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101.
Unitarily-invariant linear spaces in C*-algebras 总被引:2,自引:0,他引:2
Characterisations and containment results are given for linear subspaces of a unital C*-algebra that are invariant under conjugation by sets of unitary elements of the algebra. The (unitarily-invariant) linear span of the projections in a simple, unital C*-algebra having non-scalar projections is shown to contain all additive commutators of the algebra and, in certain cases, to be equal to the algebra.
102.
103.
Anna Paolucci 《Proceedings of the American Mathematical Society》1999,127(8):2249-2258
In this paper we deal with braided tensor C*-categories. For every object of the category we associate a C*-algebra denoted by . An analysis of the braiding is carried out by using the conjugate equations. If the braiding is a Hecke symmetry and the -dimension is appropriately chosen, we characterize the C*-algebra as the one generated by the representation given by the Markov trace. This analysis leads to the existence of an action of on . Such actions (Theorem 1) correspond to *-monomorphisms of on which generalize the ones obtained earlier by the author (1997).
104.
We propose a general scheme for the “logic” of elementary propositions of physical systems, encompassing both classical and
quantum cases, in the framework given by Non-Commutative Geometry. It involves Baire*-algebras, the non-commutative version of measurable functions, arising as envelope of the C
*-algebras identifying the topology of the (non-commutative) phase space. We outline some consequences of this proposal in
different physical systems. This approach in particular avoids some problematic features appearing in the definition of physical
states in the standard (W
*-)algebraic approach to classical mechanics. 相似文献
105.
利用全相对论组态相互作用理论方法,研究了类铷W37+离子从基组态3s23p63d104s24p64d经过双激发态(3s23p63d104s24p64d)-1nln′l′(n,n′=4,5)的双电子复合过程,得到了该离子在温度为1~5×104 eV范围内的总双电子复合速率系数。分析比较了不同电子激发的双电子复合速率系数,结果表明:4p电子激发的双电子复合速率系数在低温时给出了主要贡献,而3d的贡献在高温时突出。由于强组态相互作用,两电子一光子跃迁对双电子复合速率系数的贡献不可忽略,其中辐射跃迁4p54d5d5f-4p64f5d的贡献是双激发态4p54d5d5f总的双电子复合速率系数的5%。对双电子复合、辐射复合以及三体复合速率系数的比较表明,在所研究的温度范围内双电子复合速率系数最大。 相似文献
106.
We show that a number of naturally occurring comparison relations on positive elements in a C?-algebra are equivalent to natural comparison properties of their corresponding open projections in the bidual of the C?-algebra. In particular we show that Cuntz comparison of positive elements corresponds to a comparison relation on open projections, that we call Cuntz comparison, and which is defined in terms of—and is weaker than—a comparison notion defined by Peligrad and Zsidó. The latter corresponds to a well-known comparison relation on positive elements defined by Blackadar. We show that Murray-von Neumann comparison of open projections corresponds to tracial comparison of the corresponding positive elements of the C?-algebra. We use these findings to give a new picture of the Cuntz semigroup. 相似文献
107.
《Expositiones Mathematicae》2022,40(4):947-960
In this article we show that the main C*-algebras describing the canonical commutation relations of quantum physics, i.e., the Weyl and resolvent algebras, are in the class of Følner C*-algebras, a class of C*-algebras admitting a kind of finite approximations of Følner type. In particular, we show that the tracial states of the resolvent algebra are uniform locally finite dimensional. 相似文献
108.
Noor Mohammad 《Periodica Mathematica Hungarica》1996,32(3):209-212
It is shown that if the maximal ideal space (A) of a semisimple commutative complete metrizable locally convex algebra contains no isolated points, then every compact multiplies is trivial. In particular, compact multipliers on semisimple commutative Fréchet algebras whose maximal ideal space has no isolated points are identically zero. 相似文献
109.
The paper is devoted to investigations of properties of regular Riesz subspaces and connections between regularity and some topological properties. The problem if a topological closure preserves regularity is solved in the class of discrete Riesz spaces. We also characterize Dedekind complete Riesz spaces possessing the same classes of -regular and regular Riesz subspaces Moreover, various examples of regular and non regular Riesz spaces are presented. 相似文献
110.
Bertrand Monthubert 《Journal of Functional Analysis》2003,199(1):243-286
We associate to any manifold with corners (even with non-embedded hyperfaces) a (non-Hausdorff) longitudinally smooth Lie groupoid, on which we define a pseudodifferential calculus. This calculus generalizes the b-calculus of Melrose, defined for manifolds with embedded corners. The groupoid of a manifold with corners is shown to be unique up to equivalence for manifolds with corners of same codimension. Using tools from the theory of C∗-algebras of groupoids, we also obtain new proofs for the study of b-calculus. 相似文献