bluuebunny/crossref_metadata_2025 huggingface dataset:
LIGHTFRONT HAMILTONIAN STRUCTURES FOR THE NONLINEAR SIGMA MODEL
Authors: DAS ASHOK
Published: September 2003

We derive the Dirac brackets for the O(N) nonlinear sigma model in the lightfront description with and without constraint. We bring out various subtleties that arise including the fact that antiperiodic boundary condition seems to be preferred.
ON THE AREA OPERATORS OF THE HUSAIN–KUCHAŘ–ROVELLI MODEL AND CANONICAL/LOOP QUANTUM GRAVITY
Authors: AMELINO-CAMELIA GIOVANNI
Published: September 2003

We investigate the relation between an operative definition of the area of a surface specified by matter fields and the area operators recently introduced in the canonical/loop approach to quantum gravity and in Rovelli's variant of the Husain–Kuchař quantum gravity toy model. The results suggest that the discreteness of the spectra of the area operators might not be observable.
RSFP PREDICTIONS FOR TRANSVERSE SOLAR MAGNETIC FIELD DISTRIBUTION FROM SOLAR NEUTRINO DATA
Authors: CHAUHAN B. C. , PANDEY U. C. , DEV S.
Published: September 2003

Even though the standard solar model (SSM) has been very successful in predicting the thermal and nuclear evolution of the Sun, it does not throw enough light on solar magnetic activity. In the absence of a generally accepted theory of solar dynamo, various general arguments have been put forth to constrain solar magnetic fields. In the absence of reliable knowledge of solar magnetic fields from available astrophysical data, it may be worthwhile to constrain the solar magnetic fields from solar neutrino observations assuming Resonant Spin-Flavor Precession (RSFP) to be responsible for the solar neutrino deficit. The configuration of solar magnetic field derived in this work is in reasonably good agreement with the magnetic field distribution proposed by Akhmedov et al. (Sov. Phys. JETP68, 250 (1989)). However, the magnetic field distribution in the radiation zone used by Pulido (Phys. Rep.211, 167 (1992)) is ruled out. The magnitude of the magnetic field in the radiation and convective zones of the Sun are very sensitive to the value chosen for the neutrino magnetic moment. However, any change in the value of neutrino magnetic moment does not affect the magnetic field distribution as it only scales the magnetic field strength at different points by the same amount.
NON-RIEMANNIAN COSMIC WALLS AS BOUNDARIES OF SPINNING MATTER WITH TORSION
Authors: GARCIA DE ANDRADE L. C.
Published: September 2003

An example of a plane topological defect solution of linearized Einstein–Cartan (EC) field equation representing a cosmic wall boundary of spinning matter is given. The source of Cartan torsion is composed of two orthogonal lines of static polarized spins bounded by the cosmic plane wall. The Kopczyński–Obukhov–Tresguerres (KOT) spin fluid stress–energy current coincides with thin planar matter current in the static case. Our solution is similar to the Letelier solution of Einstein equation for multiple cosmic strings. Due to this fact we suggest that the lines of spinning matter could be analogous to multiple cosmic spinning string solution in EC theory of gravity. When torsion is turned off, a pure Riemannian cosmic wall is obtained.
TWO-POINT FUNCTIONS IN AFFINE SL(N) CURRENT ALGEBRA
Authors: RASMUSSEN JØRGEN
Published: September 2003

In this letter the explicit form of general two-point functions in affine SL (N) current algebra is provided for all representations, integrable or non-integrable. The weight of the conjugate field to a primary field of arbitrary weight is immediately read off.
QUANTUM TWO-PHOTON ALGEBRA FROM NON-STANDARD Uz(sl(2,ℝ)) AND A DISCRETE TIME SCHRÖDINGER EQUATION
Authors: BALLESTEROS ANGEL , HERRANZ FRANCISCO J. , PARASHAR PREETI
Published: September 2003

The non-standard quantum deformation of the (trivially) extended sl (2,ℝ) algebra is used to construct a new quantum deformation of the two-photon algebra h6 and its associated quantum universal R-matrix. A deformed one-boson representation for this algebra is deduced and applied to construct a first-order deformation of the differential equation that generates the two-photon algebra eigenstates in quantum optics. On the other hand, the isomorphism between h6 and the (1+1) Schrödinger algebra leads to a new quantum deformation for the latter for which a differential-difference realization is presented. From it, a time discretization of the heat-Schrödinger equation is obtained and the quantum Schrödinger generators are shown to be symmetry operators.
TWO-POINT FUNCTIONS IN AFFINE CURRENT ALGEBRA AND CONJUGATE WEIGHTS
Authors: RASMUSSEN JØRGEN
Published: September 2003

The two-point functions in affine current algebras based on simple Lie algebras are constructed for all representations, integrable or non-integrable. The weight of the conjugate field to a primary field of arbitrary weight is immediately read off.
DIMENSIONFUL DEFORMATIONS OF POINCARÉ SYMMETRIES FOR A QUANTUM GRAVITY WITHOUT IDEAL OBSERVERS
Authors: AMELINO-CAMELIA GIOVANNI
Published: September 2003

Quantum mechanics is revisited as the appropriate theoretical framework for the description of the outcome of experiments that rely on the use of classical devices. In particular, it is emphasized that the limitations on the measurability of (pairs of conjugate) observables encoded in the formalism of quantum mechanics reproduce faithfully the "classical-device limit" of the corresponding limitations encountered in (real or gedanken) experimental setups. It is then argued that devices cannot behave classically in quantum gravity, and that this might raise serious problems for the search of a class of experiments described by theories obtained by "applying quantum mechanics to gravity." It is also observed that using heuristic/intuitive arguments based on the absence of classical devices one is led to consider some candidate quantum gravity phenomena involving dimensionful deformations of the Poincaré symmetries.
ISOSPIN-BREAKING VACUUM-TO-π0, η PSEUDOSCALAR MATRIX ELEMENTS AT NEXT-TO-LEADING ORDER IN THE CHIRAL EXPANSION
Authors: MALTMAN KIM , WOLFE CARL E.
Published: September 2003

