bluuebunny/crossref_metadata_2025 huggingface dataset:
COMPARISON OF PARTON DISTRIBUTIONS AND STRUCTURE FUNCTIONS FOR THE PROTON
Authors: ABRAMOWICZ H. , CHARCHULA K. , KRAWCZYK M. , LEVY A.
Published: November 2004

A comparative study of the most popular parton parametrizations is presented. The individual parton distributions as well as the F2 structure function are discussed with a particular emphasis on the low x region, 10−4<x<10−2. The predictions of these parametrizations for the F2 structure function have a wide spread which persists also in the HERA kinematical region.
DIPOLE GLUON PROPAGATOR AND QUARKONIUM SPECTROSCOPY
Authors: CHIKOVANI Z.E. , JENKOVSZKY L.L. , PACCANONI F.
Published: November 2004

By using a model for the non-perturbative gluon propagator, suggested by analyticity, we determine the heavy quark potential and calculate the mass spectrum of the [Formula: see text] and [Formula: see text] systems. The same model reproduces the results of lattice calculations for the gluon condensate.
ON THE SHORT DISTANCE BEHAVIOR OF STRING THEORIES
Authors: GUIDA R. , KONISHI K. , PROVERO P.
Published: November 2004

Short distance behavior of string theories is investigated by the use of the discretized path-integral formulation. In particular, the minimum physical length and the generalized uncertainty relation are re-derived from a set of Ward–Takahashi identities. Several issues related to the form of the generalized uncertainty relation and to its implications are discussed. A consistent qualitative picture of short distance behavior of string theory seems to emerge from such a study.
ON THE QUANTUM GROUP STRUCTURE IN WZW MODELS AND CHERN–SIMONS THEORIES
Authors: SIOPSIS GEORGE
Published: November 2004

We discuss the origin of quantum group features in both Wess–Zumino–Witten models and (2 + 1)-dimensional topological Chern–Simons theories. We identify certain matrices in these theories whose elements obey commutation relations characteristic of a quantum group.
HEAVY AXION ON SARK BRIDGE BETWEEN HIGGS AND TECHNICOLOR MODELS
Authors: FRAMPTON P. H. , YANAGIDA T.
Published: November 2004

It is shown how imposition of Peccei–Quinn symmetry leads to a heavy axion and strong constraints in the sark model. The axion and sark masses are derived. Analysis of chiral symmetry breaking leads to mass formulae for pseudo-Goldstone bosons; the lightest is between 44 and 125 GeV. A general picture which bridges between the sark model and a technicolor model, in terms of a new angle, is proposed.
DYNAMICAL EFFECT OF QUANTUM HAIR
Authors: COLEMAN SIDNEY , PRESKILL JOHN , WILCZEK FRANK
Published: November 2004

We show that quantum hair can alter the relation between the temperature and the mass of a black hole. A ZN electric charge on a black hole generates an electric field that is non-perturbative in ħ. A ZN magnetic charge on a black hole can be described classically, and can support a stable remnant. For global quantum hair, in contrast to gauge hair, we find no dynamical effects.
A LOWER BOUND ON THE HIGGS BOSON AND TOP QUARK MASSES FROM A CONSTRAINT ON THE Φ4 COUPLING
Authors: MAHAJAN S. , MUKHERJEE A. , PANCHAPAKESAN N. , SAXENA R. P. , SETHI S. K.
Published: November 2004

It is pointed out that by imposing the requirement of non-negativity on the running ϕ4 coupling λ(t) in the standard electroweak model, lower bounds on the masses of the Higgs boson and the top quark can be obtained. If m H ≳ 25 GeV , the bound corresponds to mt ≳ 45 GeV . More useful bounds can be derived in a temperature-dependent theory.
DUALITY AND DILATON
Authors: TSEYTLIN A. A.
Published: November 2004

We review and elaborate on the issue of the dilaton transformation under the usual r → α′/r target space duality and its "non-static" generalization (or σ-model duality). It is found that the transformation law r → α′/r, [Formula: see text] which guarantees duality at the one-loop σ-model level should be modified at two (and higher) loop order. The "non-static" duality is illustrated on the example of "cosmological" solutions in D ≥ 2 with time-dependent radii of space torus.
QUANTUM ACTION PRINCIPLE AND SCHRÖDINGER PHASES
Authors: KURATSUJI HIROSHI
Published: November 2004

The action principle in quantum mechanics is examined from a novel point of view with specifical emphasis on phase functions. The generalized transition amplitude can be expressed by exponentiation of the quantum action which is called Schrödinger's phase. Physically speaking, the Schrödinger phase represents a measure of "quantum inaccuracy" which one inevitably encounters whenever one considers approximate solutions of the quantum equation.
THREE-DIMENSIONAL QUANTUM GRAVITY AS DYNAMICAL TRIANGULATION
Authors: AGISHTEIN M. E. , MIGDAL A. A.
Published: November 2004

The dynamical triangulation model of 3-dimensional Quantum Gravity is defined and studied. We propose two different algorithms for numerical simulations, leading to consistent results. One is the 3-dimensional generalization of the bonds flip, another is more sophisticated algorithm, based on Schwinger–Dyson equations. We found such care necessary, because our results appear to be quite unexpected.

