Energy Layers and Quasi-Superradiant Heat Engines of Schwarzschild Black Holes

Abstract

We examine Schwarzschild black holes within the framework of gravitational thermodynamics, introducing an ``energy layer'' picture for black-hole mass-energy and exploring a possible energy-extraction mechanism termed ``quasi-superradiance.'' Building on the standard relations for Hawking temperature and Bekenstein--Hawking entropy, we formalize energy layers via quasi-local radial energy accounting (e.g.\ integrating an effective local energy density over spherical shells) and connect this bookkeeping to the free energy $\FHelm=M-\TH \SBH$. We then extend the entropy correction ansatz with explicit series inversion and derive higher-order expansions for $\TH(M)$ and $\FHelm(M)$, including logarithmic and inverse-mass terms. To enhance mathematical transparency, we add intermediate derivations, lemma/theorem statements, and appendices. The quasi-superradiant mechanism is framed as a Carnot-like thought experiment powered by the Tolman temperature gradient between the near-horizon region and infinity; we show that the generalized second law enforces the Carnot bound and yields integrated maximum-work inequalities. Throughout, we stress that the proposal is heuristic and intended as a consistency-checked framework for discussion rather than a claim of definitive new physics.