November 1999 arXiv papers — page 5

A. G. Ramm

It is found what part of the fixed-energy phase shifts allows one to recover uniquely a compactly supported potential. For example, the knowledge of all phase shifts with even angular momenta is sufficient to recover the above potential.

A. G. Ramm

Property C stands for completeness of the set of products of solutions to homogeneous linear differential equations. property C is proved in various formulations for Schrödinger operators. Many applications of this property to inverse problems and inverse scattering problems are given. It is shown what part of the fixed-energy phase shifts determines a compa

Juergen Eichhorn

There are a least uncountably many diffeomorphism types for open manifolds. Hence the classification problem is extremely difficult. We proceed as follows: We define several uniform structures of proper metric spaces and consider their arc components. Any open complete manifold (M^n,g) defines such a component. Hence the classification amounts to two steps.

Gabor Elek

We investigate an analogue of the L^2-Betti numbers for amenable linear subshifts. The role of the von Neumann dimension shall be played by the topological entropy.

A. M. Gavrilik, N. Z. Iorgov

The nonstandard q-deformed algebras U'_q(so_n) are known to possess q-analogues of Gel'fand-Tsetlin type representations. For these q-algebras, all the Casimir elements (corresponding to basis set of Casimir elements of so(n)) are found, and their eigenvalues within irreducible representations are given explicitly.

M. Scheunert, R. B. Zhang

Invariant integrals on Hopf superalgebras, in particular, the classical and quantum Lie supergroups, are studied. The uniqueness (up to scalar multiples) of a left integral is proved, and a super version of Maschke's theorem is discussed. A construction of left integrals is developed for classical and quantum Lie supergroups. Applied to several classes o

T. Gomez

This is an expository article on the theory of algebraic stacks. After introducing the general theory, we concentrate in the example of the moduli stack of vector budles, giving a detailed comparison with the moduli scheme obtained via geometric invariant theory.

T. Gomez, I. Sols

Roughly speaking, a conic bundle is a surface, fibered over a curve, such that the fibers are conics (not necessarily smooth). We define stability for conic bundles and construct a moduli space. We prove that (after fixing some invariants) these moduli spaces are irreducible (under some conditions). Conic bundles can be thought of as generalizations of ortho

Vestislav Apostolov, Tedi Draghici

We study the question of integrability of a compatible almost complex structure on a compact symplectic 4-manifold, under various natural assumptions on the curvature of the associated almost Kahler metric.

Luis O'Shea, Reyer Sjamaar

The main result of this paper is a ``real form'' of Kirwan's convexity theorem, which in the abelian case was proved earlier by Duistermaat. We apply our result to flag varieties of real semisimple groups and obtain eigenvalue inequalities, which generalize inequalities found by Weyl, Ky Fan, Kostant, Klyachko, and many others.

Arkady Berenstein, Reyer Sjamaar

Consider a compact Lie group and a closed subgroup. Generalizing a result of Klyachko, we give a necessary and sufficient criterion for a coadjoint orbit of the subgroup to be contained in the projection of a given coadjoint orbit of the ambient group. The criterion is couched in terms of the ``relative'' Schubert calculus of the flag varieties of th

A. R. Lugo, E. F. Moreno, F. A. Schaposnik

We find monopole solutions for a spontaneously broken SU(2)-Higgs system coupled to gravity in asymptotically anti-de Sitter space. We present new analytic and numerical results discussing,in particular, how the gravitational instability of self-gravitating monopoles depends on the value of the cosmological constant.