We simulated up to 60000 tetrahedra and observed none of the feared pathologies like factorial growth of the partition function with volume, or collapse to the branched polymer phase. The volume of the Universe grows exponentially when the bare cosmological constant λ approaches the critical value λ c from above, but the closed Universe exists and has peculiar continuum limit. The Universe compressibility diverges as (λ − λ c )−2 and the bare Newton constant linearly approaches negative critical value as λ goes to λ c , provided the average curvature is kept at zero. The fractal properties turned out to be the same, as in two dimensions, namely the effective Hausdorff dimension grows logarithmically with the size of the test geodesic sphere.
LOOP EQUATIONS IN MATRIX MODELS AND IN 2D QUANTUM GRAVITY
Authors: MAKEENKO YU.
Published: November 2004

A brief review of recent applications of loop equations to the matrix models and to 2-dimensional quantum gravity is given. Results concerning multi-loop correlators for low genera and Virasoro invariance are discussed.
CHERN–SIMONS TERMS AND ANOMALIES IN GAUGE THEORIES
Authors: BANERJEE R.
Published: November 2004

The parity-violating effective action for theories of fermions coupled to external gauge fields in arbitrary odd dimensions is calculated exactly by a perturbative technique. This effective action is used to obtain the structures for the Chern–Simons terms in odd dimensions and anomalies in even dimensions. Our analysis clearly elucidates the connection of the Chern–Simons terms with the covariant and consistent anomalies.
INFLATION-DRIVEN STRING INSTABILITIES: TOWARDS A SYSTEMATIC LARGE-R EXPANSION
Authors: HAN NGUYEN SUAN , VENEZIANO G.
Published: November 2004

We present the general structure of a large-R expansion for the evolution of classical strings during a phase of fast inflation together with explicit results for several subleading terms. We are thus able to check the consistency of the expansion and to describe the approach to asymptopia both in terms of string shapes and of their equation of state.
SYMMETRY BREAKING AS A CONSEQUENCE OF STABILIZATION OF A BOTTOMLESS THEORY
Authors: BOGOJEVIĆ A. R.
Published: November 2004

The Greensite–Halpern stabilization technique is applied to d = 0 Euclidean field theories. The effective action is calculated using WKB as well as a variational approach. For a set of free theories with non-trivial measure the effective action is computed exactly, and a comparison is made with the results of approximate techniques. The effect of stabilization on the measure is to bring in a "centrifugal barrier" term that breaks parity invariance. A model with quartic interaction of wrong sign is also analyzed in the limit of large coupling.
IS THE ELECTRON A "RIGID" PARTICLE?
Authors: FIORENTINI G. , GASPERINI M. , SCARPETTA G.
Published: November 2004

We consider an extended point-particle action depending not only on the length but also on the curvature of the particle world-line. We derive constraints on such a higher derivative modification of standard dynamics, by using experimental results on the hyperfine structure of the hydrogen atom and on the electron (g − 2) anomaly.
SUPERMATRIX MODELS
Authors: ALVAREZ-GAUMÉ L. , MAÑES J. L.
Published: November 2004

We consider a very general class of supermatrix models. The result of our analysis is rather surprising but disappointing: all these models are strictly equivalent to theories based on ordinary matrices. This suggests that using supermatrices is not the right way to find a discretization of 2D supergravity.
NON-RENORMALIZABILITY OF THE MASSIVE N = 2 SUPER-YANG–MILLS THEORY
Authors: KHELASHVILI G. A. , OGIEVETSKY V. I.
Published: November 2004

The massive N = 2 supersymmetric Yang–Mills theory is investigated. Its non-renormalizability is revealed starting from the fourth order of the perturbation theory. The N = 2 harmonic superspace approach and the Stueckelberg-like formalism are used. The Stueckelberg fields form some nonlinear sigma model. Non-renormalizability of the latter produces non-renormalizability of the N = 2 supersymmetric Yang–Mills theory.
WORMHOLE SOLUTIONS WITH GAUSS–BONNET TERM IN HIGHER DIMENSIONS
Authors: XU JIANJUN , JING SICONG
Published: November 2004

Wormhole solution is obtained in higher derivative gravity theory with Gauss–Bonnet term. The corresponding Euclidean action is finite and proportional to the coupling constant of Gauss–Bonnet term. The size of the wormhole is not fixed by the theory but large wormhole is highly suppressed.
TARGET-ASSOCIATED PARTICLE PRODUCTION IN ULTRARELATIVISTIC NUCLEUS-NUCLEUS COLLISIONS
Authors: SENGUPTA K. , JAIN P. L. , SINGH G.
Published: November 2004

We report the multiplicity and angular distributions of the low energy target-associated particles from 32 S and 16 O induced reactions at 200 GeV/nucleon and 16 O induced reactions at 60 GeV/nucleon in emulsion. The results are compared with the Monte-Carlo Code VENUS.
ON SIGNATURE CHANGE IN p-ADIC SPACE-TIMES
Authors: DRAGOVIC BRANKO G.
Published: November 2004

Change of signature by linear coordinate transformations in p-adic space-times is considered. It is shown that there exists arbitrary change of trivial signature in [Formula: see text] for all n≥1 if p≡1( mod 4). In other cases it is possible to change only even number of the signs of the signature. We suggest new concept of signature with respect to distinct quadratic extensions of ℚp. If space-time dimension is restricted to four there is no signature change.
FORM-FACTOR OF RADIATIVE PION DECAY IN QCD
Authors: ALIEV T. M. , OVCHINNIKOV A. A.
Published: November 2004

Axial form-factor of the radiative decay of charged pion is calculated using QCD sum rules method for non-diagonal correlator. For the ratio γ=FA(0)/FV(0) we find γ=0.6±0.15.
TOPOLOGICAL HALF-FLAT GRAVITY
Authors: KUNITOMO HIROSHI
Published: November 2004

A topological field theory modeling the moduli space of half-flat gravitational instantons is presented, in which the fundamental gravitional fields are a trio of self-dual two-forms and an SU(2) connection. The theory can be understand as a topological version of the (Euclidean) Einstein gravity.
ON THE POSSIBILITY OF A SOLUTION TO THE STRONG CP-PROBLEM WITHOUT AXION IN A SU(3)H FAMILY SYMMETRY MODEL
Authors: BEREZHIANI Z. G.
Published: November 2004

It is shown that the 'sea-saw' model of quark mass generation within the SU (3) H gauge horizontal symmetry scheme automatically satisfies the Nelson-Barr criteria for a natural solution of the strong CP-problem if the spontaneous character of CP-violation is supposed. Some possibilities for spontaneous CP-violation are discussed.
RECENT DEVELOPMENTS IN THE THEORY OF ALPHA DECAY
Authors: BUCK B. , MERCHANT A. C. , PEREZ S. M.
Published: November 2004

