Results 21 to 30 of about 166,374,925 (284)
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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Does Quantum Electrodynamics Have an Arrow of Time? [PDF]
, 2005 Quantum electrodynamics is a time-symmetric theory that is part of the electroweak interaction, which is invariant under a generalized form of this symmetry, the PCT transformation.
Atkinson, David, David Atkinson
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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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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 +2 more
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Maxwell’s Demon in Quantum Mechanics
Entropy, 2020 Maxwell’s Demon is a thought experiment devised by J. C. Maxwell in 1867 in order to show that the Second Law of thermodynamics is not universal, since it has a counter-example. Since the Second Law is taken by many to provide an arrow of time, the
Orly Shenker, Meir Hemmo
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, 2022 Since the 19th century, time and entropy have come together. In particular, entropy was found to be the key of the so-called “arrow of time” — the distinction between the past and future directions of time is given by the direction in which entropy ...
Lopez, Cristian
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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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Energies, 2022 Based on the square heat-generation body (HGB) with “arrow-shaped” high-thermal-conductivity channel (HTCC) model established in the previous literature, we performed multi-objective optimization (MOO) with maximum temperature difference (MTD ...
Hongwei Zhu +4 more
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Pre-Big-Bang Black-Hole Remnants and Past Low Entropy
Universe, 2018 Dark matter could be composed by black-hole remnants formed before the big-bang era in a bouncing cosmology. This hypothetical scenario has implications on the issue of the arrow of time: it upsets a common attribution of past low entropy to the state of
Carlo Rovelli, Francesca Vidotto
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