scholarly journals Entropy Balance in the Expanding Universe: A Novel Perspective

Entropy ◽  
2019 ◽  
Vol 21 (4) ◽  
pp. 406
Author(s):  
Arturo Tozzi ◽  
James F. Peters
Keyword(s):  
Quantum Mechanics ◽  
Second Law Of Thermodynamics ◽  
Quantum Systems ◽  
Second Law ◽  
Quantum Vacuum ◽  
Expanding Universe ◽  
Cosmic Expansion ◽  
Thermodynamic Entropy ◽  
Local Observer ◽  
Relational Mechanism

We describe cosmic expansion as correlated with the standpoints of local observers’ co-moving horizons. In keeping with relational quantum mechanics, which claims that quantum systems are only meaningful in the context of measurements, we suggest that information gets ergodically “diluted” in our isotropic and homogeneous expanding Universe, so that an observer detects just a limited amount of the total cosmic bits. The reduced bit perception is due the decreased density of information inside the expanding cosmic volume in which the observer resides. Further, we show that the second law of thermodynamics can be correlated with cosmic expansion through a relational mechanism, because the decrease in information detected by a local observer in an expanding Universe is concomitant with an increase in perceived cosmic thermodynamic entropy, via the Bekenstein bound and the Laudauer principle. Reversing the classical scheme from thermodynamic entropy to information, we suggest that the cosmological constant of the quantum vacuum, which is believed to provoke the current cosmic expansion, could be one of the sources of the perceived increases in thermodynamic entropy. We conclude that entropies, including the entangled entropy of the recently developed framework of quantum computational spacetime, might not describe independent properties, but rather relations among systems and observers.

scholarly journals Local Observers in an Expanding Universe: Is the Cosmological Constant Correlated with Thermodynamic Entropy?

2018 ◽  
Author(s):  
Arturo Tozzi
Keyword(s):  
Cosmological Constant ◽  
Second Law Of Thermodynamics ◽  
Lower Number ◽  
Second Law ◽  
Quantum Vacuum ◽  
Expanding Universe ◽  
Cosmic Expansion ◽  
Thermodynamic Entropy ◽  
Local Observer ◽  
The Universe

We describe cosmic expansion from the standpoint of an observer’s comoving horizon.  When the Universe is small, the observer detects a large amount of the total cosmic bits, which number is fixed.  Indeed, information, such as energy, cannot be created or destroyed in our Universe, i.e., the total number of cosmic bits must be kept constant, despite the black hole paradox.  When the Universe expands, the information gets ergodically “diluted” in our isotopic and homogeneous Cosmos.  This means that the observer can perceive just a lower number of the total bits, due the decreased density of information in the cosmic volume (or its surrounding surface, according to the holographic principle) in which she is trapped by speed light’s constraints.  Here we ask: how does the second law of thermodynamics enter in this framework?  Could it be correlated with cosmic expansion?  The correlation is at least partially feasible, because the decrease in the information detected by a local observer in an expanding Universe leads to an increase in detected cosmic thermodynamic entropy, via the Bekenstein bound and the Laudauer principle.  Reversing the classical scheme from thermodynamic entropy to information entropy, we suggest that the quantum vacuum’s cosmological constant, that causes cosmic expansion, could be one of the sources of the increases in thermodynamic entropy detected by local observers.

scholarly journals Probability, preclusion and biological evolution in Heisenberg-picture Everett quantum mechanics

2021 ◽  
pp. 2150117
Author(s):  
Mark A. Rubin
Keyword(s):  
Quantum Mechanics ◽  
State Vector ◽  
Biological Evolution ◽  
Second Law Of Thermodynamics ◽  
Quantum Mechanical ◽  
Second Law ◽  
Subjective Experiences ◽  
Everett Interpretation ◽  
Heisenberg Picture ◽  
Physical Laws

The fact that certain “extraordinary” probabilistic phenomena — in particular, macroscopic violations of the second law of thermodynamics — have never been observed to occur can be accounted for by taking hard preclusion as a basic physical law, i.e. precluding from existence events corresponding to very small but nonzero values of quantum-mechanical weight. This approach is not consistent with the usual ontology of the Everett interpretation, in which outcomes correspond to branches of the state vector, but can be successfully implemented using a Heisenberg-picture-based ontology in which outcomes are encoded in transformations of operators. Hard preclusion can provide an explanation for biological evolution, which can in turn explain our subjective experiences of, and reactions to, “ordinary” probabilistic phenomena, and the compatibility of those experiences and reactions with what we conventionally take to be objective probabilities arising from physical laws.

