bluuebunny/crossref_metadata_2025 huggingface dataset:
A RULE OF THUMB DERIVATION OF BORN–INFELD ACTION FOR D-BRANES
Authors: ENDO RIKA , KURIKI RIE , SUGAMOTO AKIO , NOJIRI SHIN'ICHI
Published: September 2003

A rule of thumb derivation of the Dirac–Born–Infeld action for D-branes is studied à la Fradkin and Tseytlin, by simply integrating out of the superstring coordinates in a narrow strip attached to the D-branes. In case of superstrings, the coupling of Ramond–Ramond fields as well as the Dirac–Born–Infeld type coupling of the Neveu Schwarz–Neveu Schwarz fields come out in this way.
COMMENT ON "NON-ABELIAN BOSONIZATION AND HIGHER SPIN SYMMETRIES"
Authors: STOILOVS M. N.
Published: September 2003

The equivalence between the higher spin current algebras in non-Abelian free fermionic and the corresponding WZNW models is established.
ON THE COSMOLOGICAL CONSTANT IN QUANTUM COSMOLOGY OF THE BRANS–DICKE THEORY
Authors: ZHU ZONG-HONG , ZHANG YUAN-ZHONG , WU XIANG-PING
Published: September 2003

We study the issue of the cosmological constant in quantum cosmology combined with the Brans–Dicke gravitational theory. Using the minisuperspace approximation, we build up the Wheeler–De Witt equation and then obtain the wave function of the universe by further assuming the WKB approximation under the boundary condition proposed by Vilenkin. It is shown that the amplitude of the resulting wave function, which represents an expanding universe, reaches its peaks if the cosmological constant vanishes.
AMBIGUITIES IN LOOP QUANTIZATION: AREA VS. ELECTRIC CHARGE
Authors: CORICHI ALEJANDRO , KRASNOV KIRILL V.
Published: September 2003

In this letter we compare the ambiguity that, as pointed out by Immirzi, arises in the loop quantization of general relativity with a somewhat similar ambiguity in the quantization of Maxwell theory. The "loop" quantization leads to a quantum theory in which the fundamental excitations are loop-like rather than particle-like. Each such loop plays the role of a quantized Faraday's flux line. For the case of Maxwell theory, we show that the quantization depends on an arbitrary choice of a parameter ε that carries the dimension of electric charge. For each value of ε the electric charge that can be contained inside a bounded spatial region is automatically quantized in units of ℏ/ε. The requirement of consistency with the quantization of electric charge observed in our Universe fixes a value of the, so far arbitrary, parameter ε of the theory. We compare the ambiguity in the choice of parameter ε with the β-ambiguity of quantum gravity, and comment on the possible way this ambiguity can be fixed.
STATIC COLORED SU(2) SOURCES IN (1+1) DIMENSIONS — AN ANALYTIC SOLUTION IN THE ELECTRIC REPRESENTATION
Authors: PACHOS JIANNIS , TSAPALIS ANTONIOS
Published: September 2003

Within the Schrödinger electric representation, we analytically calculate the complete set of wave functionals obeying Gauss' law with static sources in a general representation of SU(2) in (1+1) dimensions. The effective potential is found to be linear in the distance between the sources with the string tension depending on the polarization of the solution.
CAN GENERAL RELATIVISTIC DESCRIPTION OF GRAVITATION BE CONSIDERED COMPLETE?
Authors: AHLUWALIA D. V.
Published: September 2003

The local galactic cluster, the Great attractor, embeds us in a dimensionless gravitational potential of about -3×10-5. In the solar system, this potential is constant to about 1 part in 1011. Consequently, planetary orbits, which are determined by the gradient in the gravitational potential, remain unaffected. However, this is not so for the recently introduced flavor-oscillation clocks where the new redshift-inducing phases depend on the gravitational potential itself. On these grounds, and by studying the invariance properties of the gravitational phenomenon in the weak fields, we argue that there exists an element of incompleteness in the general relativistic description of gravitation. An incompleteness-establishing inequality is derived and an experiment is outlined to test the thesis presented.
HIDDEN ALGEBRA OF THREE-BODY INTEGRABLE SYSTEMS
Authors: TURBINER ALEXANDER
Published: September 2003

It is shown that all three-body quantal integrable systems that emerge in the Hamiltonian reduction method possess the same hidden algebraic structure. All of them are given by a second degree polynomial in generators of an infinite-dimensional Lie algebra of differential operators.
SCREENING CURRENT REPRESENTATION OF QUANTUM SUPERALGEBRAS
Authors: RASMUSSEN JØRGEN
Published: September 2003

In this letter a screening current or contour representation is given for certain quantum superalgebras. The Gomez–Sierra construction of quantum groups in conformal field theory is generalized to cover superalgebras and illustrated using recent results on screening currents in affine current superalgebra.
ON THE CONSTRUCTION OF GLOBAL MODELS DESCRIBING ROTATING BODIES; UNIQUENESS OF THE EXTERIOR GRAVITATIONAL FIELD
Authors: MARS MARC , SENOVILLA JOSÉ M. M.
Published: September 2003

The problem of constructing global models describing isolated axially symmetric rotating bodies in equilibrium is analyzed. It is claimed that, whenever the global space–time is constructed by giving boundary data on the limiting surface of the body and integrating Einstein's equations on both inside and outside the body, the problem becomes overdetermined. Similarly, when the space–time describing the interior of the body is explicitly given, the problem of finding the exterior vacuum solution becomes overdetermined. We discuss in detail the procedure to be followed in order to construct the exterior vacuum field created by a given but arbitrary distribution of matter. Finally, the uniqueness of the exterior vacuum gravitational field is proven by exploiting the harmonic map formulation of the vacuum equations and the boundary conditions prescribed from the matching.
AN UPPER LIMIT ON MASS DENSITY OF QUARK NUGGETS FROM THE MICROLENSING EVENT STATISTICS
Authors: YOON SEUNG UN , LEE CHUL H. , YANG JONGMANN
Published: September 2003

