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31.
本文在无生命、物质和科学三个限制的前提下讨论“信息”到底是什么.依次论证:(1)自然科学没有能力度量信息的“质”,只能讨论信息的“量”;(2)“信息熵”只是度量信息“量”的概念;(3)在无生命的物质科学领域内,信息熵完全等价于Boltzmann熵,对应于实验中的热熵;(4)运用Occam剃刀原理,信息熵和Boltzmann熵两个名词只能留下其中的任意一个;(5)“熵”取决于体系的微观状态总数,即最终取决于热运动引起的分子核骨架的动态变化.于是,在无生命、物质和科学三个限制的领域内“信息”只是望文生义的产物. 相似文献
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《Physics and Chemistry of Liquids》2012,50(2):177-188
Two and three-body correlation entropies of model fluids, in which particles interact each other through the 4th, 6th, 9th and 12th-inverse-power potentials, were calculated from their atomic configurations obtained by molecular dynamics simulations at their freezing points. Besides the soft-core fluid model with the inverse-power potentials, hard-sphere and classical one-component plasma models were employed to provide a comparison with the entropies of the soft-core model. The correlation entropies were plotted as a function of the softness of the potential. These values were also compared with the excess entropies of the hard-sphere and the one-component plasma models at their freezing points. 相似文献
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Robert H. Swendsen 《Physica A》2010,389(15):2898-2901
Although Ludwig Boltzmann was one of the primary founders of the field of statistical mechanics, very few contemporary physicists have actually read his papers. As a result, some of his ideas have been distorted or even lost over the course of time. In this paper, I will discuss some of the reasons for the neglect of Boltzmann’s writings and try to reintroduce one of his most important ideas, the definition of entropy. 相似文献
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Jeff Kahn 《Proceedings of the American Mathematical Society》2002,130(2):371-378
For -regular, -vertex bipartite graphs with bipartition , a precise bound is given for the sum over independent sets of the quantity . (In other language, this is bounding the partition function for certain instances of the hard-core model.) This result is then extended to graded partially ordered sets, which in particular provides a simple proof of a well-known bound for Dedekind's Problem given by Kleitman and Markowsky in 1975.
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Siegenthaler's“Correlation Immunity”concept has been improved in this paper.From practical points of view,the new concept is more powerful than the original one in avoid-ing the trade-off between“the order of correlation immunity”and“the linear complexity”of keystreams in cipher system.Bent functions are also introduced into the studies of linear approxima-tion and entropy immunity for feedforward networks.New results and new methods are presentedalso. 相似文献
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Manfred Einsiedler Douglas Lind 《Transactions of the American Mathematical Society》2004,356(5):1799-1831
We investigate algebraic -actions of entropy rank one, namely those for which each element has finite entropy. Such actions can be completely described in terms of diagonal actions on products of local fields using standard adelic machinery. This leads to numerous alternative characterizations of entropy rank one, both geometric and algebraic. We then compute the measure entropy of a class of skew products, where the fiber maps are elements from an algebraic -action of entropy rank one. This leads, via the relative variational principle, to a formula for the topological entropy of continuous skew products as the maximum of a finite number of topological pressures. We use this to settle a conjecture concerning the relational entropy of commuting toral automorphisms.