February 2002 arXiv papers — page 18

Dennis Lucarelli

A unifying framework for the control of quantum systems with non-Abelian holonomy is presented. It is shown that, from a control theoretic point of view, holonomic quantum computation can be treated as a control system evolving on a principal fiber bundle. An extension of methods developed for these classical systems may be applied to quantum holonomic syste

Kiyoshi Higashijima, Tetsuji Kimura, Muneto Nitta

We present a simple derivation of the Ricci-flat Kahler metric and its Kahler potential on the canonical line bundle over arbitrary Kahler coset space equipped with the Kahler-Einstein metric.

Cristian Lenart, Frank Sottile

We define skew Schubert polynomials to be normal form (polynomial) representatives of certain classes in the cohomology of a flag manifold. We show that this definition extends a recent construction of Schubert polynomials due to Bergeron and Sottile in terms of certain increasing labeled chains in Bruhat order of the symmetric group. These skew Schubert pol

Victor Ginzburg

We extend two well-known results on primitive ideals in enveloping algebras of semisimple Lie algebras, the `Irreducibility theorem' and `Duflo theorem', to much wider classes of algebras. Our general version of Irreducibility theorem says that if A is a positively filtered associative algebra such that gr(A) is a commutative Poisson algebra with fin

Vladimir Korepin, John Terilla

Shanon's fundamental coding theorems relate classical information theory to thermodynamics. More recent theoretical work has been successful in relating quantum information theory to thermodynamics. For example, Schumacher proved a quantum version of Shannon's 1948 classical noiseless coding theorem. In this note, we extend the connection between qua

Hideto Fukazawa, Yoshiteru Maeno

We report the filling control of the pyrochlore oxide Y2Ir2O7. Metallic ground state appears with increasing substitution content x (x >= 0.3). We have revealed that the density of states at the Fermi level rapidly changes with x by this filling control of Y2Ir2O7.

Dovi Poznanski, Avishay Gal-Yam, Dan Maoz, Alexei V. Filippenko

Large numbers of supernovae (SNe) have been discovered in recent years, and many more will be found in the near future. Once discovered, further study of a SN and its possible use as an astronomical tool (e.g., as a distance estimator) require knowledge of the SN type. Current classification methods rely almost solely on the analysis of SN spectra to determi

T. T. Nguyen, B. I. Shklovskii

We address the long standing problem of the dependence of the electrostatic persistence length $l_e$ of a flexible polyelectrolyte (PE) on the screening length $r_s$ of the solution within the linear Debye-Huckel theory. The standard Odijk, Skolnick and Fixman (OSF) theory suggests $l_e \propto r_s^2$, while some variational theories and computer simulations

Itamar Pitowsky

The worst violation of Bell's inequality for $n$ qbits is of size $2^{\frac{n-1}{2}}$ and it is obtained by a specific operator acting on a specific state. We show, to the contrary, that for a vast majority of Bell operators the worst violation is bounded by $O((n\log n)^{1/2})$, below experimental detection. With respect to the extremal operators, intro

S. Cht. Mavrodiev

It is demonstrate that the analysis of accuracy measurement of geomagnetic field and the behavior of local tide gravitational potential can serve as an earthquake precursor

E. Comay

It is proved that a source of electromagnetic radiation cannot emit a diffraction-free beam at the wave zone. A Bessel $J_0$ $ϕ$-invariant beam does not hold even at the intermediate zone. These results negate claims published recently in the literature.

D. Chistyakov

Explicit formulas are obtained for a family of continuous mappings of p-adic numbers $\Qp$ and solenoids $\Tp$ into the complex plane $\sC$ and the space \~$\Rs ^{3}$, respectively. Accordingly, this family includes the mappings for which the Cantor set and the Sierpinski triangle are images of the unit balls in $\Qn{2}$ and $\Qn{3}$. In each of the families

Z. Tevdoradze

Some functorial and topological properties of vertical cohomologies and their application to completely integrable Hamiltonian systems are studied.

Z. Tevdoradze

Some functorial properties are studied for the Hörmander classes defined for symplectic bundles. The behaviour of the Chern first form on a Lagrangian submanifold in an almost Hermitian manifold is also studied, and Fomenko's conjecture about the behaviour of a Maslov class on minimal Lagrangian submanifolds is considered.