We employ chiral perturbation theory (ChPT) to evaluate the complete set of pseudoscalar matrix elements, <0|Pf|π0,η>, with Pf any of the flavor-diagonal pseudoscalar currents (f=u,d,s) to [Formula: see text], and to next-to-leading order in the chiral expansion. These matrix elements represent the basic input to a QCD sum rule analysis of isospin breaking in the πNN couplings using the three-point function method. We also discuss how one could use the results to construct a one-parameter family of interpolating fields for the π0, all of whose members have zero vacuum-to-η matrix element, and explain how this could in principle be used to provide nontrivial tests of the reliability of the assumptions underlying the use of three-point function method. It is shown that the isospin-breaking mixing parameters required for this construction receive significant corrections beyond leading order in the chiral expansion.
CONFINING PHASE IN SUSY SO(12) GAUGE THEORY WITH ONE SPINOR AND SEVERAL VECTORS
Authors: MARU NOBUHITO
Published: September 2003

We study the confining phase structure of [Formula: see text] supersymmetric SO(12) gauge theory with Nf≤7 vectors and one spinor. The explicit form of low-energy superpotentials for Nf≤7 are derived after gauge-invariant operators relevant in the effective theory are identified via gauge symmetry breaking pattern. The resulting confining phase structure is analogous to Nf≤Nc+1 SUSY QCD. Finally, we conclude with some comments on the search for duals to Nf≥8 SO(12) theory.
NUCLEAR EFFECTS ON SUPERFLUID NEUTRON STAR MATTER
Authors: DE BLASIO F. V. , LAZZARI G.
Published: September 2003

In the inner crust of a neutron star, the superfluid neutron liquid shares a fraction of the volume with neutron-rich nuclei and thus cannot be considered as uniform. We find that quasi-resonant states, due to elastic scattering with the effective nuclear potential wells, can enhance the neutron density of states at the Fermi surface for some values of the energy of the incident neutron. This may locally change the pairing energy gap of the superfluid neutrons up to a factor of three to four. We then discuss the smoother change of the neutron effective matrix element induced by the presence of the nuclei considering the case in which the superfluid coherence length is larger than the nuclear sizes. The results show that the value of the pairing gap as calculated for infinite systems is not directly the one that should be expected to exist in the crust of a neutron star and we work out an approximate formula for the gap taking into account both effects. The sudden change of the neutronic superfluid gap in localized crust shells due to the nuclear quasi-resonant states can have consequences for theories of the rotational and thermal evolution of neutron stars while the smooth, continuous variation of the effective matrix element can have implications for the cooling of the star.
IS THE LAW OF UNIVERSAL GRAVITATION VALID AT SHORT DISTANCES?
Authors: ONOFRIO ROBERTO
Published: September 2003

Recently, short-range macroscopic forces superimposed to gravity have been conjectured. We argue that their existence is unavoidable if gravity has to be merged with the other fundamental interactions within the currently accepted paradigms for unification. A first attempt to detect such forces in the macroscopic range using micromechanical resonators is reported, together with a discussion of further sensitivity improvements. Implications of the possible discovery of these new interactions in elementary particle physics and cosmology are outlined.
BLACK HOLES AND STRINGS: THE POLYMER LINK
Authors: KHURI RAMZI R.
Published: September 2003

Quantum aspects of black holes represent an important testing ground for a theory of quantum gravity. The recent success of string theory in reproducing the Bekenstein–Hawking black hole entropy formula provides a link between general relativity and quantum mechanics via thermodynamics and statistical mechanics. Here we speculate on the existence of new and unexpected links between black holes and polymers and other soft-matter systems.
COMMENTS ON THE REVIEW OF CP VIOLATION IN THE PARTICLE DATA BOOK
Authors: WU DAN-DI
Published: September 2003

Rephasing invariant formalism for the [Formula: see text] system is recommended for the Particle Data Group. This formalism is accurate and prevents possible errors in generalizing the formalism to other systems, as well as in using CKM matrices not included in the Particle Data Book.
MASS OF PERFECT FLUID BLACK SHELLS
Authors: ZLOSHCHASTIEV KONSTANTIN G.
Published: September 2003

The spherically symmetric singular perfect fluid shells are considered when their radii are equal to the event horizon (the black shells). We study their observable masses, depending at least on the three parameters, viz. the square speed of sound in the shell, instantaneous radial velocity of the shell at a moment when it reaches the horizon, and integration constant related to surface mass density. We discuss the features of black shells depending on the equation of state.
SELF-ACTION ON A CURRENT WITH INTERNAL STRUCTURE IN COSMIC STRING SPACE–TIMES
Authors: BEZERRA DE MELLO E. R. , BEZERRA V. B. , GRATS YU. V.
Published: September 2003

We calculate the topological self-energy of the stationary linear distribution of a four-current with zero total current and a charge per unit length in the space–time of a straight cosmic string. It is shown that if the structure of a current is determined in the first approximation by its electric and magnetic dipole moments, then the self-force is not equal to zero and the current is also affected by the action of a moment of force which has a topological nature. The generalization of the obtained results for the space–time of multiple cosmic string is also discussed.
LAX PAIRS FOR N=2,3 SUPERSYMMETRIC KdV EQUATIONS AND THEIR EXTENSIONS
Authors: KRIVONOS S. , PASHNEV A. , POPOWICZ Z.
Published: September 2003

We present the Lax operator for the N=3 KdV hierarchy and consider its extensions. We also construct a new infinite family of N=2 supersymmetric hierarchies by exhibiting the corresponding super Lax operators. The new realization of N=4 supersymmetry on the two general N=2 superfields, bosonic spin-1 and fermionic spin-1/2, is discussed.
QUASI-EXACTLY SOLVABLE RADIAL DIRAC EQUATIONS
Authors: BRIHAYE Y. , KOSINSKI PIOTR
Published: September 2003