George Leibbrandt, Jimmy D. Williams

The complete two-loop correction to the quark propagator, consisting of the spider, rainbow, gluon bubble and quark bubble diagrams, is evaluated in the noncovariant light-cone gauge (lcg). (The overlapping self-energy diagram had already been computed.) The chief technical tools include the powerful matrix integration technique, the n^*-prescription for the

S. Meljanac, M. Milekovic, R. Ristic

We critically examine a recent suggestion that "ambiguous" statistics is equivalent to infinite quon statistics and that it describes a dilute, nonrelativistics ideal gas of extremal black holes. We show that these two types of statistics are different and that the description of extremal black holes in terms of "ambiguous" statistics cannot

M. M. Sheikh-Jabbari

In this paper we study T-duality for open strings ending on branes with non-zero B-field on them from the point of view of canonical transformations. For the particular case of type II strings on the two torus we show that the $Sl(2,Z)_N$ transformations can be understood as a sub-class of canonical transformations on the open strings in the B-field backgrou

Jnanadeva Maharana

The purpose of this short review is to present progresses in string theory in the recent past. There have been very important developments in our understanding of string dynamics, especially in the nonperturbative aspects. In this context, dualities play a cardinal role. The string theory provides a deeper understanding of the physics of special class of bla

Changhyun Ahn, Soo-Jong Rey

Near-horizon geometry of coincident M2-branes at a conical singularity is related to M-theory on AdS4 times an appropriate seven-dimensional manifold X7. For X_7=N^{0,1,0}, squashing deformation is known to lead to spontaneous (super) symmetry breaking from N=(3, 0) to N=(0, 1) in gauged AdS4 supergravity. Via AdS/CFT correspondence, it is interpreted as ren

Axel Weber

The effective Hamiltonian introduced many years ago by Bloch and generalized later by Wilson, appears to be the ideal starting point for Hamiltonian perturbation theory in quantum field theory. The present contribution derives the Bloch-Wilson Hamiltonian from a generalization of the Gell-Mann-Low theorem, thereby enabling a diagrammatic analysis of Hamilton

Ioannis P. Zois

We introduce a Lagrangian density for M-Theory which is purely topological using Gelfand-Fuchs cohomology. Next we calculate the partition function which indeed gives topological invariants that can be expressed via the Ray-Singer analytic torsion.

Felix Sefkow

Recent results from H1 and ZEUS on heavy flavour production at HERA are reviewed

V. A. Kudryavtsev, E. V. Korolkova, N. J. C. Spooner

We revise the process of muon pair production by high-energy muons in rock using the recently published cross-section. The three-dimensional Monte Carlo code MUSIC has been used to obtain the characteristics of the muon bundles initiated via this process. We have compared them with those of conventional muon bundles initiated in the atmosphere and shown that

T. S. Evans, M. Ivin, M. Mobius

We use an optimised perturbation expansion called the linear delta-expansion to study the phase transition in a Higgs sector with a continuous symmetry and large couplings. Our results show how to use this non-perturbative method successfully for such problems. We also show how to simplify the method without losing any flexibility.

M. Beneke

In this review I cover recent developments concerning the construction of non-relativistic effective theories for perturbative heavy quark-antiquark systems and heavy quark mass definitions. I then discuss next-to-next-to-leading order results on quarkonium masses and decay, top quark pair production near threshold and QCD sum rules for $Υ$ mesons.

Elena Accomando, Alessandro Ballestrero, Ezio Maina

We generalize the inclusion of the imaginary parts of the fermionic one-loop corrections for processes with unstable vector bosons to the case of massive external fermions and non conservation of weak currents. We study the effect of initial and final state fermion masses in single W production in connection with the gauge-invariant treatment of the finite-w

Galit Eyal

Supersymmetric models with an approximate CP, $10^{-3} \lsim ϕ_{CP} \ll 1$, are a viable framework for the description of nature. The full high energy theory has exact CP and horizontal symmetries that are spontaneously broken with a naturally induced hierarchy of scales, $Λ_{CP} \ll Λ_{H}$. Consequently, the effective low energy theory, that is the supersym

Paul Hoyer

This is an introductory review of central topics in hadron physics that are addressed by high intensity, continuous electron beam facilities in the multi-GeV range. Exclusive processes are a crucial tool for increasing our knowledge of hadron wave functions beyond what can be learned from studies of hard inclusive processes. Data shows precocious scaling, su

M. Garcia Perez, T. G. Kovacs, P. van Baal

By studying the non-linear effects of overlapping instanton pairs we address difficulties in the identification of instanton distributions when the average instanton size is comparable to the average distance. For the exact charge two solution, we study how its parametrisation relates to a description in terms of individual instantons. There exist two dual s

R. Rosenfelder, A. W. Schreiber

We point out that the scalar Wick-Cutkosky model (with $χ^2 ϕ$ interaction) used in this study has been known for a long time to be unstable. However, the numerical results presented in this paper do not show any sign of this instability which casts some doubt on their reliability. We compare with the worldline variational approach.

