11292038
Nonsymmetric gravitation theories and local Lorentz invariance.
We analyze the motion and internal structure of test bodies in theories of gravity which couple the antisymmetric part of a nonsymmetric-tensor gravitational field to the electromagnetic field. We establish that such theories necessarily violate the Einstein equivalence principle by breaking local Lorentz invariance. We also show how atomic-physics experiments designed to test the isotropy of space can be used to test these nonsymmetric theories of gravity. We comment briefly on the constraint such experiments are capable of imposing on Moffat's nonsymmetric gravitation theory, the prototype for the theories of gravity we study
119405301
Infinite Blueshift of Charged Null Particles
We demonstrate that charged null particles can be infinitely blue\-shifted in a Kerr-Newman spacetime. The surface of infinite blueshift can be outside of the ergosphere in a Kerr-Newman spacetime, and outside of the outer event horizon for a Reissner-Nordstrom spacetime. Implications for extensions of the standard model which incorporate charged neutrinos are discussed.
119063280
Quasilocal energy and naked black holes
We extend the Brown and York notion of quasilocal energy to include coupled electromagnetic and dilaton fields and also allow for spatial boundaries that are not orthogonal to the foliation of the spacetime. We investigate how the quasilocal quantities measured by sets of observers transform with respect to boosts. As a natural application of this work we investigate the naked black holes of Horowitz and Ross calculating the quasilocal energies measured by static versus infalling observers.
461049
Testing the Equivalence Principle in the Quantum Regime
We consider possible tests of the Einstein Equivalence Principle for physical systems in which quantum-mechanical vacuum energies cannot be neglected. Specific tests include a search for the manifestation of non-metric effects in Lamb-shift transitions of hydrogenic atoms and in anomalous magnetic moments of massive leptons. We discuss how current experiments already set bounds on the violation of the equivalence principle in this sector and how new (high-precision) measurements of these quantities could provide further information to this end.
122503780
PERTURBED W3 CONFORMAL THEORIES AND SPIN-4/3 PARAFERMIONIC COSET MODELS
Renormalization group flows in W3, conformal theories are analyzed in relation to the ones in spin-4/3 parafermionic coset models and some of the operator content for new fixed points is identified.
120488665
Lowest dimensional gravity
36786038
Neutrino oscillations and the solar-neutrino problem.
The values of neutrino masses and mixing angles which are required by the Mikheyev-Smirnov-Wolfenstein (MSW) solution to the solar-neutrino problem are found from analytic solutions to the neutrino propagation equations in the Sun. They coincide with those obtained through extensive numerical computations by Rosen and Gelb. They divide into three classes of oscillation parameters that can solve the solar-neutrino problem. The gallium solar-neutrino experiment will be able to test only two alternatives. However, the third alternative yields sizable oscillations of atmospheric neutrinos in Earth which can be detected by the massive deep-underground proton-decay detectors and neutrino telescopes. Finally, some solutions yield a sizable amplification of neutrino oscillations in Earth which change both the flavor and the spectrum of solar neutrinos that reach terrestrial detectors at night. The day-night modulation of the flux of solar neutrinos perhaps can be used to establish their solar origin in the radiochemical detectors and the MSW solution to the solar-neutrino problem.