January 2002 arXiv papers

Thomas DeGrand, Urs M. Heller

The quarks in quenched QCD have an anomalous self-interaction in the flavor singlet Goldstone boson channel. This coupling is extracted from a graph with disconnected quark lines, and is used to infer the mass of the eta-prime meson in full QCD. When the fermions are described by an overlap action, the Witten-Veneziano relation is an exact relation between t

Joshua N. Winn, Christopher S. Kochanek, Brian A. McLeod, Emilio E. Falco

We present new Hubble Space Telescope images of the gravitational lens PKS 1830-211, which allow us to characterize the lens galaxy and update the determination of the Hubble constant from this system. The I-band image shows that the lens galaxy is a face-on spiral galaxy with clearly delineated spiral arms. The southwestern image of the background quasar pa

M. A. Braun, F. del Moral, C. Pajares

Recent data show a large difference of the genuine three-body Bose-Einstein correlations in S-Pb collisions and in Pb-Pb central collisions being close to zero in the first case and to one in the second one. These results, unexpected from conventional approaches, are naturally explained by the percolation of colour strings produced in the collisions and subs

L. Homer, Scott F. Anderson, Bruce Margon, Ronald A. Downes

We find convincing observational evidence to confirm the optical identification of the X-ray burster X1746-370 located in the globular cluster NGC6441. Chandra/HRC-I imaging yields a much improved X-ray position for the source, which we show to be fully consistent with our rederived position of a UV-excess star, U1, in the same astrometric reference frame. I

A. Vardi, M. G. Moore

We study spontaneous directionality in the bosonic amplification of atom pairs emitted from an elongated Bose-Einstein condensate (BEC), an effect analogous to `superradiant' emission of atom-photon pairs. Using a simplified model, we make analytic predictions regarding directional effects for both atom-atom and atom-photon emission. These are confirmed

C. Power, J. F. Navarro, A. Jenkins, C. S. Frenk

We present a comprehensive set of convergence tests which explore the role of various numerical parameters on the equilibrium structure of a simulated dark matter halo. We report results obtained with two independent, state-of-the-art, multi-stepping, parallel N-body codes: PKDGRAV and GADGET. We find that convergent mass profiles can be obtained for suitabl

Sean A. Hartnoll

We find a large family of solutions to the Dirac equation on a manifold of $G_2$ holonomy asymptotic to a cone over $S^3 \times S^3$, including all radial solutions. The behaviour of these solutions is studied as the manifold developes a conical singularity. None of the solutions found are both localised and square integrable at the origin. This result is co

R. Iengo, J. G. Russo

We show that the presence of finite-size monopoles can lead to a number of interesting physical processes involving quantum entanglement of charges. Taking as a model the classical solution of the N=2 SU(2) Yang-Mills theory, we study interaction between dyons and scalar particles in the adjoint and fundamental representation. We find that there are bound st

Gabriel Lopes Cardoso, Gianguido Dall'Agata, Dieter Lust

We determine, in the context of five-dimensional ${\cal N}=2$ gauged supergravity with vector and hypermultiplets, the conditions under which curved (non Ricci flat) supersymmetric domain wall solutions may exist. These curved BPS domain wall solutions may, in general, be supported by non-constant vector and hyper scalar fields. We establish our results by a

T. Endoh, T. Morozumi, A. Purwanto

We numerically study the correlation between CP violation in the neutrino oscillations and baryogenesis in the seesaw model. In this study we get the heavy Majorana neutrino masses and lepton number asymmetries from their decays by fitting the data of neutrino oscillations and by working on some hypothesis of the Dirac-Yukawa term for neutrinos.