We calculate the spectrum of separations between nucleation sites of hadron bubbles formed during the first-order cosmic QCD phase transition considered within the Lee–Wick model, an effective QCD model. On the basis of the separation spectrum, we construct a naive model mass spectrum of quark nuggets. Using this mass spectrum and the microlensing event statistics of the MACHO group, we place an upper limit on the mass density of quark nuggets in the galactic halo.
THE GRAVITATIONAL VAVILOV–CHERENKOV EFFECT
Authors: SAA ALBERTO , SCHIFFER MARCELO
Published: September 2003

In this letter we show that an uncharged black hole moving superluminally in a transparent dielectric medium violates Hawking's area theorem. The violation can be overcome through the emission of radiation. Since modes cannot emerge from the black hole itself, this radiation must originate from a collective effect in the medium, in complete analogy with the Vavilov–Cherenkov effect. However, because the black hole is uncharged, the emission mechanism must be different. We discuss the physical origin of the effect and obtain a Newtonian estimation. Then we obtain the appropriate equations in the relativistic case and show that the field which is radiated away is a combination of gravitational and electromagnetic degrees of freedom. Possible astrophysical relevance for the detection of primordial black holes and binary systems is discussed.
THE SINGULARITY IN GENERIC GRAVITATIONAL COLLAPSE IS SPACELIKE, LOCAL AND OSCILLATORY
Authors: BERGER B. K. , GARFINKLE D. , ISENBERG J. , MONCRIEF V. , WEAVER M.
Published: September 2003

A longstanding conjecture by Belinskii, Khalatnikov and Lifshitz that the singularity in generic gravitational collapse is spacelike, local and oscillatory is explored analytically and numerically in spatially inhomogeneous cosmological space–times. With a convenient choice of variables, it can be seen analytically how nonlinear terms in Einstein's equations control the approach to the singularity and cause oscillatory behavior. The analytic picture requires the drastic assumption that each spatial point evolves toward the singularity as an independent spatially homogeneous universe. In every case, detailed numerical simulations of the full Einstein evolution equations support this assumption.
WORMHOLES, GAMMA RAY BURSTS AND THE AMOUNT OF NEGATIVE MASS IN THE UNIVERSE
Authors: TORRES DIEGO F. , ANCHORDOQUI LUIS A. , ROMERO GUSTAVO E.
Published: September 2003

In this letter, we assume that negative mass objects can exist in the extragalactic space and analyze the consequences of their microlensing on light from distant active galactic nuclei. We find that such events have very similar features to some observed gamma ray bursts and use recent satellite data to set an upper bound to the amount of negative mass in the universe.
GRAVITY, COSMOLOGY AND PARTICLE PHYSICS WITHOUT THE COSMOLOGICAL CONSTANT PROBLEM
Authors: GUENDELMAN E. I. , KAGANOVICH A. B.
Published: September 2003

This letter elucidates recent achievements of the "nongravitating vacuum energy (NGVE) theory" which has the feature that a shift of the Lagrangian density by a constant does not affect dynamics. In the first-order formalism, a constraint appears that enforces the vanishing of the cosmological constant Λ. Standard dynamics of gauge unified theories (including fermions) and their SSB appear if a four-index field strength condensate is present. At the vacuum state, there is exact balance (to zero) of the gauge fields condensate and the original scalar fields potential. As a result it is possible to combine the solution of the Λ problem with inflation and transition to a Λ=0 phase without fine tuning after a reheating period. The model opens new possibilities for a solution of the hierarchy problem.
COVARIANT DEFORMATION OF THE POINCARÉ–HEISENBERG ALGEBRA
Authors: HEUSON CLEMENS
Published: September 2003

Starting from deformed coordinates a covariant deformation of the Poincaré and Heisenberg algebra is derived. The deformation function is determined uniquely by the Jacobi identities leading to noncommutative coordinates, a generalized uncertainty principle and deformed Lorentz transformations.
YANGIAN DEFORMATION OF THE LIE ALGEBRA dĩff(T2)
Authors: LIPIŃSKI Z.
Published: September 2003

New solution of a classical Yang–Baxter equation on a loop extended, "modified" Lie algebra of a diffeomorphism group of a torus dĩff(T2)[λ]is given.

Lie bialgebra structure on dĩff(T2)[λ] is defined. By quantization of a defined Lie bialgebra, a Yangian algebra Y(dĩff(T2)) is obtained.

Existence of a quantum double and a quantum R-matrix for Y(dĩff(T2)) is considered.
NEGATIVE ENERGIES AND THE LIMIT OF CLASSICAL SPACE–TIME
Authors: HELFER ADAM D.
Published: September 2003

Relativistic quantum field theories predict negative energy densities, contravening a basic tenet of classical physics and a fundamental hypothesis of the deepest results in classical general relativity. These densities may be sources for exotic general relativistic effects, and may also lead to pathologies.

Combining Ford's "quantum inequality" with quantum restrictions on measuring devices, we present an argument that these densities nevertheless satisfy a sort of "operational" positivity: the energy in a region, plus the energy of an isolated device designed to detect or trap the exotic energy, must be non-negative. This will suppress at least some pathological effects.

