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1.
Dirac's large numbers hypothesis (LNH) is incorporated into kinetic theory, statistical physics, and thermodynamics using the self-consistent formalism of units covariance. The ingeodesic equation and matter creation introduce modifications of the most fundamental laws of the subject. Liouville's theorem no longer holds, the Boltzmann equation is modified, as is theH-theorem. This affects the second law of thermodynamics in that for canonical LNH neither reversible nor adiabatic processes are possible (as expected). A significant result is that the collision terms have the same form as in standard physics. This means that equilibrium distribution functions are identical to those of standard physics, as required for self-consistency with the precepts of LNH. The net effect of LNH is as though all matter in our Universe were weakly coupled to a large heat bath.NAS-NRC Senior Research Associate 1981–1983.  相似文献   

2.
The existence theory for the nonlinear Boltzmann equation is discussed for an infinite region in the spatially homogeneous case. We show that the solution is given by a nonlinear contraction semigroup. It is found that theH-theorem holds and that the system approaches equilibrium.  相似文献   

3.
The approach to and structure of the equilibrium state is studied for a 7-bit lattice gas with biased forward and backward transition rates by means of mean field theory and computer simulations. If the rate constants obey the factorizability and the detailed balance conditions, the occupations of different velocity directions are uncorrelated, anH-theorem is valid, and a nonuniversal equilibrium state exists that depends explicitly on the transition rates. In case the above conditions are not satisfied, theH-theorem is no longer valid, and mean field theory also predicts nontrivial velocity correlations in postcollision states. The simulations are mainly concentrated on the time dependence of pre- and postcollision velocity correlations on a single node, and on slowly increasing fluctuations that might indicate metastable behavior.  相似文献   

4.
This paper considers the linear space-inhomogeneous Boltzmann equation in a convex, bounded or unbounded bodyD with general boundary conditions. First, mildL 1-solutions are constructed in the cutoff case using monotone sequences of iterates in an exponential form. Assuming detailed balance relations, mass conservation and uniqueness are proved, together with anH-theorem with formulas for the interior and boundary terms. Local boundedness of higher moments is proved for soft and hard collision potentials, together with global boundedness for hard potentials in the case of a nonheating boundary, including specular reflections. Next, the transport equation with forces of infinite range is considered in an integral form. Existence of weakL 1-solutions are proved by compactness, using theH-theorem from the cutoff case. Finally, anH-theorem is given also for the infinite-range case.  相似文献   

5.
We try to obtain Born's principle as a result of a subquantum heat death, using classical -theorem and the definition of a proper quantum -theorem, within the framwork of Bohm's theory. We shall show the possibility of solving the problem of action-reaction asymmetry present in Bohm's theory and the arrow of time problem in our procedure.  相似文献   

6.
It is shown how coupling to gauge fields can be used to explain the basic facts concerning holomorphic factorization of the WZW model of two dimensional conformal field theory, which previously have been understood primarily by using conformal field theory Ward identities. We also consider in a similar vein the holomorphic factorization ofG/H coset models. We discuss theG/G model as a topological field theory and comment on a conjecture by Spiegelglas.Research supported in part by NSF Grant PHY86-20266  相似文献   

7.
We present a BGK-type collision model which approximates, by a Chapman-Enskog expansion, the compressible Navier-Stokes equations with a Prandtl number that can be chosen arbitrarily between 0 and 1. This model has the basic properties of the Boltzmann equation, including theH-theorem, but contains an extra parameter in comparison with the standard BGK model. This parameter is introduced multiplying the collision operator by a nonlinear functional of the distribution function. It is adjusted to the Prandtl number.  相似文献   

8.
Shigeru Shinomoto 《Physica A》1982,112(3):466-478
We present a method to derive the H-theorem directly from the (two-body) Bogolubov-Green- Cohen equation. With this method, we can investigate the circumstances under which the equation exhibits monotonous approach to equilibrium. This method suggests also that further coarsegraining in time in some sense is needed for this equation as far as the H-theorem is concerned.  相似文献   

9.
10.
The nonextensive statistical mechanics is extended in the special relativity context through a generalization of HH-theorem. We show that the Tsallis framework is compatible with the second law of the thermodynamics when the nonadditive effects are consistently introduced on the collisional term of the Boltzmann equation. The proof of the HH-theorem follows from using of qq-algebra in the generalization of the molecular chaos hypothesis (Stosszahlansatz). A thermodynamic consistency is possible whether the entropic parameter belongs to interval q∈[0,2]q[0,2].  相似文献   

11.
We extend the Zwanzig projector formalism to coupled systems taking into account the mutual interactions of the reduced density matrices of both systems. In the Born- and Markoff-approximation we end up with a bilinear masterequation for occupation probabilities, in contrast to the usually studied linear equations. We derive theH-theorem for this equation and show that the stationary solution is the canonical or more generally a grand canonical density matrix.  相似文献   

12.
The incorporation of three-body collisions for dissociation/recombination into the Boltzmann equation is discussed. Conditions are assumed such that collisions are completed in the sense of scattering theory, so the collision operator is determined by scattering and reaction cross sections. The resulting equation has anH-theorem, and the equilibrium solution requires the law of mass action in addition to the Maxwellian dependence on momentum. A brief discussion is given of the normal solution and the transport coefficients.This paper is dedicated to Prof. E. G. D. Cohen on the occasion of his 65th birthday.  相似文献   