G. Aarts, D. Ahrensmeier, R. Baier, J. Berges

We derive the nonequilibrium real-time evolution of an O(N) - invariant scalar quantum field theory in the presence of a nonvanishing expectation value of the quantum field. Using a systematic 1/N expansion of the 2PI effective action to next-to-leading order, we obtain nonperturbative evolution equations which include scattering and memory effects. The equi

Sadhan K. Adhikari

Recently, Donley et al. performed an experiment on the dynamics of collapsing and exploding Bose-Einstein condensates by suddenly changing the scattering length of atomic interaction to a large negative value on a preformed repulsive condensate of $^{85}$Rb atoms in an axially symmetric trap. Consequently, the condensate collapses and ejects atoms via explos

J. D. Frankland, R. Bougault, A. Chbihi, S. Hudan

The universal theory of order parameter fluctuations (delta scaling laws) is applied to a wide range of intermediate energy heavy-ion collision data obtained with INDRA. This systematic study confirms that the observed fragment production is compatible with aggregation scenarios for in- or out-of-equilibrium continuous phase transitions, while not showing an

Dag Østvang

The gravitational field exterior respectively interior to a spherically symmetric, isolated body made of perfect fluid is examined within the quasi-metric framework (QMF). It is required that the gravitational field is "metrically static", meaning that it is static except for the effects of the global cosmic expansion on the spatial geometry. Dynamic

Peter W. Shor

We show that for the tensor product of an entanglement-breaking quantum channel with an arbitrary quantum channel, both the minimum entropy of an output of the channel and the Holevo-Schumacher-Westmoreland capacity are additive. In addition, for the tensor product of two arbitrary quantum channels, we give a bound involving entanglement of formation for the

Yang Sun, Javid A. Sheikh, Gui-Lu Long

Nuclear magnetic dipole properties of ground bands and gamma-vibrational bands are studied for the first time using the triaxial projected shell model approach. The study is carried out for the Dy and Er isotopic chains, ranging from transitional to well-deformed region. It is found that the g-factor ratio of the 2^+ state in ground bands to that of gamma-ba

C. Macesanu, C. D. McMullen, S. Nandi

We consider the universal extra dimensions scenario of Appelquist, Cheng, and Dobrescu, in which all of the SM fields propagate into one extra compact dimension, estimated therein to be as large as $\sim (350$ GeV$)^{-1}$. Tree-level KK number conservation dictates that the associated KK excitations can not be singly produced. We calculate the cross sections

V. V. Flambaum, E. V. Shuryak

Recent data on cosmological variation of the electromagnetic fine structure constant from distant quasar (QSO) absorption spectra have inspired a more general discussion of possible variation of other constants. We discuss variation of strong scale and quark masses. We derive the limits on their relative change from (i) primordial Big-Bang Nucleosynthesis (B

J. P. Rodriguez

The question of whether layer decoupling and vortex-lattice melting occur seperately or not in the mixed phase of pristine layered superconductors in the extreme type-II limit is studied through a partial duality analysis of the layered XY model with uniform frustration. We find that both transitions occur simultaneously if the normal/superconducting transit

J. Boerlin, W. Belzig, C. Bruder

We study the statistics of charge transport in a mesoscopic three-terminal device with one superconducting terminal and two normal-metal terminals. We calculate the full distribution of transmitted charges into the two symmetrically biased normal terminals. In a wide parameter range, we find large positive crosscorrelations between the currents in the two no

Yuly Billig

We describe the structure of the irreducible highest weight modules for the twisted Heisenberg-Virasoro Lie algebra at level zero. We prove that such a module is either isomorphic to a Verma module or to a quotient of two Verma modules.

Borut Paul Kersevan, Elzbieta Richter-Was

The AcerMC Monte Carlo generator gives a possibility to generate some of the Standard Model background processes which were recognised as very dangerous for the searches at LHC, and generation of which was either unavailable or not straightforward so far. The program itself provides a library of the massive matrix elements (coded by MADGRAPH) and native phas

V. A. Khoze, A. D. Martin, M. G. Ryskin

The rich structure of photon-exchange processes at hadron colliders is studied. We discuss central vector meson production pp --> p + J/psi + p, W production pp --> p + W + X and mu+ mu- production. Each process has distinct, and large, soft pp rescattering effects, which can be directly observed by detecting the outgoing protons. This allows a probe of the

M. Axenides, L. Perivolaropoulos

The linearity and quietness of the Local ($< 10 Mpc$) Hubble Flow (LHF) in view of the very clumpy local universe is a long standing puzzle in standard and in open CDM cosmogony. The question addressed in this paper is whether the antigravity component of the recently discovered dark energy can cool the velocity flow enough to provide a solution to this puzz

