Results 41 to 50 of about 69,539 (295)

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
doaj   +1 more source

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
doaj   +1 more source

Black-Hole Uncertainty Entails an Intrinsic Time Arrow. a Note on the Hawking-Penrose Controversy [PDF]

, 1999
Any theory that states that the basic laws of physics are time-symmetric must be strictly deterministic. Only determinism enables time reversal of entropy increase. A contradiction therefore arises between two statements of Hawking.
't Hooft, Avshalom C. Elitzur, Dolev, Elitzur, Elitzur, Elitzur, Elitzur, Elitzur, Finkelstein, Ghirardi, Hawking, Hawking, Hawking, Hawking, Hawking, Hawking, Penrose, Penrose, Preskill, Price, Shahar Dolev, Unruh   +21 more
core   +4 more sources

The holographic space-time and black hole remnants as dark matter

Physics Letters B, 2022
The holographic space-time approach to inflation provides a well defined and self-contained framework to study the early universe. Based on a quasi-local quantum gravity theory generalizing string theory beyond AdS backgrounds, it addresses fundamental ...
Aurélien Barrau
doaj   +1 more source

Comment on `Quantum resolution to the arrow of time dilemma' [PDF]

, 2009
Recently, a substantial amount of debate has grown up around a proposed quantum resolution to the `arrow of time dilemma' that is based on the role of classical memory records of entropy-decreasing events.
Jennings, David, Rudolph, Terry
core   +2 more sources

Deflation at Turnaround for Oscillatory Cosmology [PDF]

, 2006
It is suggested that dark energy in a brane world can help reconcile an infinitely cyclic cosmology with the second law of thermodynamics. A cyclic cosmology is described, in which dark energy with constant equation of state leads to a turnaround at ...
Baum, Lauris, Frampton, Paul H.
core   +5 more sources

About some Entropy Aspects of Dissipative Systems [PDF]

Theoretical and Applied Economics, 2006
This paper is aspiring to get a logical explanation on the entropy velocity (i.e. on the entropy acceleration) in a Universe “endowed” with a dissipative system.
Emil Dinga
doaj   +1 more source

Vacuum structure for expanding geometry [PDF]

, 1999
We consider gravitational wave modes in the FRW metrics in a de Sitter phase and show that the state space splits into many unitarily inequivalent representations of the canonical commutation relations.
Albrecht A, Alfinito E, Alhassid Y, Boyanowski D, Bratteli O, Celeghini E, De Filippo S, E Alfinito, Eboli O, Eboli O, Feshbach H, G Vitiello, Grishchuk L P, Hawking S W, Hawking S W, Hawking S W, Hawking S W, Johansson A E I, Lindblad G, Martellini M, Misner W, Ojima I, Penrose R, Perelomov A M, Prokopec T, R Manka, Sewell G L, Solomon A I, Takahashi Y, Umezawa H, Umezawa H, Vitiello G, Wald R M, Wald R M   +33 more
core   +3 more sources

Fidelity Mechanics: Analogues of the Four Thermodynamic Laws and Landauer’s Principle

Entropy, 2022
Fidelity mechanics is formalized as a framework for investigating critical phenomena in quantum many-body systems. Fidelity temperature is introduced for quantifying quantum fluctuations, which, together with fidelity entropy and fidelity internal energy,
Huan-Qiang Zhou, Qian-Qian Shi, Yan-Wei Dai   +2 more
doaj   +1 more source

Vacuum Structure and the Arrow of Time

, 2012
We find ourselves in an extended era of entropy production. Unlike most other observations, the arrow of time is usually regarded as a constraint on initial conditions. I argue, however, that it primarily constrains the vacuum structure of the theory.
A. Linde, J. D. Barrow, J. D. Bekenstein, Raphael Bousso, W. Fischler   +4 more
core   +2 more sources