Scott Baldridge

In this paper we show that the Seiberg--Witten invariant is zero for all smooth 4--manifolds with $b_+{>}1$ which admit circle actions that have at least one fixed point. Furthermore, we show that all symplectic 4--manifolds which admit circle actions with fixed points are rational or ruled, and thus admit a symplectic circle action.

Claudio Bonanno

We study the Manneville map f(x)=x+x^z (mod 1), with z>1, from a computational point of view, studying the behaviour of the Algorithmic Information Content. In particular, we consider a family of piecewise linear maps that gives examples of algorithmic behaviour ranging from the fully to the mildly chaotic, and show that the Manneville map is a member of thi

Paul H. Frampton

A long-standing problem of theoretical physics is the exceptionally small value of the cosmological constant $Λ\sim 10^{-120}$ measured in natural Planckian units. Here we derive this tiny number from a toroidal string cosmology based on closed strings. In this picture the dark energy arises from the correlation between momentum and winding modes that for sh

O. F. Dayi, L. T. Kelleyane

An electron moving on plane in a uniform magnetic field orthogonal to plane is known as the Landau problem. Wigner functions for the Landau problem when the plane is noncommutative are found employing solutions of the Schroedinger equation as well as solving the ordinary *-genvalue equation in terms of an effective Hamiltonian. Then, we let momenta and coord

Guey-Lin Lin

We introduce the technique of inverse Mellin transform in a problem of strong-field QED. We show that the {\it moments} of pair production width in a uniform background magnetic field are proportional to the derivatives of photon polarization function at the zero momentum. Hence, the pair-production width or the absorptive part of the photon polarization fun

Alan Kostelecky

In this talk, the status of CPT tests with neutral mesons is reviewed in the context of quantum field theory and the Lorentz- and CPT-violating standard-model extension.

Kenneth Lane

We test Arkani-Hamed et al.&#39;s dimensional deconstruction on a model that is predicted to have a naturally light composite Higgs boson, i.e., one whose mass M is much less than its binding scale Λ, and whose quartic coupling λis large, so that its vacuum expectation value v \sim M/\sqrtλ << Λalso. We consider two different underlying dynamics--UV completi

S. V. Shulga, S. -L. Drechsler

The strong coupling Schossmann-Schachinger theory for the upper critical field is considered methodically from the user point of view. We check the accuracy of approximate formulas for the upper critical field. In particular, we explain in detail as a recently proposed convenient expression (Shulga et al. cond-mat/0103154) can be justified. The connection of

A. K. Kolezhuk, H. -J. Mikeska

We study the dynamical structure factor of gapped one-dimensional spin systems in the critical phase in high magnetic field. It is shown that the presence of a ``condensate&#39;&#39; in the ground state in the high-field phase leads to interesting signatures in the response functions.

A. K. Kolezhuk

A large-S approach to the description of chiral phases in frustrated antiferromagnetic spin-S chains with easy-plane anisotropy is proposed. The approach is valid in the vicinity of the classical Lifshitz point j=1/4, where j is the relative strength of the frustrating next-nearest-neighbor coupling. The effective theory turns out to be the nonlinear sigma-m

R. Khomeriki, L. Tkeshelashvili

The possibility of nonlinear pulses generation in Yttrium Iron Garnet thin films for arbitrary direction between waveguide and applied static in-plane magnetic field is considered. Up to now only the cases of in-plane magnetic fields either perpendicular or parallel to waveguide direction have been studied both experimentally and theoretically. In the presen

Xiao-Gang Wen, A. Zee

Using 2D quantum spin-1/2 model as a concrete example, we studied the relation between gapless fermionic excitations (spinons) and quantum orders in some spin liquid states. Using winding number, we find the projective symmetry group that characterizes the quantum order directly determines the pattern of Fermi points in the Brillouin zone. Thus quantum order

Oliver Duerr, Wolfgang Dieterich, Philipp Maas, Abraham Nitzan

Recent experimental observations of anisotropic conductivity in stretched polymer electrolytes films of the polyethylene oxide family are discussed. The main experimental observations, enhancement of the ionic diffusion and conductivity in the stretch direction and decrease in these transport coefficients in the normal direction are interpreted in terms of a