Loss and Dissipation: The RLC Circuit

2021 ◽  
pp. 230-246
Author(s):  
Duncan G. Steel
Keyword(s):  
Quantum Mechanics ◽  
Energy Loss ◽  
Quantum System ◽  
Equations Of Motion ◽  
Quantum Systems ◽  
Quantum Vacuum ◽  
Classical Systems ◽  
Rlc Circuit ◽  
Quantum Behavior ◽  
Continuum Of States

The effects of energy loss or dissipation is well-known and understood in classical systems. It is the source of heat in LCR circuits and in the application of brakes in a vehicle or why a struck bell does not ring indefinitely. Understanding quantum behavior begins with understanding the Hamiltonian for the problem. Classically, loss arises from a coupling of the Hamiltonian for an isolated quantum system to a continuum of states. We look at such a Hamiltonian and develop the equations of motion following the rules of quantum mechanics and find that even in a quantum system, this coupling leads to loss and non-conservation of probability in the otherwise isolated quantum system. This is the Weisskopf–Wigner formalism that is then used to understand the quantum LCR circuit. The same formalism is used in Chapter 15 for the decay of isolated quantum systems by coupling to the quantum vacuum and the resulting emission of a photon.

Thermodynamics, Quantum Physics, and Black Holes

2020 ◽  
pp. 24-39
Author(s):  
John W. Moffat
Keyword(s):  
Black Holes ◽  
Black Hole ◽  
Quantum Mechanics ◽  
Quantum Physics ◽  
Second Law Of Thermodynamics ◽  
Information Loss ◽  
Second Law ◽  
Major Question ◽  
Long Time ◽  
Information Loss Problem

A major question confronting physicists studying black holes was whether thermodynamics applied to them—that is, whether the black holes radiated heat and lost energy. Bekenstein considered heat and thermodynamics important for the interior of black holes. Based on the second law of thermodynamics, Hawking proposed that black holes evaporate over a very long time through what we now call Hawking radiation. This concept contradicts the notion that nothing can escape a black hole event horizon. Quantum physics enters into Hawking’s calculations, and he discovered the conundrum that the radiation would violate quantum mechanics, leading to what is called the information loss problem. These ideas are still controversial, and many physicists have attempted to resolve them, including Russian theorists Zel’dovich and Starobinsky. Alternative quantum physics interpretations of black holes have been proposed that address the thermodynamics problems, including so-called gravastars.

What’s Wrong with This Picture?

2020 ◽  
pp. 1-18
Author(s):  
Jim Baggott
Keyword(s):  
Quantum Mechanics ◽  
Classical Mechanics ◽  
Second Law Of Thermodynamics ◽  
Second Law ◽  
Atoms And Molecules ◽  
Intuitive Appeal ◽  
Light Waves ◽  
Microscopic World ◽  
Physical Principles ◽  
Conceptual Difficulties

Despite its intuitive appeal, classical mechanics is just as fraught with conceptual difficulties and problems of interpretation as its quantum replacement. The problems just happen to be rather less obvious, and so more easily overlooked or ignored. Quantum mechanics was born not only from the failure wrought by trying to extend classical physical principles into the microscopic world of atoms and molecules, but also from the failure of some of its most familiar and cherished concepts. To set the scene and prepare for what follows, this Prologue highlights some of the worst offenders, including: space and time; force and energy; the troublesome concept of mass; light waves and the ether; and atoms and the second law of thermodynamics.