In the background of a central Coulomb potential, the Schrödinger and Dirac equations lead to exactly solvable spectral problems. When the Schrödinger–Coulomb equation is supplemented by a Harmonic potential, the corresponding spectral problem still possesses a finite number of algebraic solutions: it is quasi-exactly solvable. In this letter we analyze the spectral problem corresponding to the Dirac–Coulomb problem supplemented by a linear radial potential and we show that it also leads to quasi-exactly solvable equations.
A NOTE ON SOFTLY BROKEN MQCD
Authors: BARBÓN J. L. F. , PASQUINUCCI A.
Published: September 2003

We consider generic MQCD configurations with matter described by semi-infinite D4-branes and softly broken supersymmetry. We show that the matter sector does not introduce supersymmetry breaking parameters so that the most relevant supersymmetry breaking operator at low energies is the gaugino mass term. By studying the run-away properties of these models in the decoupling limit of the adjoint matter, we argue that these softly broken MQCD configurations fail to capture the infrared physics of QCD at scales below the gaugino mass.
MEMBRANE, FOUR-BRANE AND DUAL COORDINATES IN THE M(ATRIX) THEORY COMPACTIFIED ON TORI
Authors: RYANG SHIJONG
Published: September 2003

In the M(atrix) theory by making the expansions of the matrices around the infinite membrane and four-brane solutions, we derive the three- and five-dimensional gauge theories in the dual space–times. The explicit forms of solutions yield the dual coordinates and each expansion is related to a toroidal compactification of the M(atrix) theory. We also analyze the expansion around the finite membrane. From the derived Lorentz and gauge-invariant actions, the gauge coupling constants are shown to be characterized by the volumes of tori.
U(N)-MONOPOLES ON KERR BLACK HOLE AND ITS ENTROPY
Authors: GONCHAROV YU. P.
Published: September 2003

We describe U(N)-monopoles (N>1) on Kerr black holes using the parameters of the moduli space of holomorphic vector U(N)-bundles over [Formula: see text] with the help of the Grothendieck splitting theorem. For N = 2,3 we obtain this description in an explicit form as well as the estimates for the corresponding monopole masses. This gives us a possibility to adduce some reasonings in favor of the existence of both a fine structure for Kerr black holes and the statistical ensemble tied with it which might generate the Kerr black hole entropy.
FOUR-DIMENSIONAL BLACK HOLES AND STRINGS WITH RESCALED TENSION
Authors: HALYO EDI
Published: September 2003

We give a microscopic description of extreme and near-extreme Reissner–Nordström black holes in four dimensions in terms of fundamental strings in a background of magnetic five branes and monopoles. The string oscillator numbers and tension are rescaled due to the Rindler space background with the string mass fixed. The entropy of the black holes is reproduced correctly by that of the string by taking into account the tension rescaling.
VACUUM POLARIZATION OF SUPERSYMMETRIC D-BRANE IN THE CONSTANT ELECTROMAGNETIC FIELD
Authors: KADOYOSHI TOMOKO , SUGAMOTO AKIO , NOJIRI SHIN'ICHI , ODINTSOV SERGEI D.
Published: September 2003

We study the vacuum polarization of supersymmetric toroidal D-brane placed in the constant electromagnetic field. Explicit calculation of the one-loop effective potential is performed for membrane with constant magnetic or electric background. We find that the one-loop potentials vanish as the effect of supersymmetry.
BARYOGENESIS IN AN SO(10) GUT MODEL WITH PATI–SALAM INTERMEDIATE SYMMETRY
Authors: BUCCELLA F. , PISANTI O. , ROSA L.
Published: September 2003

The possibility of generating the observed baryon asymmetry of the universe in an SO(10) gauge model with spontaneous symmetry breaking pattern [Formula: see text] is studied. We find it possible to generate a [Formula: see text], converting the leptonic number produced at the B- L breaking scale via the B+L violating processes mediated by sphalerons at the electroweak scale. The resulting picture is tested against the limit coming from experimental data: proton lifetime and neutrino oscillations.
CONSISTENCY CONDITIONS FOR 4-D REGULARIZATIONS
Authors: BATTISTEL O. A. , MOTA A. L. , NEMES M. C.
Published: September 2003

From the study of well-known divergent amplitudes we deduce three consistency conditions which are necessary and sufficient to eliminate ambiguities and symmetry violations. The conditions relate divergent integrals of the same degree of divergence and are automatically satisfied within the context of dimensional regularization. We show how the deduced consistency conditions can be satisfied in four-dimensional regularizations. An important conclusion of the present study is the possibility of working with 4-D regularization schemes which preserve the virtues of dimensional regularization avoiding, however, its restrictions.
COMMENTS ON THE BACKGROUND FIELD METHOD IN HARMONIC SUPERSPACE: NON-HOLOMORPHIC CORRECTIONS IN N=4 SYM
Authors: BUCHBINDER IOSEPH L. , KUZENKO SERGEI M.
Published: September 2003

We analyze the one-loop effective action of N=4 SYM theory in the framework of the bakground field formalism in N=2 harmonic superspace. For the case of onshell background N=2 vector multiplet we prove that the effective action is free of harmonic singularities. When the lowest N=1 superspace component of the N=2 vector multiplet is switched off, the effective action of N=4 SYM theory is shown to coincide with obtained by Grisaru et al. on the base of the N=1 background field method. We compute the leading non-holomorphic corrections to the N=4 SU (2) SYM effective action.
COMMENT ON THE DIFFERENTIAL CALCULUS ON THE QUANTUM EXTERIOR PLANE
Authors: ÇELIK SALIH , ÇELIK SULTAN A. , ARIK METIN
Published: September 2003

