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11.
Erling Størmer 《Communications in Mathematical Physics》1967,5(1):1-22
Groups of *-automorphisms ofC*-algebras and their invariant states are studied. We assume the groups satisfy a certain largeness condition and then obtain results which contain many of those known for asymptotically abelianC*-algebras and for inner automorphisms and traces ofC*-algebras. Our key result is the construction in certain finite cases, where the automorphisms are spatial, of an invariant linear map of theC*-algebra onto the fixed point algebra carrying with it most of the relevant information. 相似文献
12.
13.
Positive linear maps of operator algebras 总被引:5,自引:0,他引:5
Erling Størmer 《Acta Mathematica》1963,110(1):233-278
14.
Geertsma’s analytical method is often used to compute strain and stress changes around a compacting geological reservoir. The present work extends Geertsma’s solution by adding a rigid layer beneath the compacting reservoir. Analytical formulae are presented for all the components of displacement of a point in the subsurface. Our derivation includes the correction of an error found in the paper written by Sharma in 1956. 相似文献
15.
Abstract Infrared spectra of codeposited ethyl benzoate with excess titanium tetrachloride at 80 K revealed a novel 2:1 complex, where the inorganic entity is proposed to be a dimeric, triple bridged titanium tetrachloride unit. The ester is complexed to one of the octahedral titanium units through the carbonyl group. Compared to the 2:2 complex there are νc=o' ν α-C-Oand νTi-O shifts of -40/-47, +4/+24 and +16/17 cm?1, depending on which of the 18O-carbonyl or d5-ethyl isotopic congeners is considered. 相似文献
16.
17.
Let (A,α) be a C*-dynamical system. We introduce the notion of pressure P
α(H) of the automorphism α at a self-adjoint operator H∈A. Then we consider the class of AF-systems satisfying the following condition: there exists a dense α-invariant *-subalgebra
? of A such that for all pairs a,b∈? the C*-algebra they generate is finite dimensional, and there is p=p(a,b)∈ℕ such that [α
j
(a),b]= 0 for |j|≥p. For systems in this class we prove the variational principle, i.e. show that P
α(H) is the supremum of the quantities h
φ(α) −φ(H), where h
φ(α) is the Connes–Narnhofer–Thirring dynamical entropy of α with respect to the α-invariant state φ. If H∈A, and P
α(H) is finite, we show that any state on which the supremum is attained is a KMS-state with respect to a one-parameter automorphism
group naturally associated with H. In particular, Voiculescu's topological entropy is equal to the supremum of h
φ(α), and any state of finite maximal entropy is a trace.
Received: 19 April 2000 / Accepted: 14 June 2000 相似文献
18.
It was conjectured by A. Bouchet that every bidirected graph which admits a nowhere-zero k-flow admits a nowhere-zero 6-flow. He proved that the conjecture is true when 6 is replaced by 216. O. Zyka improved the
result with 6 replaced by 30. R. Xu and C. Q. Zhang showed that the conjecture is true for 6-edge-connected graph, which is
further improved by A. Raspaud and X. Zhu for 4-edge-connected graphs. The main result of this paper improves Zyka’s theorem
by showing the existence of a nowhere-zero 25-flow for all 3-edge-connected graphs. 相似文献
19.
20.
令X=(n1,n2,…,nt),Y=(m1,m2,…,mt)是两个t维递减序列.如果对所有的j,1≤j≤t,都有∑i=1~j、ni≥∑i=1~j mi以及∑i=1~t ni=∑i=1~t mi,则称X可盖Y,记作X■Y.如果X≠Y,则记作X■Y.本文考虑联图G(n1,n2,…,nt;a)=(Kn1∪n2∪…∪Knt)∨Ka的谱半径,这里n1+n2+…+nt+a=n,(n1,n 相似文献