M. J. Davis, S. A. Morgan, K. Burnett

We demonstrate that the time-dependent projected Gross-Pitaevskii equation derived earlier [Davis, et al., J. Phys. B 34, 4487 (2001)] can represent the highly occupied modes of a homogeneous, partially-condensed Bose gas. We find that this equation will evolve randomised initial wave functions to equilibrium, and compare our numerical data to the prediction

P. Rosenbusch, D. S. Petrov, S. Sinha, F. Chevy

We study experimentally and theoretically a cold trapped Bose gas under critical rotation, i.e. with a rotation frequency close to the frequency of the radial confinement. We identify two regimes: the regime of explosion where the cloud expands to infinity in one direction, and the regime where the condensate spirals out of the trap as a rigid body. The form

G. Papini

A recently reported discrepancy between experimental and theoretical values of the muon&#39;s g-2 factor is interpreted as due to small violations of the conservation of P and T in the spin-rotation coupling. The experiments place an upper limit on these violations and on the weight change of spinning gyroscopes.

Benjamin Grinstein, Dan Pirjol

In the heavy quark limit, the form factors for semileptonic and rare radiative B decays into light mesons are related by heavy quark spin symmetry. Here we compute the leading corrections of order Λ/m_Q to these symmetry relations, showing also how to include hard gluon effects to any order in α_s(m_Q). The subleading correction to the form factor relation f

Xinhua Peng, Xiwen Zhu, Ximing Fang, Mang Feng

We have experimentally demonstrated the interferometric complementarity, which relates the distinguishability $D$ quantifying the amount of which-way (WW) information to the fringe visibility $V$ characterizing the wave feature of a quantum entity, in a bulk ensemble by Nuclear Magnetic Resonance (NMR) techniques. We primarily concern on the intermediate cas

M. Ramsey-Musolf, Mark B. Wise

We compute the hadronic light-by-light scattering contributions to the muon anomalous magnetic moment, $\amulbl$, in chiral perturbation theory that are enhanced by large logarithms and a factor of $N_C$. They depend on a low-energy constant entering pseudoscalar meson decay into a charged lepton pair. The uncertainty introduced by this constant is $\pm 60\t

D. N. Chen, Y. P. Jing

We study the angular momentum profile of dark matter halos for a statistical sample drawn from a set of high-resolution cosmological simulations of $256^3$ particles. Two typical Cold Dark Matter (CDM) models have been analyzed, and the halos are selected to have at least $3\times 10^4$ particles in order to reliably measure the angular momentum profile. In

Stanley J. Brodsky, Dae Sung Hwang, Ivan Schmidt

Recent measurements from the HERMES and SMC collaborations show a remarkably large azimuthal single-spin asymmetries A_{UL} and A_{UT} of the proton in semi-inclusive pion leptoproduction. We show that final-state interactions from gluon exchange between the outgoing quark and the target spectator system lead to single-spin asymmetries in deep inelastic lept

Ian Agol, Tao Li

We show that there are algorithms to determine if a 3-manifold contains an essential lamination or a Reebless foliation.

Sonia Paban, Savdeep Sethi, Mark Stern

We study the extent to which the gauge symmetry of abelian Yang-Mills can be deformed under two conditions: first, that the deformation depend on a two-form scale. Second, that the deformation preserve supersymmetry. We show that (up to a single parameter) the only allowed deformation is the one determined by the star product. We then consider the supersymme

Lov K. Grover

Quantum search is a quantum mechanical technique for searching N possibilities in only sqrt(N) steps. This has been proved to be the best possible algorithm for the exhuastive search problem in the sense the number of queries it requires cannot be reduced. However, as this paper shows, the number of non-query operations, and thus the total number of operatio

Jacques Arnaud

Lasers essentially consist of single-mode optical cavities containing two-level atoms with a supply of energy called the pump and a sink of energy, perhaps an optical detector. The latter converts the light energy into a sequence of electrical pulses corresponding to photo-detection events. It was predicted in 1984 on the basis of Quantum Optics and verified

Mark C. Booth, Mete Atature, Giovanni Di Giuseppe, Alexander V. Sergienko

The conditions required for spontaneous parametric down-conversion in a waveguide with periodic nonlinearity in the presence of an unguided pump field are established. Control of the periodic nonlinearity and the physical properties of the waveguide permits the quasi-phase matching equations that describe counter-propagating guided signal and idler beams to

