Black Hole Thermodynamics from Macroscopic Vacuum Elasticity

For the past fifty years, the physical foundations of black hole (BH) thermodynamics have remained widely contested because their original derivations rest at the theoretical intersection of general relativity and quantum field theory (QFT). This work provides an alternative macroscopic formulation by treating the physical vacuum in and around a BH as an elastic continuum strained by the presence of mass. Utilizing Hooke’s law of elasticity, we find that the radial strain at the event horizon of every Schwarzschild BH saturates at the same constant value. Under this principle of universal maximum strain, the laws of BH thermodynamics can be formulated within macroscopic continuum mechanics. This dispenses with the conventional QFT derivation in curved spacetime, paralleling the recent macroscopic descriptions of the Casimir effect. Our calculations are carried out using the Reformulated Planck System (RPS), which relies exclusively on Planck’s constant h. This h-native approach prevents the dimensional contamination of 3D continuum mechanics caused by the 2D geometric factor inherently embedded in Dirac’s reduced constant ℏ, a pivotal misstep first recognized in the iconic definitions of the fine-structure constant α and the gravitational coupling constant αg, which long precluded the identification of the α-dependence of the weak coupling constant αw=α. In BH thermodynamics, this RPS-based approach yields higher Hawking temperatures and lower Bekenstein entropies, both by a factor of 2π.