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51.
Strongly correlated systems far from equilibrium can exhibit scaling solutions with a dynamically generated weak coupling. We show this by investigating isolated systems described by relativistic quantum field theories for initial conditions leading to nonequilibrium instabilities, such as parametric resonance or spinodal decomposition. The nonthermal fixed points prevent fast thermalization if classical-statistical fluctuations dominate over quantum fluctuations. We comment on the possible significance of these results for the heating of the early Universe after inflation and the question of fast thermalization in heavy-ion collision experiments. 相似文献
52.
53.
Munguia-Lopez Jose G. Juarez Rodrigo Muñoz-Sandoval Emilio Kalixto-Sanchez Marco A. Kinsella Joseph Matthew De Leon-Rodriguez Antonio 《Journal of nanoparticle research》2019,21(8):1-15
Journal of Nanoparticle Research - Workers are increasingly exposed to nanoparticles, mostly via inhalation. Respiratory protection is recommended as an additional control measure. Particulate... 相似文献
54.
Meccanica - The acoustic dispersion properties of monodimensional waveguide filters can be assessed by means of the simple prototypical mechanical system made of an infinite stack of periodic... 相似文献
55.
Ricerche di Matematica - This paper provides an account of results and methods from the theory of infinite groups admitting only finitely many normalizers of subgroups with a given property. Some... 相似文献
56.
Transport in Porous Media - The 4th order Darcy–Bénard eigenvalue problem for the onset of thermal convection in a 3D rectangular porous box is investigated. We start from a recent 2D... 相似文献
57.
Let Ω be a vector space over a finite field with q elements. Let G denote the general linear group of automorphisms of Ω and let us consider the left regular representation
associated with the natural action of G on the set X of linear subspaces of Ω. In this paper we study a natural basis B of the algebra EndG(L
2(X)) of intertwining maps on L
2(X). By using a Laplacian operator on Grassmann graphs, we identify the kernels in B as solutions of a basic hypergeometric difference equation. This provides two expressions for these kernels. One in terms
of the q-Hahn polynomials and the other by means of a Rodrigues type formula. Finally, we obtain a useful product formula for the
mappings in B. We give two different proofs. One uses the theory of classical hypergeometric polynomials and the other is supported by
a characterization of spherical functions in finite symmetric spaces. Both proofs require the use of certain associated Radon
transforms. 相似文献
58.
Marco Matone 《Foundations of Physics Letters》2002,15(4):311-328
We suggest that quantum mechanics and gravity are intimately related. In particular, we investigate the quantum Hamilton–Jacobi equation in the case of two free particles and show that the quantum potential, which is attractive, may generate the gravitational potential. The investigation, related to the formulation of quantum mechanics based on the equivalence postulate, is based on the analysis of the reduced action. A consequence of this approach is that the quantum potential is always non-trivial even in the case of the free particle. It plays the role of intrinsic energy and may in fact be at the origin of fundamental interactions. We pursue this idea, by making a preliminary investigation of whether there exists a set of solutions for which the quantum potential can be expressed with a gravitational potential leading term which alone would remain in the limit 0. A number of questions are raised for further investigation. 相似文献
59.
Anders Björner Andreas Paffenholz Jonas Sjöstrand Günter M. Ziegler 《Discrete and Computational Geometry》2005,34(1):71-86
In 1992 Thomas Bier presented a strikingly simple method to produce a
huge number of simplicial (n – 2)-spheres on 2n vertices, as deleted
joins of a simplicial complex on n vertices with its combinatorial
Alexander dual.
Here we interpret his construction as giving the poset of all the
intervals in a boolean algebra that “cut across an ideal.” Thus we
arrive at a substantial generalization of Bier’s construction: the
Bier posets Bier(P, I) of an arbitrary bounded poset P of
finite length. In the case of face posets of PL spheres this yields
cellular “generalized Bier spheres.” In the case of Eulerian or
Cohen–Macaulay posets P we show that the Bier posets Bier(P, I)
inherit these properties.
In the boolean case originally considered by Bier, we show that all the
spheres produced by his construction are shellable, which yields “many
shellable spheres,” most of which lack convex realization.
Finally, we present simple explicit formulas for the g-vectors of
these simplicial spheres and verify that they satisfy a strong form of
the g-conjecture for spheres. 相似文献
60.