Uwe Schwengelbeck

The time-dependent quantum system of two laser-driven electrons in a harmonic oscillator potential is analysed, taking into account the repulsive Coulomb interaction between both particles. The Schrodinger equation of the two-particle system is shown to be analytically soluble in case of arbitrary laser frequencies and individual oscillator frequencies, defi

Fabrizio Cametti, Carlo Presilla

By using numerical and semiclassical methods, we evaluate the quantum breaking, or Ehrenfest time for a wave packet localized around classical equilibrium points of autonomous one-dimensional systems with polynomial potentials. We find that the Ehrenfest time diverges logarithmically with the inverse of the Planck constant whenever the equilibrium point is e

H. M. Wiseman, Stefano Mancini, Jin Wang

We compare two different approaches to the control of the dynamics of a continuously monitored open quantum system. The first is Markovian feedback as introduced in quantum optics by Wiseman and Milburn [Phys. Rev. Lett. {\bf 70}, 548 (1993)]. The second is feedback based on an estimate of the system state, developed recently by Doherty {\em et al.} [Phys. R

Ar. Belkov

The paper is devoted to the method for 3D reconstruction of the straight tracks in the tracking system consisting of the drift-chamber stereo layers. The method is based on the Hough-transform approach - the discrete case of more general Radon transform - and takes into account both coordinates of the hit wires and drift distances not only for the measuremen

S. V. Nedea, A. P. J. Jansen, J. J. Lukkien, P. A. J. Hilbers

We have used Monte-Carlo methods and analytical techniques to investigate the influence of the characteristic parameters, such as pipe length, diffusion, adsorption, desorption and reaction rate constants on the steady-state properties of Single-File Systems with a reaction. We looked at cases when all the sites are reactive and when only some of them are re

Joel Lepak, M. Crescimanno

We report on a very simple and inexpensive method for determining the speed of an electrical wave in a transmission line. The method consists of analyzing the roundtrip time for ethernet packets between two computers. It involves minimal construction, straightforward mathematics and displays the usefulness of stochastic resonance in signal recovery. Using ba

C. Fuchs, Amand Faessler, S. El-Basaouny, K. Shekhter

The dependence of K+ production on the nuclear equation of state is investigated in heavy ion collisions. An increase of the excitation function of K+ multiplicities obtained in heavy (Au+Au) over light (C+C) systems when going far below threshold which has been observed by the KaoS Collaboration strongly favours a soft equation of state. This observation ho

P. Bozek

Symmetric nuclear matter is studied in the self-consistent, in-medium $T$-matrix approach. One-body spectral function, optical potential, and scattering width are calculated. Properties of quasi-particle excitations at the Fermi surface are discussed. Dispersive self-energies are dominated by contributions from the $^1S_0$, $3S_1-^3D_1$, and $^3P_1$ partial

A. Dobrowolski, K. Pomorski, J. Bartel

The nuclear binding energies for 28 nuclei including several isotopic chains with masses ranging from A=64 to A=226 were evaluated using the Skyrme effective nucleon-nucleon interaction and the Extended Thomas-Fermi approximation. The neutron and proton density distributions are assumed in the form of Fermi functions the parameters of which are determined so

M. Rousseau, C. Beck, C. Bhattacharya, V. Rauch

The possible occurence of highly deformed configurations in the $^{40}$Ca di-nuclear system formed in the $^{28}$Si + $^{12}$C reaction is investigated by analyzing the spectra of emitted light charged particles. Both inclusive and exclusive measurements of the heavy fragments (A $\geq$ 10) and their associated light charged particles (protons and $α$ partic

Zhijun Qiao, Cewen Cao, Walter Strampp

This paper deals with the category of nonlinear evolution equations (NLEEs) associated with the spectral problem and provides an approach for constructing their algebraic structure and $r$-matrix. First we introduce the category of NLEEs, which composes of various positive order and negative order hierarchies of NLEEs both integrable and non-integrable. The

Zhijun Qiao

The purpose of this paper is to develop the negative order MKdV hierarchy and to present a new related integrable Neumann-like Hamiltonian flow from the view point of inverse recursion operator and constraint method. The whole MKdV hierarchy both positive and negative is generated by the kernel elements of Lenard&#39;s operators pair and recursion operator.

