A classical and quantum mechanical generalized second law of thermodynamics in cosmology implies constraints on the effective equation of state of the universe in the form of energy conditions, obeyed by many known cosmological solutions, forbids certain cosmological singularities, and is compatible with entropy bounds. This second law is based on the conjecture that causal boundaries and not o...

The performances of solar cells and thermoelectricmaterials are governed by thermodynamics. The material properties of these have temperature dependence due to thermal expansions of lattices and an effect of electron–phonon coupling etc. The temperature-dependent energy levels has been included in statisticalmechanics, naturally requiring a rectification of the second law of thermodynamics with...

Recent results of quantum field theory on a curved spacetime suggest that extremal black holes are not thermal objects and that the notion of zero temperature is ill-defined for them. If this is correct, one may have to go to a full semiclassical theory of gravity, including backreaction, in order to make sense of the third law of black hole thermodynamics. Alternatively it is possible that we ...

A shower cooling tower (SCT) operates without fill because of salt decomposition on the fill that leads to deterioration of conventional cooling tower performance. This study presents a two-dimensional mathematical model for energy and exergy analysis of multi-diameter droplets and air interaction along with the height of the forced draft SCT, to predict the exit condition of water droplet for ...

We consider the generalized second law of black hole thermodynamics in the light of quantum information theory, in particular information erasure and Landauer’s principle (namely, that erasure of information produces at least the equivalent amount of entropy). A small quantum system outside a black hole in the Hartle-Hawking state is studied, and the quantum system comes into thermal equilibriu...

Thermodynamics is the old science that describes the flow of energy in systems with many atoms. Works started by Carnot, Kelvin and Clausius showed that these laws are very general. This universality led to the formulation of the first and second law of thermodynamics, that apply to a vast amount of systems, such as gases and crystals. During half a century there was still a problem with the ap...

One loop field theory calculations of free energies quite often yield violations of the stability conditions usually associated with the thermodynamic second law. Perhaps the best known example involves the equation of state of black holes. Here, it is pointed out that the Casimir force between two parallel conducting plates also violates a thermodynamic stability condition normally associated ...

We propose a formulation of stochastic thermodynamics for systems subjected to nonequilibrium constraints (i.e. broken detailed balance at steady state) and furthermore driven by external time-dependent forces. A splitting of the second law occurs in this description leading to three second-law-like relations. The general results are illustrated on specific solvable models. The present paper us...