October 2000 arXiv papers

J. L. Hewett, F. J. Petriello, T. G. Rizzo

Recent theoretical results have demonstrated that non-commutative geometries naturally appear within the context of string/M-theory. One consequence of this possibility is that QED takes on a non-abelian nature due to the introduction of 3- and 4-point functions. In addition, each QED vertex acquires a momentum dependent phase factor. We parameterize the eff

D. O. Caldwell, R. N. Mohapatra, S. J. Yellin

Solar, atmospheric and LSND neutrino oscillation results require a light sterile neutrino, $ν_B$, which can exist in the bulk of extra dimensions. Solar $ν_e$, confined to the brane, can oscillate in the vacuum to the zero mode of $ν_B$ and via successive MSW transitions to Kaluza-Klein states of $ν_B$. This new way to fit solar data is provided by both low

M. Carena, J. S. Conway, H. E. Haber, J. D. Hobbs

This report presents the theoretical analysis relevant for Higgs physics at the upgraded Tevatron collider and documents the Higgs Working Group simulations to estimate the discovery reach in Run 2 for the Standard Model and MSSM Higgs bosons. Based on a simple detector simulation, we have determined the integrated luminosity necessary to discover the SM Hig

Ph. de Forcrand, M. Pepe

We exhibit the connection between local gauge singularities in the Laplacian gauge and topological charge, which opens the possibility of studying instanton excitations without cooling. We describe our version of Laplacian gauge-fixing for SU(N).

G. Akemann, E. Kanzieper

The microscopic spectral eigenvalue correlations of QCD Dirac operators in the presence of dynamical fermions are calculated within the framework of Random Matrix Theory (RMT). Our approach treats the low--energy correlation functions of all three chiral symmetry breaking patterns (labeled by the Dyson index $β=1,2$ and 4) on the same footing, offering a uni

Lee Lindblom, Joel E. Tohline, Michele Vallisneri

The evolution of a neutron-star r-mode driven unstable by gravitational radiation (GR) is studied here using numerical solutions of the full non-linear fluid equations. The amplitude of the mode grows to order unity before strong shocks develop which quickly damp the mode. In this simulation the star loses about 40% of its initial angular momentum and 50% of

David Bessis

Empirical properties of generating systems for complex reflection groups and their braid groups have been observed by Orlik-Solomon and Broué-Malle-Rouquier, using Shephard-Todd classification. We give a general existence result for presentations of braid groups, which partially explains and generalizes the known empirical properties. Our approach is invaria

D. Schmeltzer

We show that the macroscopic current and charge can be formulated as a Quantum Mechanical zero mode problem. We find that the current is given by the velocity operator of a particle restricted to move around a circle. As an explicit example we investigate a Luttinger liquid of length $L$ which is perturbed by a time dependent impurity. Using the statistical

Christian Korff

A new set of exact scattering matrices in 1+1 dimensions is proposed by solving the bootstrap equations. Extending earlier constructions of colour valued scattering matrices this new set has its colour structure associated to non simply-laced Lie algebras. This in particular leads to a coupling of different affine Toda models whose fusing structure has to be

D. A. Brown, P. Danielewicz

We examine the possibility of extracting non-Gaussian sources from two-particle correlations in heavy-ion reactions. Non-Gaussian sources have been predicted in a variety of model calculations and may have been seen in various like-meson pair correlations. As a tool for this investigation, we have developed an improved imaging method that relies on a Basis s

M. Della Morte, R. Frezzotti, J. Heitger, S. Sint

We present a scaling study of lattice QCD with O(a) improved Wilson fermions and a chirally twisted mass term. In order to get precise results with a moderate computational effort, we have considered a system of physical size of 0.75^3 * 1.5 fm^4 with Schroedinger functional boundary conditions in the quenched approximation. Looking at meson observables in t

A. Chuvakin, J. Smith, B. W. Harris

Data for D*(2010) meson electroproduction in the range 10 < Q2 < 1350 GeV^2 has recently been presented by the ZEUS collaboration at HERA. We use these results together with previously published data for Q2 > 1 GeV^2 to test whether one can distinguish between different theoretical schemes for charm quark electroproduction. We find that up to the largest Q2

J. Bartels, H. Kowalski

We discuss HERA data on the high energy behavior of the total gamma*p cross section and on diffraction in deep inelastic scattering. We outline their novelty in comparison with diffraction in high energy hadron hadron scattering. As a physical picture, we propose an interpretation in terms of QCD radiation at small and large distances: a careful study of the