Jordan G. Brankov

Finite-size scaling expressions for the current near the continuous phase transition, and for the local density near the first-order transition, are found in the steady state of the one-dimensional fully asymmetric simple-exclusion process (FASEP) with open boundaries and discrete-time dynamics. The corresponding finite-size scaling variables are identified

R. Matthes, O. Richter, G. Rudolph

Following ideas of Connes and Moscovici, we describe two spectral triples related to the Kronecker foliation, whose generalized Dirac operators are related to first and second order signature operators. We also consider the corresponding differential calculi $Ω_D$, which are drastically different in the two cases. As a side-remark, we give a description of a

J. Damek

The standard concept of scaling limits of distributions on manifolds is reformulated, and then a new framework for scaling at boundary points is provided. Next, we introduce a class of so-called L1 - KMS states, which is subsequently fully characterized for the Rindler wedge. Using these tools, we compute rigorously the scaling limit of the regular KMS state

Horng-Tzer Yau

We prove that the diffusion coefficient for the two dimensional asymmetric simple exclusion process diverges as $(\log t)^{2/3}$ to the leading order. The method applies to nearest and non-nearest neighbor asymmetric simple exclusion processes.

Andreas Gathmann

Given a general plane curve Y of degree d, we compute the number n_d of irreducible plane conics that are 5-fold tangent to Y. This problem has been studied before by Vainsencher using classical methods, but it could not be solved there because the calculations received too many non-enumerative correction terms that could not be analyzed. In our current appr

Dan Margalit

We show that the automorphism group of the complex of pants decompositions for a surface is isomorphic to the mapping class group for that surface.

C. Dong, G. Mason

We establish that the Lie algebra of weight one states in a (strongly) rational vertex operator algebra is reductive, and that its Lie rank is bounded above by the effective central charge. We show that lattice vertex operator algebras may be characterized by the equalities of the effective central charge, the Lie rank and the central charge, and in particul

C. Landim, J. Quastel, M. Salmhofer, H. T. Yau

We prove that the diffusion coefficient for the asymmetric exclusion process diverges at least as fast as $t^{1/4}$ in dimension $d=1$ and $(\log t)^{1/2}$ in $d=2$. The method applies to nearest and non-nearest neighbor asymmetric exclusion processes.

Joerg Schuermann

Using the index theorem of Dubson, Le, Ginsburg and Sabbah for the vanishing cycle functor, we give a short proof of formula of Brasselet, Le and Seade for the Euler obstruction.

Michael Soltys

We present a combinatorial interpretation of Berkowitz&#39;s algorithm. Berkowitz&#39;s algorithm is the fastest known parallel algorithm for computing the characteristic polynomial of a matrix. Our combinatorial interpretation is based on ``loop covers&#39;&#39; introduced by Valiant, and ``clow sequences.&#39;&#39; Clow sequences turn out to capture very s

Yuly Billig

We construct vertex operator representations for the full (N+1)-toroidal Lie algebra g. We associate with g a toroidal vertex operator algebra, which is a tensor product of an affine VOA, a sub-VOA of a hyperbolic lattice VOA, affine sl(N) VOA and a twisted Heisenberg-Virasoro VOA. The modules for the toroidal VOA are also modules for the toroidal Lie algebr

Panos Papasoglu

It is a consequence of the theorem of Stallings on groups with many ends that splittings over finite groups are preserved by quasi-isometries. In this paper we use asymptotic topology to show that group splittings are preserved by quasi-isometries in many cases. Roughly speaking we show that splittings are preserved under quasi-isometries when the vertex gro

Everett W. Howe

We prove that if q is a power of an odd prime then there is no genus-2 curve over F_q whose Jacobian has characteristic polynomial of Frobenius equal to x^4 + (2-2q)x^2 + q^2. Our proof uses the Brauer relations in a biquadratic extension of Q to show that every principally polarized abelian surface over F_q with the given characteristic polynomial splits ov

Mark W. Meckes

We describe in detail a general scheme for embedding several BPS monopoles into a theory with a larger gauge group, which generalizes embeddings of SU(2) monopoles discussed by several authors. This construction is applied to obtain explicit fields for monopoles with several charge configurations in the SU(5)\to [SU(3)\times SU(2)\times U(1)]/Z_6 model.

