GENERAL RELATIVISTIC EFFECTS ON THE INDUCED ELECTRIC FIELD EXTERIOR TO PULSARS

The importance of general relativity to the induced electric field exterior to pulsars has been investigated by assuming aligned vacuum and non-vacuum magnetosphere models. For this purpose the stationary and axisymmetric vector potential in Schwarzschild geometry has been considered and the corresponding expressions for the induced electric field due to the rotation of the magnetic dipole have been derived for both vacuum and non-vacuum conditions. Due to the change in the magnetic dipole field in curved spacetime the induced electric field also changes its magnitude and direction and increases significantly near the surface of the star. As a consequence the surface charge density, the acceleration of charged particles in vacuum magnetospheres and the space charge density in non-vacuum magnetosphere greatly increase near the surface of the star. The results provide the most general feature of the important role played by gravitation and could have several potentially important implications for the production of high-energy radiation from pulsars.Comment: 16 pages, LATEX, 7 figures available upon request, to appear in The Astrophysical Journa

Modulus stabilization of generalized Randall Sundrum model with bulk scalar field

We study the stabilization of inter-brane spacing modulus of generalized warped brane models with a nonzero brane cosmological constant. Employing Goldberger-Wise stabilization prescription of brane world models with a bulk scalar field, we show that the stabilized value of the modulus generally depends on the value of the brane cosmological constant. Our result further reveals that the stabilized modulus value corresponding to a vanishingly small cosmological constant can only resolve the gauge hierarchy problem simultaneously. This in turn vindicates the original Randall-Sundrum model where the 3-brane cosmological constant was chosen to be zero.Comment: 12 Pages, 1 figure, Revtex, Version to appear in Euro. Phys. Let

Three dimensional thermal pollution models. Volume 1: Review of mathematical formulations

A mathematical model package for thermal pollution analyses and prediction is presented. These models, intended as user's manuals, are three dimensional and time dependent using the primitive equation approach. Although they have sufficient generality for application at sites with diverse topographical features; they also present specific instructions regarding data preparation for program execution and sample problems. The mathematical formulation of these models is presented including assumptions, approximations, governing equations, boundary and initial conditions, numerical method of solution, and same results

Three dimensional thermal pollution models. Volume 3: Free surface models

Two sets of programs, named Nasum 2 and Nasum 3 are presented in detail. Nasum 2 is a far field formulation and is used without including the plant thermal discharge. Nasum 3 uses horizontal stretching to provide higher resolution at thermal discharge joints; and includes far field influences such as varying tides and ambient currents far from point of discharge

Thermal Pollution Math Model. Volume 1. Thermal Pollution Model Package Verification and Transfer

Two three dimensional, time dependent models, one free surface, the other rigid lid, were verified at Anclote Anchorage and Lake Keowee respectively. The first site is a coastal site in northern Florida; the other is a man-made lake in South Carolina. These models describe the dispersion of heated discharges from power plants under the action of ambient conditions. A one dimensional, horizontally-averaged model was also developed and verified at Lake Keowee. The data base consisted of archival in situ measurements and data collected during field missions. The field missions were conducted during winter and summer conditions at each site. Each mission consisted of four infrared scanner flights with supporting ground truth and in situ measurements. At Anclote, special care was taken to characterize the complete tidal cycle. The three dimensional model results compared with IR data for thermal plumes on an average within 1 C root mean square difference. The one dimensional model performed satisfactorily in simulating the 1971-1979 period

Renormalization group approach to spinor Bose-Fermi mixtures in a shallow optical lattice

We study a mixture of ultracold spin-half fermionic and spin-one bosonic atoms in a shallow optical lattice where the bosons are coupled to the fermions via both density-density and spin-spin interactions. We consider the parameter regime where the bosons are in a superfluid ground state, integrate them out, and obtain an effective action for the fermions. We carry out a renormalization group analysis of this effective fermionic action at low temperatures, show that the presence of the spinor bosons may lead to a separation of Fermi surfaces of the spin-up and spin-down fermions, and investigate the parameter range where this phenomenon occurs. We also calculate the susceptibilities corresponding to the possible superfluid instabilities of the fermions and obtain their possible broken-symmetry ground states at low temperatures and weak interactions.Comment: 8 pages, 8 figs v