Anton Kapustin, Dmitri Orlov

A vertex algebra is an algebraic counterpart of a two-dimensional conformal field theory. We give a new definition of a vertex algebra which includes chiral algebras as a special case, but allows for fields which are neither meromorphic nor anti-meromorphic. To any complex torus equipped with a flat Kahler metric and a closed 2-form we associate an N=2 super

Ken Kashima

We consider the effective action of M-theory compactified on a S^1/Z_2 orbifold with R^2 interaction in the Gauss-Bonnet combination. We derive equations of motion with source terms arising from the Gauss-Bonnet terms and find the M2-brane solution up to order κ^{2/3}. It receives a correction which depends on the orbifold coordinate in the same form as the

JLQCD Collaboration, N. Yamada, S. Aoki, R. Burkhalter

We present our recent results for the B-parameters, which parameterize the ΔB=2 transition amplitudes. Calculations are made in quenched QCD at β=5.7, 5.9, and 6.1, using NRQCD for heavy quark and the $O(a)$-improved action for light quark. The operators are perturbatively renormalized including corrections of O(α_s/am_Q). We examine scaling behavior of the

Daniel A. Stariolo

We show results of simulations of a weakly driven four dimensional Edwards- Anderson spin glass, which presents clear signatures of dynamical ultrametricity at low temperatures. The presence of a hierarchical organization of time scales is evident from the appearance of a triangular relation between correlations at three characteristic long times in the asym

Y. G. Yi

An electron may interact with itself through the vacuum polarization induced in the vacuum electrons due to the electron.

Th. Boller, R. Keil, J. Truemper, P. T. O&#39;Brien

We have analyzed the timing properties of the Narrow-line Seyfert 1 galaxy Mrk 766 observed with XMM-Newton during the PV phase. The source intensity changes by a factor of 1.3 over the 29,000 second observation. If the soft excess is modeled by a black body component, as indicated by the EPIC pn data, the luminosity of the black body component scales with i

Ozay Gurtug, Mustafa Halilsoy

Single pulse of null dust and colliding null dusts both transform a regular horizon into a space-like singularity in the space of colliding waves. The local isometry between such space-times and black holes extrapolates these results to the realm of black holes. However, inclusion of particular scalar fields instead of null dusts creates null singularities r

Yuri I. Izotov, Daniel Schaerer, Corinne Charbonnel

The similarity between observed velocity structures of Al III and singly ionized species in damped Lyman-alpha systems (DLAs) suggests the presence of ionized gas in the regions where most metal absorption lines are formed. A simplified model consisting of Region 1) a plane-parallel ionization bounded region illuminated by an internal radiation field, and Re

R. S. Thorne, R. G. Roberts

The Thorne-Roberts variable flavour number scheme (VFNS) for heavy quarks is presented in detail for the specific case of charged current DIS. As in neutral current DIS this provides a smooth extrapolation from the fixed flavour number scheme (FFNS) appropriate at low $Q^2$ to the zero-mass variable flavour number scheme (ZM-VFNS) appropriate as $Q^2 \to \in

R. Mélin

It is demonstrated that non local Cooper pairs can propagate in ferromagnetic electrodes having an opposite spin orientation. In the presence of such crossed correlations, the superconducting gap is found to depend explicitly on the relative orientation of the ferromagnetic electrodes. Non local Cooper pairs can in principle be probed with dc-transport. With

Hideo Nakajima, Sadataka Furui, Azusa Yamaguchi

Critical conjectures on confinement in the Landau gauge is numerically tested in focus to Gribov copy effects. One of the subjects is of the Kugo-Ojima confinement criterion and the other is of various viewpoints in the Gribov-Zwanziger theory. We use the smearing gauge as a reference gauge free of Gribov copy, and performed three types of simulations, log U

K. Ziegler, W. A. Atkinson, P. J. Hirschfeld

We calculate the density of states (DOS) in a clean mesoscopic d-wave superconducting quantum wire, i.e. a sample of infinite length but finite width $N$. For open boundary conditions, the DOS at zero energy is found to be zero if $N$ is even, and nonzero if $N$ is odd. At finite chemical potential, all chains are gapped but the qualtitative differences betw