We give a two-parameter quantum deformation of the exterior plane and its differential calculus without the use of any R-matrix and relate it to the differential calculus with the R-matrix. We prove that there are two types of solutions of the Yang–Baxter equation whose symmetry group is GL p,q(2). We also give a two-parameter deformation of the fermionic oscillator algebra.
A CHAOTIC GRAVITATIONAL WAVE DETECTOR
Authors: ARGYRIS JOHN , CIUBOTARIU CORNELIU
Published: September 2003

In this letter we signalize the possibility of applying a quantum chaos as an element of high sensitivity which serves to detect small changes in length generated by gravitational waves. We propose the construction of a double-bar antenna with a coupling Josephson junction in its center-of-mass. In fact the new antenna is a single Josephson junction with massive bulk contacts, like a single-junction SQUID but with free ends. Computer experiments demonstrate that very small changes generated by the variation of the distance between the bulk plates of the junction capacitance will produce a variety of very different intermittency routes to chaos. A concrete numerical example illustrates the smallness of a quantum of chaos and thus the extraordinary sensitivity of the proposed method.
PRINCIPLES OF A NEW QUANTUM THEORY
Authors: SYROS C.
Published: September 2003

The principles of a random quantum theory (R-QT) which is alternatively time-asymmetric or time-symmetric if the quantization is Fermi–Dirac or Bose–Enstein, respectively are presented. Bohr's quantization rule is applied on the field-action integral. A time topological space, [Formula: see text], is mathematically defined in which the paradoxes in standard quantum theory are solved. The time "quantum", is created as a regular, positive into-map of an observed observable's change resulting from a fundamental interaction process. [Formula: see text] is constructed as the union of time elements and can be embedded disconnectedly in the continuous Newtonian universal time, [Formula: see text]. Six axioms are formulated characterizing the space–time and R-QT. The disconnectedness of the (κ×λκ)-fold time-space, [Formula: see text], imparts a kind of disconnectedness to the κ×λκ-fold space–times, [Formula: see text], and induces the chrono-topology. In chrono-topology the unitary, U, or non-measure preserving, R, dynamics, is implemented by means of a time evolution, "complex" operator, [Formula: see text]. It breaks down by means of Bohr quantization into: [Formula: see text][Formula: see text] coincides formally — apart from the spontaneous renormalization — with the time evolution operator in the standard QFT. [Formula: see text] is a novum and produces the Maxwell–Boltzmann energy level distribution in a non-Euclidean QFT. Compatibility between time-reversal invariance of the standard QT equations and irreversibility of some phenomena both in microcosmos and macrocosmos is obtained. The [Formula: see text]-evolution leads to a time's arrow on quantum-scale systems.
BARYON SPECTRA IN DEFORMED OSCILLATOR QUARK MODEL
Authors: HOSAKA A. , TOKI H. , TAKAYAMA M.
Published: September 2003

We study theoretically the baryon spectra in terms of a deformed oscillator quark (DOQ) model. This model is motivated by confinement of quarks and chiral symmetry breaking, which are the most important nonperturbative phenomena of QCD. The minimization of the DOQ Hamiltonian with respect to the deformation for each principal quantum number results in deformations for the intrinsic states of excited baryonic states. We find that the resulting baryon spectra agree very well with the existing experimental data including SU(3) baryons. The spatial deformation of the baryonic excited states carry useful information on the quark confinement and provide a clue to understand the confining mechanism.
ONE-PARTICLE AND COLLECTIVE ELECTRON SPECTRA IN HOT AND DENSE QED AND THEIR GAUGE DEPENDENCE
Authors: KALASHNIKOV O. K.
Published: September 2003

The one-particle electron spectrum is found for hot and dense QED and its properties are investigated in comparison with the collective spectrum. It is shown that the one-particle spectrum (in any case its zero momentum limit) is gauge-invariant, but the collective spectrum, being qualitatively different, is always gauge-dependent. The exception is the case m,μ=0 for which the collective spectrum long wavelength limit demonstrates the gauge invariance as well.
COMMENT ON PLANCK DISTRIBUTION OF COMPLEX-q BOSON GAS
Authors: JOHAL RAMANDEEP S. , GUPTA RAJ K.
Published: September 2003

Complex-q boson gas as an application of complex-q oscillator algebra is reinvestigated by using an algebra that was introduced recently by us 5 as an improvement over the earlier studies of Gupta et al.2 and Angelopoulou et al.3 The improvements are in terms of the use of Hermitian operators (real eigenvalues) and constant boson number. The formalism is therefore exact and results in the modifications of some of the approximate results of Gupta et al.2 A possible connection of the q-deformed, effective Planck constant to the (minimum) q-uncertainty relation is also discussed.
AGE CRISES, SCALAR FIELDS, AND THE APOCALYPSE
Authors: JACKSON J. C.
Published: September 2003

Recent observations suggest that Hubble's constant is large, to the extent that the oldest stars appear to have ages which are greater than the Hubble time, and that the Hubble expansion is slowing down, so that according to conventional cosmology the age of the Universe is less than the Hubble time. The concepts of weak and strong age crises (respectively t0<1/H0 but longer than the age inferred from some lower limit on q0, and t0>1/H0 and q0>0) are introduced. These observations are reconciled in models which are dynamically dominated by a homogeneous scalar field, corresponding to an ultra-light boson whose Compton wavelength is of the same order as the Hubble radius. Two such models are considered, an open one with vacuum energy comprising a conventional cosmological term and a scalar field component, and a flat one with a scalar component only, aimed respectively at weak and strong age crises. Both models suggest that anti-gravity plays a significant role in the evolution of the Universe.
RENORMALIZATION OF SCHRÖDINGER EQUATION AND WAVE FUNCTIONAL FOR RAPIDLY OSCILLATING FIELDS IN QCD
Authors: ZAREMBO K.
Published: September 2003

Background field method is used to perform renormalization group transformations for Schrödinger equation in QCD. The dependence of the ground state wave functional on rapidly oscillating fields is found.
WU–YANG MONOPOLES AND NON-ABELIAN SEIBERG–WITTEN EQUATIONS
Authors: DERELI T. , TEKMEN M.
Published: September 2003

Some exact solutions of the SU(2) Seiberg–Witten equations in Minkowski space–time are given.
GENERALIZED CONNECTION FORMALISM AND BRST COHOMOLOGY STRUCTURE FOR BF THEORIES
Authors: ABDESSELAM A. , TAHIRI M.
Published: September 2003

The non-Abelian BF theories in arbitrary dimensions are studied in a generalized connection formalism. This gives rise to the off-shell nilpotent BRST operator which permits construction of BRST exact quantum action. A set of operators satisfying the descent equations is derived from the generalized curvature; but it cannot lead to non-trivial observables. An off-shell superalgebra of Wess–Zumino type, containing the vector supersymmetry and the BRST symmetry, is also derived.
PHENOMENOLOGICAL BOUNDS ON B TO LIGHT SEMILEPTONIC FORM FACTORS
Authors: FALCONE D. , TANCREDI N. , TRAMONTANO F. , SANTORELLI P.
Published: September 2003

The form factors for the weak currents between B and light mesons are studied by relating them to the corresponding D form factors at [Formula: see text] according to HQET, by evaluating them at q2=0 by QCD sum rules, and by assuming a polar q2 dependence. The results found are consistent with the information obtained from exclusive non-leptonic two-body decays and, with the only exception of A1, with lattice calculations.
DESCRIPTION OF THE HIGHER MASSLESS IRREDUCIBLE INTEGER SPINS IN THE BRST APPROACH
Authors: PASHNEV A. , TSULAIA M.
Published: September 2003

The BRST approach is applied to describe the irreducible massless higher spins representation of the Poincaré group in arbitrary dimensions. The total system of constraints in such theory includes both first- and second-class constraints. The corresponding nil-potent BRST charge contains terms up to the seventh degree in ghosts.
A NEW APPROACH TO BLACK HOLE MICROSTATES
Authors: EPP RICHARD J. , MANN R. B.
Published: September 2003

If one encodes the gravitational degrees of freedom in an orthonormal frame field, there is a very natural first-order action one can write down (which in four dimensions is known as the Goldberg action). In this letter we will show that this action contains a boundary action for certain microscopic degrees of freedom living at the horizon of a black hole, and argue that these degrees of freedom hold great promise for explaining the microstates responsible for black hole entropy, in any number of space–time dimensions. This approach faces many interesting challenges, both technical and conceptual.
NONPERTURBATIVE SOLUTIONS OF THE SD EQUATION FOR AN ABELIAN GAUGE FIELD THEORY
Authors: MOGAMI TSUGUO
Published: September 2003

In this letter we present a mechanism in which new nonperturbative solutions of quantum electrodynamics in four dimensions is found. Two nonperturbative solutions are found for approximate Schwinger–Dyson equations. The mass ratio of the three solutions (one of them is the ordinary solution) is approximately 1: (8π/α)2/3 : 8π/α, which is close to the realistic mass ratio of e-, μ- and τ-.
REGULARIZING THE QUARK-LEVEL LINEAR σ-MODEL
Authors: DELBOURGO R. , SCADRON M. D. , RAWLINSON A. A.
Published: September 2003

We show that the finite difference, -iπ2m2, between quadratic and logarithmic divergent integrals ∫d4p[m2 (p2-m2)-2 - (p2-m2)-1], as encountered in the linear σ-model, is in fact regularization independent.
CHARGING SYMMETRIES AND LINEARIZING POTENTIALS FOR EINSTEIN–MAXWELL DILATON–AXION THEORY
Authors: HERRERA-AGUILAR ALFREDO , KECHKIN OLEG
Published: September 2003

We derive a set of complex potentials which linearize the action of charging symmetries of the stationary Einstein–Maxwell dilaton–axion theory.
THE IMPORTANCE OF TAU LEPTONS FOR SUPERSYMMETRY SEARCHES AT THE TEVATRON
Authors: WELLS JAMES D.
Published: September 2003

Supersymmetry is perhaps most effectively probed at the Tevatron through production and decay of weak gauginos. Most of the analyses of weak gaugino observables require electrons or muons in the final state. However it is possible that the gauginos will decay primarily to τ leptons, thus complicating the search for supersymmetry. The motivating reasons for high τ multiplicity final states are discussed in three approaches to supersymmetry model building: minimal supergravity, minimal gauge mediated supersymmetry, and more minimal supersymmetry. The concept of "e/μ/τ candidate" is introduced, and an observable with three e/μ/τ candidates is defined in analog to the trilepton observable. The maximum mass reach for supersymmetry is then estimated when gaugino decays to τ leptons have full branching fraction.
HAMILTONIAN FORMULATION OF JACKIW–PI THREE-DIMENSIONAL GAUGE THEORIES
Authors: DAYI ÖMER F.
Published: September 2003

A three-dimensional non-Abelian gauge theory was proposed by Jackiw and Pi to create mass for the gauge fields. However, the quadratic action obtained by switching off the non-Abelian interactions possesses more gauge symmetries than the original one, causing some difficulties in quantization. Jackiw and Pi proposed another action by introducing new fields, whose gauge symmetries are consistent with the quadratic part. It is shown that all of these theories have the same number of physical degrees of freedom in the Hamiltonian framework. Hence, as far as the physical states are considered, there is no inconsistency. Nevertheless, perturbation expansion is still problematic. To rectify this we propose to modify one of the constraints of the non-Abelian theory without altering its canonical Hamiltonian nor the number of physical states.
IWP SOLUTIONS FOR HETEROTIC STRING IN FIVE DIMENSIONS
Authors: HERRERA-AGUILAR ALFREDO , KECHKIN OLEG
Published: September 2003

We obtain extremal stationary solutions that generalize the Israel–Wilson–Perjés class for the low-energy limit of heterotic string theory with n≥ 3U(1) gauge fields toroidally compactified from five to three dimensions. A dyonic solution is obtained using the matrix Ernst potential (MEP) formulation and expressed in terms of a single real (3×3)-matrix harmonic function. By studying the asymptotic behavior of the field configurations, we define the physical charges of the field system. The extremality condition makes the charges saturate the Bogomol'nyi–Prasad–Sommmerfield (BPS) bound.
VIRTUAL SUPERSYMMETRIC CORRECTIONS IN e+e- ANNIHILATION
Authors: CLAVELLI L. , COULTER P. W. , SURGULADZE LEVAN R.
Published: September 2003

Depending on their masses, supersymmetric particles can affect various measurements in Z decay. Among these are the total width (or consequent extracted value of αs), enhancement or suppression of various flavors, and left–right and forward–backward asymmetries. The latter depend on squark mass splittings and are, therefore, a possible test of the supergravity related predictions. We calculate leading order corrections for these quantities considering in particular the case of light photino and gluino where the SUSY effects are enhanced. In this limit the effect on αs is appreciable, the effect on Rb is small, and the effect on the asymmetries is extremely small.
INELASTIC PHOTOPRODUCTION OF W-BOSON
Authors: KHAIRUL ALAM S. M. , HARUN AR RASHID A. M.
Published: September 2003

We study the WWγ vertex through the process γq→Wq′ where q denotes the quark at a future high energy collider. The differential cross-section for the photoproduction process γq→Wq′ is computed with both anomalous magnetic moment κ and electric quadrupole moment λ for the W-boson. The deep inelastic photoproduction of W± is also calculated in a quark-parton model.
UNIFICATION OF SU(2)⊗U(1) USING A GENERALIZED COVARIANT DERIVATIVE AND U(3)
Authors: CHAVES M. , MORALES H.
Published: September 2003

A generalization of the Yang–Mills covariant derivative, that uses both vector and scalar fields and transforms as a four-vector contracted with Dirac matrices, is used to simplify the Glashow–Weinberg–Salam model. Since SU(3) assigns the wrong hypercharge to the Higgs boson, it is necessary to use a special representation of U(3) to obtain all the correct quantum numbers. A surplus gauge scalar boson emerges in the process, but it uncouples from all other particles.
NEW CONSTRAINTS ON Rp VIOLATING COUPLINGS VIA SUSY ACCOMPANIED NEUTRINO EXCHANGE MECHANISM OF NEUTRINOLESS DOUBLE BETA DECAY
Authors: KANG SIN KYU
Published: September 2003

We consider ββ0ν decay induced by light Majorana neutrino exchange between decaying nucleons, accompanied by, in particular, the slepton exchange inside a nucleon. This contribution to ββ0ν is generated from the Rp violating terms and the mixing of the standard light neutrinos with neutral heavy particles or light sterile neutrinos. To determine the unknown mixing factor Δ, we take into account the four-neutrino model with three ordinary neutrinos and one sterile neutrino. Imposing the current experimental lower half-life limit, a set of constraints on [Formula: see text] and [Formula: see text] is obtained. Comparing with the limits on the products of the individual bounds on λ and λ′, we find that the former is stronger while the latter is weaker.
BÄCKLUND TRANSFORMATIONS IN 2-D DILATON GRAVITY
Authors: NAVARRO D. J. , NAVARRO-SALAS J.
Published: September 2003

We give a Bäcklund transformation connecting a generic 2-D dilaton gravity theory to a generally covariant free field theory. This transformation provides an explicit canonical transformation relating both theories.
QUANTUM LIOUVILLE FIELD THEORY ON A MANIFOLD WITH BOUNDARY
Authors: APIKYAN S. A.
Published: September 2003

This letter studies the quantum Liouville field theory on a manifold with boundary. The boundary conformal Ward identity (CWI) is written and its semiclassical approximation is analyzed. This establishes a method of finding the accessory parameters of the theory with boundary. The boundary structure constants of the theory are defined and the functional equations which determine them are derived.
TWO-DIMENSIONAL N=1,2 SUPERSYMMETRIC CHIRAL AND DUAL MODELS
Authors: CONSTANTINIDIS C. P. , TOPPAN F. , DEVECCHI F. P.
Published: September 2003

Two-dimensional N=1,2 supersymmetric chiral models and their dual extensions are introduced and canonically quantized. Working within a superspace formalism, the non-manifest invariance under 2D-super-Poincaré transformations is proven. The N=1,2 super-Virasoro algebras are recovered as current algebras. The non-anomalous quantum invariances under 1D-superdiffeomorphisms (for chiral models) and N=1,2 superconformal transformations (for dual models) are shown to be a consequence of an N=1,2 super-Coulomb gas representation.
ON METRIC DEPENDENCE OF VILKOVISKY–DEWITT EFFECTIVE POTENTIAL
Authors: KAO W. F. , LIN SHIH-YUIN
Published: September 2003

It is known that the Vilkovisky–DeWitt effective potential for Einstein gravity depends on the choice of the metric of configuration space. We will show that this metric dependence occurs not only in gauge field theories, but also in scalar fields as well as other field theories with "unnatural" initial choices of metric. This means that the problem of metric dependence relates to initial field parametrization but not gauge symmetry.
THE WEYL NON-ABELIAN GAUGE FIELD AND THE THOMAS PRECESSION
Authors: BARBASHOV B. M. , PESTOV A. B.
Published: September 2003

The connection between the Fermi–Walker transport and the Weyl non-Abelian gauge field is established. A theoretical possibility of detecting the Weyl gauge field caused by the Thomas precession of a gyroscope is discussed.
NON-SUSY AND SUSY ONE-STEP UNIFICATION
Authors: PÉREZ-LORENZANA ABDEL , ZEPEDA ARNULFO , PONCE WILLIAM A.
Published: September 2003

We explore the possibility of achieving one-step unification of the standard model coupling constants within non-supersymmetric and supersymmetric gauge models, which at low energies have only the standard particle content. The constraints are the experimental values of αem, αs and sin 2θW at 102 GeV, and the lower bounds for FCNC and proton decay rates. The analysis is done in a model-independent way.
UPDATING OF A $\bar P$ FLUX ESTIMATION VIS-A-VIS THE NEW EXPECTATIONS
Authors: BHATTACHARYYA S. , ROY DHIMAN
Published: September 2003

A new surge of interest is likely to spring up in the near future against the background of speculations on the enhancement of the low-energy antiproton flux from some of the predicted primary antiproton sources owing to the probable occurrence of the rapid fluctuation of the solar modulation in 1999. A previous calculation of antiproton flux based on a specific model of particle production and of a galactic propagation is updated here. The results estimated for moderate solar modulation are in better agreement with both low-energy and high-energy data for [Formula: see text] values by induction of the roles of primary sources of antiprotons and also of some other factors mentioned in this letter.
QUARK–HADRON DUALITY FOR $K^0 - \bar K^0$ MIXING
Authors: PENIN A. A. , PIVOVAROV A. A.
Published: September 2003

A new way of accounting for the long distance contribution to the [Formula: see text] mixing matrix element is described. The sum of hadronic contributions is dual to the standard light quark loop given by the famous box diagram with small perturbative corrections due to strong interactions that are under control. Estimates of nonperturbative QCD corrections are given in the leading order of chiral perturbation theory.
DRINFELD TWIST FOR QUANTUM su(2) IN THE ADJOINT REPRESENTATION
Authors: CHRYSSOMALAKOS CHRYSSOMALIS
Published: September 2003

We give a detailed description of the adjoint representation of Drinfeld's twist element, as well as its coproduct, for su q(2). We also discuss, as applications, the computation of the universal R-matrix in this representation and the problem of symmetrization of identical-particle states with quantum su(2) symmetry.
DISTRIBUTIONAL TORSION OF COSMIC STRINGS WITH POLARIZED SPINNING MATTER
Authors: GARCIA DE ANDRADE L. C.
Published: September 2003

A cosmic string of finite size in Weitzenböck space–time is built where spin polarized particles can be found along the string and orthogonal to it. Only spinning particles polarized along the string contribute to the angular momentum of the string while the other is only a torsion source like in Einstein–Cartan (EC) theory. Cartan torsion is given by a δ-Dirac distribution and the metric is the lift of (2+1)-gravity point particles to (3+1)-cosmic strings.
ELECTRON–POSITRON ANNIHILATION INTO DIRAC MAGNETIC MONOPOLE AND ANTIMONOPOLE: THE STRING AMBIGUITY AND THE DISCRETE SYMMETRIES
Authors: YU. IGNATIEV A. , JOSHI G. C.
Published: September 2003

We address the problem of string arbitrariness in the quantum field theory of Dirac magnetic monopoles. Different prescriptions are shown to yield different physical results. The constraints due to the discrete symmetries (C and P) are derived for the process of electron–positron annihilation into the monopole–antimonopole pair. In the case of the annihilation through the one-photon channel, the production of spin-0 monopoles is absolutely forbidden; spin-1/2 monopole and antimonopole should have the same helicities (or, equivalently, the monopole–antimonopole state should be p-wave 1P1).
SECOND-ORDER CONTRIBUTIONS TO ELASTIC LARGE-ANGLE BHABHA SCATTERING
Authors: ARBUZOV A. B. , KURAEV E. A. , SHAIKHATDENOV B. G.
Published: September 2003

The cross-section of (quasi-)elastic large-angle electron–positron scattering at high energies is calculated. Radiative corrections of the orders [Formula: see text] and [Formula: see text], except pure two-loop box contributions, are explicitly calculated. In the second order we considered the following sources of corrections: (a) virtual photonic corrections coming from squares of one-loop level amplitudes and their relevant interferences (vertex-type and box-type Feynman diagrams); (b) double soft photon emission and one-loop corrections to single soft photon emission. The results are presented analytically.
INTERQUARK POTENTIAL IN SCHRÖDINGER REPRESENTATION
Authors: ZAREMBO K.
Published: September 2003

Static charges are introduced in Yang–Mills theory via coupling to heavy fermions. The states containing static color charges are constructed using integration over gauge transformations. A functional representation for interquark potential is obtained. This representation provides a simple criterion for confinement.
EIGENSTATES OF THE GRAVITATIONAL SCHRÖDINGER EQUATION
Authors: BERNSTEIN DAVID H. , GILADI ELDAR , JONES KINGSLEY R. W.
Published: September 2003

We develop a new algorithm to compute the eigenvalues and eigenfunctions of the gravitational Schrödinger equation. The nonlinear two-point boundary problem is solved by an inner–outer iteration and the resulting method is fast, readily parallelizable, and, unlike shooting methods, is able to compute eigenfunctions with a very large number (>50) of nodes. The theory and implementation of the method are discussed and it is applied to compute the s-wave spectrum of a gravitational Bose–Einstein condensate.
COMPOSITE OPERATOR EFFECTIVE POTENTIAL APPROACH TO QED3
Authors: CAMPBELL-SMITH A.
Published: September 2003

The composite operator effective potential is compared with the conventional Dyson–Schwinger method as a calculational tool for (2+1)-dimensional quantum electro-dynamics. It is found that when the fermion propagator ansatz is put directly into the effective potential, it reproduces exactly the usual gap equations derived in the Dyson–Schwinger approach.
GRAVITATIONAL POTENTIALS AND THE EXISTENCE OF GRAVITATIONAL GREEN'S TENSORS
Authors: DOLAN P. , MURATORI B.
Published: September 2003

