October 1999 arXiv papers — page 18

Zurab Kakushadze

We point out that in (open) string compactifications with non-zero NS-NS B-field we can have large Kaluza-Klein thresholds even in the small volume limit. In this limit the corresponding gauge theory description is in terms of a compactification on a non-commutative space (e.g., a torus or an orbifold thereof). Based on this observation we discuss a brane wo

Teodor Banica

We consider commuting squares of finite dimensional von Neumann algebras having the algebra of complex numbers in the lower left corner. Examples include the vertex models, the spin models (in the sense of subfactor theory) and the commuting squares associated to finite dimensional Kac algebras. To any such commuting square we associate a compact Kac algebra

Qing Wang, Yu-Ping Kuang, Xue-Lei Wang, Ming Xiao

The normal part of the Gasser-Leutwyler formulation of the chiral Lagrangian is formally derived from the first principles of QCD without taking approximations. All the coefficients are expressed in terms of certain Green's functions in QCD, which can be regarded as the general QCD definitions of the normal part of the coefficients. The approximate value

Bernard F Schutz

Data of good quality is expected from a number of gravitational wave detectors within the next two years. One of these, GEO600, has special capabilities, such as narrow-band operation. I describe here the preparations that are currently being made for the analysis of GEO600 data.

Keith Watt, Charles W. Misner

We present here a relativistic theory of gravity in which the spacetime metric is derived from a single scalar field $Φ$. The field equation, derived from a simple variational principle, is a non-linear flat-space four-dimensional wave equation which is particularly suited for numerical evolution. We demonstrate that while this theory does not generate resul

Claudio J. Tessone, Horacio S. Wio

We analyze the effect of the simultaneous presence of correlated additive and multiplicative noises on the stochastic resonance response of a modulated bistable system. We find that when the correlation parameter is also modulated, the system's response, measured through the output signal-to-noise ratio, becomes largely independent of the additive noise

P. J. Jensen, K. H. Bennemann, P. Poulopoulos, M. Farle

Motivated by recent experiments, the effect of the interlayer exchange interaction $J_{inter}$ on the magnetic properties of coupled Co/Cu/Ni trilayers is studied theoretically. Here the Ni film has a lower Curie temperature $T_{C,\rm Ni}$ than the Co film in case of decoupled layers. We show that by taking into account magnetic fluctuations the interlayer c

Torsten Andersen, Ole Keller

The phase conjugated response from nonmagnetic multi-level metallic quantum wells is analyzed and an essentially complete analytical solution is presented and discussed. The description is based on a semi-classical local-field theory for degenerate four-wave mixing in mesoscopic interaction volumes of condensed media developed by the present authors [T. Ande

E. Hascoet, H. Herrmann

We numerically investigate the problem of the propagation of a shock in an horizontal non-loaded granular chain with a bead interaction force exponent varying from unity to large values. When $α$ is close to unity we observed a cross-over between a nonlinearity-dominated regime and a solitonic one, the latest being the final steady state of the propagating w

H. W. J. Blöte, J. R. Heringa, M. M. Tsypin

We study the three-dimensional Ising model at the critical point in the fixed-magnetization ensemble, by means of the recently developed geometric cluster Monte Carlo algorithm. We define a magnetic-field-like quantity in terms of microscopic spin-up and spin-down probabilities in a given configuration of neighbors. In the thermodynamic limit, the relation b

Ophir M. Auslaender, Shmuel Fishman

The autocorrelation function of the force acting on a slow classical system, resulting from interaction with a fast quantum system is calculated following Berry-Robbins and Jarzynski within the leading order correction to the adiabatic approximation. The time integral of the autocorrelation function is proportional to the rate of dissipation. The fast quantu

Christian Theis, Stefan Harfst

Modeling of interacting galaxies suffers from an extended parameter space prohibiting traditional grid based search strategies. As an alternative approach a combination of a Genetic Algorithm (GA) with fast restricted N-body simulations can be applied. A typical fit takes about 3-6 CPU-hours on a PentiumII processor. Here we present a parallel implementation

T. Bremnes, B. Binggeli, P. Prugniel

We have carried out CCD photometry in the Cousins B and R bands of 15 galaxies in the Canes Venatici I cloud. Total magnitudes, effective radii, effective surface brightnesses, as well as galaxy radii at various isophotal levels in both colors were determined. Best-fitting exponential parameters and color gradients are also given for these galaxies. The phot