If we suppose also that Einstein's field equation holds, then no local observer can measure the geometry of a negative energy density regime accurately enough to infer a negative energy density form the curvature. This means that the physics of a negative energy regime cannot be adequately modeled by a classical space–time.
SINGLE MASSLESS MAJORANA FERMION IN THE DOMAIN-WALL FORMALISM
Authors: HOTTA TOMOHIRO , IZUBUCHI TAKU , NISHIMURA JUN
Published: September 2003

We study the domain-wall formalism with additional Majorana mass term for the unwanted zero-mode, which has recently been proposed for lattice construction of 4D [Formula: see text] super-Yang–Mills theory without fine-tuning. Switching off the gauge field, we study the dispersion relation of the energy eigenstates numerically, and find that the method works for reasonable values of Majorana mass. We point out, however, that when the Majorana mass is too large, a problem arises which can be explained in terms of seesaw mechanism.
SELF-DUAL SOLITONS IN N=2 SUPERSYMMETRIC SEMILOCAL CHERN–SIMONS THEORY
Authors: EDELSTEIN JOSÉ D.
Published: September 2003

We embed the semilocal Chern–Simons–Higgs theory into an N=2 supersymmetric system. We construct the corresponding conserved supercharges and derive the Bogomol'nyi equations of the model from supersymmetry considerations. We shown that these equations hold provided certain conditions on the coupling constants as well as on the Higgs potential of the system, which are a consequence of the huge symmetry of the theory, are satisfied. They admit string-like solutions which break one half of the supersymmetries — BPS Chern–Simons semilocal cosmic strings — whose magnetic flux is concentrated at the center of the vortex. We study such solutions and show that their stability is provided by supersymmetry through the existence of a lower bound for the energy, even though the manifold of the Higgs vacuum does not contain non-contractible loops.
RENORMALIZATION OF FUNCTIONAL SCHRÖDINGER EQUATION BY BACKGROUND FIELD METHOD
Authors: ZAREMBO K.
Published: September 2003

Renormalization group transformations for Schrödinger equation are performed in both φ4 and Yang–Mills theories. The dependence of the ground state wave functional on rapidly oscillating fields is found. For Yang–Mills theory, this dependence restricts a possible form of variational ansatz compatible with asymptotic freedom.
ANALYTICITY AND MINIMALITY OF NONPERTURBATIVE CONTRIBUTIONS IN PERTURBATIVE REGION FOR $\bar \alpha_{{\lc s}}$
Authors: ALEKSEEV ALEKSEY I. , ARBUZOV BORIS A.
Published: September 2003

It is shown that the possibility of freezing a QCD running coupling constant at zero with the approach of "forced analyticity" is not in agreement with Schwinger–Dyson equation for the gluon propagator. We propose to add to the analytic expression the well-known infrared singular term 1/q2 as well as a pole term corresponding to "excited gluon". By this example we formulate the principle of minimality of nonperturbative contributions in perturbative (ultraviolet) region, which allows us to fix ambiguities when introducing nonperturbative terms and maintain the finiteness of the gluon condensate. As a result, we obtain estimates of the gluon codensate, which agree quite well with the existing data. The value of the "excited gluon" mass is also of considerable interest.
ON THE TEMPERATURE-DEPENDENT COUPLING CONSTANT IN THE VECTOR N-COMPONENT (λφ4)D MODEL.
Authors: DE CALAN C. , MALBOUISSON A. P. C. , SVAITER N. F.
Published: September 2003

For the massive (λφ4)D vector N-component model in the large-N limit, we investigate the thermal behavior of the coupling constant. For the Wick-ordered model we check that there is no first-order phase transition induced by the thermal renormalized coupling constant regardless of the dimension D. Moreover, for D=3 we are able to give an exact formula for the temperature behavior of the coupling constant. For the non-Wick-ordered model all the contributions from the thermal part of the tadpoles must be taken into account. We indicate how this may be done in arbitrary dimension D.
INDUCED MAGNETIC MOMENTS IN THREE-DIMENSIONAL GAUGE THEORIES WITH EXTERNAL MAGNETIC FIELDS
Authors: MAVROMATOS NICK E. , MOMEN ARSHAD
Published: September 2003

We study the appearance of induced parity-violating magnetic moment, in the presence of external magnetic fields, for even-number of fermion species coupled to dynamical fields in three dimensions. Specifically, we use an SU(2) × U(1) gauge model for dynamical gauge symmetry breaking, which has also been proposed recently as a field theoretical model for high-Tc superconductors. By decomposing the fermionic degrees of freedom in terms of Landau levels, we show that, in the effective theory with the lowest Landau levels, a parity-violating magnetic moment interaction is induced by the higher Landau levels when the fermions are massive. The possible relevance of this result for a recently observed phenomenon in high-T c superconductors is also discussed.
SUPERCONFORMAL FIELD THEORY WITH BOUNDARY: FERMIONIC MODEL
Authors: APIKYAN S. A. , SAHAKYAN D. A.
Published: September 2003

Fermionic model of superconformal field theory with boundary is considered. The "boundary" Ward identity for this theory is written and the boundary states for fermionic and spin models are constructed. For this model, the "bootstrap" equations for boundary structure constants are derived.
ON MIXING ANGLES AND MAGNETIC MOMENT OF HEAVY TAU NEUTRINO
Authors: GNINENKO S. N.
Published: September 2003

If the magnetic moment of unstable tau neutrinos with the mass of 0(MeV) is in the region of 10-8μB≲ μντ≲ 10-6μB, it is compatible with the present experimental and cosmological bounds.

We point out that if the tau neutrino has such a large magnetic moment and can oscillate into a neutrino of another flavor, the results from νe scattering experiment at LAMPF constrain the tau neutrino mixing angles to sin 2 2θeτ≲ 2 × 10-6-2 × 10-2 and sin 2 2θμτ ≲ 10-6-10-2 depending on the magnetic moment value in the allowed region.
ON THE SUPERPOSITION OF THE RELATIVE PARA-BOSE AND PARA-FERMI SETS
Authors: REMEZO L.
Published: September 2003

We study the relation between Mostafazadeh's approach on a superposition of para-bosons and parafermions of the same order p= 2 and the superposition of the two well-known relative sets. Then, a simultaneous study of the operators belonging to these different relative sets is allowed in the same superstrucuture. As the above considerations lead to explicitly time-independent operators only, we also put in evidence the superalgebra sl (2/2;ℜ) associated with the general case when all the operators of the two relative sets are included.
SUPER FIVE-BRANES IN D=10, N=1 SUPER-YANG–MILLS THEORY
Authors: GOTOH YOSHINORI , OKOUCHI IKUO
Published: September 2003

