Paper CCLXIII: Cosmological Bloch Map — Pandey 2026 Entropic Backreaction as the T_2*/T_2 Decomposition of Sump Relaxation, with Free Parameters Absorbed by the sigma_T2* = 1/8 Anchor

Pandey (arXiv:2605.28797, 2026) proposes an entropic-backreaction framework in which dissipation of configuration entropy during nonlinear structure formation simultaneously enhances the late-time expansion rate and suppresses gravitational clustering, addressing the H_0 and S_8 tensions in a single thermodynamic mechanism. The construction is presented as parameter-free but contains two implicit phenomenological dials: a timescale alpha (units of time) parametrising the entropic energy density rho_S = -alpha dotS_c/V, and a dimensionless coupling gamma governing matter-entropic energy exchange Q = gamma rho_S H. Pandey performs no fit to data (his line 1062). We observe that his modified growth equation delta_dotdot + (2H + Gamma) delta_dot - 4 pi G rho_m delta = 0 with Gamma = gamma (rho_S/rho_m) H is structurally identical to the Bloch growth equation of nuclear magnetic resonance, identifying 1/T_2 with 2H (intrinsic friction), 1/T_2-prime with Gamma (inhomogeneity dephasing), and 1/T_2* with 2H + Gamma (apparent). Within the One-Octonion Brane-Bulk framework, both Bloch timescales carry geometric origin: T_2 maps to T_sump,global = 72.65 Gyr (Paper XXIX); T_2* maps to T_sump,local = 60.84 Gyr (Paper XXXV); the local/global split IS the Hubble tension (CCXLVII Section Q1). Pandey's alpha and gamma absorb into OOB primitives: alpha to T_sump, and gamma rho_S/rho_m <= sigma_T2* (1+w_bare) = (1/8)(1 - 4/pi^2) = 0.0743, where the cap derives from three independent e_7-anchor restrictions on graviton source content at the T_2* horizon (CCXLVII Section 10). The OOB Hubble-tension prediction (1+w_obs) = 7.43% at z=0 matches the observed 8.31% (Riess-Planck)/Planck split to 11%, and the implied growth-rate suppression Delta f/f ~ -3.7% is consistent with KiDS-1000. CCXLVII attains chi^2 = 17.18 vs LambdaCDM 49.01 across 19 DESI DR2 bins with zero free parameters. The Bloch map supplies Pandey with the microphysical origin he flags as missing (his lines 1004-1011), revealing his framework as the Shannon-information re-expression of a special case of CCXLVII. Clinical-cosmology bridge: cosmological T_2*/T_2 is the same kind of spin-echo distinction that 7T MRI sees in voxels with comparable inhomogeneity content; framework predicts the same Gudermannian f_III = 1 - 4/pi^2 response envelope in matched-inhomogeneity voxels. Framework count: 264 numbered papers. Part of the One-Octonion Brane-Bulk Framework series. Anchor DOI: 10.5281/zenodo.19120873. Community: one-octonion-brane-bulk. Author: Bharathi Dasan Jagadeesan, M.D., University of Minnesota. ORCID: 0000-0002-1143-941X.