Klaus Behrndt, Mirjam Cvetic

Within D=5 N=2 gauged supergravity coupled to hypermultiplets we derive consistency conditions for BPS domain walls with constant negative curvature on the wall. For such wall solutions to exist, the covariant derivative of the projector, governing the constraint on the Killing spinor, has to be non-zero and proportional to the cosmological constant on the d

Donam Youm

We generalize the results of hep-th/0008140 to the case of the (n+1)-dimensional closed FRW universe satisfying a general equation of state of the form p=wρ. We find that the entropy of the universe can no longer be expressed in a form similar to the Cardy formula, when w\neq 1/n. As a result, in general the entropy formula does not coincide with the Friedma

Victor O. Rivelles

It is well known that the classical equations of motion of Maxwell and Born-Infeld theories are invariant under a duality symmetry acting on the field strengths. We review the implementation of the SL(2,Z) duality in these theories as linear but non-local transformations of the potentials.

Edi Gava, Amine B. Hammou, Jose F. Morales, Kumar S. Narain

We study the spectra of BPS excitations of D1D5 bound states in a class of free orbifolds/orientifolds of type IIB theory and its dual descriptions in terms of chiral primaries of the corresponding $AdS_3$ supergravities.

Jose B. Almeida

4-dimensional optics is here introduced axiomatically as the space that supports a Universal wave equation which is applied to the postulated Higgs field. Self-guiding of this field is shown to produce all the modes necessary to provide explanations for the known elementary particles. Forces are shown to appear as evanescent fields due to waveguiding of the

Hisashi Echigoya, Tadashi Miyazaki, Tomohiko Shibuya

With two typical parent actions we have two kinds of dual worlds: i) one of which contains an electric as well as magnetic current, and ii) the other contains (generalized) Chern-Simons terms. All these fields are defined on a curved spacetime of arbitrary (odd) dimensions. A new form of gauge transformations is introduced and plays an essential role in defi

Y. S. Kim

There are gauge-transformation operators applicable to massless spin-1/2 particles within the little-group framework of internal space-time symmetries of massive and massless particles. It is shown that two of the $SL(2,c)$ spinors are invariant under gauge transformations while the remaining two are not. The Dirac equation contains only the gauge-invariant

A. J. M. Medved

The microscopic origin of black hole entropy remains one of the more intriguing open questions in theoretical physics. A subplot in this drama is the renowned Cardy-Verlinde formula, which uses two-dimensional conformal formalism to explain the entropy of an arbitrary-dimensional black hole. In this paper, by exploiting the AdS/CFT and black hole-string dual

Tomohiko Takahashi, Seriko Tanimoto

This paper has been withdrawn by the authors, due a crucial error in Sec. 3.

A. L. Kagan

Three new results are discussed: (a) A non-vanishing amplitude for the `wrong sign{&#39;} kaon decay $B \to J/Ψ\bar{K}$ or its CP conjugate is shown to be a necessary condition for obtaining different CP asymmetries in $B \to J/ΨK_{S,L}$. A significant effect would require a scale of new physics far below the weak scale, all but ruling out this possibility.

R. J. Fries

This talk serves as an introduction to higher twist effects in nuclei. We want to discuss how perturbative QCD can be applied to processes involving heavy nuclei by taking into account multiple scattering.

Thomas Hambye

We present a determination of the neutrino mass matrix which holds for values of the neutrinoless double beta decay effective mass m_{ee} larger than the neutrino mass differences. We find eight possible solutions and discuss for each one the corresponding neutrino mass eigenvalues and zero texture. A minimal structure of the perturbations to add to these ze

G. Duplancic, B. Nizic

The IR finite one-loop box scalar integral with massless internal lines has been recalculated. The result is very compact, simple and valid for arbitrary values of the relevant kinematic variables. It is given in terms of only two dilogarithms and a few logarithms, all of very simple arguments.

