Higher spins dynamics in the closed string theory

The general $\sigma$-model-type string action including both massless and massive higher spins background fields is suggested. Field equations for background fields are followed from the requirement of quantum Weyl invariance. It is shown that renormalization of the theory can be produced level by level. The detailed consideration of background fields structure and corresponding fields equations is given for the first massive level of the closed bosonic string.Comment: 11 pages, report TSU/QFTD-36/9

Massive fields dynamics in open bosonic string theory

We consider the theory of open bosonic string in massive background fields. The general structure of renormalization is investigated. A general covariant action for a string in background fields of the first massive level is suggested and its symmetries are described. Equations of motion for the background fields are obtained by demanding that the renormalized operator of the energy-momentum tensor trace vanishes.Comment: 13 page

Generalized canonical quantization of bosonic string model in massive background fields

A method of constructing a canonical gauge invariant quantum formulation for a non-gauge classical theory depending on a set of parameters is advanced and then applied to the theory of closed bosonic string interacting with massive background fields. It is shown that within the proposed formulation the correct linear equations of motion for background fields arise.Comment: 4 pages, LaTeX, talk given by I.L. Buchbinder at the Second Conference on Constrained Dynamics and Quantum Gravity, S. Margherita Ligure, September 17-21 199

A study of semi-inclusive charmless B→πXB \to \pi X decays

We study semi-inclusive charmless decays $B \to \pi X$ in detail, such as $\bar B^0 \to \pi^{\pm (0)} X$, $B^0 \to \pi^{\pm (0)} X$, $B^{\pm} \to \pi^{\pm (0)} X$, where $X$ does not contain a charm (anti)quark. We find that the process $\bar B^0 \to \pi^- X$ ($B^0 \to \pi^+ X$) can be particularly useful for determination of the CKM matrix element $|V_{ub}|$. We calculate and present the branching ratio (BR) of $\bar B^0 \to \pi^- X$ as a function of $|V_{ub}|$, with an estimate of possible uncertainties. It is expected that the BR is an order of $10^{-4}$. Our estimation indicates that one can phenomenologically determine $|V_{ub}|$ with reasonable accuracy by measuring the BR of $\bar B^0 \to \pi^- X$ ($B^0 \to \pi^+ X$).Comment: 18 pages, 7 figures; Revtex; version accepted for publication in Eur. Phys. J.

Determining the Higgs Boson Self Coupling at Hadron Colliders

Inclusive Standard Model Higgs boson pair production at hadron colliders has the capability to determine the Higgs boson self-coupling, lambda. We present a detailed analysis of the gg\to HH\to (W^+W^-)(W^+W^-)\to (jjl^\pm\nu)(jj{l'}^\pm\nu) and gg\to HH\to (W^+W^-)(W^+W^-)\to (jjl^\pm\nu)({l'}^\pm\nu {l''}^\mp\nu) (l, {l'}, {l''}=e, \mu) signal channels, and the relevant background processes, for the CERN Large Hadron Collider, and a future Very Large Hadron Collider operating at a center-of-mass energy of 200 TeV. We also derive quantitative sensitivity limits for lambda. We find that it should be possible at the LHC with design luminosity to establish that the Standard Model Higgs boson has a non-zero self-coupling and that lambda / lambda_{SM} can be restricted to a range of 0-3.8 at 95% confidence level (CL) if its mass is between 150 and 200 GeV. At a 200 TeV collider with an integrated luminosity of 300 fb^{-1}, lambda can be determined with an accuracy of 8 - 25% at 95% CL in the same mass range.Comment: 28 pages, Revtex3, 9 figures, 3 table

Electromagnetic field angular momentum in condensed matter systems

Various electromagnetic systems can carry an angular momentum in their {\bf E} and {\bf B} fields. The electromagnetic field angular momentum (EMAM) of these systems can combine with the spin angular momentum to give composite fermions or composite bosons. In this paper we examine the possiblity that an EMAM could provide an explanation of the fractional quantum Hall effect (FQHE) which is complimentary to the Chern-Simons explanation. We also examine a toy model of a non-BCS superconductor (e.g. high $T_c$ superconductors) in terms of an EMAM. The models presented give a common, simple picture of these two systems in terms of an EMAM. The presence of an EMAM in these systems might be tested through the observation of the decay modes of a charged, spin zero unstable particle inside one of these systems.Comment: 17 pages, no figures, to be published in Phys. Rev.

Lattice QCD Constraints on the Nuclear Equation of State

Based on the quasi-particle description of the QCD medium at finite temperature and density we formulate the phenomenological model for the equation of state that exhibits crossover or the first order deconfinement phase transition. The models are constructed in such a way to be thermodynamically consistent and to satisfy the properties of the ground state nuclear matter comply with constraints from intermediate heavy--ion collision data. Our equations of states show quite reasonable agreement with the recent lattice findings on temperature and baryon chemical potential dependence of relevant thermodynamical quantities in the parameter range covering both the hadronic and quark--gluon sectors. The model predictions on the isentropic trajectories in the phase diagram are shown to be consistent with the recent lattice results. Our nuclear equations of states are to be considered as an input to the dynamical models describing the production and the time evolution of a thermalized medium created in heavy ion collisions in a broad energy range from SIS up to LHC.Comment: 13 pages, 11 figure

The Final Fate of the Rolling Tachyon

We propose an alternative interpretation of the boundary state for the rolling tachyon, which may depict the time evolution of unstable D-branes in string theory. Splitting the string variable in the temporal direction into the classical part, which we may call "time" and the quantum one, we observe the time dependent behaviour of the boundary. Using the fermion representation of the rolling tachyon boundary state, we show that the boundary state correctly describes the time-dependent decay process of the unstable D-brane into a S-brane at the classical level.Comment: 9 pages, revte

Involve Children and Parents in Clinical Studies

Contains fulltext : 218569.pdf (publisher's version ) (Open Access

Wormholes in AdS

We construct a few Euclidean supergravity solutions with multiple boundaries. We consider examples where the corresponding boundary field theory is well defined on each boundary. We point out that these configurations are puzzling from the AdS/CFT point of view. A proper understanding of the AdS/CFT dictionary for these cases might yield some information about the physics of closed universes.Comment: 38 pages, 2 figures, harvmac. v2: minor typos corrected and references adde