scholarly journals Maxwell’s Demon in Quantum Mechanics

Entropy ◽  
2020 ◽  
Vol 22 (3) ◽  
pp. 269
Author(s):  
Orly Shenker ◽  
Meir Hemmo
Keyword(s):  
Quantum Mechanics ◽  
Thought Experiment ◽  
Classical Mechanics ◽  
Second Law Of Thermodynamics ◽  
Quantum Mechanical ◽  
Second Law ◽  
Arrow Of Time ◽  
Maxwell’S Demon ◽  
Counter Example ◽  
Maxwell's Demon

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 threat to its universality threatens the account of temporal directionality as well. Various attempts to “exorcise” the Demon, by proving that it is impossible for one reason or another, have been made throughout the years, but none of them were successful. We have shown (in a number of publications) by a general state-space argument that Maxwell’s Demon is compatible with classical mechanics, and that the most recent solutions, based on Landauer’s thesis, are not general. In this paper we demonstrate that Maxwell’s Demon is also compatible with quantum mechanics. We do so by analyzing a particular (but highly idealized) experimental setup and proving that it violates the Second Law. Our discussion is in the framework of standard quantum mechanics; we give two separate arguments in the framework of quantum mechanics with and without the projection postulate. We address in our analysis the connection between measurement and erasure interactions and we show how these notions are applicable in the microscopic quantum mechanical structure. We discuss what might be the quantum mechanical counterpart of the classical notion of “macrostates”, thus explaining why our Quantum Demon setup works not only at the micro level but also at the macro level, properly understood. One implication of our analysis is that the Second Law cannot provide a universal lawlike basis for an account of the arrow of time; this account has to be sought elsewhere.

The Second Law of Thermodynamics and Heat Release to the Global Environment by Human Activities

2010 ◽  
Author(s):  
Kau-Fui Vincent Wong
Keyword(s):  
Climate Change ◽  
Global Warming ◽  
Heat Release ◽  
Human Activities ◽  
Second Law Of Thermodynamics ◽  
Global Environment ◽  
Current Work ◽  
Second Law ◽  
Thermodynamic Entropy ◽  
Laws Of Thermodynamics

It is the postulate of the current work that all human activities do add heat to the global environment. The basis used is the concept of thermodynamic entropy and the second law of thermodynamics. It has been discussed and shown that human activities do release heat to the global environment. There is no claim and not the objective in the current work to make any statement about climate change or global warming. It is suggested that all significant human-related activities have been included in the discussion, and hence the proof and deduction. The approach used is in accordance with the manner in which the laws of thermodynamics were derived, which is empirical.

ENTROPY OF A HARMONIC OSCILLATOR IN CONTACT WITH A SQUEEZED RESERVOIR

1991 ◽  
Vol 05 (03) ◽  
pp. 545-562 ◽  
Author(s):  
ROBERT R. TUCCI
Keyword(s):  
Harmonic Oscillator ◽  
Second Law Of Thermodynamics ◽  
Second Law ◽  
Duhem Equation ◽  
First Law Of Thermodynamics ◽  
Random Energy ◽  
Thermodynamic Entropy ◽  
Two Temperatures ◽  
Minimum Uncertainty ◽  
Derivatives Of

We consider a harmonic oscillator (h.o.) in contact with a non-minimum uncertainty squeezed reservoir (but isolated from contact with other non-squeezed reservoirs). We calculate the h.o.’s density matrix and thermodynamic entropy. We interpret the derivatives of the entropy in terms of two temperatures, one for each quadrature of the reservoir. A change in the total (random) energy of the h.o. is shown to equal the sum of changes in the energies of each h.o. quadrature separately (a version of the First Law of thermodynamics). A change in the total entropy of the h.o. system is likewise shown to equal the sum of changes in the entropies of each h.o. quadrature separately (Second Law of thermodynamics). We also present equations that correspond to the so called “Fundamemental equation” and “Gibbs-Duhem equation” for the h.o system under consideration.

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