Adi Nusser, Ofer Lahav

The Ly-alpha forest provides important constraints on the smoothness of the universe on large scales. We calculate the flux distribution along line-of-sight to quasars in a universe made of randomly distributed clumps, each of them with a Rayleigh-L`evi fractal structure. We consider the probability distribution function of the normalised flux in the line-of

I. Anderson, M. Fels, C. Torre

We extend Lie's classical method for finding group invariant solutions to the case of non-transverse group actions. For this extension of Lie's method we identify a local obstruction to the principle of symmetric criticality. Two examples of non-transverse symmetry reductions for the potential form of Maxwell's equations are then examined.

A. G. Akeroyd, A. Arhrib, C. Dove

We consider single charged Higgs ($H^{\pm}$) and pseudoscalar Higgs ($A^0$) production in association with a gauge boson at $μ^+μ^-$ colliders. We find that the tree-level t-channel and s-channel contributions to $μ^+μ^-\to H^{\pm}W^{\mp}, A^0Z$ are enhanced for large values of $\tanβ$, allowing sizeable cross-sections whose analogies at $e^+e^-$ colliders w

Jijun Zhao, Alper Buldum, Jie Han, Jian Ping Lu

We studied Li intercalated carbon nanotube ropes by using first principles methods. Our results show charge transfer between Li and C and small structural deformation of nanotube due to intercalation. Both inside of nanotube and the interstitial space are susceptible for intercalation. The Li intercalation potential of SWNT rope is comparable to that of grap

Dik Bouwmeester, Jian-Wei Pan, Harald Weinfurter, Anton Zeilinger

Quantum teleportation is one of the essential primitives of quantum communication. We suggest that any quantum teleportation scheme can be characterized by its efficiency, i.e. how often it succeeds to teleport, its fidelity, i.e. how well the input state is reproduced at the output, and by its insensitivity to cross talk, i.e. how well it rejects an input s

L. Lanz, O. Melsheimer, B. Vacchini

For an isolated macrosystem classical state parameters $ζ(t)$ are introduced inside a quantum mechanical treatment. By a suitable mathematical representation of the actual preparation procedure in the time interval $[T,t_0]$ a statistical operator is constructed as a solution of the Liouville von Neumann equation, exhibiting at time $t$ the state parameters

J. M. G. Sancho, S. F. Huelga

The problem of the experimental determination of the amount of entanglement of a bipartite pure state is addressed. We show that measuring a single observable does not suffice to determine the entanglement of a given unknown pure state of two particles. Possible minimal local measuring strategies are discussed and a comparison is made on the basis of their b

Hélène Esnault, I-Hsun Tsai

In Comm. Math. Physics 118 (1988), 651-701, A. Beilinson and V. Schechtman define on the total space of a smooth family of curves a so-called trace complex associated to a vector bundle, the 0-th relative cohomology of which is the Atiyah algebra of the determinant bundle. Their proof reduces the general case to the acyclic one. In particular, one needs a co

David B. Wilson

We give a new method for generating perfectly random samples from the stationary distribution of a Markov chain. The method is related to coupling from the past (CFTP), but only runs the Markov chain forwards in time, and never restarts it at previous times in the past. The method is also related to an idea known as PASTA (Poisson arrivals see time averages)

M. Reuter

For the description of space-time fermions, Dirac-Kähler fields (inhomogeneous differential forms) provide an interesting alternative to the Dirac spinor fields. In this paper we develop a similar concept within the symplectic geometry of phase-spaces. Rather than on space-time, symplectic Dirac-Kähler fields can be defined on the classical phase-space of an

Yishi Duan, Libin Fu, Hong Zhang

From the topological properties of a three dimensional vector order parameter, the topological current of point defects is obtained. One shows that the charge of point defects is determined by Hopf indices and Brouwer degrees. The evolution of point defects is also studied. One concludes that there exist crucial cases of branch processes in the evolution of

Torbjörn Sjöstrand

Heavy objects like the W, Z and t are short-lived compared with typical hadronization times. When pairs of such particles are produced, the subsequent hadronic decay systems may therefore become interconnected. We study such potential effects at Linear Collider energies.