R. Durrer, M. Kunz, A. Melchiorri

During the last years it has become clear that global O(N) defects and U(1) cosmic strings do not lead to the pronounced first acoustic peak in the power spectrum of anisotropies of the cosmic microwave background which has recently been observed to high accuracy. Inflationary models cannot easily accommodate the low second peak indicated by the data. Here w

A. P. B. Scarpelli, M. Sampaio, M. C. Nemes

We extend an implicit regularization scheme to be applicable in the $n$-dimensional space-time. Within this scheme divergences involving parity violating objects can be consistently treated without recoursing to dimensional continuation. Special attention is paid to differences between integrals of the same degree of divergence, typical of one loop calculati

M. A. Olalla Acosta

In this paper we study the rank one discrete valuations of $k((X_1,... ,X_n))$ whose center in $k\lcor\X\rcor$ is the maximal ideal $(\X)$. In sections 2 to 6 we give a construction of a system of parametric equations describing such valuations. This amounts to finding a parameter and a field of coefficients. We devote section 2 to finding an element of valu

S. J. Brodsky, E. Chudakov, P. Hoyer, J. M. Laget

Charm and bottom production near threshold is sensitive to the multi-quark, gluonic, and hidden-color correlations of hadronic and nuclear wavefunctions in QCD since all of the target&#39;s constituents must act coherently within the small interaction volume of the heavy quark production subprocess. Although such multi-parton subprocess cross sections are su

Hiroyuki Takata

We present a scenario for deriving Maxwell theory from IIB matrix model. Four dimensional spacetime and theories on it relate different dimensional ones by applying appropriate limits of the backgrounds of matrix model. It is understood by looking at open strings bits as bi-local fields on the spacetime, which are decoupled from the bulk in the limits. The o

De-Min Li, Hong Yu, Qi-Xing Shen

In the $f_2(1270)-f^\prime_2(1525)$ mixing framework, the isoscalar singlet-octet mixing angle for 1$^3P_2$ tensor nonet is determined to be the value of $27.5^\circ$ and the decays of the two states are investigated. Comparing the predicted results of the decays of the two states with the available experimental data, we find that the predicted results are i

L. Giusti, M. L. Paciello, S. Petrarca, C. Rebbi

We illustrate preliminary results on the gluon propagator computed in generic covariant lattice gauges in the quenched approximation with the Wilson action. We have applied a recently proposed procedure to fix a generic covariant gauge on the lattice. We make a comparison among results obtained at two different values of the gauge parameter and in the standa

PACS Collaboration, A. Ali Khan, S. Aoki, Y. Aoki

We report on a calculation of $B_K$ with domain wall fermion action in quenched QCD. Simulations are made with a renormalization group improved gauge action at $β=2.6$ and 2.9 corresponding to $a^{-1}\approx 2$GeV and 3GeV. Effects due to finite fifth dimensional size $N_5$ and finite spatial size $N_σ$ are examined in detail. Matching to the continuum opera

H. Hatanaka, S. Matsumoto, K. Ohnishi, M. Sakamoto

We study scalar field theories on M^{D-1} \otimes S^1, which allow to impose twisted boundary conditions for the S^1 direction, in detail and report several interesting properties overlooked so far. One of characteristic features is the appearance of critical radii of the circle S^1. A phase transition can occur at the classical level or can be caused by qua

Bruce A. Bassett, Giuseppe Pollifrone, Shinji Tsujikawa, Fermin Viniegra

We study the amplification of large-scale magnetic fields during preheating and inflation in several different models. Preheating can resonantly amplify seed fields on cosmological scales. In the presence of conductivity, however, the effect of resonance is typically weakened while the amplitude of produced magnetic fields depends sensitively on the evolutio

Jorgen Rasmussen, Mark A. Walton

Information on su(N) tensor product multiplicities is neatly encoded in Berenstein-Zelevinsky triangles. Here we study a generalisation of these triangles by allowing negative as well as non-negative integer entries. For a fixed triple product of weights, these generalised Berenstein-Zelevinsky triangles span a lattice in which one may move by adding integer

Stephen J. Bigelow, Ryan D. Budney

In this paper we construct a faithful representation of the mapping class group of the genus two surface into a group of matrices over the complex numbers. Our starting point is the Lawrence-Krammer representation of the braid group B_n, which was shown to be faithful by Bigelow and Krammer. We obtain a faithful representation of the mapping class group of t

