34781515
Magnetic wormholes and vertex operators.
We consider wormhole solutions in 2+1 Euclidean dimensions. A duality transformation is introduced to derive a new action from the magnetic wormhole action of Gupta, Hughes, Preskill, and Wise. The classical solution is presented. The vertex operators corresponding to the wormhole are derived. Conformally coupled scalars and spinors are considered in the wormhole background and the vertex operators are computed.
99770174
Supersymmetric Configurations in Gauged Supergravity
We discuss supersymmetric configurations in gauged supergravity theories with particular emphasis on Euclidean D = 4, N = 4 gauged SU(2) × SU(1,1) supergravity.
119502296
MACROSCOPIC STRING-LIKE SOLUTIONS IN MASSIVE SUPERGRAVITY
In this report we obtain explicit string-like solutions of equations of motion of massive heterotic supergravity recently obtained by Bergshoeff, Roo and Eyras. We also find consistent string source which can be embedded in these backgrounds when space-time dimension is greater than or equal to six.
6879560
On the compactification of type IIA string theory
The ten dimensional type IIA string effective action with cosmological constant term is dimensionally reduced on a d-dimensional torus to derive lower dimensional effective action. The symmetries of the reduced effective action are examined. It is shown that the resulting six dimensional theory does not remain invariant under SO(4,4) symmetry whereas the reduced action, in the absence of the cosmological constant respects the symmetry as was shown by Sen and Vafa. New class of black hole solutions are obtained in five and four dimensions in the presence of cosmological constant. For the six dimensional theory, a four brane solution is presented.
15672232
S duality and cosmological constant in string theory
Abstract The S -duality invariance of the equations of motion of four dimensional string effective action with cosmological constant, Λ, is studied. It is demonstrated that the S -duality symmetry of the field equations are broken for nonzero Λ. The “naturalness” hypothesis is invoked to argue that Λ should remain small since exact S -duality symmetry will force the cosmological constant to vanish in the string effective action.
5287390
Galilean anti-de-Sitter spacetime in Romans theory
Abstract The Romans type IIA theory is the only known example of 10-dimensional maximal supergravity where (tensor) fields are explicitly massive. We provide an example of a non-relativistic anti-de-Sitter NRadS 4 × S 6 background as a solution in massive type IIA. A compactification of which on S 6 gives immediately the prototype NRadS background in D = 4 which is proposed to be dual to ‘cold atoms’ or unitary fermions on a wire.
29912513
Quantum gravitational corrections to the functional Schrödinger equation.
We derive corrections to the Schr\"odinger equation which arise from the quantization of the gravitational field. This is achieved through an expansion of the full functional Wheeler-DeWitt equation with respect to powers of the gravitational constant. The correction terms fall into two classes: One describes the breakdown of the classical background picture while the other corresponds to quantum gravitational corrections for the matter fields themselves. The latter are independent of the factor ordering which is chosen for the gravitational kinetic term. If the total state evolves adiabatically, the only correction term that survives contains the square of the matter Hamiltonian. In the general case there are also smaller terms which describe a gravitationally induced violation of unitarity. The corrections are numerically extremely tiny except near the big bang and the final stages of a black hole. They are also of principle significance for quantum field theories near the Planck scale.
37575993
Coulomb excitation studies in antimony isotopes.
Various low-lying energy levels up to 1.145 MeV in {sup 121,123}Sb have been Coulomb excited using 3.0--4.0 MeV proton-beam energies. The reduced transition probabilities of the excited levels have been newly deduced from the measured yields of the deexcitation gamma rays. The values of mixing ratios for a few transitions and the removal of ambiguities in the spin values of some levels have been presented from the angular distribution analysis.
36641344
On the relation between causality and topology in the semiclassical universe.
11413480
Interacting quasiopen strings.
A 26-dimensional quasiopen string, in which Poincare invariance in some dimensions is broken by new boundary conditions, has also a new mass spectrum. Based on locality we construct vertex operators and generalized dual Veneziano amplitudes with singularities corresponding to the quasiopen mass spectrum.
28689431
Quantization of Nambu-Goto strings with new boundary conditions.
If a classical Nambu-Goto string in D dimensions is required to have Poincare invariance in d dimensions, d