V. E. Kravtsov, B. L. Altshuler

AC noise in disordered conductors causes both dephasing of the electron wave functions and a DC current around a mesoscopic ring. We demonstrate that the dephasing rate tau_ϕ^{-1} in long wires and the DC current, induced by the same noise and averaged over an ensemble of small rings are connected. The ensemble-averaged h/2e flux harmonic <I> of the current

C. Stephen Hellberg, E. Manousakis

This is a Reply to the Comment of S.R. White and D.J. Scalapino [cond-mat/9907243] on our recent paper ``Stripes and the t-J Model&#39;&#39; [Physical Review Letters 83, 132 (1999) and cond-mat/9812022].

Kenichiro Aoki, Dimitri Kusnezov

We study nonequilibrium properties of a one-dimensional lattice Hamiltonian with quartic interactions in strong thermal gradients. Nonequilibrium temperature profiles, T(x), are found to develop significant curvature and boundary jumps. From the determination of the bulk thermal conductivity, we develop a quantitative description of T(x) including the jumps.

Valerio Faraoni, Edgard Gunzig

Scalar-tensor theories of gravity can be formulated in the Jordan or in the Einstein frame, which are conformally related. The issue of which conformal frame is physical is a contentious one; we provide a straightforward example based on gravitational waves in order to clarify the issue.

D. O. Caldwell, G. M. Fuller, Y. -Z. Qian

A light sterile neutrino species has been introduced to explain simultaneously the solar and atmospheric neutrino puzzles and the results of the LSND experiment, while providing for a hot component of dark matter. Employing this scheme of neutrino masses and mixings, we show how matter-enhanced active-sterile neutrino transformation followed by active-active

R. R. Gal, R. R. DeCarvalho, S. C. Odewahn, S. G. Djorgovski

The Northern Sky Optical Cluster Survey is a project to create an objective catalog of galaxy clusters over the entire high-galactic-latitude Northern sky, with well understood selection criteria. We use the object catalogs generated from the Digitized Second Palomar Sky Survey (DPOSS, Djorgovski et al. 1999) as the basis for this survey. We apply a color cr

C. A. Nelson, K. H. Cook, P. Popowski, D. A. Alves

We present UBV photometry of the eclipsing binary Harvard Variable 2274 in the Large Magellanic Cloud (LMC). The stellar parameters of this binary system were calculated by Guinan et al. (1998a) who gave both a reddening towards HV 2274 of E(B-V) = 0.083 +/- 0.006 and a distance modulus to the LMC, mu_{LMC} = 18.42 +/- 0.007. The reddening of this system was

C. Grojean, J. Cline, G. Servant

We propose a supergravity inspired derivation of a Randall-Sundrum&#39;s type action as an effective description of the dynamics of a brane coupled to the bulk through gravity only. The cosmological constants in the bulk and on the brane appear at the classical level when solving the equations of motion describing the bosonic sector of supergravities in ten

A. W. P. Poon, R. J. Komar, C. E. Waltham, M. C. Browne

The Sudbury Neutrino Observatory (SNO) is a new 1000-tonne D2O Cerenkov solar neutrino detector. A high energy gamma-ray source is needed to calibrate SNO beyond the 8B solar neutrino endpoint of 15 MeV. This paper describes the design and construction of a source that generates 19.8-MeV gamma rays using the 3H(p,gamma)4He reaction (``pt&#39;&#39;), and demo

O. H. Hald

The method of optimal prediction is applied to calculate the future means of solutions to the Klein-Gordon equation. It is shown that in an appropriate probability space, the difference between the average of all solutions that satisfy certain constraints at time t=0, and the average computed by an approximate method, is small with high probability.