We examine the extensive experimental data on partial half-lives for alpha-decay, and discuss some interpretations, with emphasis on the use of a simple three parameter cluster model. In this model, the alpha-particle moves in a potential well of fixed depth, in an orbit with a large value of a global quantum number. With the model parameters fixed at values consistent with those suggested by the underlying nucleon orbits, we obtain excellent agreement with the data, and reproduce the discontinuities associated with shell closure in a natural way.
OPEN STRINGS AS Z2-ORBIFOLDS OF CLOSED STRINGS
Authors: NAGAO GREG
Published: November 2004

We present a modular invariant formulation of the open string in terms of the closed string. Chan–Paton factors are understood as multiplicities which arise from a factorization of the closed string. This interpretation of the Chan–Paton factors suggests that the SO (2D/2) open string is consistent to all orders of the loop expansion. We show that the open string may be viewed as a Z2-orbifold of the closed string. Relations are found between various string theories which seem to reinforce an earlier suggestion by Freund that all string theories are derivable from the D = 26 orientable closed bosonic string.
QUANTUM ALGEBRA STRUCTURE OF EXACTLY SOLUBLE QUANTUM SPIN CHAINS
Authors: MEZINCESCU LUCA , NEPOMECHIE RAFAEL I.
Published: November 2004

We consider a large class of quantum spin chains, whose Hamiltonians commute with generators of a quantum algebra and which are integrable. We argue that the corresponding transfer matrices also commute with the quantum algebra. For the spin [Formula: see text] chain, we show that the Bethe states are highest weight states of Uq[ su (2)].
ON TOPOLOGICAL SOLITONS IN U(1) × U(1) PLANAR GAUGE THEORY
Authors: GUILARTE JUAN MATEOS
Published: November 2004

A new of kind of stable topological solitons in a model of the type arising in the effective field theory for the fractional quantum Hall effect has been discovered. Similar solutions also exists in the standard U (1) × U (1) gauge theory of two complex Higgs fields with a quite general Higgs potential describing superconducting strings. The physical and mathematical properties of both types of solitons are discussed.
COULOMB VERSUS STRONG INTERACTION IN CORRELATED NUCLEON EMISSION
Authors: BRACCO M. E. , NAVARRA F. S. , NEMES M. C.
Published: November 2004

We investigate the effect of the Coulomb and strong interaction on double nucleon emission in peripheral heavy ion collisions for incident energies above 1.0 GeV/u. We find that for lower bombarding energies (~1.0 GeV/u) the two contributions are well separated and the two processes lead to double nucleon emission in distinct kinetic energy ranges. The effect of the Coulomb interaction rises logarithmically and becomes dominant at increasing bombarding energies (~100 GeV/u).
CONTINUUM REDUCTION OF VIRASORO-CONSTRAINED LATTICE HIERARCHIES
Authors: SEMIKHATOV A. M.
Published: November 2004

Integrable hierarchies with Virasoro constraints have been observed to describe matrix models. I suggest to define general Virasoro-constrained integrable hierarchies by imposing Virasora-highest-weight conditions on the dressing operators. This simplifies the study of the Virasoro constraints and allows an explicit construction of a scaling which implements the continuum limit of discrete (lattice) hierarchies. Applied to the Toda lattice hierarchy subjected to the Virasoro constraints, this scaling leads to the Virasoro-constrained KP hierarchy. Therefore, in particular, the KP hierarchy is shown to arise as the scaling limit of a matrix model.
TENSOR MODEL FOR GRAVITY AND ORIENTABILITY OF MANIFOLD
Authors: SASAKURA NAOKI
Published: November 2004

We investigate the relation between rank-three tensor models and the dynamical triangulation model of three-dimensional quantum gravity, and discuss the orientability of the manifold and the corresponding tensor models. We generalize the orientable tensor models to arbitrary dimensions, which include the two-dimensional Hermitian matrix model as a special case.
A COMBINED TEST FOR COSMOLOGICAL ANTIMATTER USING THE NEW GENERATION OF γ-RAY TELESCOPES
Authors: GAO YI-TIAN , CLINE DAVID B.
Published: November 2004

In line with the new generation of γ-ray telescopes, further studies of γ-ray cosmology are entering an exciting stage. Interesting models have been proposed to explain the spectrum of the extragalactic γ-ray background (EGB), while intrinsic anisotropies in the EGB can be used to pinpoint some of the theories. In this report, we investigate the observational link of the EGB spectrum and large-scale anisotropies. Emphasizing that spatial anisotropies should be looked for at different observational energies, we propose a combined set of the EGB observations which may turn out to be very powerful in determining the role of antimatter in the early Universe.
DUAL DILATION DYONS
Authors: SHAPERE ALFRED , TRIVEDI SANDIP , WILCZEK FRANK
Published: November 2004

We find four-dimensional black hole solutions of the tree-level string effective action, that carry both electric and magnetic charge. The solutions involve non-trivial axion and dilaton fields, and are related to one another by a form of duality transformation. These black holes have drastically different global properties from the usual charged holes without axions and dilatons. The global causal structures of the effective metrics seen by different types of particles (for the same solution) can differ.
(2, 0) SUPERSYMMETRIC STRING THEORY AND THE CRITICAL EXPONENTS OF THE 3D ISING MODEL
Authors: MOJUMDER M. A.
Published: November 2004

Critical exponents α and β for the 3D Ising model have been obtained by a study of partial non-renormalization of superconformal dimensions of matter fields on (2, 0) supersymmetric string world-sheet. An ansatz has been used to calculate the exact numerical values which are in excellent agreement with experimental and other theoretical results.
AN OPERATOR FORMALISM FOR UNITARY MATRIX MODELS
Authors: ANAGNOSTOPOULOS K. N. , BOWICK M. J. , ISHIBASHI N.
Published: November 2004