Biman Nath, Suparna Roychowdhury

We study the possibility of quasar outflows in clusters and groups of galaxies heating the intracluster gas in order to explain the recent observation of excess entropy in this gas. We use the extended Press-Schechter formalism to estimate the number of quasars that become members of a group of cluster of a given mass and formation epoch. We also estimate th

C. Distefano, D. Guetta, E. Waxman, A. Levinson

It has been proposed recently that Galactic microquasars may be prodigious emitters of TeV neutrinos that can be detected by upcoming km^2 neutrino telescopes. In this paper we consider a sample of identified microquasars and microquasar candiates, for which available data enables rough determination of the jet parameters. By employing the parameters inferre

B. R. McNamara

Chandra images of galaxy clusters have revealed a wealth of structure unseen by previous generations of low resolution X-ray observatories. In the cores of clusters, bright, irregular X-ray emission is now routinely seen within central dominant galaxies (CDGs) harboring powerful radio sources. The radio sources are interacting with and are often displacing t

Makoto Hidaka, Yoshiaki Sofue

We derived a two-dimensional map of the molecular fraction, fmol, (the ratio of molecular-gas density to that of total gas) in the spiral galaxy M51, and examined the behavior of molecular fronts (MF), where MF represents the place where fmol changes drastically from nearly zero to unity and vice versa. We show that the MF phenomenon occurs not only radial,

Antonio Parravano, David J. Hollenbach, Christopher F. McKee

Far Ultraviolet radiation has been recognized as the main source of heating of the neutral interstellar gas, and, as a consequence, it determines whether the thermal balance of the neutral gas results in cold ($T\sim 50 - 100 K$) clouds (CNM), warm ($T \sim 10^4 K$) clouds (WNM), or a combination of the two. High FUV fields convert the neutral gas to WNM, wh

Margit Rösler, Marcel de Jeu

This paper studies the asymptotic behavior of the integral kernel of the Dunkl transform, the so-called Dunkl kernel, when one of its arguments is fixed and the other tends to infinity either within a Weyl chamber of the associated reflection group, or within a suitable complex domain. The obtained results are based on the asymptotic analysis of an associate

Cristiano Germani, Carlos F. Sopuerta

We consider braneworld scenarios including the leading correction to the Einstein-Hilbert action suggested by superstring theory, the Gauss-Bonnet term. We obtain and study the complete set of equations governing the cosmological dynamics. We find they have the same form as those in Randall-Sundrum scenarios but with time-varying four-dimensional gravitation

A. Gokalp, O. Yilmaz

We investigate the $ωσγ$-vertex and estimate the coupling constant g$_{ωσγ}$ in the framework of the light cone QCD sum rules. We compare our result with the values of this coupling constant deduced from a phenomenological analysis of $ω\toππγ$ decays.

Felix Finster

The &#34;principle of the fermionic projector&#34; provides a new mathematical framework for the formulation of physical theories and is a promising approach for physics beyond the standard model. The book begins with a brief review of relativity, relativistic quantum mechanics and classical gauge theories, with the emphasis on the basic physical concepts an

A. Jura, G. Kontrym-Sznajd, M. Samsel-Czekala

We present three-dimensional (3D) electron-positron momentum densities in Mg and Cd, reconstructed from 2D angular correlation of annihilation radiation data. By folding densities from the extended momentum space into the first Brillouin zone, we separated Fermi surfaces in various bands. Our results are in good agreement with band structure LMTO calculation

Anamaria Font, Alexis Hernandez

We study compact non-supersymmetric Z_N orbifolds in various dimensions. We compute the spectrum of several tachyonic type II and heterotic examples and partially classify tachyon-free heterotic models. We also discuss the relation to compactification on K3 and Calabi-Yau manifolds.

