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1.
For each [0, 1] we consider the Dirichlet form
and the associated Dirichlet operator
for the Gibbs measure of quantum unbounded spin systems interacting via superstable and regular potential. The Gibbs measure is related to the Gibbs state of the system via a (functional) Euclidean integral procedure. The configuration space for the spin systems is given by
We formulate Dirichlet forms in the framework of rigged Hilbert spaces which are related to the space . Under appropriate conditions on the potential, we show that the Dirichlet operator
is essentially self-adjoint on the domain of smooth cylinder functions. We give sufficient conditions on the potential so that the corresponding Gibbs measure is uniformly log-concave (ULC). This property gives the spectral gap of the Dirichlet operator
at the lower end of the spectrum. Furthermore, we prove that under the conditions of (ULC), the unique Gibbs measure satisfies the log-Sobolev inequality (LS). We use an approximate argument used in the study of the same subjects for loop spaces, which in turn is a modification of the method originally developed by S. Albeverio, Yu. G. Kondratiev, and M. Röckner. 相似文献
2.
A. Bartl W. Majerotto B. Mösslacher N. Oshimo 《Zeitschrift fur Physik C Particles and Fields》1991,52(4):677-684
We present a detailed study of
and
and the subsequent decays of
,
, and
at the LHC
. We explore the relevant supersymmetry parameter range. We calculate the cross sections as well as the rates for interesting signatures such as the production of one or two leptons on the lepton side. 相似文献
3.
We show that the Ashtekar-Isham extension
of the configuration space of Yang-Mills theories
is (topologically and measure-theoretically) the projective limit of a family of finite dimensional spaces associated with arbitrary finite lattices.These results are then used to prove that
is contained in a zero measure subset of
with respect to the diffeomorphism invariant Ashtekar-Lewandowski measure on
. Much as in scalar field theory, this implies that states in the quantum theory associated with this measure can be realized as functions on the extended configuration space
. 相似文献
4.
S. B. Shlosman 《Communications in Mathematical Physics》1989,125(1):81-90
We consider the 2-dimensional Ising model with ferromagnetic nearest neighbour interaction at inverse temperature. LetS
N
=
t
be the total magnetization inside anN×N square box,
per
be the Gibbs state in with periodic b.c., andm() be the spontaneous magnetization. We show the existence of the limit
相似文献
5.
Roger Decker Marek Nowakowski Apostolos Pilaftsis 《Zeitschrift fur Physik C Particles and Fields》1993,57(2):339-347
We calculate the dominant three body Higgs decays,HW
+
W
–(Z
0, ) and
, in the Standard Model. We find that the branching ratios of these decays are of the order of few percent for large Higgs masses. We comment on the behaviour of the partial decay width
below the
threshold. Numerical results of the following three body top decays,tW
+
b(,g, Z
0) andtW
+
bH, are also given. We discuss the feasibility of observing these Higgs and top decays at future high energy colliders. 相似文献
6.
Horng-Tzer Yau 《Communications in Mathematical Physics》1996,181(2):367-408
Let
denote the grand canonical Gibbs measure of a lattice gas in a cube of sizeL with the chemical potential and a fixed boundary condition. Let
be the corresponding canonical measure defined by conditioning
on
. Consider the lattice gas dynamics for which each particle performs random walk with rates depending on near-by particles. The rates are chosen such that, for everyn andL fixed,
is a reversible measure. Suppose that the Dobrushin-Shlosman mixing conditions holds for
forall chemical potentials . We prove that
for any probability densityf with respect to
; here the constant is independent ofn orL andD denotes the Dirichlet form of the dynamics. The dependence onL is optimal.Research partially supported by U.S. National Science Foundations grant 9403462, Sloan Foundation Fellowship and David and Lucile Packard Foundation Fellowship. 相似文献
7.
James D. Edmonds Jr. 《Foundations of Physics》1978,8(5-6):439-444
The 2-by-2 Pauli matrix algebra is used to write the 1-by-4 Dirac field in anequivalent 2-by-2 matrix . The current 4-vectors
and *µ are then compared and the latter is shown to not be easily interpretable as a probability density, and also tocontain
. 相似文献
8.