In D=10, N=1 super-Yang–Mills theory we give the background breaking a half of supersymmetry. In the background there is a six-dimensional object, the so-called D=10 five-brane.
THE OCTET OF GOLDSTONE-BOSONS IN THE SU(3) LINEAR σ-MODEL IN THE QRPA
Authors: AOUISSAT Z. , BOHR O. , WAMBACH J.
Published: September 2003

A symmetry conserving, nonperturbative treatment based on a variational squeezed vacuum state in conjunction with a well-defined class of RPA fluctuations is applied to the SU(3) linear σ-model. It is shown that the Goldstone theorem holds exactly both at zero and finite temperatures. The approach represents a systematic procedure which avoids problems of the Gaussian functional with the symmetries.
SCALAR SECTOR OF THE 3 3 1 MODEL WITH THREE HIGGS TRIPLETS
Authors: LONG HOANG NGOC
Published: September 2003

A scalar sector of the 3 3 1 model with three Higgs triplets is considered in detail. The mass spectrum, eigenstates and interactions of the Higgs and the SM gauge bosons are derived. We show that one of the neutral scalars can be identified with the standard model Higgs boson, and in the considered potential, there is no mixing between scalars having vev and those without vev.
CHAOS AND A RESONANCE MECHANISM FOR STRUCTURE FORMATION IN INFLATIONARY MODELS
Authors: DE OLIVEIRA H. P. , DAMIÃO SOARES I.
Published: September 2003

We exhibit a resonance mechanism of amplification of density perturbations in inflationary models, using a minimal set of ingredients (an effective cosmological constant, a scalar field minimally coupled to the gravitational field and matter), common to most models in the literature of inflation. This mechanism is based on the structure of homoclinic cylinders, emanating from an unstable periodic orbit in the neighborhood of a saddle-center critical point, present in the phase space of the model. The cylindrical structure induces oscillatory motions of the scales of the universe whenever the orbit visits the neighborhood of the saddle-center, before the universe enters a period of exponential expansion. The oscillations of the scale functions produce, by a resonance mechanism, the amplification of a selected wave number spectrum of density perturbations, and can be used to explain the hierarchy of scales observed in the actual universe. The transversal crossings of the homoclinic cylinders induce chaos in the dynamics of the model — a fact closely connected to the resonance mechanism occuring immediately before the exit to inflation.
AXION DECAY OF A PHOTON IN AN EXTERNAL ELECTROMAGNETIC FIELD
Authors: MIKHEEV N. V. , YA. PARKHOMENKO A. , VASSILEVSKAYA L. A.
Published: September 2003

An interaction of a pseudoscalar particle with two photons induced by an external electromagnetic field is used to study the photon decay γ→γa where a is a pseudoscalar particle associated with the Peccei–Quinn U(1) symmetry. The field-induced axion emission by photon is analyzed as a possible source of energy losses by astrophysical objects.
TIME-OF-NIGHT VARIATION OF SOLAR NEUTRINOS
Authors: NARAYAN MOHAN , RAJASEKARAN G. , SINHA RAHUL
Published: September 2003

We investigate the time-of-night variation of solar neutrino rate which will be of relevance to super-Kamioka and Sudbury neutrino detectors in the framework of oscillations among the three flavors. An analytical method of computing the regeneration in the earth is presented. If day–night effect is seen, we show how the study of the time-of-night variation will allow the determination of the neutrino parameters.
NON-EXISTENCE OF LOCAL INTEGRALS OF MOTION IN THE MULTI-DEFORMED ISING MODEL
Authors: FONSECA PEDRO D.
Published: September 2003

We confirm the non-integrability of the multi-deformed Ising model — an already expected result. After deforming with the energy operator ϕ1,3, we use the Majorana free fermionic representation for the massive theory to show that, besides the trivial one, no local integrals of motion can be built in the theory arising from perturbing with both energy and spin operators.
INDICATIONS FOR AN ANOMALOUS RIGHT-HANDED COUPLING OF THE b-QUARK FROM A MODEL-INDEPENDENT ANALYSIS OF LEP AND SLD DATA ON Z DECAYS
Authors: FIELD J. H.
Published: September 2003

A model-independent analysis is made using the LEP and SLD data on Z decays available at the end of 1996. The effective weak coupling constants of leptons, c quarks and b quarks are extracted. Except for the right-handed b-quark coupling, they all agree with the predictions of the standard electroweak model for mt=180 GeV and mH=100 GeV. The right-handed b-quark coupling is found to be 42% and 3.2 standard deviations above the standard model prediction.
ON TOPOLOGICAL SUSCEPTIBILITY, VACUUM ENERGY AND THETA DEPENDENCE IN GLUODYNAMICS
Authors: HALPERIN IGOR , ZHITNITSKY ARIEL
Published: September 2003

We suggest that the topological susceptibility in gluodynamics can be found in terms of the gluon condensate using renormalizability and heavy fermion representation of the anomaly. Analogous relations can also be obtained for other zero-momentum correlation functions involving the topological density operator. Using these relations, we find the θ dependence of the condensates , [Formula: see text] and of the partition function for small θ and an arbitrary number of colors.
ESTIMATION OF $\bar p/p$ FLUX RATIO FROM LEAKY BOX AND CLOSED GALAXY MODELS USING CERN ACCELERATOR RESULTS ON $\bar p$ PRODUCTION
Authors: SAHA R. K. , MAJUMDAR R. , PAL P. , BHATTACHARYYA D. P.
Published: September 2003

Using steady state leaky box and closed galaxy models and the latest primary proton spectrum based on the directly measured data along with the accelerator data on [Formula: see text] production, the [Formula: see text] flux ratio in the interstellar medium has been estimated in the spectral range from 6 to 100 GeV/n. The derived result is in approximate agreement with the balloon borne calorimeter data of Golden et al.