Lajos Diosi

We estimate an unknown qubit from the long sequence of n random polarization measurements of precision Delta. Using the standard Ito-stochastic equations of the aposteriori state in the continuous measurement limit we calculate the advancement of fidelity. We show that the standard optimum value 2/3 is achieved asymptotically for n >> Delta^2 / 96 >> 1. We a

Robert C. Hilborn

The relationships among various parameters describing the strength of optical transitions in atoms and molecules are reviewed. The application of these parameters to the description of the interaction between nearly monochromatic, directional light beams and atoms and molecules is given careful attention. Common pitfalls in relating these parameters are poin

David C. Montgomery, W. H. Matthaeus, L. J. Milano, P. Dmitruk

Numerical studies of the effect of a dc magnetic field on dynamo action (development of magnetic fields with large spatial scales), due to helically-driven magnetohydrodynamic turbulence, are reported. The apparent effect of the dc magnetic field is to suppress the dynamo action, above a relatively low threshold. However, the possibility that the suppression

V. Raicu

In spite of two hundred years of considerable efforts directed towards improvement in the experimental techniques, gravitational measurements have provided unsettled results for Newton&#39;s gravitational constant G. Analysis of the published (over ~75 years) small-scale gravitational measurements, presented in this report, unveils a large secular increase i

M. Beyer, S. Mattiello, T. Frederico, H. J. Weber

We present a relativistic in-medium three-body equation to study correlations in hot and dense quark matter. The equation is solved for a zero-range force for parameters close to the phase transition of QCD.

M. M. Sharma, A. R. Farhan

We have investigated the evolution of the shell structure of nuclei in going from the r-process path to the neutron drip line within the framework of the Relativistic Hartree-Bogoliubov (RHB) theory. By introducing the quartic self-coupling of $ω$ meson in the RHB theory in addition to the non-linear scalar coupling of $σ$ meson, we reproduce the available d

H. Shen

We construct the equation of state (EOS) in a wide density range for neutron stars using the relativistic mean field theory. The properties of neutron star matter with both uniform and non-uniform distributions are studied consistently. The inclusion of hyperons considerably softens the EOS at high densities. The Thomas-Fermi approximation is used to describ

Clint McCrory, Adam Parusinski

Algebraically constructible functions connect real algebra with the topology of algebraic sets. In this survey we present some history, definitions, properties, and algebraic characterizations of algebraically constructible functions, and a description of local obstructions for a topological space to be homeomorphic to a real algebraic set.

Aleksandr Golubchik

A polynomial algorithm for graphs&#39; isomorphism testing is constructed in assumption that there exists a corresponding polynomial algorithm for graphs with trivial automorphism group.

Taras Panov, Nigel Ray, Rainer Vogt

We study diagrams associated with a finite simplicial complex K, in various algebraic and topological categories. We relate their colimits to familiar structures in algebra, combinatorics, geometry and topology. These include: right-angled Artin and Coxeter groups (and their complex analogues, which we call circulation groups); Stanley-Reisner algebras and c

Joe Harris, Mike Roth, Jason Starr

We pose some questions about spaces parametrizing rational curves on rationally connected varieties. We give a partial answer for cubic threefolds. Many of our results were previously proved by Iliev, Markushevich and Tikhimirov by analyzing vector bundles on cubic threefolds. Our proofs use residuation rather than vector bundles.

Shinobu Hosono, Bong H. Lian, Keiji Oguiso, Shing-Tung Yau

We consider autoequivalences of the bounded derived category of coherent sheaves on a K3 surface. We prove that the image of the autoequivalences has index at most two in the group of the Hodge isometries of the Mukai lattice. Motivated by homological mirror symmetry we also consider the mirror counterpart, i.e. symplectic version of it. In the case of $ρ(X)

Roberto Iengo

We use a previously derived integral representation for the four graviton amplitude at two loops in Superstring theory, whose leading term for vanishing momenta gives the two-loop contribution to the R^4 term in the Effective Action. We find by an explicit computation that this contribution is zero, in agreement with a general argument implying the vanishing

Gerhard Buchalla

These lectures describe the most important theoretical methods in b-physics. We discuss the formalism of effective weak Hamiltonians, heavy quark effective theory, the heavy quark expansion for inclusive decays of b-hadrons and, finally, the more recent ideas of QCD factorization for exclusive nonleptonic B decays. While the main emphasis is put on introduci

Stephane Willocq

We report recent results in the study of rare hadronic and radiative penguin decays of B mesons. These results are based on a sample of 23 million B B-bar pairs collected by the BaBar Collaboration at the SLAC PEP-II e+e- B Factory.