P. Colangelo, F. De Fazio

We analyze the decay modes $B^0 \to D^{*-} D^0 K^+$ and $B^0 \to D^{*-} D^{*0} K^+$ and, using the available experimental data, we find bounds for the constants g and h describing the strong coupling of heavy mesons to light pseudoscalar mesons. Both the decay channels are dominated by broad L=1 charm resonances; the dominance is effective also in $B^0 \to D

R. Bruneliere, A. Denner, S. Dittmaier, S. Jadach

We discuss theoretical uncertainties of the distribution in the cosine of the W polar angle projected into a measurement of the anomalous triple gauge-boson coupling λ=λ_γ=λ_Z at LEP2 energies for the tandem of the Monte Carlo event generators KoralW and YFSWW3 and for the Monte Carlo event generator RacoonWW. Exploiting numerical results of these programs a

N. N. Achasov

Based on gauge invariance, we show that the new threshold phenomenon is discovered in the ϕradiative decays ϕ\toγa0\toγ\pi0ηand ϕ\toγf0\toγ\pi0\pi0. This enables to conclude that production of the lightest scalar mesons a0(980) and f0(980) in these decays is caused by the four-quark transitions, resulting in strong restrictions on the large Nc expansions of

James M. Cline

I review the status of the strength of the electroweak phase transition, and electroweak baryogenesis in the Minimal Supersymmetric Standard Model (work done with K. Kainulainen and M. Joyce). The emphasis is on new brane-inspired ideas about electroweak baryogenesis, and improvements in the semiclassical treatment of CP violation at a first order electrowea

J. M. Link

A high statistics measurement of the Lambdac+ lifetime from the Fermilab fixed-target FOCUS photoproduction experiment is presented. We describe the analysis technique with particular attention to the determination of the systematic uncertainty. The measured value of 204.6 +/- 3.4 (stat.) +/- 2.5 (syst.) fs from 8034 +/- 122 Lambdac -> pKpi decays represents

Giovanni Imponente, Giovanni Montani

We provide a Hamiltonian analysis of the Mixmaster Universe dynamics on the base of a standard Arnowitt-Deser-Misner Hamiltonian approach, showing the covariant nature of its chaotic behaviour with respect to the choice of any time variable, from the point of view either of the dynamical systems theory, either of the statistical mechanics one.

Giovanni Imponente, Giovanni Montani

This paper provides a review of some recent issues on the Mixmaster dynamics concerning the features of its stochasticity. After a description of the geometrical structure characterizing the homogeneous cosmological models in the Bianchi classification and the Belinsky-Khalatnikov-Lifshitz piecewise representation of the types VIII and IX oscillatory regime,

M. E. X. Guimaraes, L. P. Colatto, F. B. Tourinho

In the paper published in Phys. Lett. A245} (1998) 31, Barros and Romero demonstrated that, in the weak-field approximation, solutions to the Brans-Dicke equations are related to the solutions of General Relativity for the same matter distributions. In the present work, we enphasize this result and we extend it to for generalized scalar-tensor theories in wh

Xiaoning Wu, Han-Ying Guo, Chao-Guang Huang, Ke Wu

The Noether current and its variation relation with respect to diffeomorphism invariance of gravitational theories have been derived from the horizontal variation and vertical-horizontal bi-variation of the Lagrangian, respectively. For Einstein&#39;s GR in the stationary, axisymmetric black holes, the mass formula in vacuum can be derived from this Noether

Israel Quiros

Pushing forward the similitudes between the gravitational collapse and the expansion of the universe (in the reversed sense of time), it should be expected that, during the collapse, eventually, a spacetime domain would be reached where attained energy scales are very high. In consequence some of the compactified extra dimensions may be decompactified and so

Marcelo S. Berman, Luis A. Trevisan

By employing Dirac LNH, and a further generalization by Berman (GLNH), we estimate how should vary the total number of nucleons, the energy density, Newton Gravitational constant, the cosmological constant, the magnetic permeability and electric permitivity, of the Universe,in order to account for the experimentally observed time variation of the fine struct

Marcelo S. Berman, Luis A. Trevisan

We determine a cosmological model that include a positive acceleration of the Universe and a time decreasing fine structure constant. The present day deceleration parameter is estimated by us, according to our model and the available experimental data .