We have closed galaxy model for the estimation of the old component and young component of primary proton spectrum from the composite primary proton spectrum obtained from the recent experiments performed by Menn et al., Webber et al., Seo et al., JACEE and others. The derived results differ slightly from the results of Protheroe, Pal and Bhattacharyya.
THE BAR INSTABILITY REVISITED IN COSMOLOGICAL SCENARIO
Authors: CURIR ANNA
Published: September 2003

About two-thirds of spiral galaxies are classified as barred: only one-third is very strongly barred (SB) and the other is classified as "intermediate" SB galaxies, i.e. galaxies with a faint bar. Bars are quasi-stationary density waves originated by swing amplification mechanisms. We use smooth-particle-hydrodynamical simulations to give insights into the role triaxiality of the halo on triggering the bar instability and to investigate how tidal interactions act on the bar evolution. We argue that the triaxiality of the primordial halo and the weight of the halo have a fundamental role in monitoring the incidence of the bar instability in spiral galaxies.
ON THE STABILITY OF WORMHOLES IN WEITZENBÖCK SPACE–TIME
Authors: GARCIA DE ANDRADE L. C.
Published: September 2003

The pseudo-Riemannian Lorentzian wormholes are extended to Weitzenböck T4 teleparallel space–times. Non-static wormholes are shown to possess a Cartan torsion which influences the shape of the wormhole. In the static, all components of the torsion form are shown to vanish at the wormhole throat. At infinite time, coordinate torsion seems to be stable in the sense that not all components of torsion vanish. When the wormhole is sealed off torsion just one component of torsion remains finite while the others diverge yielding a torsion singularity.
FERMION MASSES AND MIXING IN 331 MODELS WITH HORIZONTAL SYMMETRY
Authors: TULLY M. B. , JOSHI G. C.
Published: September 2003

The possibility of adding an SU(2) horizontal symmetry to the 331 model is studied. It is found that simple, anomaly-free fermion assignments can be made which lead to plausible results for fermion masses and mixings. In particular, all particles of the first generation are massless at tree-level, and the CKM matrix acquires a realistic form.
COMMENTS ON THE GEOMETRY OF THE CONICAL SPACE–TIME
Authors: TAVARES D. M. , ROMERO C.
Published: September 2003

We consider the conical space–time generated by a cosmic string and compute its Riemannian curvature by analyzing the geometry of a foliation t= const , z= const . We show that the problem is then reduced to the calculation of the Gaussian curvature K of a bidimensional cone. Through two simple geometrical examples we give a prescription for obtaining K.
THE HAGEDORN TRANSITION AND THE MATRIX MODEL FOR STRINGS
Authors: SATHIAPALAN B.
Published: September 2003

We use the matrix formalism to investigate what happens to strings above the Hagedorn temperature. We show that is not a limiting temperature but a temperature at which the continuum string picture breaks down. We study a collection of N D-0-branes arranged to form a string having N units of light-cone momentum. We find that at high temperatures the favored phase is one where the string worldsheet has disappeared and the low-energy degrees of freedom consists of N2 massless particles ("gluons"). The nature of the transition is very similar to the deconfinement transition in large-N Yang–Mills theories.
THE TRANSVERSAL SUBMANIFOLDS AND GAUSS–BONNET–CHERN THEOREM
Authors: YANG GUO-HONG
Published: September 2003

From general ϕ-mapping method and transverse theory, the Gauss–Bonnet–Chern theorem is discussed in detail. Through the calculation of the generalized Winding number, i.e. the degree of Gauss map, the Euler–Poincaré characteristic is decomposed in terms of two transversal submanifolds. This decomposition is a further detailed study of Gauss–Bonnet–Chern theorem and Poincaré–Hopf index theorem.
NUMERICAL SIMULATION OF RANDOM PATHS WITH A CURVATURE-DEPENDENT ACTION
Authors: BAIG M. , CLUA J. , JARAMILLO A.
Published: September 2003

We study an ensemble of closed random paths, embedded in ℝ3, with a curvature-dependent action. Previous analytical results indicate that there is no crumpling transition for any finite value of the curvature coupling. Nevertheless, in a high statistics numerical simulation, we observe two different regimes for the specific heat separated by a rather smooth structure. The analysis of this fact warns us about the difficulties in the interpretation of numerical results obtained in cases where theoretical results are absent and a high statistics simulation is unreachable. This may be the case of random surfaces.
ON THE PHYSICAL ORIGIN OF THE OPPENHEIMER–AHLUWALIA ZERO-ENERGY SOLUTIONS OF MAXWELL EQUATIONS
Authors: CHUBYKALO ANDREW E.
Published: September 2003

By virtue of the Chubykalo–Smirnov–Rueda generalized form of the Maxwell–Lorentz equation, a new form of the energy density of the electromagnetic field is obtained. This result allows us to explain a physical origin of the Oppenheimer–Ahluwalia zero-energy solutions of the Maxwell equations.
REPRESENTATIONS AND BPS STATES OF 10+2 SUPERALGEBRA
Authors: MANVELYAN R. , MELIKYAN A. , MKRTCHYAN R.
Published: September 2003

The 12-D supersymmetry algebra is considered, and classification of BPS states for some canonical form of second-rank central charge is given. It is shown that possible fractions of survived supersymmetry can be 1/16, 1/8, 3/16, 1/4, 5/16 and 1/2, the values 3/8, 7/16 cannot be achieved in this way. The consideration of a special case of nonzero sixth-rank tensor charge is also included.
FIELD-THEORETIC REALIZATION OF HEAVY MESONS AS COMPOSITE PARTICLES
Authors: CHEUNG CHI-YEE , ZHANG WEI-MIN
Published: September 2003

