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141.
Yasuyuki Kawahigashi 《Communications in Mathematical Physics》2002,226(2):269-287
We study the recent construction of subfactors by Rehren which generalizes the Longo–Rehren subfactors. We prove that if
we apply this construction to a non-degenerately braided subfactor N⊂M and α±-induction, then the resulting subfactor is dual to the Longo–Rehren subfactor M⊗M
opp⊂R arising from the entire system of irreducible endomorphisms of M resulting from αplusmn;-induction. As a corollary, we solve a problem on existence of braiding raised by Rehren negatively. Furthermore, we generalize
our previous study with Longo and Müger on multi-interval subfactors arising from a completely rational conformal net of factors
on S
1 to a net of subfactors and show that the (generalized) Longo–Rehren subfactors and α-induction naturally appear in this context.
Received: 11 September 2001 / Accepted: 7 October 2001 相似文献
142.
143.
Julio Castellanos 《Mathematische Zeitschrift》2002,239(4):777-802
We consider complete ideals supported on finite sequences of infinitely near points, in regular local rings with dimensions
greater than two. We study properties of factorizations in Lipman special *-simple complete ideals. We relate it to a type
of proximity, linear proximity, of the points, and give conditions in order to have unique factorization. Several examples
are presented.
Received: 2 February 2000 / in final form: 14 March 2001 / Published online: 18 January 2002 相似文献
144.
145.
146.
Possible Loss and Recovery of Gibbsianness¶During the Stochastic Evolution of Gibbs Measures 总被引:1,自引:1,他引:0
A.C.D. van Enter R. Fernández F. den Hollander F. Redig 《Communications in Mathematical Physics》2002,226(1):101-130
We consider Ising-spin systems starting from an initial Gibbs measure ν and evolving under a spin-flip dynamics towards a
reversible Gibbs measure μ≠ν. Both ν and μ are assumed to have a translation-invariant finite-range interaction. We study
the Gibbsian character of the measure νS(t) at time t and show the following:
(1) For all ν and μ, νS(t) is Gibbs for small t.
(2) If both ν and μ have a high or infinite temperature, then νS(t) is Gibbs for all t > 0.
(3) If ν has a low non-zero temperature and a zero magnetic field and μ has a high or infinite temperature, then νS(t) is Gibbs for small t and non-Gibbs for large t.
(4) If ν has a low non-zero temperature and a non-zero magnetic field and μ has a high or infinite temperature, then νS(t) is Gibbs for small t, non-Gibbs for intermediate t, and Gibbs for large t.
The regime where μ has a low or zero temperature and t is not small remains open. This regime presumably allows for many different scenarios.
Received: 26 April 2001 / Accepted: 10 October 2001 相似文献
147.
Alexander Krasnosel'skii Dmitrii Rachinskii 《NoDEA : Nonlinear Differential Equations and Applications》2002,9(1):93-115
We consider autonomous systems with a nonlinear part depending on a parameter and study Hopf bifurcations at infinity. The
nonlinear part consists of the nonlinear functional term and the Prandtl--Ishlinskii hysteresis term. The linear part of the
system has a special form such that the close-loop system can be considered as a hysteresis perturbation of a quasilinear
Hamiltonian system. The Hamiltonian system has a continuum of arbitrarily large cycles for each value of the parameter. We
present sufficient conditions for the existence of bifurcation points for the non-Hamiltonian system with hysteresis. These
bifurcation points are determined by simple characteristics of the hysteresis nonlinearity. 相似文献
148.
F.E. SalmanN. Shash H. Abou El-HadedM.K. El-Mansy 《Journal of Physics and Chemistry of Solids》2002,63(11):1957-1966
AC conductivity and dielectric studies on vanadium phosphate glasses doped with lithium have been carried out in the frequency range 0.2-100 kHz and temperature range 290-493 K. The frequency dependence of the conductivity at higher frequencies in glasses obeys a power relationship, σac=Aωs. The obtained values of the power s lie in the range 0.5≤s≤1 for both undoped and doped with low lithium content which confirms the electron hopping between V4+ and V5+ ions. For doped glasses with high lithium content, the values of s≤0.5 which confirm the domination of ionic conductivity. The study of frequency dependence of both dielectric constant and dielectric loss showed a decrease with increasing frequency while they increase with increasing temperature. The results have been explained on the basis of frequency assistance of electron hopping besides the ionic polarization of the glasses. The bulk conductivity increases with increasing temperature whereas decreases with increasing lithium content which means a reduction of the V5+. 相似文献
149.
Claudia-Elisabeth Wulz 《Czechoslovak Journal of Physics》2002,52(3):C155-C170
The principal physics goals of the Compact Muon Solenoid experiment under construction at the Large Hadron Collider at CERN in Geneva are reviewed. Procedures to search for the Standard Model Higgs boson, supersymmetric Higgses and other supersymmetric particles are described. 相似文献
150.
Matroid bundles, introduced by MacPherson, are combinatorial analogues of real vector bundles. This paper sets up the foundations
of matroid bundles. It defines a natural transformation from isomorphism classes of real vector bundles to isomorphism classes
of matroid bundles. It then gives a transformation from matroid bundles to spherical quasifibrations, by showing that the
geometric realization of a matroid bundle is a spherical quasifibration. The poset of oriented matroids of a fixed rank classifies
matroid bundles, and the above transformations give a splitting from topology to combinatorics back to topology. A consequence
is that the mod 2 cohomology of the poset of rank k oriented matroids (this poset classifies matroid bundles) contains the free polynomial ring on the first k Stiefel-Whitney classes. 相似文献