We analyze the double scaling limit of unitary matrix models in terms of trigonometric orthogonal polynomials on the circle. In particular we find a compact formulation of the string equation at the kth multicritical point in terms of pseudodifferential operators and a corresponding action principle. We also relate this approach to the mKdV hierarchy which appears in the analysis in terms of conventional orthogonal polynomials on the circle.
WHAT ARE THE ANTI-PARTICLES OF KL,S?
Authors: MATHUR V. S. , RAJEEV S. G.
Published: November 2004

We study the consequences of an anti-unitary symmetry such as CPT for an unstable quantum system described by a non-self-adjoint Hamiltonian. It is shown that CPT invariance by itself does not imply that every particle has an anti-particle of equal mass and life-time. In particular, the neutral kaons KL and KS do not have anti-particles even when CPT is conserved.
A STUDY OF BOUNCE-OFF EFFECT IN 1.1 AGeV139La + Ag(Br) COLLISION
Authors: PALSANIA H. S. , SINGH B. , GILL A. , KUMAR V. , BHALLA K. B. , LOKANATHAN S.
Published: November 2004

From a sample of 896 La + Emulsion interactions, 128 events have been selected for the study of the bounce-off phenomenon. These events correspond to non-central and non-peripheral mode of La + Ag(Br) collision. The back to back correlation in azimuthal plane shows strength of the effect in between the 84 Kr + Ag(Br) and 238 U + Ag(Br) collisions. It is further revealend that the projectile fragments (Z ≥ 3) and alphas (Z = 2) show the same strength of bounce-off their emission characteristics are different. This may throw light on the equilibration of two different zones during flow after the collective stage of bounce-off.
ELECTROWEAK ONE-LOOP CORRECTIONS TO THE LEPTONIC DECAY WIDTH OF W-BOSON, REVISITED
Authors: JUN JIN WOO , JUE CHANGKEUN
Published: November 2004

The eletroweak one-loop corrections to the decay width [Formula: see text] are calculated in the standard model. We have used the on-shell renormalization scheme of K Aoki et al. The full bremsstrahlung effect and the quark mixing effect are taken into account. Both the analytical results and the numerical results are presented.
LANDAU LEVELS AND VERTEX OPERATIONS FOR ANYONS
Authors: DUNNE GERALD V. , LERDA ALBERTO , TRUGENBERGER CARLO A.
Published: November 2004

We construct exact many-body eigenstates of both energy and angular momentum for the N-anyon problem in an external magnetic field. We show that such states span the full ground state eigenspace and arise as correlation functions of Fubini-Veneziano vertex operators of string theory.
VIRASORO ALGEBRA IN THE KN ALGEBRA: BOSONIC STRING WITH FERMIONIC GHOSTS ON RIEMANN SURFACES
Authors: KOIBUCHI HIROSHI
Published: November 2004

The bosonic string model with fermionic ghosts is considered in the framework of the KN algebra. Our attentions are paid to representations of KN algebra and a Clifford algebra of the ghosts. We show that a Virasoro-like algebra is obtained from KN algebra when KN algebra has certain antilinear anti-involution, and that it is isomorphic to the usual Virasoro algebra. We show that there is an expected relation between a central charge of this Virasoro-like algebra and an anomaly of the combined system.
SUSCEPTIBILITY FOR 2-d GRAVITY COUPLED TO SO(2,1) BF SYSTEM
Authors: PICCO MARCO , WALLET JEAN-CHRISTOPHE
Published: November 2004

We consider two-dimensional gravity in the presence of a system of fields described by an action which can be derived from a topological theory with gauge group SO(2,1). Working in the continuum approach, we extract the area dependence of the partition function and deduce the susceptibility for the theory. The inclusion of D massless scalars gives a susceptibility depending linearly on D. We finally discuss our results.
HALL CONDUCTANCE AND EDGE STATES IN THE COULOMB GAS VERTEX OPERATOR FORMALISM
Authors: CRISTOFANO G. , MAIELLA G. , MUSTO R. , NICODEMI F.
Published: November 2004

The fractional quantum Hall effect is discussed in terms of a c = 1 conformal field theory and the associated U(1) Kac–Moody current algebra, using the Coulomb gas vertex operators. A geometrical derivation of the Hall conductance is given and the possible topological order is considered. The consistency requires that only at filling ν = 1/m one of the "particles" described by the vertices can be associated with the electron.
NEW METHOD OF MASSIVE N-POINT FEYNMAN DIAGRAMS CALCULATION
Authors: KOTIKOV A. V.
Published: November 2004

We expand the earlier invented method of massive Feynman diagrams calculation, namely, the differential equations method, to N-point diagrams. We obtain a simple algorithm which allows us to reduce the vertex-type diagram to the propagator-type diagrams, the box-type diagram to the vertex-type diagrams and, in general, the N-point diagram to the (N-1)-point diagrams. We show that this method provides a simple procedure of evaluating the result without D-space integrals (for the dimensional regularization) calculation.
A CRITICAL MATRIX MODEL FOR NON-ORIENTED STRING
Authors: CHEKHOV L. , ZABRODIN A.
Published: November 2004

The Penner-like model of real symmetric matrices with logarithmic potential is solved. We suggest that the double-scaling limit free energy of this model can be interpreted as a generating function for virtual Euler characteristics of moduli space of non-orientable surfaces. The asymptotic expansion in the double-scaling limit is found to coincide with the R=1/4 Gross–Klebanov c=1 model. We also found some amusing correspondences between this model and exactly solvable six-vertex model on square lattice.
THE SPONTANEOUS FERMION NUMBER BREAKING IN QUANTUM ELECTRODYNAMICS WITH MASSIVE PHOTON
Authors: KRASNIKOV N. V.
Published: November 2004