The non-local part of the gravitational field Cabcd can be generated by the 16-component Lanczos tensor potential Labc. When six gauge conditions are imposed, Labe;e=0, its ten degrees of freedom match those of the Weyl tensor. The Penrose wave equation for Cabcd can be independently derived from that for Labc. The consistency between Labc and Cabcd is also shown by the compatibility of their algebraic classifications. An unexpected insight into the relationship of Labc and Cabcd is found in "Euclidean gravity" which in turn leads to the introduction of a gravitational Green's tensor [Formula: see text] corresponding to the potential Labc.
NUCLEON INSTABILITY IN A SUPERSYMMETRIC SU(3)c× SU(3)L×U(1) MODEL
Authors: LONG HOANG NGOC , PAL PALASH B.
Published: September 2003

We construct the supersymmetric version of a model based on the gauge group SU(3) c× SU(3) L× U(1) . We discuss the mechanism of baryon number violation which induces nucleon decay, and derive bounds on the relevant couplings. We point out a new mechanism for nucleon decay which can also appear in R-violating MSSM.
FIRST LATTICE EVIDENCE FOR A NONTRIVIAL RENORMALIZATION OF THE HIGGS CONDENSATE
Authors: CEA P. , COSMAI L. , CONSOLI M.
Published: September 2003

General arguments related to "triviality" predict that, in the broken phase of (λΦ4)4 theory, the condensate <Φ> rescales by a factor Zφ different from the conventional wave function renormalization factor, Z prop . Using a lattice simulation in the Ising limit, we measure Zφ= m2χ from the physical mass and susceptibility and Z prop from the residue of the shifted-field propagator. We find that the two Z's differ, with the difference increasing rapidly as the continuum limit is approached. Since Zφ affects the relation of <Φ> to the Fermi constant, it can sizably affect the present bounds on the Higgs mass.
THERMAL FLUCTUATIONS OF DISORIENTED CHIRAL CONDENSATE DOMAINS
Authors: DIGAL SANATAN , SRIVASTAVA AJIT M.
Published: September 2003

We argue that disoriented chiral condensate (DCC) domains are not well defined for temperatures above the Ginzburg temperature T G (≃0.7 T c ). Above T G , the dynamics of DCC domains is dominated by thermal fluctuations leading to fluctuating orientation of the chiral field in a given domain. It implies that disorientation of chiral field, and hence DCC formation may happen even in relatively lower energy collisions where the temperature only reaches T G , and never rises to T c . It also means that detection of DCC cannot be taken as a signal for an intermediate chirally symmetric phase of matter. Using these considerations, we estimate the probability distribution for DCC domains as a function of the chiral angle.
PULSAR VELOCITIES DUE TO VIOLATION OF THE EQUIVALENCE PRINCIPLE BY NEUTRINOS
Authors: HORVAT R.
Published: September 2003

We consider the pulsar velocity problem and relate it to some unconventional neutrino oscillation mechanisms based on the violation of the equivalence principle by neutrinos. We show that the observed pulsar velocities may be explained by violations at the level from 10-9 to 10-10 in the case of a non-universal tensor neutrino-gravity coupling, whereas there is no solution in the case of a non-universal scalar neutrino-gravity coupling. Neutrinos may remain massless and the requisite magnetic field strength is similar to that in the conventional mass oscillation mechanism.
ON OFF-SHELL BOSONIC STRING AMPLITUDES
Authors: CAPPIELLO LUIGI , MAROTTA RAFFAELE , PETTORINO ROBERTO , PEZZELLA FRANCO
Published: September 2003

We give a simple prescription for computing, in the framework of the bosonic string theory, off-shell one-loop amplitudes with any number of external massless particles, for both the open and closed strings. We discuss their properties and, in particular, for the two-string one-loop amplitudes, we show their transversality.
CKM MATRIX ELEMENTS AND MAXIMALITY OF CP-VIOLATION
Authors: GILL P. S. , GUPTA MANMOHAN
Published: September 2003

Maximality of CP-violation is defined by maximizing the Jarlskog rephasing invariant |J| which is twice the area of any of the six unitarity triangles. When the area of two of the unitarity triangles is maximized w.r.t.|Vtd|, we obtain |Vtd|=(8.5-10.2)×10-3 and CP violating phase δ=60°-168°. Two well-known triangles yield J expt =(2.2-3.7)×10-5 which leads to δ = 33°-146° and |Vtd|=(5.6-13.1)×10-3. When the constraints due to "maximality" and J expt are considered simultaneously, we obtain |Vtd|=(8.5-10.2)×10-3 and δ=60°-136°.
ON THE (0, 4) CONFORMAL FIELD THEORY OF THE THROAT
Authors: JOHNSON CLIFFORD V.
Published: September 2003

In SO(32) heterotic string theory, the space–time at the core of N coincident NS five-branes is an infinite throat, ℝ×S3. As shown by Witten, the throat signals a singularity in the usual heterotic string conformal field theory and a nonperturbative USp (2N) gauge group appears, due to the N small instantons at the five-branes' core. Nevertheless, we look for some trace of the nonperturbative physics in the description of the heterotic string infinitely far down the throat. Our guide is a D1-brane probing N D5-branes in type I, which yields a (1+1)-dimensional (0, 4) supersymmetric model with ADHM data in its couplings, as shown by Douglas. The neighborhood of the classical boundary of the hypermultiplet moduli space of the theory flows to an exact conformal field theory description of the throat theory. Ironically, the remnant of the nonperturbative symmetry is indeed found in the conformal field theory, lurking in the structure of the partition function, and encoded in a family of deformations of the theory along flat directions. The deformations have an explicit description using the flow from type I theory, and have a hyper-Kähler structure. Similar results hold true for the analogous (4, 4) supersymmetric situation in type IIB theory, as is evident in the work of Diaconescu and Seiberg.