Rodolfo A. Diaz, R. Martinez, J. -Alexis Rodriguez

Current experimental data from the $g-2$ muon factor, seems to show the necessity of physics beyond the Standard Model (SM), since the difference between SM and experimental predictions is 2.6$σ$. In the framework of the General Two Higgs Doublet Model (2HDM), we calculate the muon anomalous magnetic moment to get lower and upper bounds for the Flavour Chang

Ashwin Nayak, Ashvin Vishwanath

Motivated by the immense success of random walk and Markov chain methods in the design of classical algorithms, we consider_quantum_ walks on graphs. We analyse in detail the behaviour of unbiased quantum walk on the line, with the example of a typical walk, the ``Hadamard walk&#39;&#39;. We show that after t time steps, the probability distribution on the l

Guido Berlin, J. Aliaga

In this paper we study a two-photon time-dependent Jaynes-Cummings model interacting with a Kerr-like medium. We assumed that the electromagnetic field is in different states such as coherent, squeezed vacuum and pair coherent, and that the atom is initially in the excited state. We studied the temporal evolution of the population of the excited level, and t

P. Busch

This is an essay review of the book by D. Home: &#34;Conceptual Foundations of Quantum Physics: An Overview from Modern Perspectives&#34; (New York: Plenum Press, 1997), xvii+386 pp., ISBN 0-306-45660-5.

Anthony Chefles

There are fundamental limits to the accuracy with which one can determine the state of a quantum system. I give an overview of the main approaches to quantum state discrimination. Several strategies exist. In quantum hypothesis testing, a quantum system is prepared in a member of a known, finite set of states, and the aim is to guess which one with the minim

C. Trump, D. Bruss, M. Lewenstein

We calculate the highest possible information gain in a measurement of entangled states when employing a beamsplitter. The result is used to evaluate the fidelity, averaged over all unknown inputs, in a realistic teleportation protocol that takes account of the imperfect detection of Bell states. Finally, we introduce a probabilistic teleportation scheme, wh

J. Mueller-Quade, H. Imai

Due to the impossibility results of Mayers and Lo/Chau it is generally thought that a quantum channel is cryptographically strictly weaker than oblivious transfer. In this paper we prove that in a three party scenario a quantum channel can be strictly stronger than oblivious transfer. With the protocol introduced in this paper we can completely classify the

Hao-Sheng Zeng, Xi-Wen Zhu, Ke-Lin Gao

We propose a scheme to generate a superposition with arbitrary coefficients on a line in phase space for the center-of-mass vibrational mode of N ions by means of isolating all other spectator vibrational modes from the center-of-mass mode. It can be viewed as the generation of previous methods for preparing motional states of one ion. For large number of io

Ioannis Raptis, Roman R. Zapatrin

Using the leading vector method, we show that any vector $h\in(C^2)^{\otimes l}$ can be decomposed as a sum of at most (and at least in the generic case) $2^l-l$ product vectors using local bitwise unitary transformations. The method is based on representing the vectors by chains of appropriate simplicial complex. This generalizes the Scmidt decomposition of

Anirvan Mayukh Sengupta, Partha Pratim Mitra

We study memoryless, discrete time, matrix channels with additive white Gaussian noise and input power constraints of the form $Y_i = \sum_j H_{ij} X_j + Z_i$, where $Y_i$ ,$X_j$ and $Z_i$ are complex, $i=1..m$, $j=1..n$, and $H$ is a complex $m\times n$ matrix with some degree of randomness in its entries. The additive Gaussian noise vector is assumed to ha

A. Dumitru, J. Brachmann, E. S. Fraga, W. Greiner

A generic property of a first-order phase transition in equilibrium, and in the limit of large entropy per unit of conserved charge, is the smallness of the isentropic speed of sound in the ``mixed phase&#39;&#39;. A specific prediction is that this should lead to a non-isotropic momentum distribution of nucleons in the reaction plane (for energies around 40

S. Stoica, H. V. Klapdor-Kleingrothaus

Double-beta decay matrix elements (ME) for $^{76}Ge$ are calculated with different quasi random phase approximation (QRPA)-based methods. First, the ME for the two-neutrino mode are computed using two choices for the single particle (s.p.) basis: i) $2-4\hbarω$ full shells and ii) $3-4\hbarω$ full shells. When calculated with the renormalized QRPA (RQRPA) an

Attila Csoto

We have localized several few-body resonances in light nuclei, using methods which can properly handle two- or three-body resonant states. Among other results, we predict the existence of a three-neutron resonance, small spin-orbit splittings between the low-lying states in He-5 and Li-5, the nonexistence of the soft dipole resonance in He-6, new 1+ states i

Jorgen Randrup

A practical quantum-field treatment is developed for systems endowed with an effective mass function depending on both space and time and a schematic application illustrates the quantitative importance of quantum fluctuations in the dynamics of disoriented chiral condensates.

