Get started
Work

Reheating After the Bounce: The Permitted Temperature Window, Expansion Bookkeeping, and Baryogenesis in the Aldred Frame

Year: 2026
Type: preprint
Abstract: In Einstein-Cartan spin-torsion gravity, the universe in the Aldred frame contracts to the density limit rho_A = 9.72e54 g/cm^3 and re-expands. Companion computations bounded the density at which the observable primordial spectrum is laid down to rho_b <= 2.77e54 g/cm^3 (x_b <= 0.285 at 1 sigma) and showed that the frame's correction at big bang nucleosynthesis (BBN) densities is some fifty orders of magnitude below detectability. This paper prices the epoch between them: reheating, the thermalisation of the bounce's energy into the hot plasma. If a fraction eps_th of the exit energy density thermalises promptly, the reheating temperature is T_reh = eps_th^(1/4) T_max with T_max = 1.045e9 GeV for thermalisation at rho_A and 7.64e8 GeV at the Planck-compatible exit density rho_b. Against the robust BBN floor T_reh >= 4 MeV, the permitted window is open by 11.4 orders of magnitude, and any thermalisation efficiency above 2.16e-47 clears the BBN floor. A reheating epoch ending at 4 MeV contains N_re = 35.4 e-folds for equation of state w = 0 (30.3 for w = 1/6; 26.6 for w = 1/3) and shifts the pivot bookkeeping of the spectrum computation by Delta N_* = -8.85 e-folds in the w = 0 case, which would move an absolute slow-roll prediction of n_s by 0.0106, 2.5 times the Planck uncertainty; the spectrum computation's actual bound nevertheless survives, tightening only from x_b <= 0.285 to x_b <= 0.266. For baryogenesis, the exit must deliver eta = 6.12e-10 after reheating. Electroweak-scale and resonant leptogenesis operating windows fit inside the permitted window, but grand-unified baryogenesis at T ~ 1e16 GeV is excluded at any exit density the frame permits, and hierarchical thermal leptogenesis, which requires T_reh >= 1e9 GeV, is excluded at the Planck-compatible exit (required efficiency 2.94, greater than unity) and survives at the absolute ceiling only for eps_th >= 0.84. All numbers are produced by the deposited compute.py. AI use is disclosed: computational and drafting assistance was provided by Dave, an artificial intelligence system operated by Aldred Industries; the author, William Alexander Aldred, reviewed the computation and takes responsibility for the contents. The author is sole author of record.
DOI: 10.5281/zenodo.24111238
Language: English
Open Access status: green
OpenAlex ID: W7225739661
Cites:
Cited by:
Related to: