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101.
Francesco Zucconi 《Transactions of the American Mathematical Society》2003,355(10):4045-4059
This article presents some results on the surfaces of general type whose Albanese morphism is a holomorphic fibre bundle.
102.
The thermodynamics of general relativistic systems with boundary, obeying a Hamiltonian constraint in the bulk, is determined
solely by the boundary quantum dynamics, and hence by the area spectrum. Assuming, for large area of the boundary, (a) an
area spectrum as determined by non-perturbative canonical quantum general relativity (NCQGR), (b) an energy spectrum that
bears a power law relation to the area spectrum, (c) an area law for the leading order microcanonical entropy, leading thermal
fluctuation corrections to the canonical entropy are shown to be logarithmic in area with a universal coefficient. Since the
microcanonical entropy also has universal logarithmic corrections to the area law (from quantum space-time fluctuations, as
found earlier) the canonical entropy then has a universal form including logarithmic corrections to the area law. This form
is shown to be independent of the index appearing in assumption (b). The index, however, is crucial in ascertaining the domain
of validity of our approach based on thermal equilibrium. 相似文献
103.
We describe the problem of the equivalence of ensembles at the level of states for classical lattice systems. We discuss circumstances where the vanishing of the specific information gain of a sequence of microcanonical measures with respect to a sequence of grand canonical measures implies the equivalence of ensembles. We give a simple derivation of a criterion for the vanishing of the specific information gain in terms of thermodynamic functions. The proof uses ideas from the theory of large deviations but is self-contained. We show how the criterion works in a simple model of a paramagnet and in the Ising model of a ferromagnet in any dimension but fails in the case of the Curie-Weiss mean-field model. 相似文献
104.
研究奇异系统Hamilton正则方程的形式不变性即Mei对称性,给出其定义、确定方程、限制方程和附加限制方程.研究奇异系统Hamilton正则方程的Mei对称性与Noether对称性、Lie对称性之间的关系,寻求系统的守恒量.给出一个例子说明结果的应用.
关键词:
奇异系统
Hamilton正则方程
约束
对称性
守恒量 相似文献
105.
106.
B. Z. Shavarovskii 《Mathematical Notes》1998,64(5):663-673
The structure of polynomial matrices in connection with their reducibility by semiscalar-equivalent transformations and similarity
transformations to simpler forms is considered. In particular, the canonical form of polynomial matrices without multiple
characteristic roots with respect to the above transformations is indicated. This allows one to establish a canonical form
with respect to similarity for a certain type of finite collections of numerical matrices.
Translated fromMatematicheskie Zametki, Vol. 64, No. 5, pp. 769–782, November, 1998. 相似文献
107.
108.
We investigate the effects of temperature and density on the single-particle and many-particle coefficients as well as on
the structures of homogenous systems in which the particles are assumed to interact via a continuous soft sphere potential
in the microcanonical ensemble. The pair distribution function and therefore the structures of the systems studied are affected
by temperature close to and above the melting point through migrations of atoms from the first shell in the pair distribution
function.
The dynamics of atomic pairs in the short-time regime in liquid aluminium may be said to be governed by the potential of mean
force, which depends on the static structure of liquid Al at all investigated temperatures. A polynomial dependence ofD on density and temperature was observed in contradiction to Arrhenius law. The shear viscosities of the systems studied are
largely nonlinear. It was observed that the soft sphere potential used in our calculations overestimates the Stoke-Einstein
relation. 相似文献
109.
Standard ensemble or particle filtering schemes do not properly represent states of low priori probability when the number of available samples is too small, as is often the case in practical applications. We introduce here a set of parametric resampling methods to solve this problem. Motivated by a general H-theorem for relative entropy, we construct parametric models for the filter distributions as maximum-entropy/minimum-information models consistent with moments of the particle ensemble. When the prior distributions are modeled as mixtures of Gaussians, our method naturally generalizes the ensemble Kalman filter to systems with highly non-Gaussian statistics. We apply the new particle filters presented here to two simple test cases: a one-dimensional diffusion process in a double-well potential and the three-dimensional chaotic dynamical system of Lorenz. 相似文献
110.
Kac introduced the notion of the canonical decomposition for a dimension vector of a quiver. Here we will give an efficient algorithm to compute the canonical decomposition. Our study of the canonical decomposition for quivers with three vertices gives us fractal-like pictures. 相似文献