共查询到20条相似文献,搜索用时 46 毫秒
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The spin-fermion model describes a two level quantum system
(spin 1/2) coupled to finitely many free Fermi gas reservoirs
which are in thermal equilibrium at inverse temperatures β
j
. We consider non-equilibrium initial conditions where not all β
j
are the same. It is known that, at small coupling, the combined system
has a unique non-equilibrium steady state (NESS) characterized by strictly sitive entropy production. In this paper we study
linear response in this NESS and prove the Green-Kubo formula and the Onsager reciprocity relations for heat fluxes generated
by temperature differentials.
Dedicated to Jean Michel Combes on the occasion of his sixtyfifth birthday 相似文献
4.
Roberto Paoletti 《Letters in Mathematical Physics》2006,78(2):189-204
Let (M , ω , J) be a compact and connected polarized Hodge manifold, an isodrastic leaf of half-weighted Bohr–Sommerfeld Lagrangian submanifolds. We study the relation between the Weinstein symplectic structure of and the asymptotics of the the pull-back of the Fubini–Study form under the projectivization of the so-called BPU maps on . 相似文献
5.
Hong-yi Fan J. Chen 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2003,23(3):437-442
Based on the newly constructed Einstein, Podolsky and Rosen (EPR) entangled state representation we introduce macroscopic
classical functions associated with atomic coherent state τ with angular momentum value j. These functions are proportional to the ordinary one-variable Hermite polynomials of order 2j. The corresponding Wigner quasiprobability function for τ in phase space is also derived which turns out to be a two-variable Hermite polynomial H
2j, 2j. In so doing, a new classical-quantum correspondence scheme for angular momentum system is established.
Received 7 August 2002 / Received in final form 14 December 2002 Published online 24 April 2003
RID="a"
ID="a"Work supported by the National Natural Science Foundation of China under grant 10175057.
RID="b"
ID="b"e-mail: fhym@sjtu.edu.en 相似文献
6.
Paolo Aschieri Leonardo Castellani Marija Dimitrijević 《Letters in Mathematical Physics》2008,85(1):39-53
A -product is defined via a set of commuting vector fields , and used in a theory coupled to the fields. The -product is dynamical, and the vacuum solution , reproduces the usual Moyal product. The action is invariant under rigid translations and Lorentz rotations, and the conserved
energy–momentum and angular momentum tensors are explicitly derived.
相似文献
7.
The conformal anomaly and a contribution to the one-loop effective action associated with the product
of the Laplace operators
, p=1,2 acting in irreducible rank 1 symmetric spaces are calculated. The explicit form of the zeta functions and the conformal
anomaly of the stress-energy momentum tensor is derived.
Pis’ma Zh. éksp. Teor. Fiz. 67, No. 3, 166–171 (10 February 1998)
Published in English in the original Russian journal. Edited by Steve Torstveit. 相似文献
8.
Serban Belinschi Amir Dembo Alice Guionnet 《Communications in Mathematical Physics》2009,289(3):1023-1055
We study the asymptotic behavior of the appropriately scaled and possibly perturbed spectral measure of large random real symmetric matrices with heavy tailed entries. Specifically, consider the N × N symmetric matrix whose (i, j) entry is , where (x
ij
, 1 ≤ i ≤ j < ∞) is an infinite array of i.i.d real variables with common distribution in the domain of attraction of an α-stable law, , and σ is a deterministic function. For random diagonal D
N
independent of and with appropriate rescaling a
N
, we prove that converges in mean towards a limiting probability measure which we characterize. As a special case, we derive and analyze
the almost sure limiting spectral density for empirical covariance matrices with heavy tailed entries.
Supported in part by a Discovery grant from the Natural Sciences and Engineering Research Council of Canada and a University
of Saskatchewan start-up grant.
Research partially supported by NSF grant #DMS-0806211. 相似文献
9.
We consider the maximum solution g(t), t ∈ [0, + ∞), to the normalized Ricci flow. Among other things, we prove that, if (M, ω) is a smooth compact symplectic 4-manifold such that and let g(t), t ∈ [0, ∞), be a solution to (1.3) on M whose Ricci curvature satisfies that |Ric(g(t))| ≤ 3 and additionally χ(M) = 3τ (M) > 0, then there exists an , and a sequence of points {x
j,k
∈ M}, j = 1, . . . , m, satisfying that, by passing to a subsequence,
t ∈ [0, ∞), in the m-pointed Gromov-Hausdorff sense for any sequence t
k
→ ∞, where (N
j
, g
∞), j = 1, . . . , m, are complete complex hyperbolic orbifolds of complex dimension 2 with at most finitely many isolated orbifold points. Moreover,
the convergence is C
∞ in the non-singular part of and , where χ(M) (resp. τ(M)) is the Euler characteristic (resp. signature) of M.
The first author was supported by NSFC Grant No.10671097 and the Capital Normal University. 相似文献
10.
Nikolay M. Nikolov Karl-Henning Rehren Ivan Todorov 《Communications in Mathematical Physics》2008,279(1):225-250
The twist two contribution in the operator product expansion of for a pair of globally conformal invariant, scalar fields of equal scaling dimension d in four space–time dimensions is a field V
1 (x1, x2) which is harmonic in both variables. It is demonstrated that the Huygens bilocality of V
1 can be equivalently characterized by a “single–pole property” concerning the pole structure of the (rational) correlation
functions involving the product . This property is established for the dimension d = 2 of . As an application we prove that any system of GCI scalar fields of conformal dimension 2 (in four space–time dimensions)
can be presented as a (possibly infinite) superposition of products of free massless fields. 相似文献
11.