Sven Soff, D. Zschiesche, M. Bleicher, C. Hartnack

The yields of strange particles are calculated with the UrQMD model for p,Pb(158 AGeV)Pb collisions and compared to experimental data. The yields are enhanced in central collisions if compared to proton induced or peripheral Pb+Pb collisions. The enhancement is due to secondary interactions. Nevertheless, only a reduction of the quark masses or equivalently

Th. Pospischil, P. Bartsch, D. Baumann, J. Bermuth

The recoil proton polarization has been measured in the p (\vec e,e&#39;\vec p) pi^0 reaction in parallel kinematics around W = 1232 MeV, Q^2 = 0.121 (GeV/c)^2 and epsilon = 0.718 using the polarized c.w. electron beam of the Mainz Microtron. Due to the spin precession in a magnetic spectrometer, all three proton polarization components P_x/P_e = (-11.4 \pm

B. V. Chirikov, O. V. Zhirov

Large entropy fluctuations in an equilibrium steady state of classical mechanics were studied in extensive numerical experiments on a simple 2--freedom strongly chaotic Hamiltonian model described by the modified Arnold cat map. The rise and fall of a large separated fluctuation was shown to be described by the (regular and stable) &#34;macroscopic&#34; kine

Andrey A. Sukhorukov, Yuri S. Kivshar

We analyze the existence and stability of nonlinear localized waves in a periodic medium described by the Kronig-Penney model with a nonlinear defect. We demonstrate the existence of a novel type of stable nonlinear band-gap localized states, and also reveal an important physical mechanism of the oscillatory wave instabilities associated with the band-gap re

L. A. Dickey

There are well-known constructions of integrable systems which are chains of infinitely many copies of the equations of the KP hierarchy ``glued&#39;&#39; together with some additional variables, e.g., the modified KP hierarchy. Another interpretation of the latter, in terms of infinite matrices, is called the 1-Toda lattice hierarchy. One way infinite reduc

Leonardo F. Guidi, Domingos H. U. Marchetti

We consider a quasilinear parabolic differential equation associated with the renormalization group transformation of the two-dimensional hierarchical Coulomb system in the limit as the size of the block L goes to 1. We show that the initial value problem is well defined in a suitable function space and the solution converges, as t goes to infinity, to one o

D. Bullock, C. Frohman, J. Kania-Bartoszynska

We prove that the Kauffman bracket skein algebra of a cylinder over a surface with boundary, defined over complex numbers, is isomorphic to the observables of an appropriate lattice gauge field theory.

Valeri A. Gritsenko, Viacheslav V. Nikulin

This is the announcement and partly the review of our results about classification of Lorentzian Kac-Moody algebras of the rank three. One of our results gives the classification of Lorentzian Kac-Moody algebras with denominator identity functions which are holomorphic reflective automorphic forms with respect to paramodular groups. Almost all of them were f

C. Frohman, J. Kania-Bartoszynska

We describe a topological ribbon Hopf algebra whose elements are sequences of matrices. The algebra is a quantum version of U(sl_2).

Cameron McA. Gordon, Ying-Qing Wu

We show that if a simple 3-manifold $M$ has two Dehn fillings at distance $Δ\geq 4$, each of which contains an essential annulus, then $M$ is one of three specific 2-component link exteriors in $S^3$. One of these has such a pair of annular fillings with $Δ= 5$, and the other two have pairs with $Δ= 4$.

Yi-Zhi Huang

For a finitely-generated vertex operator algebra of central charge c, a locally convex topological completion is constructed. We construct on the completion a structure of an algebra over the operad of the c/2-th power of the determinant line bundle over the moduli space of genus-zero Riemann surfaces with ordered analytically parametrized boundary component

Alex Clark

Generalizing a construction of A. Weil, we introduce a topological invariant for flows on compact, connected, finite dimensional, abelian, topological groups. We calculate this invariant for some examples and compare the invariant with other flow invariants.