D. Kastler M. Mebkhout G. Loupias L. Michel 《Communications in Mathematical Physics》1972,27(3):195-222
With
aC*-algebra with unit andgG
g
a homomorphic map of a groupG into the automorphism group ofG, the central measure
of a state of
is invariant under the action ofG (in the state space of
) iff is -invariant. Furthermore if the pair {
,G} is asymptotically abelian, is ergodic iff
is ergodic. Transitive ergodic states (corresponding to transitive central measures) are centrally decomposed into primary states whose isotropy groups form a conjugacy class of subgroups. IfG is locally compact and acts continuously on
, the associated covariant representations of {
, } are those induced by such subgroups. Transitive states under time-translations must be primary if required to be stable. The last section offers a complete classification of the isotropy groups of the primary states occurring in the central decomposition of euclidean transitive ergodic invariant states. 相似文献
9.
The theorem that each derivation of aC*-algebra
extends to an inner derivation of the weak-operator closure (
)– of
in each faithful representation of
is proved in sketch and used to study the automorphism group of
in its norm topology. It is proved that the connected component of the identity in this group contains the open ball of radius 2 with centerl and that each automorphism in extends to an inner automorphism of (
)–.Research conducted with the partial support of the NSF and ONR. 相似文献
10.
Total electron emission from metals due to the impact of multiply charged ions, , may significantly influence quantitative measurements of ion current in corpuscular diagnostics. The value of (/q) was determined for Xe ions impacting clean polycrystalline copper as a function of ion charge state
and of ion kinetic energy,
keV/q, i.e. in the energy region up to
keV/amu, where there is a lack of such data. For highly charged projectile ions,
was found to have a clear minimum as a function of E
i. With decreasing charge state of the projectile ion this minimum shifts to a lower energy and becomes shallower. This observation is in agreement with compiled results of other authors. Limits for values of
are estimated and discussed. 相似文献
11.
Bramson M. Calderoni P. De Masi A. Ferrari P. Lebowitz J. Schonmann R. H. 《Journal of statistical physics》1986,45(5-6):905-920
We consider a model of stochastically interacting particles on , where each site is assumed to be empty or occupied by at most one particle. Particles jump to each empty neighboring site with rate/2 and also create new particles with rate 1/2 at these sites. We show that as seen from the rightmost particle, this process has precisely one invariant distribution. The average velocity of this particle V() then satisfies
–1/2V()
as. This limit corresponds to that of the macroscopic density obtained by rescaling lengths by a factor
1/2 and letting. This density solves the reaction-diffusion equation
, and under Heaviside initial data converges to a traveling wave moving at the same rate
. 相似文献
12.
Couch and Torrence suggest that the vacuum Einstein equations admit a larger class of asymptotically flat solutions than those exhibiting the peeling property. Starting with the assumption that
, (d/dr)
and (/x
A
)
, wherex
A
(A = 2, 3) are angular coordinates, they show that
, where 1 2 and 1<0;
, where 2 1 and 1< 1; and 4 and 3 peel as they would under the stronger peeling conditions. The Winicour-Tamburino energy-momentun and angular momentum integrals for these solutions, in general, diverge. In fact, since Couch and Torrence determine only the radial dependence of the solution, it is not clear that the solutions are well defined. We find that the stronger assumption
, (d/dr)
, and (/x
A
)
does result in well-defined solutions for which both the energy-momentum and angular momentum intergrals are not only finite but result in the same expressions as are obtained for peeling space-times. This assumption appears to be the minimal assumption that is necessary for investigating outgoing radiation at null infinity.In part based on a dissertation by Stephanie Novak and submitted to Syracuse University in partial fulfillment of the requirement for the Ph.D. degree. 相似文献
13.
C. Quesne 《International Journal of Theoretical Physics》1999,38(7):1905-1923
GLh(n) ×GLh(m)-covariant (hh)-bosonic[or (hh)-fermionic] algebras
are built in terms of thecorresponding Rh and
-matrices by contracting theGLq(n) ×
-covariant q-bosonic (or q-fermionic) algebras
, = 1, 2.When using a basis of
wherein theannihilation operators are contragredient to thecreation ones, this contraction procedure can be carried out for any n, m values. Whenemploying instead a basis wherein the annihilationoperators, like the creation ones, are irreducibletensor operators with respect to the dual quantumalgebra Uq(gl(n))
, a contraction limit only exists forn, m {1, 2, 4, 6, . . .}. For n = 2, m = 1, andn = m = 2, the resulting relations can be expressed interms of coupled (anti)commutators (as in the classical case), by usingUh(sl(2)) [instead of s1(2)] Clebsch-Gordancoefficients. Some Uh(sl(2)) rank-1/2irreducible tensor operators recently constructed byAizawa are shown to provide a realization of
(2, 1). 相似文献
14.