It is shown that in quantum electrodynamics with wrong sign of the photon mass square the fermion number is spontaneously broken and the fermion number violating condensate is different from zero.
QUANTIZATION OF THE FREEDMAN–TOWNSEND MODEL OF MASSIVE VECTOR MESONS
Authors: LEBLANC M. , McKEON D. G. C. , REBHAN A. , SHERRY T. N.
Published: November 2004

We examine a model for massive vector mesons in four dimensions proposed by Freedman and Townsend, where the masses for non-Abelian vector gauge fields are generated without symmetry breaking through a gauge invariant coupling to anti-symmetric tensor fields. The model is quantized using the formalism of Batalin and Vilkovisky. While the Abelian version immediately gives a renormalizable model for massive vector fields, it is shown that in the non-Abelian case the addition of an extra gauge invariant term in the initial Lagrangian leads to an ultraviolet behavior consistent with power-counting renormalizability.
STRING EFFECTIVE ACTION AND TWO-DIMENSIONAL CHARGED BLACK HOLE
Authors: KHASTGIR S. PRATIK , KUMAR ALOK
Published: November 2004

Graviton-dilaton background field equations in three space-time dimensions, following from the string effective action are solved when the metric has only time dependence. By taking one of the two space dimensions as compact, our solution reproduces a recently discovered charged black hole solution in two space-time dimensions. Solutions in the presence of non-vanishing three-dimensional background antisymmetric tensor field are also discussed.
A GENERALIZED REDUCTION PROCEDURE FOR DYNAMICAL SYSTEMS
Authors: LANDI G. , MARMO G. , SPARANO G. , VILASI G.
Published: November 2004

We describe a reduction procedure for dynamical systems. If Γ is a dynamical vector field on a manifold M, a reduced system is obtained by projecting Γ to a manifold Σ/≈ where Σ is a submanifold of M invariant under Γ and ≈ is a suitable equivalence relation.
ON A GRAVITATIONAL EMISSION IN THE CASE OF A NONZERO GRAVITON MASS
Authors: LOSKUTOV YU. M.
Published: November 2004

The intensity of emission of massive gravitons by an arbitary bounded source has been found and its positive definiteness has been proved.
LAX PAIR AND COSMOLOGICAL CONSTANT FOR INDUCED 2D-GRAVITY IN THE LIGHT-CONE GAUGE
Authors: LINA JEAN-MARC , PANIGRAHI PRASANTA K.
Published: November 2004

We present the Lax pair to describe the two-dimensional induced gravity in the light-cone gauge. This is done at the classical level, with the cosmological constant which so far has not been accounted for in this context. The symmetries are discussed, together with some solutions of the integrability conditions. The case of the W3 gravity is also analyzed; exhibiting some special solutions and highlighting the roles of the two cosmological constants in its Lax pair formulation.
FUSION RESIDUES
Authors: INTRILIGATOR KENNETH
Published: November 2004

We discuss when and how the Verlinde dimensions of a rational conformal field theory can be expressed as correlation functions in a topological LG theory. It is seen that a necessary condition is that the RCFT fusion rules must exhibit an extra symmetry. We consider two particular perturbations of the Grassmannian superpotentials. The topological LG residues in one perturbation, introduced by Gepner are shown to be twisted version of the SU (N)k Verlinde dimensions. The residues in the other perturbation are the twisted Verlinde dimensions of another RCFT; these topological LG correlation functions are conjectured to be the correlation functions of the corresponding Grassmannian topological sigma model with a coupling in the action to instanton number.
TRIPLE GAUGE BOSON PRODUCTION IN e+e- COLLISIONS
Authors: NOUS M. H. , El-KISHEN M. , ALGELANI A. M.
Published: November 2004

The production cross-sections for a triple gauge boson has been investigated in both the standard model and the minimal supersymmetric standard model, via e+e-→W+W-Z0. All events that contain the Higgs-boson seem to have no influence in this process.

At [Formula: see text], this process could be detected with a reasonable cross-section, the production mechanism in this case will be e+e-→Z0→W+W-→W+W-Z0.
STRONG INTERACTION CORRECTIONS TO THE DECAY $K\to\pi\nu\bar{\nu}$ for Large mt
Authors: DIB CLAUDIO O. , DUNIETZ ISARD , GILMAN FREDERICK J.
Published: November 2004

We calculate the strong interaction corrections to the decay [Formula: see text] when mt is large. The branching ratios for [Formula: see text] and [Formula: see text] and their sensitivity to these corrections are discussed.
A SIGMA MODEL FOR NEUTRINO MASSES AND MIXINGS AND DECAY
Authors: BARSHAY SAUL
Published: November 2004

I consider the possibility that a sigma model is relevant for calculating the masses and mixings of Dirac neutrinos. New processes involving pairs of Goldstone bosons are predicted, in particular the decay [Formula: see text].
ISOSPIN-DEPENDENT o(4,2) SYMMETRY OF SELF-DUAL WU–YANG MONOPOLES
Authors: HORVÁTHY P. A.
Published: November 2004

A spinless particle in an SU(2) self-dual Wu–Yang monopole field is shown to admit an o(4,2) dynamical symmetry with isospin-dependent generators found previously by Barut and Bornzin. This same symmetry arises for a spinless particle with anomalous charge studied by D'Hoker and Vinet, which we relate to a (spinless) "nucleon" in the self-dual Wu–Yang monopole field.
GENERALIZED SKLYANIN ALGEBRA
Authors: QUANO YAS-HIRO , FUJII AKIRA
Published: November 2004

We propose a [Formula: see text]-Sklyanin algebra to shed new light on elliptic solutions of the Yang–Baxter equation. This object gives a quadratic generalization of the universal enveloping algebra of the Lie algebra [Formula: see text]. We also clarify the meaning of the parameters contained in it.
MODEL DEPENDENCE OF THE NON-MINIMAL SCALAR-GRAVITON EFFECTIVE COUPLING CONSTANT IN CURVED SPACE-TIME
Authors: MUTA T. , ODINTSOV S. D.
Published: November 2004