Vyacheslav M. Futorny, Duncan J. Melville, Alexander N. Grishkov

Let g be an untwisted affine Kac-Moody algebra and M_J(lambda) a Verma-type module for g with J-highest integral weight lambda. We construct quantum Verma-type modules M_J^q(lambda) over the quantum group U_q(g), investigate their properties and show that M_J^q(lambda) is a true quantum deformation of M_J(ł) in the sense that the weight structure is preserve

F. Planas-Vilanova

In his paper &#34;Residues of a Pfaff system relative to an invariant subscheme&#34; in Trans. Amer. Math. Soc. 352, 2000, 4019-4035, F. Sancho de Salas defines the universal Koszul complex of a module $M$ over a sheaf of rings $\mathcal{O}$ as ${\rm Kos}(M)=Λ(M)\otimes_{\mathcal{O}}S(M)$, where $Λ(M)$ and $S(M)$ stand for the exterior and symmetric algebras

Anvar R. Mavlyutov

We study the B-model chiral ring of Calabi-Yau hypersurfaces in Batyrev&#39;s mirror construction. The main result is an explicit description of a subring of the chiral ring of semiample regular (transversal to torus orbits) Calabi-Yau hypersurfaces. This subring includes the marginal operators and contains all information about the correlation functions use

Igor Bayak

It is shown in what way monomial group connects Abelian group Z^{n} and total linear group GL(n). It is shown that any subgroup of Abelian group Z^{n} induces subgroup of monomial group $S_{2}\wr S_n}$, which in its turn induces corresponding subgroup of GL_{n}(R).

Eric Goles, Michel Morvan, Ha Duong Phan

In this paper, we study the dynamics of sand grains falling in sand piles. Usually sand piles are characterized by a decreasing integer partition and grain moves are described in terms of transitions between such partitions. We study here four main transition rules. The more classical one, introduced by Brylawski (1973) induces a lattice structure $L_B (n)$

Daniel Grieser

R. B. Melrose&#39;s b-calculus provides a framework for dealing with problems of partial differential equations that arise in singular or degenerate geometric situations. This article is a somewhat informal short course introducing many of the basic ideas of this world, assuming little more than a basic analysis and manifold background. As examples, classica

David Ananikian, Petr Kulish, Vladimir Lyakhovsky

Serious difficulties arise in the construction of chains of twists for symplectic Lie algebras. Applying the canonical chains of extended twists to deform the Hopf algebras U(sp(N)) one is forced to deal only with improper chains (induced by the U(sl(N)) subalgebras). In the present paper this problem is solved. For chains of regular injections the sets of m

Alexander Getmanenko

Families of translates and homothets of strictly convex curves are proven to possess Helly-type properties generalizing those of a circle. Weaker results are shown for arbitrary convex curves.

S. J. Colley, G. Kennedy

Given a flat, projective morphism $Y \to T$ from an equidimensional scheme to a nonsingular curve and a subscheme $Z$ of $Y$, we give conditions under which specialization of the Segre class $s(N_{Z}Y)$ of the normal cone of $Z$ in $Y$ implies flatness of the normal cone. We apply this result to study when the relative tangent star cone of a flat family is f

R. Skip Garibaldi

For G an almost simple simply connected algebraic group defined over a field F, Rost has shown that there exists a canonical map R_G: H^1(F, G) --> H^3(F, Q/Z(2)). This includes the Arason invariant for quadratic forms and Rost&#39;s mod 3 invariant for Albert algebras as special cases. We show that R_G has trivial kernel if G is quasi-split of type E_6 or E

Raimundas Vidunas

The well-known Kummer&#39;s formula evaluates the hypergeometric series 2F1(A,B;C;-1) when the relation B-A+C=1 holds. This paper deals with evaluation of 2F1(-1) series in the case when C-A+B is an integer. Such a series is expressed as a sum of two Γ-terms multiplied by terminating 3F2(1) series. A few such formulas were essentially known to Whipple in 192

Bernard de Wit

We discuss toroidal compactifications of maximal supergravity coupled to an extended configuration of BPS states which transform consistently under the U-duality group. Under certain conditions this leads to theories that live in more than eleven spacetime dimensions, with maximal supersymmetry but only partial Lorentz invariance. We demonstrate certain feat