We construct a covariant field-theoretic model for the structure of a heavy meson in the heavy quark limit. This model overcomes the limitations caused by non-covariance in the light-front quark model, thus it is very useful for studying hadronic matrix elements at arbitrary momentum transfers. Furthermore, the model satisfies heavy quark symmetry and provides a suitable framework for the systematic evaluation of heavy quark symmetry breaking effects caused by 1/mQ corrections in the heavy quark effective theory of QCD. The Isgur–Wise function, the decay constant, and the axial-vector coupling constant are calculated, and physically realistic results are obtained.
MULTIDIMENSIONAL GEOMETRICAL MODEL OF THE RENORMALIZED ELECTRICAL CHARGE WITH SPLITTING OFF THE EXTRA COORDINATES
Authors: DZHUNUSHALIEV V. D.
Published: September 2003

A geometrical model of electric charge is proposed. This model has "naked" charge screened with a "fur-coat" consisting of virtual wormholes. The 5-D wormhole solution in the Kaluza–Klein theory is the "naked" charge. The splitting off of the 5-D happens on the two spheres (null surfaces) bonding this 5-D wormhole. This allows one to sew two Reissner–Nordström black holes onto it on both sides. The virtual wormholes entrap a part of the electrical flux lines coming into the "naked" charge. This effect essentially changes the charge visible at infinity so that it satisfies the real relation m2<e2.
QUANTUM GRAVITY OF A BRANE-LIKE UNIVERSE
Authors: DAVIDSON AHARON , KARASIK DAVID
Published: September 2003

Quantum gravity of a brane-like Universe is formulated, and its Einstein limit is approached. Regge–Teitelboim embedding of Arnowitt–Deser–Misner formalism, parametrized by the coordinates yA(t,xi), is governed by some ρAB(y,y′,y″). Invoking a novel Lagrange multiplier λ, accompanying the lapse function N and the shift vector Ni, we derive the quadratic Hamiltonian [Formula: see text] The inclusion of mattter resembles minimal coupling. Setting PA=-i(δ/δyA), we derive a bifurcated Wheeler–Dewitt-like equation. Einstein gravity, associated with λ being a certain fourfold degenerate eigenvalue of ρAB, is characterized by a vanishing center-of-mass momentum ∫PAd3x=0. Troublesome (ρ-λI)-1 is then replaced by regular M-1, such that M-1(ρ-λI) defines a projection operator, modifying the Hamiltonian accordingly.
CURRENT ALGEBRA IN THE PATH INTEGRAL FRAMEWORK
Authors: CÁRDENAS V. , LEPE S. , SAAVEDRA J.
Published: September 2003

In this letter we describe an approach to the current algebra based on the path integral formalism. We use this method for Abelian and non-Abelian quantum field theories in (1+1) and (2+1) dimensions and the correct expressions are obtained. Our results show the independence of the regularization of the current algebras.
MASS EFFECTS IN THE QUARK–GLUON DECAYS OF HEAVY PARAQUARKONIA
Authors: PARKHOMENKO A. YA. , SMIRNOV A. D.
Published: September 2003

Quark–gluon decays of heavy paraquarkonia [Formula: see text] are investigated with account of the masses of final quarks. The decay widths and the energy distributions of the final quarks and gluons are calculated in dependence on the relative quark masses. The strong collinear enhancement of the gluon energy distribution at the end of the spectrum is shown to take place in all such decays of ηc and ηb mesons except the decay [Formula: see text]. The total decay width is shown to have an essential dependence on the final quark masses. The corresponding branching ratios of ηc and ηb mesons are numerically estimated with a good agreement of [Formula: see text] with experimental data on ηc decays.
REGULARIZATION AMBIGUITY PROBLEM FOR THE CHERN–SIMONS SHIFT
Authors: NITTOH KOH-ICHI , EBIHARA TORU
Published: September 2003

We consider the Chern–Simons parameter shift with the hybrid regularization consisting of the higher covariant derivative (HCD) and the Pauli–Villars (PV) regulators. We show that the shift is closely related to the parity of the regulators and get the shift and no-shift results by a suitable choice of the PV regulators. A naive treatment of the HCD term leads to incorrect value of the shift.
ACCURATE COSMOLOGICAL PARAMETERS AND SUPERSYMMETRIC PARTICLE PROPERTIES
Authors: NATH PRAN , ARNOWITT R.
Published: September 2003

Future satellite, balloon and ground based experiments will give precision determinations of the basic cosmological parameters and hence determine the amount of cold dark matter in the universe accurately. We consider here two cosmological models, the νCDM model and the ΛCDM model, and examine within the framework of supergravity grand unification the effect this will have for these models on supersymmetry searches at accelerators. In the former example, the gluino (neutralino) mass has an upper bound of about 720(100) GeV and gaps (forbidden regions) may develop at lower energies. In the latter case the upper bound occurs at gluino (neutralino) mass of about 520(70) GeV with the squarks and selectron becoming light when gluino (neutralino) masses are greater than 420(55) GeV. Both models are sensitive to non-universal soft breaking masses, and show a correlation between large (small) dark matter detector event rates and low (high) b→ s + γ branching ratio.
ON RECONCILING ATMOSPHERIC, LSND, AND SOLAR NEUTRINO-OSCILLATION DATA
Authors: AHLUWALIA D. V.
Published: September 2003