James H. Andrews

The semantics of the Prolog ``cut&#39;&#39; construct is explored in the context of some desirable properties of logic programming systems, referred to as the witness properties. The witness properties concern the operational consistency of responses to queries. A generalization of Prolog with negation as failure and cut is described, and shown not to have t

Claudia Bungaro, K. M. Rabe

Ab initio phonon calculations for the nonpolar reference structures of the (001), (110), and (111) PbZrO_3/PbTiO_3 [1:1] superlattices are presented. The unstable polar modes in the tetragonal (001) and (110) structures are confined in either the Ti- or the Zr-centered layers and display two-mode behavior, while in the cubic (111) case one-mode behavior is o

A. Yu. Galkin, B. A. Ivanov

Abrikosov vortex lattice dynamics in a superconductor with weak defects is studied taking into account gyroscopic (Hall) properties. It is demonstrated that interaction of the moving lattice with weak defects results in appearance of the additional drag force, $F$, which is $F(V)\propto \sqrt V$ at small velocities, while at high velocities $F(V)\propto 1/\s

Jose A. Miranda

We report analytical results for the development of the viscous fingering instability in a cylindrical Hele-Shaw cell of radius a and thickness b. We derive a generalized version of Darcy&#39;s law in such cylindrical background, and find it recovers the usual Darcy&#39;s law for flow in flat, rectangular cells, with corrections of higher order in b/a. We fo

Ines Samengo, Alessandro Treves

The capacity with which a system of independent neuron-like units represents a given set of stimuli is studied by calculating the mutual information between the stimuli and the neural responses. Both discrete noiseless and continuous noisy neurons are analyzed. In both cases, the information grows monotonically with the number of neurons considered. Under th

M. Ausloos, K. Ivanova

Classical technical analysis methods of stock evolution are recalled, i.e. the notion of moving averages and momentum indicators. The moving averages lead to define death and gold crosses, resistance and support lines. Momentum indicators lead the price trend, thus give signals before the price trend turns over. The classical technical analysis investment st

Frieder Kalisch, Daniel Braak

We calculate the exact density of states (DOS) for the three classical and two non-classical Random Matrix Ensembles for finite matrix size N using supersymmetric integrals. The 1/N-Expansion yields already in lowest order good approximations to the exact result even for small values of N~5. We conjecture a connection between the N-dependence of the oscillat

D. Schmalfuss, P. Tomczak, J. Schulenburg, J. Richter

A linear spin-wave approach, a variational method and exact diagonlization are used to investigate the magnetic long-range order (LRO) of the spin-1/2 Heisenberg antiferromagnet on a two-dimensional 1/7-depleted triangular (maple leaf) lattice consisting of triangles and hexagons only. This lattice has z=5 nearest neighbors and its coordination number z is t

Enrico Carlon, Andrzej Drzewinski, J. M. J. van Leeuwen

We investigate the Rubinstein-Duke model for polymer reptation by means of density-matrix renormalization group techniques both in absence and presence of a driving field. In the former case the renewal time τand the diffusion coefficient D are calculated for chains up to N=150 reptons and their scaling behavior in N is analyzed. Both quantities scale as pow

P. W. Brouwer, E. Racine, A. Furusaki, Y. Hatsugai

If the number of lattice sites is odd, a quantum particle hopping on a bipartite lattice with random hopping between the two sublattices only is guaranteed to have an eigenstate at zero energy. We show that the localization length of this eigenstate depends strongly on the boundaries of the lattice, and can take values anywhere between the mean free path and

H. Kotegawa, K. Ishida, Y. Kitaoka, T. Muranaka

We report $^{11}$B-NMR study on Al-doped MgB$_2$ that addresses a possible mechanism for a high superconducting (SC) transition temperature ($T_c$) of $\sim 40$ K in recently discovered MgB$_2$. The result of nuclear spin lattice relaxation rate $1/T_1$ in the SC state revealed that the size in the SC gap is not changed by substituting Al for Mg. The reducti

S. M. Cronenwett, H. J. Lynch, D. Goldhaber-Gordon, L. P. Kouwenhoven

Besides the usual conductance plateaus at multiples of 2e2/h, quantum point contacts typically show an extra plateau at ~ 0.7(2e2/h), believed to arise from electron-electron interactions that prohibit the two spin channels from being simultaneously occupied. We present evidence that the disappearance of the 0.7 structure at very low temperature signals the