We investigate the renormalization group behavior of the non-minimal scalar-graviton effective coupling constant in asymptotically free theories (where scalars are elementary) and in a simple four-fermion model (where scalars are composite). We find that this behavior is model-dependent in asymptotically free theories and is asymptotically conformally invariant in the four-fermion model. We observe that the behavior may be altered in more complicated four-fermion models.
ELECTRIC DIPOLE MOMENT OF THE NEUTRON IN THE TWO-FLAVOR SKYRME MODEL
Authors: SALOMONSON PER , SKAGERSTAM BO-STURE , STERN ALLEN
Published: November 2004

We calculate the semiclassical electric dipole moment Dn of the neutron in the two-flavor Skyrme model and compare with other calculations. In terms of the QCD θ-angle we find (including sign) Dn=1.4×10-16θe0cm, where e0 is the electric charge of the proton.
TEST OF QUANTUM ELECTRODYNAMICS USING ULTRA-HIGH SENSITIVE INTERFEROMETERS
Authors: NI WEI-TOU , TSUBONO KIMIO , MIO NORIKATSU , NARIHARA KAZUMICHI , CHEN SHEN-CHE , KING SUN-KUN , PAN SHEAU-SHI
Published: November 2004

For strong fields, quantum electrodynamics tells us that the vacuum is refractive. This can be described by Euler-Heisenberg effective Lagrangian and for B ~ 12 T , the effective index deviates from one of the order of 10-21. Schemes to measure this effect are proposed using ultra-high sensitive interferometers of the type developed for gravity-wave detection. A double modulation scheme is promising in measuring the effect to 1%. For E ~ 5 × 107 V/m and B ~ 12 T , the mixed electric-magnetic effect is also within the reach of detectability.
DISTRIBUTION OF GLUONS IN A FLUX-TUBE
Authors: SCHRAM ZS. , SCHÄFER A. , SAILER K. , GREINER W.
Published: November 2004

The gluon structure function of a flux-tube is estimated using the Weizsäcker-Williams method. It is shown that such string-like gluon fields might give an important contribution to the total gluon structure function of a highly excited hadron.
QUASITRIANGULAR HOPF ALGEBRAS AND YANG-BAXTER EQUATIONS
Authors: MAJID SHAHN
Published: November 2004

This is an informal introduction to the theory of quasitriangular Hopf algebras and its connections with physics. Basic properties and applications of Hopf algebras and Yang-Baxter equations are reviewed, with the quantum group Uq(sl2) as a frequent example. The development builds up to the representation theory of quasitriangular Hopf algebras. Much of the abstract representation theory is new, including a formula for the rank of a representation.
TWO-DIMENSIONAL CHIRAL GAUGE THEORIES IN THE SCHRÖDINGER REPRESENTATION
Authors: RAMALLO A.V.
Published: November 2004

We present a quantization, in the Schrödinger representation, of a two-dimensional theory consisting of an Abelian gauge field coupled to an arbitrary number of right- and left-handed fermions. A consistent and unitary quantum theory is obtained. The gauge symmetry is broken but Lorentz invariance survives quantization. The theory contains a series of chiral massless particles and a massive mode, which can be interpreted as collective excitations of the fields that we have in the initial Lagrangian. Our formalism is quite transparent and allows a clear understanding of the consistency of the model.
PERIODIC COHERENT STATES AND A PATH INTEGRAL FOR SPINS
Authors: KASHIWA TARO
Published: November 2004

A path integral formalism for quantum spins is discussed with the aid of a new coherent state. Under the study, we can see the reason why the path integral formula proposed recently by Nielsen and Rohrlich works so well and the origin of the parameter in their formula. A generalization to the case where spin magnitude is unfixed is also presented.
ONE-LOOP STRING CORRECTIONS TO GAUGE CHARGE
Authors: ROZHANSKY L.V.
Published: November 2004

We derive explicit formulae in terms of ϑ-functions for calculating the one-loop string corrections to the low-energy gauge group charges of the Z3 orbifold. An operator-expansion motivated regularization scheme, which resolves the “0/0” ambiguity arising in such calculations, is proposed and analyzed. An appearance of a special “quadratic-divergent” term, not predicted by a naive field-theoretic analysis, is discussed. Finally we numerically estimate the influence of the massive string states on the renormalization group calculations of the gauge charge.
DERIVING THE FOUR-STRING AND OPEN-CLOSED STRING INTERACTIONS FROM GEOMETRIC STRING FIELD THEORY
Authors: KAKU MICHIO
Published: November 2004

One of the baffling questions concerning the covariant open string field theory is why there are two distinct BRST theories and why the four-string interaction appears in one version but not the other. We solve this mystery by showing that both theories are gauge-fixed versions of a higher gauge theory, called the geometric string field theory, with a new field, a string vierbein [Formula: see text], which allows us to gauge the string length and σ-parametrization. By fixing the gauge, we can derive the “endpoint gauge” (the covariantized light cone gauge), the “midpoint gauge” of Witten, or the “interpolating gauge” with arbitrary string lengths. We show explicitly that the four-string interaction is a gauge artifact of the geometric theory (the counterpart of the four-fermion instantaneous Coulomb term of QED). By choosing the interpolating gauge, we produce a new class of four-string interactions which smoothly interpolate between the endpoint gauge and the midpoint gauge (where it vanishes). Similarly, we can extract the closed string as a bound state of the open string, which appears in the endpoint gauge but vanishes in the midpoint gauge. Thus, the four-string and open-closed string interactions do not have to be added to the action as long as the string vierbein is included.
ON THE FIRST ORDER COVARIANT HAMILTONIAN FORMALISM ON GROUP MANIFOLD
Authors: FOUSSATS A. , ZANDRON O.
Published: November 2004