The L/E-flatness of the e-like events observed in the recent atmospheric-neutrino data from super-Kamiokande (SuperK) is interpreted to reflect a new symmetry of the neutrino-oscillation mixing matrix. From that we obtain an analytical set of constraints yielding a class of mixing matrices of the property to simultaneously fit both the SuperK and the LSND data. The resulting mass squared difference relevant for the LSND experiment is found as 0.3 eV2. The discussed symmetry, e.g., carries the nature that expectation values of masses for νμ and ντ are identical. These considerations are purely data dictated. A different framework is then applied to the solar neutrino problem. It is argued that a single sterile neutrino is an unlikely candidate to accommodate the data from the four solar neutrino experiments. A scenario is discussed which violates CPT symmetry, and favors the [Formula: see text] system to belong to the "self"–"anti-self" charge conjugate construct in the (1/2, 0)⊕(0,1/2) representation space, where the needed helicity flipping amplitudes are preferred, rather than the usual Dirac, or Majorana, constructs. In the presented framework the emerging SuperK data on solar neutrino flux is reconciled with the Homestake, GALLEX, and SAGE experiments. This happens because the former detects not only the solar νe but also, at a lower cross-section, the oscillated solar [Formula: see text]; while the latter are sensitive only to the oscillation-diminished solar νe flux. A direct observation of solar [Formula: see text] by SNO will confirm our scenario. Finally, we consider the possibility for flavor-dependent gravitational couplings of neutrinos as emerging out of the noncommutativity of the quantum operators associated with the measurements of energy and flavor.
Λb→ΛcP(V) NONLEPTONIC WEAK DECAYS
Authors: GUO X.-H.
Published: September 2003

The two-body nonleptonic weak decays of Λb→ΛcP(V) (P and V represent pseudoscalar and vector mesons respectively) are analyzed in two models: Bethe–Salpeter (BS) model and hadronic wave function model. The calculations are carried out in the factorization approach. The obtained results are compared with other models' calculations.
CONSTRAINTS OF MIXING ANGLES FROM NEUTRINO OSCILLATION EXPERIMENTS AND NEUTRINOLESS DOUBLE BETA DECAY
Authors: FUKUYAMA TAKESHI , MATSUDA KOUICHI , NISHIURA HIROYUKI
Published: September 2003

From the analyses of the recent data of neutrino oscillation experiments (especially the CHOOZ and the super-Kamiokande experiments), we discuss how these data affect the neutrinoless double beta decay ((ββ)0ν) rate and vice versa assuming that neutrinos are Majorana particles. For the case of m1~m2≪m3 (mi are neutrino masses), we obtain, from the data of the CHOOZ and super-Kamiokande, 0.28 ≲ sin 2θ23≲ 0.76 and sin 2θ13≲ 0.05. Combining the latter constraint with the analysis of the "averaged" neutrino mass  appeared in (ββ)0ν, we find that [Formula: see text], which leads to the constraint on  as  ≲ 0.05m3 + (1 - 0.05)m2. For the case of m1≪m2~ m3, we find that the data of neutrino oscillation experiments and (ββ)0ν imply the following constraints of mixing angles: if 0.95m3≲  < m3, [Formula: see text]. If  ≲ 0.95m3, [Formula: see text] and [Formula: see text].
PRIMORDIAL BLACK HOLE PAIR CREATION IN R2 THEORY
Authors: PAUL B. C. , MUKHERJEE S. , SINGH G. P. , BEESHAM A.
Published: September 2003

The probability for quantum creation of an inflationary universe with a pair of black holes has been studied in semiclassical approximation with Hartle–Hawking boundary conditions, assuming a gravitational action which includes a quadratic term in the scalar curvature αR2, α being a constant. The action of the instanton responsible for creating such a universe, with a spatial section with S1×S2 topology, is seen to be less than that of a de Sitter S3 instanton, unless α<-1/(8Λ), where Λ is the cosmological constant. Since negative α implies a classical instability, the probability for production of primordial black holes seems to be suppressd in R2-theory.
NEUTRON–ANTINEUTRON OSCILLATIONS IN NUCLEI REVISITED
Authors: HÜFNER JÖRG , KOPELIOVICH BORIS Z.
Published: September 2003

An upper limit on [Formula: see text] oscillations can be obtained from the stability of matter. This relation has been worked out theoretically and together with data yields [Formula: see text] s. A recent publication claims a different relation and finds a nuclear suppression of the [Formula: see text] oscillations which is two orders of magnitude weaker than the previous evaluations. Using the same approach we find, nevertheless, that the earlier estimates are correct and conclude that future experiments with free neutrons from reactors are capable of putting a stronger limit on the [Formula: see text] oscillation time than experiments with large amount of neutrons bound in nuclei.
BOSONIZATION TO ORDER 1/m BY DUALITY IN THREE DIMENSIONS
Authors: FENG SZE-SHIANG , WANG BIN , QIU XI-JUN , ZONG HONG-SHI
Published: September 2003

The recently discovered bosonization via duality transform can be used in arbitrary space–time dimensions. It is stressed that because of the gauge invariance of the resulting bosonic model for D ≥ 3, the generating functional is not well-defined. This weakness can be eliminated by decomposing the bosonic field into transverse and longitudinal parts and only the transverse part is relevant. In this way the massive Thirring model in (2 + 1) dimensions is bosonized. It is found that the current–current coupling bosonizes into a Maxwell term.
TAMING THE NON-ABELIAN BORN–INFELD ACTION
Authors: YA. AREF'EVA IRINA , FERRETTI GABRIELE , KOSHELEV ALEXEY S.
Published: September 2003

We show how to reduce the non-Abelian Born–Infeld action describing the interaction of two D-particles to the sum of elliptic integrals depending on simple kinematic invariants. This representation gives explicitly all α′ corrections to D-particle dynamics. The α′ corrections induce a stabilization of the classical trajectories such as the "eikonal" which are unstable within the Yang–Mills approximation.
ON THE SCHILD ACTION FOR D=0 AND D=1 STRINGS
Authors: SOLOVIEV OLEG A.
Published: September 2003

It is shown that the integration measure over the matrix Y in the matrix representation of the Schild action can be fixed by comparing the Schild matrix model with the random lattice string model for D=0. It is further checked that the given measure is consistent with the case D= 1 as well.
A UNIFIED COMPOSITE MODEL OF QUARK–LEPTON COLOR INTERACTIONS
Authors: TERAZAWA HIDEZUMI
Published: September 2003