Arkadi A. Odintsov

We investigate electronic properties of heterojunctions between metallic and semiconducting single-wall carbon nanotubes. Ineffective screening of the long range Coulomb interaction in one-dimensional nanotube systems drastically modifies the charge transfer phenomena compared to conventional semiconductor heterostructures. The length of depletion region var

I. I. Smolyaninov, H. Y. Liang, S. Aggarwal, R. Ramesh

We present a near-field optical technique for second harmonic imaging using bare tapered optical fiber tip illuminated with femtosecond laser pulses. Enhancement of electric field at the tip of the fiber results in enhanced second harmonic generation (SHG) from the sample region near the tip. This SH emission is collected by the same tapered fiber. Spatial d

Oliver Redner, Michael Baake

We demonstrate that the invaded cluster algorithm, recently introduced by Machta et al, is a fast and reliable tool for determining the critical temperature and the magnetic critical exponent of periodic and aperiodic ferromagnetic Ising models in two dimensions. The algorithm is shown to reproduce the known values of the critical temperature on various peri

A. Udalski

We present relation of the mean I-band brightness of red clump stars on metallicity. Red clump stars were proposed to be a very attractive standard candle for distance determination. The calibration is based on 284 nearby red giant stars whose high quality spectra allowed to determine accurate individual metal abundances. High quality parallaxes (\sigma_\pi

Sebastiano Ghigna, Ben Moore, Fabio Governato, George Lake

Can N-body simulations reliably determine the structural properties of dark matter halos? Focussing on a Virgo-sized galaxy cluster, we increase the resolution of current ``high resolution simulations&#39;&#39; by almost an order of magnitude to examine the convergence of the important physical quantities. We have 4 million particles within the cluster and f

S. D. Paganis, G. W. Hoffmann, R. L. Ray, J. -L. Tang

The baryon-baryon continuum invariant mass spectrum generated from relativistic nucleus + nucleus collision data may reveal the existence of doubly-strange dibaryons not stable against strong decay if they lie within a few MeV of threshold. Furthermore, since the dominant component of these states is a superposition of two color-octet clusters which can be p

Hyun-Chul Kim, Michal Praszalowicz, Klaus Goeke

We investigate the hyperon semileptonic decays and the quark spin content of the proton $ΔΣ$ taking into account flavor SU(3) symmetry breaking. Symmetry breaking is implemented with the help of the chiral quark-soliton model in an approach, in which the dynamical parameters are fixed by the experimental data for six hyperon semileptonic decay constants. As

G. Martinez, L. Aphecetche, Y. Charbonnier, H. Delagrange

We report on a measurement of hard photons (Eg>30 MeV) in the reaction Ar+Ca at 180A MeV at an energy in which photons from the decay of pi0 mesons are dominating. Simultaneous measurement with the TAPS spectrometer of the photon spectrum and photon-photon coincidences used for the identification of pi0 enabled the subtraction of pi0 contribution. The result

P. Duclos, P. Exner, D. Krejcirik

We consider a quantum particle constrained to a curved layer of a constant width built over an infinite smooth surface. We suppose that the latter is a locally deformed plane and that the layer has the hard-wall boundary. Under this assumptions we prove that the particle Hamiltonian possesses geometrically induced bound states.

Bert Janssen

We construct p-brane solutions with non-trivial world volume metrics and show that applied to supergravity theories, they will lead to threshold BPS bound states of intersecting solutions. However applied to certain specific values of the couplings in cosmological (a,b)-models non-trivial solutions can be constructed.

S. Groot Nibbelink

The scalars of an N = 1 supersymmetric sigma-model in 4 dimensions parameterize a Kaehler manifold. The transformations of their fermionic superpartners under the isometries are often anomalous. These anomalies can be canceled by introducing additional chiral multiplets with appropriate charges. To obtain the right charges a non-trivial singlet compensating

S. Ayal, T. Piran, R. Oechslin, M. B. Davies

We introduce an adaptation of the well known Tree+SPH numerical scheme to Post Newtonian (PN) hydrodynamics and gravity. Our code solves the (0+1+2.5)PN equations. These equations include Newtonian hydrodynamics and gravity (0PN), the first order relativistic corrections to those (1PN) and the lowest order gravitational radiation terms (2.5PN). We test vario

S. N. Molotkov, S. S. Nazin

A relativistic quantum information exchange protocol is proposed allowing two distant users to realize ``coin tossing&#39;&#39; procedure. The protocol is based on the point that in relativistic quantum theory reliable distinguishing between the two orthogonal states generally requires a finite time depending on the structure of these states.