Elena Accomando

The status of four and six fermion event generators for Standard Model processes at present and future e^+e^- colliders is briefly reviewed.

G. Passarino

A generalization of the Fermion-Loop scheme is introduced to account for external, non-conserved, currents. Complete Dyson re-summed transitions are introduced, including the contributions from the Higgs-Kibble ghosts in the 't Hooft-Feynman gauge. Running vector boson masses are introduced and their relation with the corresponding complex poles are inve

N. Haba, Y. Matsui, N. Okamura

In the case of two generation neutrinos, the energy-scale dependence of the lepton-flavor mixing matrix with Majorana phase can be governed by only one parameter r, which is the ratio between the diagonal elements of neutrino mass matrix. By using this parameter r, we derive the analytic solutions to the renormalization group equations of the physical parame

S. Sultansoy

Options for future lp, lA, gamma-p, gamma-A and FEL gamma-A colliders are discussed

Sergio Caracciolo, Maria Serena Causo, Giovanni Ferraro, Mauro Papinutto

We introduce several bilocal algorithms for lattice self-avoiding walks that provide reasonable models for the physical kinetics of polymers in the absence of hydrodynamic effects. We discuss their ergodicity in different confined geometries, for instance in strips and in slabs. A short discussion of the dynamical properties in the absence of interactions is

Atsushi Yamada

We pursue Ginsparg and Wilsons' block spin approach in the derivation of the Ginsparg-Wilson relation and study the correspondence of the eigenmodes of the Dirac operators in the continuum and lattice theories. After introducing a suitable cut-off in the continuum theory, we identify unphysical modes of the lattice Dirac operator which do not correspond

Gianluca Cruciani

An efficient approach to tensor perturbation calculations by proper use of computer algebra methods is described, reaching the sufficient generality required for a comprehensive analysis of the Schwarzschild and Reissner-Nordstroem metric stability.

Mauricio Bellini, Pablo D. Sisterna, Roberto R. Deza

Within the framework of stochastic inflationary cosmology we derive steady-state distributions P_c(V) of domains in comoving coordinates, under the assumption of slow-rolling and for two specific choices of the coarse-grained inflaton potential $V(Φ)$. We model the process as a Starobinsky-like equation in V-space plus a time-independent source term P_w(V) w

Sung-Won Kim

There are two effects of extra matter fields on the Lorentzian traversable wormhole. The ``primary effect'' says that the extra matter can afford to be a part of source or whole source of the wormhole when the wormhole is being formed. Thus the matter does not affect the stability of wormhole and the wormhole is still safe. If the extra matter is ext

Soma Mukherjee, Lee Samuel Finn

We describe the design of a Kalman filter that identifies suspension violin modes in an interferometric gravitational wave detectors data channel. We demonstrate the filter's effectiveness by applying it to data taken on the LIGO~40M prototype.

Luis P. Chimento, Alejandro S. Jakubi, Diego Pavon

The stability of the de Sitter era of cosmic expansion in spatially curved homogeneous isotropic universes is studied. The source of the gravitational field is an imperfect fluid such that the parameters that characterize it may change with time. In this way we extend our previous analysis for spatially-flat spaces as well as the work of Barrow.