13.
A localH-theorem is derived for a recently proposed extension of Enskog kinetic theory to a dense model fluid composed of particles with interactions extending beyond a hard core.On leave from: Katedra Fizyki, Uniwersytetu Szczecinskiego, 70-451 Szczecin, Poland.  相似文献   

14.
The a-theorem     
The c-theorem is a profound result applying to statistical mechanical theories or quantum field theories in two dimensions. Such theories may be described by a set of parameters which vary as we increase or decrease the scale on which we observe the system, until we reach a fixed point or critical point where the couplings have fixed values. The c-theorem defines a quantity (the c-function) which always increases (or is constant) with increasing scale and thereby gives a valuable insight into the ‘flows’ of the couplings between fixed points. The a-theorem is a proposed generalisation of the c-theorem to higher dimensions, especially four. In this article, we describe the c-theorem, starting in the simpler statistical mechanical context and then showing how in quantum field theory the theorem is most easily formulated in a curved spacetime. We then sketch how these concepts are applied in the more technically complex scenario of four dimensions.  相似文献   

15.
The maximum entropy formalism is used to investigate the growth of entropy (H-theorem) for an isolated system of hard spheres in an external potential under general boundary geometry. Assuming that only correlations of a finite number of particles are controlled and the rest maximizes entropy, we obtain an H-theorem for such a system The limiting cases such as the modified Enskog equation and linear kinetic theory are discussed.  相似文献   

16.
The classical second law of thermodynamics demands that an isolated system evolves with a nondiminishing entropy. This holds as well in quantum mechanics if the evolution of the energy-isolated system can be described by a unital quantum channel. At the same time, the entropy of a system evolving via a nonunital channel can, in principle, decrease. Here, we analyze the behavior of entropy in the context of the H-theorem. As exemplary phenomena, we discuss the action of a Maxwell demon (MD) operating a qubit and the processes of heating and cooling in a two-qubit system. Further we discuss how small initial correlations between a quantum system and a reservoir affect the entropy increase during the quantum-system evolution.  相似文献   

17.
D. Hubert 《Physica A》1975,83(3):548-560
An H-functional is suggested in terms of the single-particle distribution function governed by the Enskog kinetic equation. It is shown to be restricted to situations near the local equilibrium state. A generalized H-theorem valid for all initial situations is established from the point of view of a master equation for the hard-spheres gas. The thermodynamics of irreversible processes is then discussed in relation to the basic foundations of the kinetic theory of dense gases.  相似文献   

18.
We introduce a dual lifting of unified gauge theories, the first characterized by theisotopies, which are axiom-preserving maps into broader structures with positive-definite generalized units used for the representation of matter under the isotopies of the Poincaré symmetry, and the second characterized by theisodualities, which are anti-isomorphic maps with negative-definite generalized units used for the representation of antimatter under the isodualities of the Poincaré symmetry. We then submit, apparently for the first time, a novel grand unification with the inclusion of gravity for matter embedded in the generalized positive-definite units of unified gauge theories while gravity for antimatter is embedded in the isodual isounit. We then show that the proposed grand unification provides realistic possibilities for a resolution of the axiomatic incompatibilities between gravitation and electroweak interactions due to curvature, antimatter and the fundamental space-time symmetries.  相似文献   

19.
A memory is a physical system for transferring information from one moment in time to another, where that information concerns something external to the system itself. This paper argues on information-theoretic and statistical mechanical grounds that useful memories must be of one of two types, exemplified by memory in abstract computer programs and by memory in photographs. Photograph-type memories work by exploiting a collapse of state space flow to an attractor state. (This attractor state is the initialized state of the memory.) The central assumption of the theory of reversible computation tells us that inany such collapsing, regardless of whether the collapsing proceeds from the past to the future or vice versa, the collapsing must increase the entropy of the system. In concert with the second law, this establishes the logical necessity of the empirical observation that photograph-type memories are temporally asymmetric (they can tell us about the past but not about the future). Under the assumption that human memory is a photograph-type memory, this result also explains why we humans can remember only our past and not our future. In contrast to photograph-type memories, computer-type memories do not require any initialization, and therefore are not directly affected by the second law. As a result, computer memories can be of the future as easily as of the past, even if the program running on the computer is logically irreversible. This is entirely in accord with the well-known temporal reversibility of the process of computation. This paper ends by arguing that the asymmetry of the psychological arrow of time is a direct consequence of the asymmetry of human memory. With the rest of this paper, this explains, explicitly and rigorously, why the psychological and thermodynamic arrows of time are correlated with one another.  相似文献   

20.
A strongH-theorem is proved for the approximate linear kinetic theory of Bawzdziewicz and Cichocki, obtained by truncating a transformed hierarchy of evolution equations. For an ith truncation we define an entropy functional that is strictly increasing in time, unless the ith reduced distribution function depends on position coordinates only. It also follows that the only stationary solution of the linear kinetic theory is the equilibrium solution. In addition, we show that the usual symmetry properties of equilibrium time correlation functions are preserved by the approximate kinetic theory under consideration.On leave of absence from Institute of Physics, Szczecin University, Wielkopolska 15, Szczecin, Poland.  相似文献   

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