802 publications from this institution
We develop techniques to compute the complete massless spectrum in heterotic string compactification on N = 2 supersymmetric Landau-Ginzburg orbifolds. This includes not just the familiar charged fields, but also the gauge singlets. The number of gauge singlets can vary in the moduli space of a given compactification and can differ from what it would be in the large radius limit of the corresponding Calabi-Yau. Comparison with exactly soluble Gepner models provides a confirmation of our results at Gepner points. Our methods carry over straightforwardly to (0, 2) Landau-Ginzburg models.
International Press of Boston - publishers of scholarly mathematical and scientific journals and books
Making use of known facts about tensor models, it is possible to construct a quantum system without quenched disorder that has the same large $n$ limit for its correlation functions and thermodynamics as the SYK model. This might be useful in further probes of this approach to holographic duality.
We prove that for genus greater than or equal to 5, the moduli space of super Riemann surfaces is not projected (and in particular is not split): it cannot be holomorphically projected to its underlying reduced manifold. Physically, this means that certain approaches to superstring perturbation theory that are very powerful in low orders have no close analog in higher orders. Mathematically, it means that the moduli space of super Riemann surfaces cannot be constructed in an elementary way starting with the moduli space of ordinary Riemann surfaces. It has a life of its own.
Chromodynamics with n flavors of massless quarks is invariant under chiral U(n) × U(n). We show that in the limit of large number of colors, under reasonable assumptions, this symmetry group must spontaneously break down to diagonal U(n).
Perturbative superstring theory is revisited, with the goal of giving a simpler and more direct demonstration that multi-loop amplitudes are gauge-invariant (apart from known anomalies), satisfy space-time supersymmetry when expected, and have the ex- pected infrared behavior. The main technical tool is to make the whole analysis, including especially those arguments that involve integration by parts, on supermoduli space, rather than after descending to ordinary moduli space.
We show that the nonlinear sigma model can be coupled to supergravity only if Newton's constant is an integral multiple of 1/F π 2.
A supersymmetric form of the two-dimensional nonlinear $\ensuremath{\sigma}$ model is described; the primary purpose is to explore further the analogy between the $\ensuremath{\sigma}$ model and four-dimensional Yang-Mills theory. In the case of three components, the theory contains an enlarged supersymmetry algebra and is equivalent to the ordinary $\ensuremath{\sigma}$ model with an additional logarithmic interaction between pseudoparticles.
The review of the problems of neutrino detection and mass measurement is given. The astrophysical consequences of a nonzero neutrino mass are considered along with recent developments on neutrino oscillations. (AIP)
We reconsider Chern-Simons gauge theory on a Seifert manifold M (the total space of a nontrivial circle bundle over a Riemann surface). When M is a Seifert manifold, Lawrence and Rozansky have shown from the exact solution of Chern-Simons theory that the partition function has a remarkably simple structure and can be rewritten entirely as a sum of local contributions from the flat connections on M. We explain how this empirical fact follows from the technique of non-abelian localization as applied to the Chern-Simons path integral. In the process, we show that the partition function of Chern-Simons theory on M admits a topological interpretation in terms of the equivariant cohomology of the moduli space of flat connections on M.
We show that the two-dimensional (ψψ)2 model is, for N = 3, equivalent to the supersymmetric sine-Gordon equation, and for N = 4, equivalent to two decoupled sine-Gordon systems. In addition, we argue that the kinks of this model are isospinors, and we construct some of the higher conservation laws that are responsible for the exact solubility of this system.
The U(1) problem is reconsidered from the point of view of the 1 N expansion. It is argued that various heuristic ideas about the η′ are valid from this point of view. Current algebra theorems, similar to soft π theorems, are derived for the η′. They are valid to lowest order in 1 N .
No abstract is provided for this article.
This paper summarizes our rather lengthy paper, "Algebra of the Infrared: String Field Theoretic Structures in Massive ${\cal N}=(2,2)$ Field Theory In Two Dimensions," and is meant to be an informal, yet detailed, introduction and summary of that larger work.
We show that in all theories with a Lorentz-covariant energy-momentum tensor, such as all known renormalizable quantum field theories, composite as well as elementary massless particles with j > 1 are forbidden. Also, in all theories with a Lorentz-covariant conserved current, such as renormalizable theories with a symmetry that commutes with all local symmetries, there cannot exist composite or elementary particles with nonvanishing values of the corresponding charge and j > 1/2.