K. Lechner, P. A. Marchetti

We analyse spin and statistics of quantum dyon fields, i.e. fields carrying both electric and magnetic charge, in 3+1 space-time dimensions. It has been shown long time ago that, at the quantum mechanical level, a composite dyon made out of a magnetic pole of charge g and a particle of electric charge e possesses half-integral spin and fermionic statistics,

Victor Kac, Jan Troost

We discuss the stability of vacua in two-dimensional gauge theory for any simple, simply connected gauge group. Making use of the representation of a vacuum in terms of a Wilson line at infinity, we determine which vacua are stable against pair production of heavy matter in the adjoint of the gauge group. By calculating correlators of Wilson loops, we reduce

Giampiero Esposito, Alexander Yu. Kamenshchik

A brief review is presented of motivations and results in one-loop supergravity on manifolds with boundary, whose consideration is suggested by quantum cosmology.

Hiroshi Ozaki

A covariant description of the canonical theory for interacting classical fields is developed on a space-like hypersurface. An identity invariant under the canonical transformations is obtained. The identity follows a canonical equation in which the interaction Hamiltonian density genarates a deformation of the space-like hypersurface. The equation just corr

A. V. Kotikov, G. Parente

We investigate the Q^2 evolution of parton distributions at small x values, obtained in the case of flat initial conditions. The results are in excellent agreement with deep inelastic scattering experimental data from HERA.

Arash Mafi

We present a solution to the $μ$ problem in an SO(10) supersymmetric grand unified (SUSY GUT) model with gauge mediated (GMSB) and D-term supersymmetry breaking. A Peccei-Quinn ({\bf PQ}) symmetry is broken at the messenger scale and enables the generation of the $μ$ term. The invisible axion (Goldstone boson of {\bf PQ} symmetry breaking) is a cold dark mat

D. Becirevic, V. Lubicz, G. Martinelli, F. Mescia

We present the first lattice calculation of the matrix element of the electromagnetic operator <pi0|Q+|K0>, where Q+ = (Q_d e/16 pi^2)* (\bar s_L sigma{mu,nu} F{mu,nu} d_R + \bar s_R sigma{mu,nu} F{mu,nu} d_L). This matrix element plays an important role, since it contributes to enhance the CP violating part of the K_L -> pi0 e+ e- amplitude in supersymmetri

J. Sato, K. Tobe, T. Yanagida

We present a new constraint on a lepton mixing matrix $V$ from lepton-flavor violating (LFV) processes in supersymmetric standard models with massive neutrinos. Here, we assume Yukawa-coupling unification $f_{ν3}\simeq f_{\rm top}$, in which $τ$-neutrino Yukawa coupling $f_{ν3}$ is unified into top-quark Yukawa coupling $f_{\rm top}$ at the unification scale

A. Rajantie, P. M. Saffin, E. J. Copeland

It has recently been suggested that the baryon washout problem of standard electroweak baryogenesis could be avoided if inflation ends at a low enough energy density and a parametric resonance transfers its energy repidly into the standard model fields. We present preliminary results of numerical simulations in a SU(2)xU(1) gauge-Higgs model in which this pr

De-Min Li, Hong Yu, Qi-Xing Shen

The Kawai model describing the glueball-quarkonia mixing is modified. The mixing of $η$, $η^\prime$ and $η(1410)$ is re-investigated based on the modified Kawai model. The glueball-quarkonia content of the three states is determined from a fit to the data of the electromagnetic decays involving $η$, $η^\prime$. Some predictions about the electromagnetic deca

Teruyuki Kitabayashi

We have constructed two $SU(3)_L \times U(1)_N$ gauge models with the $L^\prime = L_e-L_μ-L_τ$ symmetry, which accommodate tiny neutrino masses generated by one-loop and two-loop radiative effects. The heavy neutral leptons and heavy charged leptons are employed to specify the lepton triplets in $SU(3)_L$, respectively, accompanied by ($ϕ^0$, $ϕ^-$, $h^+$) a

A. Aurilia, E. Spallucci

The idea that a background of invisible material pervades the whole universe is as old as the history of natural philosophy. Modern particle physics and cosmology support that idea and identify in the cosmic vacuum the ultimate source of matter-energy, both seen and unseen, in the universe. In the framework of the inflation-axion scenario, we suggest an unus

Lingling Wu

The domain wall fermion formulation exhibits full chiral symmetry for finite lattice spacing except for the effects of mixing between the domain walls. Close to the continuum limit these symmetry breaking effects should be described by a single residual mass. We determine this mass from the conservation law obeyed by the conserved axial current in quenched s