Elliott H. Lieb 《Communications in Mathematical Physics》1980,77(2):127-135
A general formulation is given of Simon's Ising model inequality:
whereB is any set of spins separating from . We show that
b
can be replaced by
b
A
whereA is the spin system insideB containing . An advantage of this is that a finite algorithm can be given to compute the transition temperature to any desired accuracy. The analogous inequality for plane rotors is shown to hold if a certain conjecture can be proved. This conjecture is indeed verified in the simplest case, and leads to an upper bound on the critical temperature. (The conjecture has been proved in general by Rivasseau. See notes added in proof.)Work partially supported by U.S. National Science Foundation grant PHY-7825390 A01 相似文献
15.
E. Maël 《Zeitschrift fur Physik C Particles and Fields》1994,61(1):83-90
The helicity difference of the photon photoproduction process px is calculated using four different polarized proton structure functions. Also discussed are the contributions originating from the Compton cross-section and the subprocesses of
induced by photon structure and fragmentation. Up-quark and gluondominance can be separated by choosing different regions of pseudorapidity and normalized transverse momentumX
T
of the final-state photon. We show, that it is possible to distinguish between the two extreme models of proton spin: polarized gluon vice polarized strange-quark. 相似文献
16.
17.
J. Brenneisen D. Grathwohl M. Lickert R. Ott H. Röpke J. Schmälzlin P. Siedle B. H. Wildenthal 《Zeitschrift für Physik A Hadrons and Nuclei》1995,352(2):149-159
The systematics of-decay modes and radiative widths of highly excited states in28Si has been extended by taking-ray spectra on 60 resonances of the27Al(p,) reaction in the range 1097 keVE
p
4492 keV (12643 keVE
x
15915 keV) and on the24Mg(,) resonances atE
=3355, 3431, 4003 keV (E
x
=12860, 12925, 13 415 keV). The-decay modes of levels in the sub-resonance region (E
x
=10–12.5 MeV) were studied with both the27
A1(p, ) reaction and the27
A1(d, n) reaction at Ed=4,5,6 MeV. Information on radiative widths of levels was obtained by measuring the resonance strengthsS
=(2I+1)
p
/ for 52 resonances of the27Al(p, ) reaction with an emphasis on prospective T=1 states. 相似文献
18.
Matthew M. Seabaugh Ender Suvaci Bhaskar Brahmaroutu Gary L. Messing 《Interface Science》2000,8(2-3):257-267
Single crystals of -alumina with {0001}, {11
and {01
2} orientations were embedded in a matrix of liquid phase sintered alumina to study -alumina single crystal growth in the presence of a calcium aluminosilicate liquid. Growth on the {11
0} and {01
2} surfaces was observed to occur by a diffusion-controlled mechanism while growth on the basal surface was controlled by two-dimensional nucleation. Growth models, which incorporate the change in matrix grain size, were derived and shown to fit the growth kinetics. 相似文献
19.
Neutrinoless double-beta decay within Minimal Supersymmetric Standard Model with gauge mediated supersymmetry breaking is considered. Limits on R-parity breaking constant
coming from non-observability of 0 in 76Ge are found. The dependence of
on different parameters at the messenger scale M are shown, with special attention paid to nuclear part of calculations. We have found that
strongly depends on the effective supersymmetry breaking scale only and deduced limits imposed on this non-standard parameter by the germanium experiment. 相似文献
20.
T. F. Hoang 《Zeitschrift fur Physik C Particles and Fields》1994,62(2):343-347
An analysis of secondary hadrons fromZ
0 (91) decays of the LEP experiments indicates that the scaling of
distributions implies the same temperatureT=0.261 GeV for all the secondaries. The multiplicities ofZ
0,K
0, ,..., and computed with their quark contents and the sameT agree with the data. The ratio of
to the phase-space covered by the rapidity distribution, depends only on the energy,
, fore
+
e
– annihilations and
collisions as well. 相似文献
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