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81.
We carry out a careful study of operator algebras associated with Delone dynamical systems. A von Neumann algebra is defined using noncommutative integration theory. Features of these algebras and the operators they contain are discussed. We restrict our attention to a certain C *-subalgebra to discuss a Shubin trace formula.  相似文献   
82.
83.
We derive the basic canonical brackets amongst the creation and annihilation operators for a two (1 + 1)- dimensional (2D) gauge field theoretic model of an interacting Hodge theory where a U(1) gauge field (Aμ) is coupled with the fermionic Dirac fields (ψ and ψ). In this derivation, we exploit the spin-statistics theorem, normal ordering and the strength of the underlying six infinitesimal continuous symmetries (and the concept of their generators) that are present in the theory. We do not use the definition of the canonical conjugate momenta (corresponding to the basic fields of the theory) anywhere in our whole discussion. Thus, we conjecture that our present approach provides an alternative to the canonical method of quantization for a class of gauge field theories that are physical examples of Hodge theory where the continuous symmetries (and corresponding generators) provide the physical realizations of the de Rham cohomological operators of differential geometry at the algebraic level.  相似文献   
84.
We present an algorithm for numerically computing an absolutely continuous invariant measure associated with a piecewiseC 2 expanding mappingS: on a bounded region R N. The method is based on the Galerkin projection principle for solving an operator equation in a Banach space. With the help of the modern notion of functions of bounded variation in multidimension, we prove the convergence of the algorithm.  相似文献   
85.
It is shown that polarized light can be polarization squeezed only if it exhibits sub-Poissonian statistics with the Mandel's Q factor less than − 1/2.  相似文献   
86.
胡利云  范洪义  张智明 《中国物理 B》2013,22(3):34202-034202
For the first time,we derive the compact forms of normalization factors for photon-added(-subtracted) two-mode squeezed thermal states by using the P-representation and the integration within an ordered product of operators(IWOP) technique.It is found that these two factors are related to the Jacobi polynomials.In addition,some new relationships for Jacobi polynomials are presented.  相似文献   
87.
88.
Using the technique of integration within an ordered product of operators we present a convenient approach for introducing the squeezing operator for the entangled states of two entangled particles with different masses. We also introduce one-sided squeezing operators.  相似文献   
89.
From point of view of physics, especially of mechanics, we briefly introduce fractional operators (with emphasis on fractional calculus and fractional differential equations) used for describing intermediate processes and critical phenomena in physics and mechanics, their progress in theory and methods and their applications to modern mechanics. Some authors’ researches in this area in recent years are included. Finally, prospects and evaluation for this subject are made.  相似文献   
90.
We study the transversal spin–spin correlations in the non-equilibrium steady state of the XY chain constructed by coupling a finite cutout of the chain to the two infinite parts to its left and right acting as thermal reservoirs at different temperatures. We prove that the spatial decay of these correlations is at least exponentially fast.  相似文献   
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