Quenched master field equations for unitary matrix models

We derive the quenched master field equations for constrained systems such as the O(N) non-linear sigma model, U(N)×U(N) chiral models, and U(N) lattice gauge theory. The master equations are algebraic, and involve quenching in both the space and “fifth” (Langevin) time directions. The quenched master field for the O(N) nonlinear sigma model is found exactly. The 0-dimensional unitary matrix model is solved perturbatively, and we recover the Gross-Witten result. The master equation for the U(N)×U(N) chiral model is set up for non-perturbative approximation methods, and some qualitative results are obtained.     

Detection of master fields near factorization

In reduced models we verify numerically the onset of factorization (N^?1 fluctuations), and the forming up of master fields in that regime.     

Stochastically Stable Quenched Measures

We analyze a class of stochastically stable quenched measures.We prove that stochastic stability is fully characterized by an infinite family of zero average polynomials in the covariance matrix entries.     

Quenched light hadron spectrum

We present results of a large-scale simulation for the flavor nonsinglet light hadron spectrum in quenched lattice QCD with the Wilson quark action. Hadron masses are calculated at four values of lattice spacing in the range a approximately 0.1-0.05 fm on lattices with a physical extent of 3 fm at five quark masses corresponding to m(pi)/m(rho) approximately 0.75-0.4. The calculated spectrum in the continuum limit shows a systematic deviation from experiment, though the magnitude of deviation is contained within 11%. Results for decay constants and light quark masses are also reported.     

Quenched Kosterlitz-Thouless superfluid transitions

Rapidly quenched Kosterlitz-Thouless (KT) superfluid transitions are studied by solving the Fokker-Planck equation for the vortex-pair dynamics in conjunction with the KT recursion relations. Power-law decays of the vortex density at long times are found, and the results are in agreement with a scaling proposal made by Minnhagen and co-workers for the dynamical critical exponent. The superfluid density is strongly depressed after a quench, with the subsequent recovery being logarithmically slow for starting temperatures near T(KT). No evidence is found of vortices being "created" in a rapid quench; there is only decay of the existing thermal vortex pairs.     

Quenched string field theory

We construct a toy model of Witten's open string field theory by truncating the Virasoro group to its SU(1,1) subgroup. The string field is given in terms of finite-dimensional matrices, which satisfy a non-trivial BRST cohomology. The string gauge group is found to be SO(3). Finally, we perform the gauge fixing of the action, finding an explicit formula for calculating the partition function.     

Quenched dislocation enhanced supersolid ordering

I show using Landau theory that quenched dislocations can facilitate the supersolid to normal solid transition, making it possible for the transition to occur even if it does not in a dislocation-free crystal. I make detailed predictions for the dependence of the supersolid to normal solid transition temperature T_{c}(L), superfluid density rho_{S}(T,L), and specific heat C(T,L) on temperature T and dislocation spacing L, all of which can be tested against experiments. The results should also be applicable to an enormous variety of other systems, including, e.g., ferromagnets.     

Quenched noise in surface growth

The analytical continuous equations for the Tang and Leschhorn (Phys. Rev. A 45 (1992) R8309) and the Buldyrev et al. (Phys. Rev. A 45 (1992) R8313) models are derived from the microscopic rules using a regularization procedure. As was shown in a previous paper (Phys. Rev. E 62 (2000) 6970) the continuous equation for the Tang and Leschhorn model is formally different to the Kardar–Parisi–Zhang equation (Phys. Rev. Lett. 56 (1986) 889) with quenched noise (QKPZ). Nevertheless, after expanding the multiplicative noise, it is shown that we recover the usual QKPZ, demonstrating analytically that both equations belong to the same universality class.     

固溶处理态Alnico8合金的微观组织

本文利用透射电镜，X射线衍射及小角散射的分析手段，研究了淬火碥Alnico8合金的微观组织结构。研究结果表明，Alnico8合金在固溶淬火过程中就发生了调幅分解，且冷却速度越快，组织越细小。合金在冷却过程中的调幅分解过程进行的并不充分。合金在固溶淬火过程中发生了两次有序化转变。     

From convolutionless generalized master to finite-coupling Pauli master equations

Time-convolutionless Generalized Master Equations (TCL-GME) for probabilities of finding a system in a general state, irrespective of the state of the thermodynamic bath, are investigated. For general systems interacting with a genuine bath with a continuous spectrum described by time-independent system + bath Hamiltonians and after the thermodynamic limit for the bath, the long-time asymptotics of time-dependent coefficients can be taken as counterparts of Pauli-Master-Equation (PME) transfer rates. Here, within TCL-GME, asymptotics of these coefficients is calculated without resorting to any approximation. In the lowest order, these coefficients are known to turn to the usual Fermi Golden Rule transfer rates. Anyway, we argue that if the exact form of these coefficients has a long-time limit, this limit is inevitably equal to zero. This makes the possibility to derive standard markovian finite-coupling Pauli, rate or balance equations as long-time asymptotics to TCL-GME illusory. Invaluable discussions with Prof. P. Grigolini are also highly appreciated.