J. P. Pekola, L. J. Taskinen, Sh. Farhangfar

We have investigated one and two dimensional (1D and 2D) arrays of tunnel junctions in partial Coulomb blockade regime. The absolute accuracy of the Coulomb blockade thermometer is influenced by the external impedance of the array, which is not the same in the different topologies of 1D and 2D arrays. We demonstrate, both by experiment and by theoretical cal

Michael Tsamparlis, Pantelis S. Apostolopoulos

We present two counterexamples to the paper by Carot et al. in Gen. Rel. Grav. 1997, 29, 1223 and show that the results obtained are correct but not general.

A. C. de la Torre, A. Daleo, I. Garcia-Mata

The legendary discussion between Einstein and Bohr concerning the photon box experiment is critically analyzed. It is shown that Einstein&#39;s argument is flawed and Bohr&#39;s reply is wrong.

Johann Summhammer

Recently, there has been a discussion on the origin of the quantum probability rules (Deutsch quant-ph/9906015, Polley quant-ph/9906124, Barnum et al. quant-ph/9907024, Finkelstein quant-ph/9907004). This contribution, which is a slightly reformulated version of a paper published in Int.J.Theor.Phys. 33, 171 (1994), points out the follwoing: To an experiment

J. Negro, L. M. Nieto, O. Rosas-Ortiz

A generalization of the factorization technique is shown to be a powerful algebraic tool to discover further properties of a class of integrable systems in Quantum Mechanics. The method is applied in the study of radial oscillator, Morse and Coulomb potentials to obtain a wide set of raising and lowering operators, and to show clearly the connection that lin

Berthold-Georg Englert, Marlan O. Scully, Herbert Walther

In a recent publication Luis and Sanchez-Soto arrive at the conclusion that complementarity is universally enforced by random classical phase kicks. We disagree. One could just as well argue that quantum entanglement is the universal mechanism. Both claims of universality are unjustified, however.

W. a. Hofer

In view of experimentally obtainable resolutions, equal to the Compton wavelength of an electron, the conventional interpretation of quantum mechanics no longer seems to provide a sufficiently subtle tool. Based on the intrinsic properties of extended particles we propose a new theory, which allows to describe fundamental processes with unlimited precision a

Howard Barnum, Herbert J. Bernstein, Lee Spector

We give the first quantum circuit for computing $f(0)$ OR $f(1)$ more reliably than is classically possible with a single evaluation of the function. OR therefore joins XOR (i.e. parity, $f(0) \oplus f(1)$) to give the full set of logical connectives (up to relabeling of inputs and outputs) for which there is quantum speedup. The XOR algorithm is of fundamen

Burkhard Militzer, William Magro, David Ceperley

Fermionic path integral Monte Carlo simulations have been applied to study the equilibrium properties of the hydrogen and deuterium in the density and temperature range of 1.6 < rs < 14.0 and 5000K < T < 167000K. We use this technique to determine the phase diagram by identifying the plasma, the molecular, atomic and metallic regime. We explain how one can i

Burkhard Militzer, E. L. Pollock

A new variational principle for optimizing thermal density matrices is introduced. As a first application, the variational many body density matrix is written as a determinant of one body density matrices, which are approximated by Gaussians with the mean, width and amplitude as variational parameters. The method is illustrated for the particle in an externa

V. I. Marchenko

The physical idea of the natural origin of diseases and deaths has been presented. The fundamental microscopical reason is the destruction of any metastable state by thermal activation of a nucleus of a nonreversable change. On the basis of this idea the quantitative theory of age dependence of death probability has been constructed. The obtained simple Deat

K. Rutz, M. Bender, P. -G. Reinhard, J. A. Maruhn

The phenomenological adjustment of the nuclear pairing strength is usually performed with respect to the odd-even staggering of the binding energies. We find that the results strongly depend on the way in which the ground states of the odd nuclei are computed. A thorough calculation including all time-even and time-odd polarisation effects induced by the odd

M. Bender, K. Rutz, P. -G. Reinhard, J. A. Maruhn

We study the influence of the scheme for the correction for spurious center-of-mass motion on the fit of effective interactions for self-consistent nuclear mean-field calculations. We find that interactions with very simple center-of-mass correction have significantly larger surface coefficients than interactions for which the center-of-mass correction was c