S. G. Chung

The Landauer formula for electrical conductance is simple but works remarkably well in mesoscopic systems. We propose a Landauer-like formula for calculating an escape rate out of a dissipative metastable well, the quantum Kramers rate.

S. G. Chung

A non-band theory is developed to describe the superconductor-insulator (SI) transtition in resistively shunted, single Josephson junctions. The $I-V$ characteristic is formulated by a Landauer-like formula and evaluated by the path-integral transfer-matrix method. The result is consistent with the recent experiments at around 80 $mK$. However, the insulator

T. Temesvari, C. De Dominicis, I. R. Pimentel

Symmetry considerations and a direct, Hubbard-Stratonovich type, derivation are used to construct a replica field-theory relevant to the study of the spin glass transition of short range models in a magnetic field. A mean-field treatment reveals that two different types of transitions exist, whenever the replica number n is kept larger than zero. The Sherrin

Yusuke Tomita, Yutaka Okabe

We extend the newly proposed probability-changing cluster (PCC) Monte Carlo algorithm to the study of systems with the vector order parameter. Wolff&#39;s idea of the embedded cluster formalism is used for assigning clusters. The Kosterlitz-Thouless (KT) transitions for the two-dimensional (2D) XY and $q$-state clock models are studied by using the PCC algor

E. Comforti, Y. C. Chung, M. Heiblum, V. Umansky

Shot noise measurements were recently exploited to measure the charge of the quasiparticles in the Fractional Quantum Hall (FQH) regime. For fractional filling factors nu=1/3 and 2/5 of the first Landau level, fractional charges q=e/3 and e/5, respectively, were measured. We investigate here the interaction of e/3 quasiparticles with a strong backscatterer a

Yves Lansac, Prabal K. Maiti, Noel A. Clark, Matthew A. Glaser

Recently, a new class of smectic liquid crystal phases (SmCP phases) characterized by the spontaneous formation of macroscopic chiral domains from achiral bent-core molecules has been discovered. We have carried out Monte Carlo simulations of a minimal hard spherocylinder dimer model to investigate the role of excluded volume interations in determining the p

Christoph P. Hofmann

Nonrelativistic systems exhibiting collective magnetic behavior are analyzed within the framework of effective Lagrangians. The method, which formulates the dynamics of the system in terms of Goldstone bosons, allows to investigate the consequences of spontaneous symmetry breaking from a unified point of view. Analogies and differences with respect to the Lo

Xuedong Hu, S. Das Sarma

We theoretically consider possible errors in solid state quantum computation due to the interplay of the complex solid state environment and gate imperfections. In particular, we study two examples of gate operations in the opposite ends of the gate speed spectrum, an adiabatic gate operation in electron-spin-based quantum dot quantum computation and a sudde

L. Velazquez, F. Guzman

In the present paper it is analyzed a very simple example of pseudoextensive system, the tridimensional system of Linear Coupled Oscillators (OLA Model). The same one constitutes a classical tridimensional system of identical interacting particles by means of harmonic oscillators. This academic problem possesses a complete analytical solution allowing this w

V. Avila-Reese, C. Firmani

We find that the density distribution of high and low surface brightness (SB) galaxy disks formed within LCDM halos under the assumption of detailed angular momentum conservation is in rough agreement with observations. The luminous-to-dark matter ratio of the model galaxies increases with SB. The lowest SB models tend to be minimum disks, but the high SB mo

M. R. Burleigh, F. J. Clarke, S. T. Hodgkin

We suggest that Jovian planets will survive the late stages of stellar evolution, and that white dwarfs will retain planetary systems in wide orbits (>5AU). Utilising evolutionary models for Jovian planets, we show that infra-red imaging with 8m class telescopes of suitable nearby white dwarfs should allow us to resolve and detect companions >3Mjup. Detectio

A. V. Moiseev, V. L. Afanasiev, S. N. Dodonov

A current status of the observations with Interferometer Fabry-Perot (IFP) at the 6m telescope are described. A reduction of the data obtaining with a new focal reducer SCORPIO in IFP mode are outlined.

