2026/07/16 by F. Barzi, W. El Hadri, H. El Moumni +2
#gr-qc #hep-th
We study accretion and neutrino-sensitive thermal signatures of a static black hole reconstructed from a three-parameter generalized entropy. The construction is thermodynamic by design: the entropy deformation is not mapped to a radial-coordinate redefinition or to a prescribed Reissner--Nordström-like correction. Instead, the generalized entropy fixes the horizon response factor Ξh=dSG/dS|Sh. The effective exterior geometry is then reconstructed by requiring its surface-gravity temperature to reproduce the generalized thermodynamic temperature. As a result, the metric preserves the horizon area and the Schwarzschild asymptotics, and reduces smoothly to Schwarzschild when Ξh→1. The deformation is controlled by λG=1/Ξh-1, while the integer p≥2 determines the radial localization of the near-horizon correction. We compute the photon sphere, critical shadow scale, circular geodesics, ISCO, Novikov--Thorne flux, disk temperature, radiative efficiency, energy-at-infinity luminosity, a redshifted spectral proxy, and neutrino-sensitive temperature moments. In particular, positive λG moves the photon sphere and ISCO inward, decreases the shadow scale, raises the radiative efficiency, and concentrates the energy release toward the inner disk. By contrast, negative λG produces the opposite trend. Finally, the neutrino sector is modeled conservatively using dimensionless temperature moments instead of a full neutrino-dominated accretion flow or annihilation-deposition calculation. The hierarchy among the n=4, n=6, and n=9 moments reveals that entropy-induced disk deformation becomes increasingly apparent with higher temperature exponents. Thus, observable changes in compact orbits and thin-disk emission can be directly linked to generalized entropy via the horizon response.