Results 11 to 20 of about 14,076 (249)

Nanothermodynamics: Stable Thermal Equilibrium and Nanoscale Fluctuations [PDF]

Entropy
Nanothermodynamics is the theory describing how large systems subdivide into equilibrium distributions of small subsystems. A key ingredient is Hill’s subdivision potential (E) that ensures adherence to the 1st and 2nd laws of thermodynamics in systems ...
Ralph V. Chamberlin
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Is Time’s Asymmetry Related to Irreversible Processes and the Second Law?

Entropy, 2023
In this article, we start by describing one of the most characteristic properties of time: “time can never decrease”. From this property, numerous authors have concluded that irreversible processes, that always proceed in one direction, must be related ...
Arieh Ben-Naim
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Causality Is an Effect, II

Entropy, 2021
Causality follows the thermodynamic arrow of time, where the latter is defined by the direction of entropy increase. After a brief review of an earlier version of this article, rooted in classical mechanics, we give a quantum generalization of the ...
Lawrence S. Schulman
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Gravitational Entropy and Inflation

Entropy, 2013
The main topic of this paper is a description of the generation of entropy at the end of the inflationary era. As a generalization of the present standard model of the Universe dominated by pressureless dust and a Lorentz invariant vacuum energy (LIVE ...
Øystein Elgarøy, Øyvind Grøn
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Wormholes and the thermodynamic arrow of time

Physical Review Research, 2020
In classical thermodynamics, heat cannot spontaneously pass from a colder system to a hotter system, which is called the thermodynamic arrow of time. However, if the initial states are entangled, the direction of the thermodynamic arrow of time may not ...
Zhuo-Yu Xian, Long Zhao
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How many universes are necessary for an ice cream to melt? [PDF]

Serbian Astronomical Journal, 2003
We investigate a quantitative consequence of the Acausal-Anthropic approach to solving the long-standing puzzle of the thermo dynamical arrow of time.
Ćirković Milan M.
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Gravitational Entropy and the Second Law of Thermodynamics

Entropy, 2015
The spontaneous violation of Lorentz and diffeomorphism invariance in a phase near the big bang lowers the entropy, allowing for an arrow of time and the second law of thermodynamics. The spontaneous symmetry breaking leads to
John W. Moffat
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Cosmological Time, Entropy and Infinity

Entropy, 2017
Time is a parameter playing a central role in our most fundamental modelling of natural laws. Relativity theory shows that the comparison of times measured by different clocks depends on their relative motion and on the strength of the gravitational ...
Clémentine Hauret, Pierre Magain, Judith Biernaux   +2 more
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On Quantum Entropy

Entropy, 2022
Quantum physics, despite its intrinsically probabilistic nature, lacks a definition of entropy fully accounting for the randomness of a quantum state. For example, von Neumann entropy quantifies only the incomplete specification of a quantum state and ...
Davi Geiger, Zvi M. Kedem
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Where Was Past Low-Entropy?

Entropy, 2019
Where was the past low-entropy of the early universe located? Contrary to some popular answers, I argue that that the dominant source of low-entropy is the fact that a single degree of freedom, the scale factor, was not at equilibrium.
Carlo Rovelli
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