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111.
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
112.
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
113.
令Sk 1表示k 1阶星图,φ^*(2k,n)表示2Sk 1的两个k度点分别与路Pn的两个1度点重迭后得到的图.对于1≤i≤2k n=1,用Srq 2^*(i)表示rφ^*(2k,n)的每个分支的第i个顶点依次与Sr 1的r个1度点重迭后得到的新图;Гpq 1^*(i)表示pφ^*(2k,n)的每个分支的第i个顶点及其对称点依次与S2p 1的2p个1度点配对且重迭后得到的新图.我们通过研究这两类新图与一定数目的孤立点组成的并图的伴随多项式的因式分解,证明了上述并图的补图的色等价图的结构定理. 相似文献
114.
We study deformations of invertible bimodules and the behavior of Picard groups under deformation quantization. While K
0-groups are known to be stable under formal deformations of algebras, Picard groups may change drastically. We identify the semiclassical limit of bimodule deformations as contravariant connections and study the associated deformation quantization problem. Our main focus is on formal deformation quantization of Poisson manifolds by star products. 相似文献
115.
LetE andF be two Borel sets of the countable productZ of the two point space {0,1}. Assume thatE andF are invariant sets for the odometer transformationR and thatE andF are of measure zero with respect to the unique finiteR-invariant measure onZ. We show thatE andF areR-orbit equivalent in a strict sense. 相似文献
116.
It has been recognized for some time that when cost-benefit analysis is applied to irreversible environmental decisions, such as that of developing or preserving wilderness land, there can be an option value associated with the preservation decision, which arises when there is future uncertainty with respect to the benefits of development or preservation. In this paper the provenance of option value is examined and it is shown that an important cause is a special kind of uncertainty, viz. the possibility of reversals in direction of the relative valuations of wilderness land and developed land, a property we refer to as ditonicity. It is shown that the more ditonic the relative valuation process the greater the deviance between the certainty-equivalence development policy and the stochastically optimal one, and thus by implication the greater the option value. In the two cases with zero ditonicity, when relative wilderness valuations always increase or always decrease (even though in a stochastic fashion), there is zero option value. The model used assumes that service flows from wilderness and developed land are size-dependent, with future relative values known only in terms of a stochastic process, which can take jumps up or down of the same proportional size, at random times. Development can be partial or total and can occur in impulses at any time over an infinite time horizon. 相似文献
117.
徐利光 《新疆大学学报(理工版)》2005,22(4):416-424
运用C0-半群理论研究一类由可修,可靠的人与机器构成的系统解的渐近性质.首先证明在虚轴上除了0以外其他所有点都属于该算子的豫解集,其次证明0是对应于该系统的主算子及其共轭算子的几何与代数重数为1的特征值,由此推出该系统的时间依赖解当时刻趋向于无穷时强收敛于系统的稳态解. 相似文献
118.
Arthur W. Apter 《Mathematical Logic Quarterly》2007,53(1):78-85
If κ < λ are such that κ is indestructibly supercompact and λ is 2λ supercompact, it is known from [4] that
- {δ < κ | δ is a measurable cardinal which is not a limit of measurable cardinals and δ violates level by level equivalence between strong compactness and supercompactness}
- {δ < κ | δ is a measurable cardinal which is not a limit of measurable cardinals and δ satisfies level by level equivalence between strong compactness and supercompactness}
119.
经典Volterra算子$V$及其伴随算子$V^*$在复空间$L^2[0,1]$中起着关键作用. 关于$V$和$V^*$的线性组合的性质, 我们给出了确保$z_1V+z_2V^*(z_1,z_2\in\mathbb{C})$满足增生性质的等价条件. 本文描述了$(u+iv)I+mV+nV^*(u,v,m,n\in\mathbb{R},m+n\geq0)$数值域的精确表示. 相似文献
120.
The construction of multipartite unextendible product bases(UPBs) is a basic problem in quantum information.We respectively construct two families of 2 × 2× 4 and 2 × 2 × 2 × 4 UPBs of size eight by using the existing four-qubit and five-qubit UPBs.As an application,we construct novel families of multipartite positive-partial-transpose entangled states,as well as their entanglement properties in terms of the geometric measure of entanglement. 相似文献