J. E. Amaro, F. Arias de Saavedra, A. M. Lallena, G. Co&#39;

The inclusive electromagnetic responses in the quasi-elastic region are calculated with a model which considers the terms of the cluster expansion containinga single correlation line. The validity of this model is studied by comparing, in nuclear matter, its results with those of a complete calculation. Results in finite nuclei for both one-and two-nucleon e

L. Ahle

Positive pion and kaon production from Au+Au reactions have been measured as a function of beam energy over the range 2.0-10.7~AGeV. Both the kaon and the pion production cross-sections at mid-rapidity are observed to increase steadily with beam kinetic energy. The ratio of K$^+$ to $\pi^+$ mid-rapidity yields increases from 0.0271$\pm0.0015\pm0.0014$ at 2.0

J. Wess

This lecture consists of two sections. In section 1 we consider the simplest version of a q-deformed Heisenberg algebra as an example of a noncommutative structure. We first derive a calculus entirely based on the algebra and then formulate laws of physics based on this calculus. Then we realize that an interpretation of these laws is only possible if we stu

Kefeng LIU, Xiaonan MA

In this paper, we first prove a local family version of the Atiyah-Bott-Segal-Singer Lefschetz fixed point formula, then we extend the famous Witten&#39;s rigidity Theorems to the family case. Several family vanishing theorems for elliptic genera are also proved.

Jonathan M. Borwein, David M. Bradley, David J. Broadhurst, Petr Lisonek

Historically, the polylogarithm has attracted specialists and non-specialists alike with its lovely evaluations. Much the same can be said for Euler sums (or multiple harmonic sums), which, within the past decade, have arisen in combinatorics, knot theory and high-energy physics. More recently, we have been forced to consider multidimensional extensions enco

Lyonell S. Boulton

We provide new information concerning the pseudospectra of the complex harmonic oscillator. Our analysis illustrates two different techniques for getting resolvent norm estimates. The first uses the JWKB method and extends for this particular potential some results obtained recently by E.B. Davies. The second relies on the fact that the bounded holomorphic s

Ronald Fintushel, Ronald J. Stern

The purpose of this paper is to investigate the following problem: For a fixed 2-dimensional homology class K in a simply connected symplectic 4-manifold, up to smooth isotopy, how many connected smoothly embedded symplectic submanifolds represent K? We show that when K can be represented by a symplectic torus, there are many instances when K can be represen

Byung-Jay Kahng

The dual Lie bialgebra of a certain ``quasitriangular&#39;&#39; Lie bialgebra structure on the Heisenberg Lie algebra determines a (non-compact) Poisson--Lie group G. The compatible Poisson bracket on G is non-linear, but it can still be realized as a ``cocycle perturbation&#39;&#39; of the linear Poisson bracket. We construct a certain twisted group C*-alge

Gary T. Horowitz

A very brief review is given of some of the developments leading to our current understanding of black holes in string theory. This is followed by a discussion of two possible misconceptions in this subject - one involving the stability of small black holes and the other involving scale radius duality. Finally, I describe some recent results concerning quasi

J. A. Helayel-Neto, A. Penna-Firme, I. L. Shapiro

The leading long-distance 1-loop quantum corrections to the Coulomb potential are derived for scalar QED and their gauge-independence is explicitly checked. The potential is obtained from the direct calculation of the 2-particle scattering amplitude, taking into account all relevant 1-loop diagrams. Our investigation should be regarded as a first step toward

P. Bantay

A general theory of permutation orbifolds is developed for arbitrary twist groups. Explicit expressions for the number of primaries, the partition function, the genus one characters, the matrix elements of modular transformations and for fusion rule coefficients are presented, together with the relevant mathematical concepts, such as Lambda-matrices and twis

J. Navarro-Salas, P. Navarro

We provide a realization of the AdS$_2$/CFT$_1$ correspondence in terms of asymptotic symmetries of the AdS$_2\times$S$^1$ and AdS$_2\times$S$^2$ geometries arising in near-extremal BTZ and Reissner-Nordström black holes. Cardy&#39;s formula exactly accounts for the deviation of the Bekenstein-Hawking entropy from extremality. We also argue that this result

K. -H. Rehren

The AdS-CFT correspondence is established as a re-assignment of localization to the observables which is consistent with locality and covariance.