M. A. Beasley, C. M. Baugh, Duncan A. Forbes, R. M. Sharples

We have investigated the formation of globular cluster (GC) systems in the fiducial semi-analytic galaxy formation model of Cole et al. We assume that GCs are formed at high-redshift (z > 5) in proto-galactic fragments, and during the subsequent gas-rich merging of these fragments. We find that the mean ages of the metal-rich GCs are dependent upon host gala

Daniel A. Schwartz

We have searched for X-ray jets in the recent Chandra observations of three Sloan Digital Sky Survey (SDSS) quasars at redshift z ~ 6. All 3 quasars were detected in X-rays in these relatively short observations. SDSS 1030+0524 is not consistent with a point source, and may be a gravitationally lensed system. We find a possible jet-like feature 23&#34; from

Silas R. Beane, Martin J. Savage

We consider the nucleon-nucleon potential in quenched and partially-quenched QCD. The leading one-meson exchange contribution to the potential is found to fall off exponentially at long-distances, in contrast with the Yukawa-type behaviour found in QCD. This unphysical component of the two-nucleon potential has important implications for the extraction of nu

Tom Farris, John F. Gunion, Heather E. Logan

We survey techniques for finding a CP-odd Higgs boson, A, at the Linear Collider that do not depend upon the presence of other light Higgs bosons. The potential reach in $[m_A,\tanβ]$ parameter space for various production/discovery modes is evaluated and regions where discovery might not be possible at a given $\sqrt{s}$ are delineated. We give, for the fir

Piotr Sniady

We prove a family of new identities fulfilled by multinomial coefficients, which were conjectured by Dykema and Haagerup. Our method bases on a study of the, so-called, triangular operator T by the means of the free probability theory.

Igor R. Klebanov, Peter Ouyang, Edward Witten

We study effects associated with the chiral anomaly for a cascading $SU(N+M)\times SU(N)$ gauge theory using gauge/gravity duality. In the gravity dual the anomaly is a classical feature of the supergravity solution, and the breaking of the U(1) R-symmetry down to ${\bf Z}_{2M}$ proceeds via the Higgs mechanism.

D. Horan

A very high energy (VHE) gamma-ray signal has been detected at the 5.4 sigma level from H1426+428, an x-ray selected BL Lacertae object at a redshift of 0.129. The object was monitored from 1995 - 1998 with the Whipple 10m imaging atmospheric Cherenkov telescope as part of a general blazar survey; the results of these observations, although not statistically

Mark J Hadley

Contrary to established beliefs, spacetime may not be time-orientable. By considering an experimental test of time orientability it is shown that a failure of time-orientability of a spacetime region would be indistinguishable from a particle antiparticle annihilation event.

Stephane Lavignac, Isabella Masina, Carlos A. Savoy

In addition to the well established large atmospheric angle, a large solar angle is probably present in the leptonic sector. In the context of the see-saw and by means of a bottom-up approach, we explore which patterns for the Dirac and Majorana right-handed mass matrices provide two large mixings in a robust way and with the minimal amount of tuning. Three

B. E. Stern, J-L. Atteia, K. Hurley

We show that the source population of long gamma-ray bursts (GRBs) has declined by at least a factor of 12 (at the 90% confidence level) since the early stages of the Universe ($z \sim 2 - 3$). This result has been obtained using the combined BATSE and \it Ulysses \rm GRB brightness distribution and the detection of four GRBs with known redshifts brighter th

Steve Zelditch

We prove that a two-component mirror-symmetric analytic obstacle in the plane is determined by its resonance poles among such obstacles. The proof is essentially the same as in the interior case (part II of the series). A so-called interior/exterior duality formula is used to simplify the proof. A fair amount of exposition is included for the sake of complet

V. K. Magas, L. P. Csernai, D. Strottman

Different approaches to describe initial stages of relativistic heavy ion collisions are discussed qualitatively and quantitatively. An Effective String Rope Model is presented for heavy ion collisions at RHIC energies. Our model takes into account baryon recoil for both target and projectile, arising from the acceleration of partons in an effective field, p

