0.006 mag without free parameters.

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