Ugur Tirnakli

In this study, using q-generalized bit cumulants (q is the nonextensivity parameter of the recently introduced Tsallis statistics), we investigate the asymmetric unimodal maps. The study of the q-generalized second cumulant of these maps allows us to determine, for the first time, the dependence of the inflexion paremeter pairs (z_1,z_2) to the nonextensivit

Allan Griffin

This paper is based on three tutorial lectures given at the CRM Summer School in Banff, Alberta, June 27-July 10, 1999 on "Theoretical Physics at the End of the Twentieth Century". They will be published by Springer-Verlag. Lecture I gives a quick overview of recent studies of BEC in trapped atomic gases and reviews some properties of a trapped non-i

O. Benichou, M. Moreau, G. Oshanin

In this paper we study the kinetics of diffusion-limited, pseudo-first-order A + B -> B reactions in situations in which the particles' intrinsic reactivities vary randomly in time. That is, we suppose that the particles are bearing "gates" which interchange randomly and independently of each other between two states - an active state, when the r

M. V. Yablonskikh, A. V. Ezhov, V. I. Grebennikov, Yu. M. Yarmoshenko

The results of fluorescence measurements of magnetic circular dichroism (MCD) in Mn L_2,L_3 X-ray emission and absorption for Heusler alloys NiMnSb and Co2MnSb are presented. Very intense resonance Mn L_3 emission is found at the Mn 2p_3/2 threshold and is attributed to a peculiarity of the threshold excitation in materials with the half-metallic character o

A. Di Lorenzo, Rosario Fazio, F. W. J. Hekking, G. Falci

We study the spin susceptibility chi of a small, isolated superconducting grain. Due to the interplay between parity effects and pairing correlations, the dependence of chi on temperature T is qualitatively different from the standard BCS result valid in the bulk limit. If the number of electrons on the grain is odd, chi shows a re-entrant behavior as a func

S. Montangero, L. Fronzoni, P. Grigolini

We address the problem of applying the Kolmogorov-Sinai method of entropic analysis, expressed in a generalized non-extensive form, to the dynamics of the logistic map at the chaotic threshold, which is known to be characterized by a power law rather than exponential sensitivity to initial conditions. The computer treatment is made difficult, if not impossib

T. Schneider, J. M. Singer

We analyze recent measurements by Ooi et al. of the angular dependence of the first order vortex phase transition in Bi_2Sr_2CaCu_2O_{8+y}. The experimental findings of these authors are interpreted in terms of a 2D versus 3D scaling approach. Invoking a crossover from a 3D to a 2D scaling approach, it shown, that the apparent failure of a 3D scaling approac

Omri Gat, Zeev Olami

We study the transport and localization properties of scalar vibrations on a lattice with random bond strength by means of the transfer matrix method. This model has been recently suggested as a means to investigate the vibrations and heat conduction properties of structural glasses. In three dimensions we find a very rich phase diagram. The delocalization t

R. Brak, A. Owczarek

The free fermion condition of the six-vertex model provides a 5 parameter sub-manifold on which the Bethe Ansatz equations for the wavenumbers that enter into the eigenfunctions of the transfer matrices of the model decouple, hence allowing explicit solutions. Such conditions arose originally in early field-theoretic S-matrix approaches. Here we provide a co

Yasutami Takada

Based on an exact expression for the self-energy of the Jahn-Teller polaron, we find that symmetry of pseudospin rotation makes the vertex correction much less effective than that for the Holstein polaron. This ineffectiveness brings about a smaller effective mass m^* and a quantitatively differenent large-to-small polaron crossover, as examined by exact dia

W. Stephan, B. W. Southern

We report a Monte Carlo study of the classical antiferromagnetic Heisenberg model with easy axis anisotropy on the triangular lattice. Both the free energy cost for long wavelength spin waves as well as for the formation of free vortices are obtained from the spin stiffness and vorticity modulus respectively. Evidence for two distinct Kosterlitz-Thouless typ

I. V. Stasyuk, R. R. Levitskii, I. R. Zachek, A. P. Moina

Within the four-particle cluster approximation for the proton ordering model we study the influence of shear stress $σ_6$ on the phase transition, static dielectric, elastic and thermal properties of deuterated KD2PO4 type ferroelectrics. Thermodynamic potentials and physical characteristics of the crystals in the presence of stress $σ_6$ are calculated. Num

S. S. Banerjee

The phenomenon of superconductivity was discovered in 1911, however, the methodology to classify and distinguish type-II superconductivity was established only in late fifties after Abrikosov's prediction of a flux line lattice in 1957. The advent of high temperature superconductors (HTSC) in 1986 focused attention onto identifying and classifying other