Darryl D. Holm, Zhijun Qiao

We use the r-matrix formulation to show the integrability of geodesic flow on an $N$-dimensional space with coordinates $q_k$, with $k=1,...,N$, equipped with the co-metric $g^{ij}=e^{-|q_i-q_j|}\big(2-e^{-|q_i-q_j|}\big)$. This flow is generated by a symmetry of the integrable partial differential equation (pde) $m_t+um_x+3mu_x=0, m=u-α^2u_{xx}$ ($\al $ is

Jacek Dziarmaga, Krzysztof Sacha

Quantum depletion from an atomic quasi one dimensional Bose-Einstein condensate with a dark soliton is studied in a framework of the Bogoliubov theory. Depletion is dominated by an anomalous mode localized in a notch of the condensate wave function. Depletion in the anomalous mode requires different treatment than depletion without anomalous modes. In partic

Peter Grassberger

We present Monte Carlo estimates for site and bond percolation thresholds in simple hypercubic lattices with 4 to 13 dimensions. For d<6 they are preliminary, for d >= 6 they are between 20 to 10^4 times more precise than the best previous estimates. This was achieved by three ingredients: (i) simple and fast hashing which allowed us to simulate clusters of

E. V. Votyakov, H. I. Hidmi, A. De Martino, D. H. E. Gross

We derive the global phase diagram of a self-gravitating $N$-body system enclosed in a finite three-dimensional spherical volume $V$ as a function of total energy and angular momentum, employing a microcanonical mean-field approach. At low angular momenta (i.e. for slowly rotating systems) the known collapse from a gas cloud to a single dense cluster is reco

J. R. Gittings, A. J. Fisher

Quantum mechanical entanglement is a resource for quantum computation, quantum teleportation, and quantum cryptography. The ability to quantify this resource correctly has thus become of great interest to those working in the field of quantum information theory. In this paper, we show that all existing entanglement measures but one fail important tests of fi

B. Guberina, H. Stefancic

The problem of the $Ξ_{c}^{+}$ lifetime is considered in the framework of {\em Heavy-Quark Expansion} and $SU(3)_{flavor}$ symmetry. The lifetime of $Ξ_{c}^{+}$ is expressed in terms of measurable inclusive quantities of the other two charmed baryons belonging to the same $SU(3)_{flavor}$ multiplet in a model-independent way. In such a treatment, inclusive d

V. A. Rodin, A. E. L. Dieperink

A general continuum-RPA approach is developed to describe electromagnetic transitions between giant resonances. Using a diagrammatic representation for the three-point Green&#39;s function, an expression for the transition amplitude is derived which allows one to incorporate effects of mixing of single and double giant resonances as well as to take the entir

Satya N. Majumdar, Alan J. Bray

We introduce a general method, based on a mapping onto quantum mechanics, for investigating the large-T limit of the distribution P(r,T) of the nonlinear functional r[V] = (1/T)\int_0^T dT&#39; V[X(T&#39;)], where V(X) is an arbitrary function of the stationary Gaussian Markov process X(T). For T tending to infinity at fixed r we find that P(r,T) behaves as

Yves Brihaye, Betti Hartmann

We study spherically and axially symmetric monopoles of the SU(2) Einstein-Yang-Mills-Higgs-dilaton (EYMHD) system with a new coupling between the dilaton field and the covariant derivative of the Higgs field. This coupling arises in the study of (4+1)-dimensional vortices in the Einstein-Yang-Mills (EYM) system.

B. Geyer, D. M&#34;ulsch

A new type of topological matter interactions involving second-rank antisymmetric tensor matter fields with an underlying $N_T \geq 1$ topological supersymmetry are proposed. The construction of the 4-dimensional, $N_T = 1$ Donaldson-Witten theory, the $N_T = 1$ super-BF model and the $N_T = 2$ topological B-model with tensor matter are explicitly worked out

Leszek Hadasz, Zbigniew Jaskolski

The joining--splitting interaction of non-critical bosonic string is analyzed in the light-cone formulation. The Mandelstam method of constructing tree string amplitudes is extended to the bosonic massive string models of the discrete series. The general properties of the Liouville longitudinal excitations which are necessary and sufficient for the Lorentz c

