A 2D Inspired 4D Theory of Gravity

Coadjoint orbits of the Virasoro and Kac-Moody algebras provide geometric actions for matter coupled to gravity and gauge fields in two dimensions. However, the Gauss' law constraints that arise from these actions are not necessarily endemic to two-dimensional topologies. Indeed the constraints associated with Yang-Mills naturally arise from the coadjoint orbit construction of the WZW model. One may in fact use a Yang-Mills theory to provide dynamics to the otherwise fixed coadjoint vectors that define the orbits. In this letter we would like to exhibit an analogue of the Yang-Mills classical action for the diffeomorphism sector. With this analogue one may postulate a 4D theory of gravitation that is related to an underlying two dimensional theory. Instead of quadratic differentials, a (1,3) pseudo tensor becomes the dynamical variable. We briefly discuss how this tensor may be classically coupled to matter.Comment: 8 pages, UI-94-11 (minor typos corrected in eq 11 and eq 2

Supergravity solutions with AdS(4) from non-Abelian T-dualities

We present a large class of new backgrounds that are solutions of type II supergravity with a warped AdS(4) factor, non-trivial axion-dilaton, B-field, and three-and five-form Ramond-Ramond fluxes. We obtain these solutions by applying non-Abelian T-dualities with respect to SU(2) or SU(2)/U(1) isometries to reductions to 10d IIA of 11d sugra solutions of the form AdS(4) x Y-7, with Y-7 = S-7/Z(k), S-7, M-1,M-1,M-1, Q(1,1,1) and N(1,1). The main class of reductions to IIA is along the Hopf fiber and leads to solutions of the form AdS(4) x K-6, where K-6 is Kahler Einstein with K-6 = CP3, S-2 x CP2, S-2 x S-2 x S-2; the first member of this class is dual to the ABJM field theory in the 't Hooft limit. We also consider other less symmetric but susy preserving reductions along circles that are not the Hopf fiber. In the case of N(1,1) we find an additional breaking of isometries in the NAT-dual background. To initiate the study of some properties of the field theory dual, we explicitly compute the central charge holographically.SP1

Yang-Mills, Gravity, and String Symmetries

In this work we use constructs from the dual space of the semi-direct product of the Virasoro algebra and the affine Lie algebra of a circle to write a theory of gravitation which is a natural analogue of Yang-Mills theory. The theory provides a relation between quadratic differentials in 1+1 dimensions and rank two symmetric tensors in higher dimensions as well as a covariant local Lagrangian for two dimensional gravity. The isotropy equations of coadjoint orbits are interpreted as Gauss law constraints for a field theory in two dimensions, which enables us to extend to higher dimensions. The theory has a Newtonian limit in any space-time dimension. Our approach introduces a novel relationship between string theories and 2D field theories that might be useful in defining dual theories. We briefly discuss how this gravitational field couples to fermions.Comment: To Appear in Phys. Lett. B, In memory of Emma Meuric

Irreducible Decomposition of Products of 10D Chiral Sigma Matrices

We review the enveloping algebra of the 10 dimensional chiral sigma matrices. To facilitate the computation of the product of several chiral sigma matrices we have developed a symbolic program. Using this program one can reduce the multiplication of the sigma matrices down to linear combinations of irreducilbe elements. We are able to quickly derive several identities that are not restricted to traces. A copy of the program written in the Mathematica language is provided for the community.Comment: 28 pages, Mathematica Program sigmavector10D.nb is included. Submitted ot CP

The Image of Self Intersecting QCD Strings in Four Dimensions

We numerically examine the self-dual solutions of self-intersecting strings immersed in four dimensions. We find that open torus knots have topologies that can support monopole/anti-monopole as well as q-qbar production and annihilation. We give an estimate of the string tension from quark production rates, show that the intersection number for torus-knots is 4(p-q), and discuss a chiral symmetry breaking mechanism due to self-intersections. We supply a MAPLE program that can annimate the torus-knot solutions. These annimations can be found at http://www-hep.physics.uiowa.edu/~bacus/research.html under the ``Animation Control Panel''.Comment: 15 pages Latex, 39 figures, corrected typos and spellin

A Truly Crazy Idea About Type-IIB Supergravity and Heterotic Sigma-Models

We construct an explicit and manifestly (1,0) heterotic sigma-model where the background fields are those of 10D, N=IIB supergravity.Comment: 10 Pages, Latex (self contained macros

A Study of Fermions Coupled to Gauge and Gravitational Fields on a Cylinder

Fermions on a cylinder coupled to gravity and gauge fields are examined by studying the geometric action associated with the symmetries of such a system. The gauge coupling constant is shown to be constrained and the effect of gravity on the masses is discussed. Furthermore, we introduce a new gravitational theory which couples to the fermions by promoting the coadjoint vector of the diffeomorphism sector to a dynamical variable. This system, together with the gauge sector is shown to be equivalent to a one dimensional system.Comment: 16 pages, UI-94-2 (Some minor typographical errors are cleaned up.

Chiral Supergravitons Interacting with a 0-Brane N-Extended NSR Super-Virasoro Group

We continue the development of the actions, S_{AFF}, by examining the cases where there are N fermionic degrees of freedom associated with a 0-brane. These actions correspond to the interaction of the N-extended super Virasoro algebra with the supergraviton and the associated SO(N) gauge field that accompanies the supermultiplet. The superfield formalism is used throughout so that supersymmetry is explicit.Comment: PACS: 04.65.+e, 11.15.-q, 11.25.-w, 12.60.

Classical Open String Models in 4-Dim Minkowski Spacetime

Classical bosonic open string models in fourdimensional Minkowski spacetime are discussed. A special attention is paid to the choice of edge conditions, which can follow consistently from the action principle. We consider lagrangians that can depend on second order derivatives of worldsheet coordinates. A revised interpretation of the variational problem for such theories is given. We derive a general form of a boundary term that can be added to the open string action to control edge conditions and modify conservation laws. An extended boundary problem for minimal surfaces is examined. Following the treatment of this model in the geometric approach, we obtain that classical open string states correspond to solutions of a complex Liouville equation. In contrast to the Nambu-Goto case, the Liouville potential is finite and constant at worldsheet boundaries. The phase part of the potential defines topological sectors of solutions.Comment: 25 pages, LaTeX, preprint TPJU-28-93 (the previous version was truncated by ftp...