J. N. Reeves, P. T. O'Brien, S. Vaughan, D. Law-Green

We present quasi-simultaneous ASCA and RXTE observations of the most luminous known AGN in the local (z<0.3) Universe, the recently discovered quasar PDS 456. Multiwavelength observations have been conducted which show that PDS 456 has a bolometric luminosity of 10^47 erg/s peaking in the UV part of the spectrum. In the X-ray band the 2-10 keV (rest-frame) l

Peter D. Barthel, Marianne Vestergaard, Colin J. Lonsdale

VLA imaging at kiloparsec-scale resolution of sixteen core-dominated radio-loud QSOs is presented. Many objects appear to display variable radio emission and their radio morphologies are significantly smaller than those of steep-spectrum quasars, consistent with these objects being observed at sight lines close to their (relativistic, $γ\approx$ 4-7) jet axe

V. Ripepi, G. Russo, G. Bono, M. Marconi

Direct measurements of Cepheid radii are a key for understanding the physical structure of these variables, and in turn for constraining their pulsation properties. In this paper we discuss the numerical experiments we performed for testing the accuracy of Cepheid radii obtained by adopting both the pure Baade-Wesselink (BW) method and the revised CORS metho

Fabien Casse, Jonathan Ferreira

We present steady-state calculations of self-similar magnetized accretion discs driving cold, adiabatic, non-relativistic jets. For the first time, both the magnetic torque due to the jets and a turbulent &#34;viscous&#34; torque are taken into account. This latter torque allows a dissipation of the accretion power as radiation at the disc surfaces, while th

S. Hony, L. B. F. M. Waters, P. A. Zaal, A. de Koter

We present the 2.4-45 micrometer ISO-SWS spectrum of the Be star gamma Cas (B0.5 IVe). The spectrum is characterised by a thermal continuum which can be well fit by a power-law S_nu ~ nu^0.99 over the entire SWS wavelength range. For an isothermal disc of ionized gas with constant opening angle, this correponds to a density gradient rho(r) ~ r^(-2.8). We rep

M. Brüggen

In the solar convection zone acoustic waves are scattered by turbulent sound speed fluctuations. In this paper the scattering of waves by convective cells is treated using Rytov&#39;s technique. Particular care is taken to include diffraction effects which are important especially for high-degree modes that are confined to the surface layers of the Sun. The

M. Bruscoli, A. Ferrara, R. Fabbri, B. Ciardi

We calculate the secondary anisotropies in the CMB produced by inhomogeneous reionization from simulations in which the effects of radiative and stellar feedback effects on galaxy formation have been included. This allows to self-consistently determine the beginning ($z_i\approx 30$), the duration ($ δz\approx 20$) and the (nonlinear) evolution of the reioni

James R. Murray

We consider the precession rates of eccentric discs in close binaries, and compare theoretical predictions with the results of numerical disc simulations and with observed superhump periods. A simple dynamical model for precession is found to be inadequate. For mass ratios less than approximately 1/4 a linear dynamical model does provide an upper limit for d

Makoto Hattori, Keiichi Umetsu

We have shown that there exists low-frequency growing modes driven by a global temperature gradient in electron and ion plasmas, by linear perturbation analysis within the frame work of plasma Kinetic theory. The driving force of the instability is the local deviation of the distribution function from the Maxwell-Boltzmann due to global temperature gradient.

