16976530
Quasilocal thermodynamics of dilaton gravity coupled to gauge fields.
We consider an Einstein-Hilbert-dilaton action for gravity coupled to various types of Abelian and non-Abelian gauge fields in a spatially finite system. These include Yang-Mills fields and Abelian gauge fields with three-form and four-form field strengths. We obtain various quasilocal quantities associated with these fields, including their energy and angular momentum, and develop methods for calculating conserved charges when a solution possesses sufficient symmetry. For stationary black holes, we find an expression for the entropy from the microcanonical form of the action. We also find a form of the first law of black hole thermodynamics for black holes with the gauge fields of the type considered here.
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.
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.
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
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.
687385
Nonclassical interferometry with intelligent light.
We study the phase sensitivity of SU(2) and SU(1,1) interferometers fed by two-mode field states which are intelligent states for Hermitian generators of the SU(2) and SU(1,1) groups, respectively. Intelligent states minimize uncertainty relations and this makes possible an essential reduction of the quantum noise in interferometers. Exact closed expressions for the minimum detectable phase shift are obtained in terms of the Jacobi polynomials. These expressions are compared with results for some conventional input states, and some known results for the squeezed input states are reviewed. It is shown that the phase sensitivity for an interferometer that employs squeezing-producing active devices (such as four-wave mixers) should be analyzed in two regimes: (i) fixed input state and variable interferometer, and (ii) fixed interferometer and variable input state. The behavior of the phase sensitivity is essentially different in these two regimes. The use of the SU(2) intelligent states allows us to achieve a phase sensitivity of order $1/\bar{N}$ (where $\bar{N}$ is the total number of photons passing through the phase shifters of the interferometer) without adding four-wave mixers. This avoids the duality in the behavior of the phase sensitivity that occurs for the squeezed input. On the other hand, the SU(1,1) intelligent states have the property of achieving the phase sensitivity of order $1/\bar{N}$ in both regimes.
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.