118906232
Hydrodynamic fluctuations, long-time tails, and supersymmetry
Hydrodynamic fluctuations at non-zero temperature can cause slow relaxation toward equilibrium even in observables which are not locally conserved. A classic example is the stress-stress correlator in a normal fluid, which, at zero wavenumber, behaves at large times as t^{-3/2}. A novel feature of the effective theory of hydrodynamic fluctuations in supersymmetric theories is the presence of Grassmann-valued classical fields describing macroscopic supercharge density fluctuations. We show that hydrodynamic fluctuations in supersymmetric theories generate essentially the same long-time power-law tails in real-time correlation functions that are known in simple fluids. In particular, a t^{-3/2} long-time tail must exist in the stress-stress correlator of N=4 supersymmetric Yang-Mills theory at non-zero temperature, regardless of the value of the coupling. Consequently, this feature of finite-temperature dynamics can provide an interesting test of the AdS/CFT correspondence. However, the coefficient of this long-time tail is suppressed by a factor of 1/N_c^2. On the gravitational side, this implies that these long-time tails are not present in the classical supergravity limit; they must instead be produced by one-loop gravitational fluctuations.
125172147
THE INSTABILITY OF HOT FLAT SPACE
17198705
Necessary and sufficient conditions for non-perturbative equivalences of large Nc orbifold gauge theories
Large N coherent state methods are used to study the relation between U(Nc) gauge theories containing adjoint representation matter fields and their orbifold projections. The classical dynamical systems which reproduce the large Nc limits of the quantum dynamics in parent and daughter orbifold theories are compared. We demonstrate that the large Nc dynamics of the parent theory, restricted to the subspace invariant under the orbifold projection symmetry, and the large Nc dynamics of the daughter theory, restricted to the untwisted sector invariant under ``theory space'' permutations, coincide. This implies equality, in the large Nc limit, between appropriately identified connected correlation functions in parent and daughter theories, provided the orbifold projection symmetry is not spontaneously broken in the parent theory and the theory space permutation symmetry is not spontaneously broken in the daughter. The necessity of these symmetry realization conditions for the validity of the large Nc equivalence is unsurprising, but demonstrating the sufficiency of these conditions is new. This work extends an earlier proof of non-perturbative large Nc equivalence which was only valid in the phase of the (lattice regularized) theories continuously connected to large mass and strong coupling [1].
122912012
Canonical treatment of «noncanonical» gauges for constrained Hamiltonian systems
15540326
Higher-order instanton effects
We present a formalism for calculating higher-order instanton effects based on a systematic expansion of the functional integrals about multiple instanton-anti-instanton configurations. We consider how various correlation functions may be constructed from the determinants and propagators in a background multiple-instanton field. A multiple-scattering formalism is then developed in order to express these determinants and propagators for a multi-instanton field in terms of the basic single-instanton quantities. The introduction of an improved gluon propagator based on a different choice of zero-mode constraints is required in order to justify the multiple-scattering formalism. As examples of this approach, we consider instanton interactions, which appear as corrections to the dilute-gas approximation for the instanton density, and the first-order quantum contributions to the static quark potential.
118596387
Holographic realization of large-Nc orbifold equivalence with non-zero chemical potential
A bstractRecently, it has been suggested that large-Nc orbifold equivalences may be applicable to certain theories with chemical potentials, including QCD, in certain portions of their phase diagram. When valid, such an equivalence offers the possibility of relating large-Nc QCD at non-zero baryon chemical potential, a theory with a complex fermion determinant, to a related theory whose fermion determinant is real and positive. In this paper, we provide a test of this large Nc equivalence using a holographic realization of a supersymmetric theory with baryon chemical potential and a related theory with isospin chemical potential. We show that the two strongly-coupled, large-Nc theories are equivalent in a large region of the phase diagram.
122070464
Preparation of thin Films, Sources, and Targets
and targets are an obvious need in many applic a­ tions in nuclear physics and nuclear chemistry experiments. Publis hed in­ formation regarding the production and measurement of these materials is exceedingly sparse. The information. if given at all in the li terature, is usuaIJy ancillary to the "re sult s," and thus is given in such meager form that duplic a­ tion by other laboratories is difficult, if not well-nigh impossible. The most recent comprehensive article on the subject is that pub lished by Dodson et at. in the National Nuclear Energy Series, 1952, entitled Miscellaneous Physical and Chemical Techniques of the Los Alamos Series [referred to later as (58 )]. 2 Often the information exists as the "propert y" of a few exceedingly valuable individuals in various labor atories who prepare the materials but never publis h. The situat ion has impr oved somewhat since the appe arance of two journals devoted exclus ively to techniques, viz. Nuclear Instruments and Methods (North-Holland Publi shing Co.) and the Rus sian journal Pribory i Technika Eksperimenta (Instru ments and Experimental Tech­ niques) . The aim of this review article is to collate as much of this information as is possible. In this task the reviewer has been aided by peo ple too numerous to mention, and it is hoped that this assistance is reflected in the references. In addition, a literature search has been made, which, no matter how exhaus­ tively undertaken, must by its very nature be incomplete. It is hoped that this article will stimulate others int o rectifying these om issions by sending references and unpu blished information to the author for later publication.
120217954
( p , xn ) and ( p , pxn ) Reactions of Yttrium-89 with 5-85-MeV Protons