I. Marquez, G. B. Lima Neto, H. Capelato, F. Durret

We have analyzed a sample of galaxies belonging to three clusters: Coma, Abell 85, and Abell 496 (real galaxies) and a sample of simulated elliptical galaxies formed in a hierarchical merging scheme (virtual galaxies). We use the Sersic law to describe their light profile. The specific entropy (Boltzmann-Gibbs definition) is then calculated supposing that th

A. Melchiorri, P. A. R. Ade, P. de Bernardis, J. J. Bock

We use the angular power spectrum of the Cosmic Microwave Background, measured during the North American test flight of the BOOMERANG experiment, to constrain the geometry of the universe. Within the class of Cold Dark Matter models, we find that the overall fractional energy density of the universe, Omega, is constrained to be 0.85 < Omega < 1.25 at the 68%

Axel Krause

In an earlier paper, Alvarez, Alvarez-Gaume, Barbon and Lozano pointed out, that the only way to &#34;flatten&#34; negative curvature by means of a T-duality is by introducing an appropriate, non-constant NS-NS B-field. In this paper, we are investigating this further and ask, whether it is possible to T-dualize AdS_d space to flat space with some suitably c

Gennaro Corcella

I discuss the feasibility of measuring the top quark mass by the using of final states with leptons and J/ψat hadron colliders. I also investigate the impact of matrix-element corrections to the HERWIG simulation of top decays.

J. -M. Chung, B. K. Chung

The renormalization group method is applied to the three-loop effective potential of the massive $ϕ^4$ theory in the $\bar{\rm MS}$ scheme in order to obtain the next-next-next-to-leading logarithm resummation. For this, we exploit four-loop parts of the renormalization group functions $β_λ$, $γ_m$, $γ_ϕ$, and $β_Λ$, which were already given to five-loop ord

V. Gurarie, A. W. W. Ludwig

We discuss the structure of 2D conformal field theories (CFT) at central charge c=0 describing critical disordered systems, polymers and percolation. We construct a novel extension of the c=0 Virasoro algebra, characterized by a number b measuring the effective number of massless degrees of freedom, and by a logarithmic partner of the stress tensor. It is ar

Xiaofeng Guo, Jianwei Qiu, Xiaofei Zhang

We derive the nuclear dependence coefficient $α(q_T)$ for Drell-Yan and J/$ψ$ production. We show that at small $q_T$, the $α(q_T)$ is given by an universal functional form: $α(q_T)=a+b q_T^2$, and the parameters $a$ and $b$ are completely determined by either perturbatively calculable or independently measurable quantities. This universal functional form $α

J. Ruostekoski

We propose a method of generating skyrmion vortices in a pair of Bose-Einstein condensates occupying two internal states of the same atom. We show that a variety of different periodic arrays of vortices may be prepared with an appropriate superposition of orthogonal standing electromagnetic waves inducing a coherent coupling between the two condensates.

Milena Imamovic-Tomasovic, Allan Griffin

Using the Kadanoff-Baym non-equilibrium Green's function formalism, we derive kinetic equations for the non-condensate atoms at finite temperatures which include the effect of binary collisions between atoms. The effect of collisions is included using the second-order self-energy given by the Beliaev (gapless) approximation. We limit our discussion to finite

M. Laine, M. Shaposhnikov

We complete an existing result for how the baryon asymmetry left over after a period of full thermal equilibrium depends on different lepton asymmetries.

A. H. Chamseddine, W. A. Sabra

Magnetic BPS string solutions preserving quarter of supersymmetry are obtained for all abelian gauged d=5 N=2 supergravity theories coupled to vector supermultiplets. Due to a ``generalised Dirac quantization&#39;&#39; condition satisfied by the minimized magnetic central charge, the string metric takes a universal form for all five dimensional gauged theori

M. G. Ryskin, A. G. Shuvaev

Classical pion field similar to Disoriented Chiral Condensate (DCC) is considered in the presence of the external source. This field is similar to DCC in the sense that its isotopic orientation is specified with a single vector at the whole space. We study the classical field solutions in the nonlinear sigma-model both in the chiral limit with massless pion

Z. Bern, L. Dixon, D. C. Dunbar, M. Perelstein

We review the relations that have been found between multi-loop scattering amplitudes in gauge theory and gravity, and their implications for ultraviolet divergences in supergravity.