J. C. Osborn

The meron-cluster algorithm was previously used to extensively study the physics associated with the spontaneous breaking of a discrete symmetry. We recently discovered that a larger class of models with spontaneous breaking of continuous symmetries can also be simulated using the meron-cluster algorithm. Here we study one of these new models which belongs t

Dean Lee

We review the method of stochastic error correction which eliminates the truncation error associated with any subspace diagonalization. Monte Carlo sampling is used to compute the contribution of the remaining basis vectors not included in the initial diagonalization. The method is part of a new approach to computational quantum physics which combines both d

Dean Lee

We discuss a method called quasi-sparse eigenvector diagonalization which finds the most important basis vectors of the low energy eigenstates of a quantum Hamiltonian. It can operate using any basis, either orthogonal or non-orthogonal, and any sparse Hamiltonian, either Hermitian, non-Hermitian, finite-dimensional, or infinite-dimensional. The method is pa

Chulwoo Jung, Robert G. Edwards, Xiangdong Ji, Valeriya Gadiyak

We study the effective quark mass induced by the finite separation of the domain walls in the domain-wall formulation of chiral fermion as the function of the size of the fifth dimension ($L_s$), the gauge coupling ($β$) and the physical volume ($V$). We measure the mass by calculating the small eigenvalues of the hermitian domain-wall Dirac operator ($H_{\r

T. Umeda, R. Katayama, H. Matsufuru, O. Miyamura

We study hadron properties near the deconfining transition in the finite temperature lattice QCD. This paper focus on the heavy quarkonium states, such as $J/ψ$ meson. We compare the meson correlators above and below $T_c$ and discuss the possibility of the $c\bar{c}$ bound state by observing the wave function.

F. Shoji

We formulate a stochastic gauge fixing method to study the gauge dependence of Abelian projection. In this method, one can change the gauge from the maximally Abelian one to no gauge fixing continuously. We have found that the linear part of the heavy quark potential from Abelian contribution depends little on the gauge parameter. Similar results have been o

Pushan Majumdar, Dong-Shin Shin

Recently Anishetty, Majumdar and Sharatchandra have proposed a way of characterizing topologically non-trivial configurations for 2+1-dimensional Yang-Mills theory in a local and manifestly gauge invariant manner. Here we develop criteria to locate such objects in lattice gauge theory and find them in numerical simulations.

JLQCD Collaboration, S. Aoki, R. Burkhalter, M. Fukugita

We report on our study of light hadron spectrum and quark masses in QCD with two flavors of dynamical quarks. Simulations are made with the plaquette gauge action and the non-perturbatively $O(a)$ improved Wilson quark action. We simulate 5 sea qaurk masses corresponding to $m_{PS}/m_{V} \simeq 0.8$--0.6 at $β=5.2$ on $12^3 \times 48$, $16^3 \times 48$ and $

Simon Hands, Istvan Montvay, Manfred Oevers, Luigi Scorzato

We study the global symmetries of SU(2) gauge theory with N flavors of staggered fermions in the presence of a chemical potential. We motivate the special interest of the case N=1 (staggered) with fermions in the adjoint representation of the gauge group. We present results from numerical simulations with both hybrid Monte Carlo and the Two-Step Multi-Bosoni

Ferdinando Gliozzi

In gauge systems coupled to matter, the static potential flattens out at a scale where the confining string breaks by formation of a dynamical pair of particles. Surprisingly, such a breaking is invisible in Wilson loops even when the inter-charge separation is much larger than the flattening scale. Observing string breaking also requires using different ope

S. Dalley, B. van de Sande

The boundstate problem in 2+1-dimensional large-N Yang-Mills theory is accurately solved using the light-front Hamiltonian of transverse lattice gauge theory. We conduct a thorough investigation of the space of couplings on coarse lattices, finding a single renormalised trajectory on which Poincaré symmetries are enhanced in boundstate solutions. Augmented b

PACS Collaboration, A. Ali Khan, S. Aoki, G. Boyd

We present the final results of the CP-PACS calculation of the light hadron spectrum and quark masses with two flavors of dynamical quarks. Simulations are made with a renormalization-group improved gauge action and a mean-field improved clover quark action for sea quark masses corresponding to $m_{\rm PS}/m_{\rm V} \approx 0.8$--0.6 and the lattice spacing