A Spectral Study of the Linearized Boltzmann Equation for Diffusively Excited Granular Media

In this work, we are interested in the spectrum of the diffusively excited granular gases equation, in a space inhomogeneous setting, linearized around an homogeneous equilibrium. We perform a study which generalizes to a non-hilbertian setting and to the inelastic case the seminal work of Ellis and Pinsky about the spectrum of the linearized Boltzmann operator. We first give a precise localization of the spectrum, which consists in an essential part lying on the left of the imaginary axis and a discrete spectrum, which is also of nonnegative real part for small values of the inelasticity parameter. We then give the so-called inelastic "dispersion relations", and compute an expansion of the branches of eigenvalues of the linear operator, for small Fourier (in space) frequencies and small inelasticity. One of the main novelty in this work, apart from the study of the inelastic case, is that we consider an exponentially weighted $L^1(m^{-1})$ Banach setting instead of the classical $L^2(\mathcal M_{1,0,1}^{-1})$ Hilbertian case, endorsed with Gaussian weights. We prove in particular that the results of Ellis and Pinsky holds also in this space.Comment: 30 pages, 2 figure

SYM Correlators and the Maldacena Conjecture

We report on progress in evaluating quantum filed theories with supersymmetric discrete light-cone quantization (SDLCQ). We compare the method to lattice gauge theory and point out its relevance for lattice calculations. As an exciting application we present a test of the Maldacena conjecture. We test the conjecture by evaluating the correlator of the stress-energy tensor in the strong coupling field theory and comparing to the string theory prediction of its behavior as a function of the distance. Our numerical results support the Maldacena conjecture and are within 10-15% of the predicted results.Comment: 3 pages, 1 figure, talk at Lattice2002(higgssusy), to appear in the proceeding

Interview with Robert Pinsky

Robert Pinsky has published nineteen volumes of poetry and prose, including a translation of Dante\u27s Inferno, He served as U. S. Poet Laureate from 1997-2000, has won countless awards, and has been nominated for both the Pulitzer Prize and the National Book Critics Circle Award. He\u27s taught on both coasts and in Chicago, and was called the last of the \u27civic\u27 or public poets by the Poetry Foundation. His work has the meticulous, meditative beauty of a Japanese garden and the deliberate wit of an American East-coast native. As Poet Laureate, Pinsky started the Favorite Poem Project, a public-outreach effort that convinced 18,000 Americans to share their favorite poem during a one-year open call for submissions in the late 1990s. That project now sponsors an annual week-long summer institute for teachers, with a focus on poetry as an out-loud art form. He believes this continuing effort to keep poetry in the American consciousness is far more important than the title he held as Poet Laureate

Anomalously light mesons in a (1+1)-dimensional supersymmetric theory with fundamental matter

We consider N=1 supersymmetric Yang-Mills theory with fundamental matter in the large-N_c approximation in 1+1 dimensions. We add a Chern-Simons term to give the adjoint partons a mass and solve for the meson bound states. Here mesons are color-singlet states with two partons in the fundamental representation but are not necessarily bosons. We find that this theory has anomalously light meson bound states at intermediate and strong coupling. We also examine the structure functions for these states and find that they prefer to have as many partons as possible at low longitudinal momentum fraction.Comment: 14 pages, 3 figures, LaTe

Nonperturbative solution of supersymmetric gauge theories

Recent work on the numerical solution of supersymmetric gauge theories is described. The method used is SDLCQ (supersymmetric discrete light-cone quantization). An application to N=1 supersymmetric Yang-Mills theory in 2+1 dimensions at large N_c is summarized. The addition of a Chern-Simons term is also discussed.Comment: 9 pages, LaTeX2e, ws-procs9x6; to appear in the proceedings of the fifth workshop on Continuous Advances in QCD (Arkadyfest), Minneapolis, Minnesota, May 17-23, 200

Numerical Simulations of N=(1,1) SYM{1+1} with Large Supersymmetry Breaking

We consider the $N=(1,1)$ SYM theory that is obtained by dimensionally reducing SYM theory in 2+1 dimensions to 1+1 dimensions and discuss soft supersymmetry breaking. We discuss the numerical simulation of this theory using SDLCQ when either the boson or the fermion has a large mass. We compare our result to the pure adjoint fermion theory and pure adjoint boson DLCQ calculations of Klebanov, Demeterfi, and Bhanot and of Kutasov. With a large boson mass we find that it is necessary to add additional operators to the theory to obtain sensible results. When a large fermion mass is added to the theory we find that it is not necessary to add operators to obtain a sensible theory. The theory of the adjoint boson is a theory that has stringy bound states similar to the full SYM theory. We also discuss another theory of adjoint bosons with a spectrum similar to that obtained by Klebanov, Demeterfi, and Bhanot.Comment: 12 pages, 4 figure