A unified composite model of quark–lepton SU(4) c color interactions in which 15 gauge bosons including a color-octet of gluons, a color-triplet of leptoquarks and their antiparticles, and a "B–L gluon" are made of a subquark and an antisubquark carrying the quark–lepton color quantum number is proposed. The SU(4) c symmetry is spontaneously broken down to SU(3) c due to the condensation of subquark–antisubquark pairs and the B–L gluon becomes [Formula: see text] times heavier than the leptoquarks.
TORSION ON HYPERBOLIC MANIFOLDS AND THE SEMICLASSICAL LIMIT FOR CHERN–SIMONS THEORY
Authors: BYTSENKO A. A. , GONÇALVES A. E. , DA CRUZ W.
Published: September 2003

The invariant integration method for Chern–Simons theory of gauge group SU(2) and manifold Γ\H3 is verified in the semiclassical limit. The semiclassical approximation for the partition function associated with a connected sum of hyperbolic three-manifolds is presented. We discuss briefly L2-analytical and topological torsions of a manifold with boundary.
QUANTUM GRAVITY WITHOUT GHOSTS
Authors: DEWITT BRYCE , MOLINA-PARÍS C.
Published: September 2003

We give an outline of a recently discovered technique for building quantum effective action that is completely independent of gauge-fixing choices and ghost determinants. One makes maximum use of the geometry and fiber bundle structure of the space of field histories and introduces a set of nonlocal composite fields: the geodesic normal fields based on Vilkovisky's connection on the space of histories. The closed-time-path formalism of Schwinger, Bakshi, Mahantappa et al. can be adapted for these fields, and a set of gauge-fixing-independent dynamical equations for their expectation values (starting from given initial conditions) can be computed. An obvious application for such equations is to the study of the formation and radiative decay of black holes, and to other back-reaction problems.
CHAOS–ORDER TRANSITION IN MATRIX THEORY
Authors: YA. AREF'EVA I. , KOSHELEV A. S. , MEDVEDEV P. B.
Published: September 2003

Classical dynamics in SU(2) matrix theory is investigated. A classical chaos–order transition is found. For small enough angular momentum (even for small coupling constant), the system exhibits a chaotic behavior, for large enough angular momentum, the system is regular.
ASYMPTOTIC FREEDOM IN A SCALAR FIELD THEORY ON THE LATTICE
Authors: LANGFELD KURT , REINHARDT HUGO
Published: September 2003

A scalar field theory in four space–time dimensions is proposed, which embodies a scalar condensate, but is free of the conceptual problems of standard ϕ4-theory. We propose an N-component, O(N)-symmetric scalar field theory, which is originally defined on the lattice. The scalar lattice model is analytically solved in the large-N limit. The continuum limit is approached via an asymptotically free scaling. The renormalized theory evades triviality, and furthermore gives rise to a dynamically formed mass of the scalar particle. The model might serve as an alternative to the Higgs sector of the standard model, where the quantum level of the standard ϕ4-theory contradicts phenomenology due to triviality.
OPEN RIGID STRING WITH GAUSS–BONNET TERM IN THE ACTION
Authors: NESTERENKO V. V. , PIROZHENKO I. G.
Published: September 2003

The effect of the Gaussian curvature in the rigid string action on the interquark potential is investigated. The linearized equations of motion and boundary conditions, following from the modified string action, are obtained. The equation which defines the eigen-frequency spectrum of the string oscillations is derived. On this basis the interquark potential generated by the string is calculated in one-loop approximation. A substantial influence of the topological term in the string action on the interquark potential at the distances of order of hadronic size or less is revealed.
THE MINIMAL SUPERSYMMETRIC STANDARD MODEL AND PRECISION OF W-BOSON MASS AND TOP QUARK MASS
Authors: KANG KYUNGSIK , KANG SIN KYU
Published: September 2003

We argue that the present value and accuracy of MW and mt measurements tend to favor the MSSM, provided that the central values of MW and mt stay at the current values, over the SM. By speculating that a precision of order 40 MeV and 3 GeV respectively for MW and mt will be achieved at LEP2 and Tevatron, we show that the prospect for the MSSM will be further enhanced as long as the central values of MW and mt do not increase below the present values. In addition, we discuss how this scenario can constrain the Higgs boson mass and distinguish the Higgs boson of the MSSM type from that of the SM.
BILEPTONS FROM MUON COLLIDER BACKWARD SCATTERING
Authors: FRAMPTON PAUL H. , GUAN XIAOHU
Published: September 2003

There are serious discussions for building a muon collider with μ+μ- collisions at c.o.m. energies up to 4 TeV. We point out that the bileptonic gauge bosons predicted in some extensions of the standard model would be readily discernable from the backward scattering cross-section, for bilepton masses up to a substantial fraction of the c.o.m. energy.
THE RUNNING COUPLING METHOD WITH NEXT-TO-LEADING ORDER ACCURACY AND PION, KAON ELM FORM FACTORS
Authors: AGAEV SHAHIN S.
Published: September 2003

The pion and kaon electromagnetic form factors FM(Q2) are calculated at the leading order of pQCD using the running coupling constant method. In calculations, the leading and next-to-leading order terms in αS((1-x)(1-y)Q2) expansion in terms of αS(Q2) are taken into account. The resummed expression for FM(Q2) is found. Results of numerical calculations for the pion (asymptotic distribution amplitude) are presented.
LAGRANGIAN APPROACH OF THE FIRST-CLASS CONSTRAINED SYSTEMS
Authors: KIM YONG-WAN , PARK YOUNG-JAI , KIM SEUNG-KOOK
Published: September 2003

We show how to systematically derive the exact form of local symmetries for the Abelian Proca and CS models, which are converted into first-class constrained systems by the BFT formalism, in the Lagrangian formalism. As a result, without resorting to a Hamiltonian formulation we obtain the well-known U(1) symmetry for the gauge-invariant Proca model, while showing that for the CS model there exist novel symmetries as well as the usual symmetry transformations.