By considering two explicit examples D=6 and D=11 supergravities we show the applicability, and check the validity of the first order canonical covariant formalism on group manifold. In each case we find the primary constraints, the total Hamiltonian and the field equations of motion. Moreover, we show how the Bianchi identities appear in the covariant Hamiltonian formalism.
THE ELECTROMAGNETIC MASS DIFFERENCE OF PIONS FROM QCD
Authors: MARGVELASHVILI M.
Published: November 2004

It is shown that the two point functions of definite class can be calculated, at small spacelike momenta, as subtraction constants in the Borel transformed QCD sum rules. Using the results of current algebra and PCAC, we obtain three different sum rules for determination of the electromagnetic mass difference of pions. The result is in a good agreement with experiment, and confirms the standard value for the four-quark vacuum condensate.
STUDY OF THE CHARACTERISTICS OF La139 EMULSION INTERACTIONS AT 1.2A GeV
Authors: GILL A. , BHALLA K.B. , KUMAR V. , LOKANATHAN S. , PALSANIA H.S. , SHUKLA V.S. , BHASIN A. , GUPTA V.K. , KITROO S. , MANGOTRA L.K. , RAO N.K.
Published: November 2004

La139 interactions at 1.2A GeV are studied in an emulsion stack exposed at Bevalac (Berkeley). The results on interaction cross-section and mean free path are discussed in the light of geometrical model and compared with the corresponding results from interactions of other projectiles over a wide range of mass (1 to 139). Various multiplicities, multiplicity distributions, multiplicity correlations, angular distributions and rapidity-density distributions are studied and compared with other projectiles.
DISASSEMBLY OF HOT NUCLEI AND RELEVANT PHASE TRANSITION
Authors: BEN-HAO SA , YU-MING ZHENG , XIAO-ZE ZHENG
Published: November 2004

We review the theoretical models describing the disassembly of hot nuclei and the comparisons between the predictions of different models for the distributions of fragments and the corresponding experimental data. Various approaches to the phase transition associated with the disassembly of hot nuclei are also reviewed. The problems needed to be studied further are pointed out briefly.
ANALYSIS OF THE DATA IN HEAVY FLAVOUR DECAYS
Authors: GUPTA V. , SARMA K.V.L.
Published: November 2004

The charmed and bottom hadron decays have been analyzed phenomenologically, keeping both the spectator and nonspectator contributions to the total decay rates. A sum rule relating the total decay widths of the four low-lying charmed baryons is given. It is pointed out that all the data which have become recently available can be understood in all cases with negligible Pauli interference effects but with important exchange- mechanism contributions. Predictions for the lifetimes of [Formula: see text] and [Formula: see text] together with the expected lifetime hierarchy for the bottom hadrons are given. The corresponding semileptonic branching ratios, where possible, are also predicted.
COHERENT STATE QUANTIZATION OF CHERN-SIMONS THEORY
Authors: BOS MICHIEL , NAIR V.P.
Published: November 2004

Three-dimensional Chern-Simons gauge theories are quantized in a functional coherent state formalism. The connection with two-dimensional conformal field theory is found to emerge naturally. The normalized wave functionals are identified as generating functionals for the chiral blocks of two-dimensional current algebra.
BAG INDEPENDENT RELATION FOR SPIN-ISOSPIN PROJECTED BARYONS IN THE CHIRAL BAG PLUS SKYRMION HYBRID MODEL
Authors: KUSAKA K. , TOKI H.
Published: November 2004

We propose an approximate spin-isospin projection method with collective coordinates. We perform the collective rotation in the coordinate space instead of the isospin space and construct a local Lorentz boosted quark field as an approximated solution of the collective rotation. In this projection scheme, we find that the moment of inertia of the quark is expressed by one body operator as the baryon number and the Casimir energy. After the quantization of the rotation, we find for the chiral bag model also the bag independent relations between the magnetic moments and the nucleon-delta mass difference, which have been derived for the Skyrmion.
A COMPARISON OF THE F-SPIN AND NpNn SCHEMES WITH GLOBAL EMPIRICAL SYSTEMATICS
Authors: GUPTA J.B. , HAMILTON J.H. , RAMAYYA A.V.
Published: November 2004

The limitations of the F-spin and the NpNn schemes in reproducing the overall [Formula: see text] systematics in the Z=50−82, N=82−126 shell space are reviewed. The neutron-proton excess or isospin T is shown to play an important role. It determines the position of the β-stability line on the N−Z chart, and explains the existence of isotonic (isotopic) multiplets.
NEW SERIES OF ASYMPTOTICALLY FLAT AXISYMMETRIC AND STATIONARY GRAVITATIONAL SOLUTIONS II
Authors: KYRIAKOPOULOS E.
Published: November 2004

The second solution of a recently found series of asymptotically flat and stationary solutions of the Ernst equation is calculated explicitly as ratio of two sums of monomials. The solution depends on nine arbitrary real constants.
STABILITY OR METASTABILITY AND EIGENVALUES OF THE EQUATION OF SMALL FLUCTUATIONS
Authors: MÜLLER-KIRSTEN H.J.W. , JIAN-ZU ZHANG , TCHRAKIAN D.H.
Published: November 2004

A theory with an asymmetric double-well potential is discussed and shown to possess a nontopological classical configuration like a bounce. It is then shown that the second variational derivative of the Euclidean action at this bounce-like configuration does not possess a negative eigenvalue. The significance of this observation is discussed in relation to more familiar models. Then a theory with a cubic potential is discussed and shown to possess a bounce with one negative eigenvalue of the second variational derivative which is indicative of metastability.
TOPOLOGICAL QUANTUM MECHANICS IN 2+1 DIMENSIONS
Authors: SKAGERSTAM B.-S. , STERN A.
Published: November 2004