Ji-sheng Chen, Jia-rong Li, Peng-fei Zhuang

The spectral function of rho meson in hot/dense hadronic matter is studied by taking into account the nucleon-loop on quantum hadrondynamics model level. Different from the hot pion gas effect which changes the spectral function slightly, the nucleon-antinucleon polarization (Dirac sea) makes the spectral function very sharp and shifted towards the low invar

C. Deroulers, A. P. Young

We study the dynamics of the q-state random bond Potts ferromagnet on the square lattice at its critical point by Monte Carlo simulations with single spin-flip dynamics. We concentrate on q=3 and q=24 and find, in both cases, conventional, rather than activated, dynamics. We also look at the distribution of relaxation times among different samples, finding d

J. Blümlein, D. Robaschik

Polarized inclusive deep-inelastic diffractive scattering is dealt with in a quantum field theoretic approach. The process can be described in the general framework of non-forward scattering processes using the light-cone expansion in the generalized Bjorken region applying the generalized optical theorem. The diffractive structure functions $g_1^{D(3)}$ and

Yuko Kobashi, Bhabani Prasad Mandal, Akio Sugamoto

The quantum Hall effect is studied by introducing two different matrix variables for electrons and holes, having Chern-Simons type interactions. By generalizing the constraint condition proposed by Susskind to realize the Pauli&#39;s exclusion principle in this two component matrix model, the classical exciton solution having excitation of both quasi-electro

Howard Baer, Csaba Balazs, Alexander Belyaev

We evaluate the relic density of neutralinos in the minimal supergravity (mSUGRA) model. All 2-->2 neutralino annihilation diagrams, as well as all processes involving sleptons, charginos, neutralinos and third generation squarks are included. Relativistic thermal averaging of the velocity times cross sections is performed. We find that co-annihilation effec

A. Boyarsky, B. Kulik

In this letter we address the problem of inducing boundary degrees of freedom from a bulk theory whose action contains higher-derivative corrections. As a model example we consider a topological theory with an action that has only a ``higher-derivative&#39;&#39; term. By choosing specific coupling of the brane to the bulk we show that the boundary action con

Homayoun Bagheri-Chaichian, Joachim Hermisson, Juozas R. Vaisnys, Gunter P. Wagner

Metabolic control analysis (Kacser & Burns (1973). Symp. Soc. Exp. Biol. 27, 65-104; Heinrich & Rapoport (1974). Eur. J. Biochem. 42, 89-95) was developed for the understanding of multi-enzyme networks. At the core of this approach is the flux summation theorem. This theorem implies that there is an invariant relationship between the control coefficients of

Christian Brouder

The Schwinger equations of QED are rewritten in three different ways as integral equations involving functional derivatives, which are called weak field, strong field, and SCF quantum electrodynamics. The perturbative solutions of these equations are given in terms of appropriate Feynman diagrams. The Green function that is used as an electron propagator in

B. G. Sidharth

We show that the Dirac theory of the electron, corresponds to recent approaches based on a Non commutative spacetime.

P. Banerjee, K. Krishan, S. Bhattacharya, C. Bhattacharya

We study theoretically fusion of the light proton-rich exotic nuclei $^{17}$F and $^8$B at near-barrier energies in order to investigate the possible role of breakup processes on their fusion cross sections. To this end, coupled channel calculations are performed considering the couplings to the breakup channels of these projectiles. In case of $^{17}$F, the

P. Banerjee, K. Krishan, S. Bhattacharya, C. Bhattacharya

The effect of inelastic excitation of exotic light projectiles (proton- as well as neutron-rich) $^{17}$F and $^{11}$Be on fusion with heavy target has been studied at near-barrier energies. The calculations have been performed in the coupled channels approach where, in addition to the normal coupling of the ground state of the projectile to the continuum, i

Michail P. Rekalo, Egle Tomasi-Gustafsson

In these notes we present a detailed and complete scheme for the calculation of polarization phenomena in elastic electron-nucleon scattering. The longitudinal and transversal components of the polarization for the scattered nucleon, induced by the scattering of longitudinally polarized electrons and the asymmetries for the collision of polarized electrons w