John A. Gowan

The principles of energy, symmetry, entropy, and causality conservation are discussed in a &#34;Tetrahedron Model&#34; of a conceptually complete &#34;T.O.E.:&#34; &#34;The charges of matter are the symmetry debts of light&#34; (Noether&#39;s Theorem). Symmetry debts for each force as well as gravitation&#39;s conservation roles are considered. Special atten

Y. S. Myung, Gungwon Kang, H. W. Lee

We calculate the effect of noncommutative spacetime on the greybody factor on the supergravity side. For this purpose we introduce a system of D3-branes with a constant NS $B$-field along their world volume directions ($x_2, x_3$). Considering the propagation of minimally coupled scalar with non-zero momentum along($x_2, x_3$), we derive an exact form of the

N. Ya. Ivanov, A. Capella, A. B. Kaidalov

We analyze in the framework of pQCD the properties of the single spin asymmetry in heavy flavor production by linearly polarized photons. At leading order, the parallel- perpendicular asymmetry in azimuthal distributions of both charm and bottom quark is predicted to be about 20% in a wide region of initial energy. Our analysis shows that the next-to-leading

R. Fisch

Monte Carlo simulations have been used to study a vortex-free XY ferromagnet with a random field or a random anisotropy on simple cubic lattices. In the random field case, which can be related to a charge-density wave pinned by random point defects, it is found that long-range order is destroyed even for weak randomness. In the random anisotropy case, which

S. Basak, Asit K. De

We investigate a U(1) lattice chiral gauge theory with domain wall fermions and compact gauge fixing. In the reduced model limit, our perturbative and numerical investigations show that there exist no extra mirror chiral modes. The longitudinal gauge degrees of freedom have no effect on the free domain wall fermion spectrum consisting of opposite chiral mode

Carlo Angelantonj, Ralph Blumenhagen

We study supersymmetric orientifolds where the world-sheet parity transformation is combined with a conjugation of some compact complex coordinates. We investigate their T-duality relation to standard orientifolds and discuss the origin of continuous and discrete moduli. In contrast to standard orientifolds, the antisymmetric tensor describes a continuous de

O. M. Bulashenko, J. M. Rubi, V. A. Kochelap

We investigate the current injection into a ballistic conductor under the space-charge limited regime, when the distribution function of injected carriers is an arbitrary function of energy F_c(epsilon). The analysis of the coupled kinetic and Poisson equations shows that the injected current fluctuations may be essentially suppressed by Coulomb correlations

K. C. Chou, W. Palmer, E. A. Paschos, Y. L. Wu

We present a general model-independent and rephase-invariant formalism that cleanly relates CP and CPT noninvariant observables to the fundamental parameters. Different types of CP and CPT violations in the K^0-, B^0-, B_s^0- and D^0-systems are explicitly defined. Their importance for interpreting experimental measurements of CP and CPT violations is emphas

W. Grimus, H. Neufeld

We extend the Standard Model by adding a second Higgs doublet and a right-handed neutrino singlet with a heavy Majorana mass term. In this model, there are one heavy and three light Majorana neutrinos with a mass hierarchy m_3 >> m_2 >> m_1 such that that only m_3 is non-zero at the tree level and light because of the seesaw mechanism, m_2 is generated at th

Martin G. Harris, John F. Wheater

We show how to determine the unknown functions arising when the peeling decomposition is applied to multi-critical matter coupled to two-dimensional quantum gravity and compute the loop-loop correlation functions. The results that $η=2+2/(2K-3)$ and $ν=1-3/2K$ agree with the slicing decomposition, and satisfy Fisher scaling.

Andal Narayanan, Hema Ramachandran

The time evolution equations for average values of population and relative phase of a strongly coupled two component BEC is derived analytically. The two components are two hyper-fine states coupled by an external laser that drives fast Rabi oscillations between these states. Specifically, this derivation incorporates the two-mode model proposed in [1] for t

Makoto Tsubota, Kenichi Kasamatsu

The Josephson effect in cyclically coupled Bose-Einstein condensates is studied theoretically. We analyze the simultaneous Gross-Pitaevskii equations with coupling terms between adjacent condensates. Depending on the initial relative phases between condensates, Josephson current flows cyclically to make a quantized vortex. Reducing the coupling between conde

