10 papers
Transport Determines Spectral Distance in Mesoscopic Thermodynamics
Giorgio Sonnino, Giorgio SONNINO
We derive a distance between thermodynamic states from a positive Hermitian transport tensor within a mesoscopic canonical model. An exact first-order factorization of the evolutio…
Emergent Spinorial Structure in Mesoscopic Irreversible Thermodynamics
Giorgio Sonnino, Giorgio SONNINO
We reconstruct a geometry of thermodynamic coordinates from transport coefficients within a mesoscopic canonical model. Self-adjoint flux observables determine a compatible evoluti…
Gravity, Entropy, and the Second Law: A Pedagogical Perspective
Jorge Pinochet, Giorgio Sonnino
An interesting question for discussion in university physics courses is whether gravity can conflict with the second law of thermodynamics. In this work, we address this question b…
Extreme Kerr Newman Black Holes: Differential Geometry, Symmetry, and the Golden Ratio
Remo Ruffini, Giorgio Sonnino
We investigate the geometry of extreme Kerr-Newman black holes and its role in selecting distinct black hole states. Motivated by Smarr's question of what physical information is e…
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…
Surface Geometry of Some Meaningful Extreme Kerr-Newman Black Holes
Giorgio Sonnino
We address the properties of extremal black holes by considering the Christodoulou-Ruffini/Hawking mass-energy formula. By simple geometrical arguments, we found that the mass/ener…
Entropy of Difference
Pasquale Nardone
Here, we propose a new tool to estimate the complexity of a time series: the entropy of difference (ED). The method is based solely on the sign of the difference between neighborin…