We show that the classical and quantum covariant dynamics of spinning particles in flat space in 2+1 dimensions are derived from a pure Wess-Zumino term written on the space of adjoint orbits of the ISO(2, 1) group. Similarly, the dynamics of spinning particles in 2+1 de Sitter [anti-de Sitter] space are derived from a Wess-Zumino term on the space of adjoint orbits of SO(3, 1) [SO(2, 2)]. It is shown that a quantum mechanical description of spin is possible in 2+1 dimensions without introducing explicit spin degrees of freedom, but at the expense of having a noncommutative space-time geometry.
ASYMPTOTIC BEHAVIOR OF PHYSICAL AMPLITUDES IN A FINITE FIELD THEORY
Authors: HELAYËL-NETO J.A. , RAJPOOT S. , SMITH A. WILLIAM
Published: November 2004

Using the N=4 super Yang-Mills theory softly broken by supersymmetric N=1 mass terms for the matter superfields, we compute the one-loop chiral+chiral→antichiral+antichiral scattering amplitude directly in superspace. By suitable choices of the mass parameters, one can endow the model with a hierarchy of light and heavy particles, and the decoupling of the heavy sector from the light-light physical amplitude is studied. We also analyze the high energy limit of the cross section for a two physical scalar scattering and find a (logs) behavior, which then respects the Froissart bound.
CONFORMALLY INVARIANT CONSTRAINED FERMION MODELS
Authors: CABRA D. , MORENO E. , von REICHENBACH C.
Published: November 2004

We construct constrained fermion models within the path-integral framework. By an appropriate choice of constraints we obtain an effective theory with central charge in the minimal unitary series, its supersymmetric generalization and other well-known series. We also discuss the relation between these constrained fermion models and gauged Wess-Zumino-Witten models.
A BIBLIOGRAPHY OF PAPERS ON QUANTUM COSMOLOGY
Authors: HALLIWELL JONATHAN J.
Published: November 2004

This is a reasonably exhaustive list of papers in the field of quantum cosmology, where quantum cosmology is taken to mean the application of quantum gravity to cosmological models. It concentrates mainly on papers published since about 1980. It also includes a less exhaustive list of papers on wormholes and baby universes.
BOUND STATES IN THE "PHYSICAL" QCD2
Authors: SARADZHEV FUAD M.
Published: November 2004

Different variants of the "physical" QCD 2 are analyzed. The role of the chiral background field in the theory is stressed. A massive bound state creating operator in the massless "physical" QCD 2 is constructed.
WEYL FERMION FUNCTIONAL INTEGRAL AND TWO-DIMENSIONAL GAUGE THEORIES
Authors: ALONSO J.L. , CORTÉS J.L. , RIVAS E.
Published: November 2004

In the path integral approach we introduce a general regularization scheme for a Weyl fermionic measure. This allows us to study the functional integral formulation of a two-dimensional U(1) gauge theory with an arbitrary content of left-handed and right-handed fermions. A particular result is that, in contrast with a regularization of the fermionic measure based on a unique Dirac operator, by taking the Dirac fermionic measure as a product of two independent Weyl fermionic measures a consistent and unitary result can be obtained for the Chiral Schwinger Model (CSM) as a byproduct of the arbitrariness in the definition of the fermionic measure.
SIMPLE CURRENTS, MODULAR INVARIANTS AND FIXED POINTS
Authors: SCHELLEKENS A.N. , YANKIELOWICZ S.
Published: November 2004

We review the use of simple currents in constructing modular invariant partition functions and the problem of resolving their fixed points. We present some new results, in particular regarding fixed point resolution. Additional empirical evidence is provided in support of our conjecture that fixed points are always related to some conformal field theory. We complete the identification of the fixed point conformal field theories for all simply laced and most non-simply laced Kac-Moody algebras, for which the fixed point CFT’s turn out to be Kac-Moody algebras themselves. For the remaining non-simply laced ones we obtain spectra that appear to correspond to new non-unitary conformal field theories. The fusion rules of the simplest unidentified example are computed.
FREE ENERGY OF HETEROTIC STRINGS AND COVARIANT LATTICES
Authors: BUDZYŃSKI ROBERT J. , SPALIŃSKI MICHAL A.
Published: November 2004

The free energy of the heterotic string is calculated in the covariant lattice formalism. It is shown that requiring modular invariance and correct statistics leads to a unique answer, which agrees with the known result obtained by path integral methods.
THE CONFORMAL FACTOR AND THE COSMOLOGICAL CONSTANT
Authors: GIDDINGS STEVEN B.
Published: November 2004

The issue of the conformal factor in quantum gravity is examined for Lorentzian signature spacetimes. In Euclidean signature, the “wrong” sign of the conformal action makes the path integral undefined, but in Lorentzian signature this sign is tied to the instability of gravity and once this is accounted for the path integral should be well-defined. In this approach it is not obvious that the Baum-Hawking-Coleman mechanism for suppression of the cosmological constant functions. It is conceivable that since the multiuniverse system exhibits an instability for positive cosmological constant, the dynamics should force the system to zero cosmological constant.
PHASE STRUCTURE IN BOSONIC STRING THEORY
Authors: DALLEY SIMON , MORRIS TIM
Published: November 2004

We carefully reanalyze a lattice model of oriented closed bosonic strings in light cone gauge due to Klebanov and Susskind, completing the procedure suggested by these authors for solving for the spectrum. Our results enable us to relate the concept of minimum distance in bosonic string theory in uncompactified space to the phase structure of strings on tori, and in particular their duality symmetry. Generalizations to a theory of arbitrary dimension are given.
FRACTAL STRUCTURE OF TWO-DIMENSIONAL SUPERGRAVITY IN THE SUPERCONFORMAL GAUGE
Authors: APIKYAN S. A.
Published: November 2004

Two-dimensional induced quantum supergravity is analyzed. By the use of a superconformal gauge we derive the results of Polyakov and Zamolodchikov for the spectrum of anomalous dimensions of a conformal superfield. Their conjecture for the "string entropy exponent" γ for supergravity is proven and extended to an arbitrary genus surface.