Yishi Duan, Libin Fu

By means of the geometric algebra the general decomposition of SU(2) gauge potential on the sphere bundle of a compact and oriented 4-dimensional manifold is given. Using this decomposition theory the SU(2) Chern density has been studied in detail. It shows that the SU(2) Chern density can be expressed in terms of the $δ-$function $δ(ϕ) $. And one can find t

Daniele Binosi

It is pointed out that it is very unlikely that we can find analytical solutions built up from elementary functions for the domain wall junctions problem in Wess-Zumino models possessing a trivial Kahler potential.

Tomas Sykora

We calculate the equal-time commutator of two fermionic currents within the framework of the 1+1 dimensional fully quantized theory, describing the interaction of massive fermions with a massive vector boson. It is shown that the interaction does not change the result obtained within the theory of free fermions.

Bo Andersson, Haiming Hu

The well-known Monte Carlo simulation packet JETSET is not built in order to describe few-body states (in particular at the few GeV level in e^+e^- annihilation as in BEPC). In this note we will develop the formalism to use the basic Lund Model area law directly for Monte Carlo simulations

M. V. Galynskii, S. M. Sikach

The review of developed by the authors new techniques for covariant calculation of matrix elements in QED, the so-called formalism of &#34;Diagonal Spin Basis&#34; (DSB), is presented. In DSB spin 4-vectors of in- and out- fermions are expressed just in terms of their 4-momenta. In this approach the little Lorentz group, common for the initial and final stat

S. Heinemeyer, W. Hollik, G. Weiglein

We review the comparison of the results for the neutral CP-even Higgs-boson masses recently obtained within the Feynman-diagrammatic approach with the previous results based on the renormalization group approach. We show that the results differ by new genuine two-loop contributions present in the Feynman-diagrammatic calculation. The numerical effect of thes

Viktor Hund, Hartmut Pilkuhn

For the S-states of muonium and positronium, the hyperfine shifts to the order $α^6$ of a recently derived two-fermion equation with explicit $\cal CPT$-invariance are checked against the results of a nonrelativistic reduction, and the leading $α^8$ shifts are calculated. An additional hyperfine operator is discovered which can milden the singularity for $r\

A. B. Arbuzov

LABSMC Monte Carlo event generator is used to simulate Bhabha scattering at high energies. Different sources of radiative corrections are considered. The resulting precision is discussed.

P. Duka, J. Gluza, M. Zralek

Quantization and renormalization of the left-right symmetric model is the main purpose of the paper. First the model at tree level with a Higgs sector containing one bidoublet and two triplets is precisely discussed. Then the canonical quantization and Faddeev-Popov Lagrangian are carried out (&#39;t Hooft gauge). The BRST symmetry is discussed. Subsequently

P. Ciafaloni, D. Comelli

We study the leading log infrared behavior of electroweak corrections at TeV scale energies, that will be reached by next generation of linear colliders (NLC). We show that, contrary to what happens at typical LEP energies, it is not anymore possible to disentangle ``pure electroweak&#39;&#39; from ``photonic&#39;&#39; corrections. This means that soft QED e

Jisuke Kubo, Haruhiko Terao, George Zoupanos

We present a method to control the regularization scheme dependence in the running of couplings in Kaluza-Klein theories. Specifically we consider the scalar theory in five dimensions, assuming that one dimension is compactified and we study various regularization schemes in order to analyze concretely the regularization scheme dependence of the Kaluza-Klein

Y. Tsue, D. Vautherin, T. Matsui

We calculate the lifetime of the collective isospin rotating solutions which have been found recently in the case a quantum N-component meson field with exact O(N) symmetry. For this purpose we take into account the small breaking of the O(N) symmetry associated to the non vanishing mass of the pion. This term induces a coupling between collective rotations

Regina Demina, Joseph D. Lykken, Konstantin T. Matchev, Andrei Nomerotski

We estimate the Tevatron Run II potential for top and bottom squark searches. We find an impressive reach in several of the possible discovery channels. We also study some new channels which may arise in non-conventional supersymmetry models. In each case we rely on a detailed Monte Carlo simulation of the collider events and the CDF detector performance in

T. Morii, T. Yamanishi

We propose new formulas for extracting a difference of the polarized light sea-quark density, $Δ\bar d(x)-Δ\bar u(x)$, from polarized deep-inelastic semi-inclusive data. We have estimated the value of it from the present experimental data measured by SMC and HERMES groups. Although the data might suggest a violation of polarized light flavor sea-quark symmet