Hiroaki Terashima

We examine a possibility that, when a black hole is formed, the information on the collapsed star is stored as the entanglement entropy between the outside and the thin region (of the order of the Planck length) of the inside the horizon. For this reason, we call this as the entanglement entropy of the black hole ``horizon&#39;&#39;. We construct two models,

B. Ananthanarayan, P. N. Pandita

We study the renormalization group evolution and infra-red stable fixed points of the Yukawa couplings and the soft supersymmetry breaking trilinear couplings of the minimal supersymmetric standard model with baryon and lepton number (and R-parity) violation involving the heaviest generations. We show analytically that in the Yukawa sector there is only one

Makoto Katori, Norio Konno, Hideki Tanemura

We consider survival probabilities for the discrete time process in one dimension, which is known as the Domany-Kinzel model. A convergence theorem for infinite systems can be obtained in the nonattractive case.

D. C. Cabra, M. D. Grynberg

We investigate the ground state magnetization plateaux appearing in spin 1/2 two-leg ladders built up from dimerized antiferromagnetic Heisenberg chains and dimerized zig-zag interchain couplings. Using both Abelian bosonization and Lanczos methods we find that the system yields rather unusual plateaux and exhibits massive and massless phases for specific ch

Yohanes Surya, Kam Chan Hin, T. C. Au Yeung, W. Z. Shangguan

We analyze Pion Nucleon Scattering up to 700 MeV using a simple, relativistic, unitary model\cite{1}. The kernel of the integral equation includes nucleon, roper, delta, D_13 as well as S_11 poles with their corresponding crossed pole terms approximated by contact interactions. The s- and p- wave phase shifts are calculated from the model and shown to agree

Lowell S. Brown

Physical processes ranging from the Lamb shift to the energy loss dE/dx of a charged particle traversing a plasma entail processes that occur over a wide range of energy or length scales. Different physical mechanisms dominate at one or the other end of this range. For example, in the energy loss problem, soft collisions that are screened by collective effec

S. Mayburov

The quantum measurement problem considered for measuring system (MS) model which consist of measured state S (particle), detector D and information processing device O. For spin chains and other O models the state evolution for MS observables measurements studied. It&#39;s shown that specific O states structure forbids the measurement of MS interference term

B. Bagchi, R. Roychoudhury

We construct an isospectrum systems in terms of a real and complex potential to show that the underlying PT symmetric Hamiltonian possesses a real spectrum which is shared by its real partner.

P. Deuar, W. J. Munro

We present a detection scheme which using imperfect detectors, and imperfect quantum copying machines (which entangle the copies), allows one to extract more information from an incoming signal, than with the imperfect detectors alone.

Akira Shimizu

Quantum information theory is closely related to quantum measurement theory because one must perform measurement to obtain information on a quantum system. Among many possible limits of quantum measurement, the simplest ones were derived directly from the uncertainty principles. However, such simple limits are not the only limits. I here suggest a new limit

A. A. Kornyshev, S. Leikin

Using an exact solution for the pair interaction potential, we show that long, rigid, chiral molecules with helical surface charge patterns have a preferential interaxial angle ~((RH)^1/2)/L, where L is the length of the molecules, R is the closest distance between their axes, and H is the helical pitch. Estimates based on this formula suggest a solution for

Tom Ostoma, Mike Trushyk

We propose experiments that might be set up to detect the increase in the velocity of light in a vacuum in the laboratory frame for photons travelling between (and perpendicular to) the Casimir plates in a vacuum. The Casimir plates are two closely spaced, conductive plates, where an attractive force is observed to exist between the plates called the &#39;Ca

Alexander A. Vlasov

In nonrelativistic approximation one-dimensional motion of Sommerfeld sphere in the case of potential barrier is numerically investigated. The effect of classical tunneling is confirmed once more - Sommerfeld sphere overcomes the barrier and finds itself in the forbidden, from classical point of view, area.

M. Stewart Siu, Dmitry Budker

When a substance that shrinks in volume as it solidifies (for example, lead) is melted in a container and then cooled, a deep hole is often found in the center after resolidification. We use a simple model to describe the shape of the pipe and compare it with experimental results.