A theory of weak localization responsible for the negative magnetoresistance effect is developed for quantum wells at the
tellurium surface, which retains, in contrast to the
surface considered earlier, a trigonal spectrum distortion with opposite signs near the M and P extrema, with the latter playing the part of states with opposite spins. It is shown that as a result of the motion in momentum
and spin spaces being correlated the spin relaxation due to this distortion is smaller than that for the (0001) surface.
Fiz. Tverd. Tela (St. Petersburg) 39, 1659–1664 (September 1997) 相似文献
12.
B. Paneah 《Russian Journal of Mathematical Physics》2008,15(2):291-296
The new identifying problem is formulated for general linear functional operators
F = Σc
j
F ○ a
j
which significantly generalizes in particular the well-known Ulam stability problem. The results obtained can be very useful
when processing experimental data of any kind as they enable to determine with high precision the structure of a compactly
supported Banach-valued function F by using a rather restricted information concerning
F.
Dedicated to the memory of Leonid Volevich 相似文献
13.
Alp Arslan Kiraç 《Letters in Mathematical Physics》2008,83(2):149-161
Consider the Mathieu–Hill operator
in , where . We obtain the precise asymptotic formulas for the widths γ
k
of the instability intervals of L. The formula states the isolated terms of arbitrary number in the asymptotics of the sequence γ
k
for large k and verifies the results of Harrell (Am J Math suppl:139–150, 1981) and Avron and Simon (Ann Phys 134:76–84, 1981).
相似文献
14.
Christof Puhle 《Communications in Mathematical Physics》2009,291(2):303-320
Any Spin (7)-manifold admits a metric connection ∇
c
with totally skew- symmetric torsion T
c
preserving the underlying structure. We classify those with ∇
c
-parallel T
c
≠ 0 and non-Abelian isotropy algebra . These are isometric to either Riemannian products or homogeneous naturally reductive spaces, each admitting two ∇
c
-parallel spinor fields.
Supported by the SFB 647: ‘Space–Time–Matter’, German Research Foundation DFG. 相似文献
15.
For a quantum system ofn identical spins of magnitudej, we introduce an integrated density of states of definite total spin angular momentum. The underlying sequence
of probability measures satisfies Varadhan's large deviation principle, and converges to a degenerate distribution. We use the Berezin-Lieb Inequalities to obtain upper and lower bounds for the limiting specific free-energy of the spins interacting with a second quantum system under specified conditions on the Hamiltonian. The method is illustrated by applications to the BCS model and to the Dicke maser model. 相似文献
16.
Justin Kinney Juan Maldacena Shiraz Minwalla Suvrat Raju 《Communications in Mathematical Physics》2007,275(1):209-254
We present a trace formula for an index over the spectrum of four dimensional superconformal field theories on S
3 × time. Our index receives contributions from states invariant under at least one supercharge and captures all information
– that may be obtained purely from group theory – about protected short representations in 4 dimensional superconformal field
theories. In the case of the theory our index is a function of four continuous variables. We compute it at weak coupling using gauge theory and at strong
coupling by summing over the spectrum of free massless particles in AdS
5 × S
5 and find perfect agreement at large N and small charges. Our index does not reproduce the entropy of supersymmetric black holes in AdS
5, but this is not a contradiction, as it differs qualitatively from the partition function over supersymmetric states of the
theory. We note that entropy for some small supersymmetric AdS
5 black holes may be reproduced via a D-brane counting involving giant gravitons. For big black holes we find a qualitative
(but not exact) agreement with the naive counting of BPS states in the free Yang Mills theory. In this paper we also evaluate
and study the partition function over the chiral ring in the Yang Mills theory. 相似文献
17.
Indranil Biswas Tomás L. Gómez Norbert Hoffmann Marina Logares 《Communications in Mathematical Physics》2009,290(1):357-369
Fix integers g ≥ 3 and r ≥ 2, with r ≥ 3 if g = 3. Given a compact connected Riemann surface X of genus g, let denote the corresponding Deligne–Hitchin moduli space. We prove that the complex analytic space determines (up to an isomorphism) the unordered pair , where is the Riemann surface defined by the opposite almost complex structure on X. 相似文献
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K. Kumagai K. Kakuyanagi M. Saitoh Y. Matsuda M. Hasegawa S. Takashima M. Nohara H. Takagi 《Hyperfine Interactions》2004,159(1-4):87-93
Spatially-resolved NMR is used to probe internal structures in highly correlated superconductors of optimally-doped (T
c
= 85 K) and a heavy fermion superconductor CeCoIn5 (T
c
= 2.3 K). The characteristic change of the properties of 205Tl-NMR in the vortex state provides a clear evidence of the antiferromagnetic order in the vortex cores below 20 K in . We also obtain anomalous 115In-NMR spectra of CeCoIn5, which provides a microscopic evidence for the occurrence of a spatially-modulated superconducting order parameter expected
in a Fulde–Ferrel–Larkin–Ovchinnkov (FFLO) state. 相似文献
20.
For a quasi-Fuchsian group Γ with ordinary set Ω, and Δ
n
the Laplacian on n-differentials on Γ\Ω, we define a notion of a Bers dual basis for ker Δ
n
. We prove that det , is, up to an anomaly computed by Takhtajan and the second author in (Commun. Math Phys 239(1-2):183–240, 2003), the modulus
squared of a holomorphic function F(n), where F(n) is a quasi-Fuchsian analogue of the Selberg zeta function Z(n). This generalizes the D’Hoker–Phong formula det , and is a quasi-Fuchsian counterpart of the result for Schottky groups proved by Takhtajan and the first author in Analysis
16, 1291–1323, 2006.
相似文献