UKQCD Collaboration, K. C. Bowler, C. M. Maynard, L. Lellouch

A lattice determination of the form factor and decay constants for the semileptonic decay of heavy pseudoscalar (PS) mesons at zero recoil is presented from which the soft pion relation is satisfied. Chiral extrapolation of the form factor is performed at constant $q^2$. Pole dominance is used to extrapolate the form factor in heavy quark mass. At the B mass

M. L. Mangano

I review in this presentation some aspects of phenomenology in High Energy Physics which are related to recent and possibly future progress in lattice QCD. In particular, I cover (i) the extraction of CKM matrix elements from B physics, (ii) the determination of epsilon&#39;/epsilon, as well as (iii) some issues emerged in the physics of high energy jets pro

BES Collaboration

The cross section for charmed meson production at $\sqrt{s} = 4.03 $ and 4.14 GeV has been measured with the Beijing Spectrometer. The measurement was made using 22.3 $pb^{-1}$ of $e^+e^-$ data collected at 4.03 GeV and 1.5 $pb^{-1}$ of $e^+e^-$ data collected at 4.14 GeV. Inclusive observed cross sections for the production of charged and neutral D mesons a

Giampiero Esposito, Cosimo Stornaiolo

The construction of conformally invariant gauge conditions for Maxwell and Einstein theories on a manifold M is found to involve two basic ingredients. First, covariant derivatives of a linear gauge (e.g. Lorenz or de Donder), completely contracted with the tensor field representing the metric on the vector bundle of the theory. Second, the addition of a com

Felix Finster, Joel Smoller, Shing-Tung Yau

In this summary article, we review and discuss the non-existence of stationary black hole solutions for the Einstein-Dirac-Maxwell equations.

J. Podolsky

The extreme Schwarzschild-de Sitter space-time is a spherically symmetric solution of Einstein&#39;s equations with a cosmological constant Lambda and mass parameter m>0 which is characterized by the condition that 9 Lambda m^2=1. The global structure of this space-time is here analyzed in detail. Conformal and embedding diagrams are constructed, and synchro

T. Biedl, E. Demaine, M. Demaine, S. Lazard

In this paper, we study movements of simple polygonal chains in 3D. We say that an open, simple polygonal chain can be straightened if it can be continuously reconfigured to a straight sequence of segments in such a manner that both the length of each link and the simplicity of the chain are maintained throughout the movement. The analogous concept for close

Thomas Lux, D. Sornette

This paper addresses the statistical properties of time series driven by rational bubbles a la Blanchard and Watson (1982), corresponding to multiplicative maps, whose study has recently be revived recently in physics as a mechanism of intermittent dynamics generating power law distributions. Using insights on the behavior of multiplicative stochastic proces

J. A. Giampaoli, D. E. Strier, C. Batista, German Drazer

We have obtained the exact expression of the diffusion propagator in the time-dependent anharmonic potential $V(x,t)={1/2}a(t)x^2+b\ln x$. The underlying Euclidean metric of the problem allows us to obtain analytical solutions for a whole family of the elastic parameter a(t), exploiting the relation between the path integral representation of the short time

Sonali Mukherjee, Hisao Nakanishi

Using a recently introduced mapping between a scalar elastic network tethered at its boundaries and a diffusion problem with permanent traps, we study various vibrational properties of progressively tethered disordered fractals. Different scaling forms are proposed for different types of boundary tethering and numerical investigation of the scaling is perfor

A. J. Bray

The Langevin equation for a particle (`random walker&#39;) moving in d-dimensional space under an attractive central force, and driven by a Gaussian white noise, is considered for the case of a power-law force, F(r) = - Ar^{-sigma}. The `persistence probability&#39;, P_0(t), that the particle has not visited the origin up to time t, is calculated. For sigma

Masahisa Tsuchiizu, Yoshikazu Suzumura

The effect of an alternating potential on a one-dimensional half-filled Hubbard model with repulsive interaction has been examined by applying the renormalization group method to the bosonized Hamiltonian. The electronic state, which is determined by the competition between alternating potential and umklapp scattering, is calculated where the relevance and t