4 papers
Irreducible-Mass Balance for Magnetized Null Horizons with an Internal Current Sheet
Remo Ruffini, Giorgio Sonnino
We begin with a general question: how does the irreducible mass of a magnetized black hole change when the horizon is not stationary? The null Raychaudhuri equation gives an exact…
Irreducible-Mass Growth and Extractable Energy in a Self-Gravitating Blandford-Znajek Engine
Remo Ruffini, Giorgio Sonnino
Wang recently constructed a self-gravitating split-monopole Blandford-Znajek engine and obtained its secular horizon mass and angular-momentum loss rates. We determine the previous…
Entropy, Gravity, and an Apparent Violation of the Second Law
Jorge Pinochet, Giorgio Sonnino
An interesting question to explore in physics classes is whether gravity violates the second law of thermodynamics. Standard physics textbooks provide little to no discussion of th…
An Attempt to Derive the Expression of the Constant in the Thermodynamic Uncertainty Relations by a Statistical Model for a Quasi-Ideal Nano-Gas
Giorgio Sonnino
In recent work, we have shown that fundamental quantities such as the total entropy production, the thermodynamic variables conjugate to the thermodynamic forces, and the Glansdorf…