July 2000 arXiv papers — page 18

Chen-Ping Zhu, Shi-Jie Xiong

We investigate the localization behavior of electrons in a random lattice which is constructed from a quasi-one-dimensional chain with large coordinate number $Z$ and rewired bonds, resembling the small-world network proposed recently but with site-energy disorder and quantum links instead of classical ones. The random rewiring of bonds in the chain with lar

Fabio Bernardini, Maria Peressi, Vincenzo Fiorentini

We present ab-initio studies of band offsets, formation energy, and stability of (100) heterojunctions between (Zn,Be)(Se,Te) zincblende compounds, and in particular of the lattice-matched BeTe/ZnSe interface. Equal band offsets are found at Be/Se and Zn/Te abrupt interfaces, as well as at mixed interfaces, in agreement with the established understanding of

Makoto Yamashita, Masato Koashi, Tetsuya Mukai, Masaharu Mitsunaga

We study the evaporative cooling of magnetically trapped atomic hydrogen on the basis of the kinetic theory of a Bose gas. The dynamics of trapped atoms is described by the coupled differential equations, considering both the evaporation and dipolar spin relaxation processes. The numerical time-evolution calculations quantitatively agree with the recent expe

T. Mishonov

The aim of the present comment is to provoke the performance of simple additional measurements at Tc which, after a professional experimental data processing, will reveal an important quantitative information concerning the GL parameters and applicability of the GL theory for high-Tc superconductors in general. Confirmation of this would be crucial for the f

M. B. Walker

This article develops a quantitative quasiparticle model of the low-temperature properties of d-wave superconductors which incorporates both Fermi-liquid effects and band-structure effects. The Fermi-liquid interaction effects are found to be classifiable into strong and negligible renormalizaton effects, for symmetric and antisymmetric combinations of the e

Jeremy Taylor, Hong Guo, Jian Wang

We present an {\it ab initio} analysis of electron conduction through a $C_{60}$ molecular device. Charge transfer from the device electrodes to the molecular region is found to play a crucial role in aligning the lowest unoccupied molecular orbital (LUMO) of the $C_{60}$ to the Fermi level of the electrodes. This alignment induces a substantial device condu

A. Bovier, I. Kurkova, M. Loewe

We consider the random fluctuations of the free energy in the $p$-spin version of the Sherrington-Kirkpatrick model in the high temperature regime. Using the martingale approach of Comets and Neveu as used in the standard SK model combined with truncation techniques inspired by a recent paper by Talagrand on the $p$-spin version, we prove that (for $p$ even)

Jared C. Bronski, Lincoln D. Carr, Bernard Deconinck, J. Nathan Kutz

We present a new family of stationary solutions to the cubic nonlinear Schroedinger equation with a Jacobian elliptic function potential. In the limit of a sinusoidal potential our solutions model a dilute gas Bose-Einstein condensate trapped in a standing light wave. Provided the ratio of the height of the variations of the condensate to its DC offset is sm

J. Merino, Ross H. McKenzie

We show how the coupling between the phonons and electrons in a strongly correlated metal can result in phonon frequencies which have a non-monotonic temperature dependence. Dynamical mean-field theory is used to study the Hubbard-Holstein model that describes the κ-(BEDT-TTF)_2 X family of superconducting molecular crystals. The crossover with increasing te

Nadav M. Shnerb

Extinction transition of bacteria under forced rotation is analyzed in pie geometry. Under convection, separation of the radial and the azimuthal degrees of freedom is not possible, and the linearized evolution operator is diagonalized numerically. Some characteristics scales are compared with the results of recent experiments, and the ``integrable''

D. Schertzer, M. Larchevêque, J. Duan, V. V. Yanovsky

The Fokker-Planck equation has been very useful for studying dynamic behavior of stochastic differential equations driven by Gaussian noises. However, there are both theoretical and empirical reasons to consider similar equations driven by strongly non-Gaussian noises. In particular, they yield strongly non-Gaussian anomalous diffusion which seems to be rele

Priyamvada Natarajan, Omar Almaini

We use simple energetic arguments to estimate the contribution of massive X-ray binaries and supernova remnants to the cosmic X-ray background (XRB) at energies in excess of 2 keV. Recent surveys have shown that AGN probably account for most of the hard XRB (E > 2 keV), but there have been many suggestions that star-forming galaxies could emerge at fainter f

John W. MacKenty, Jesús Maíz-Apellániz, Christopher E. Pickens, Colin A. Norman

We present new H alpha and [O III] 5007 narrow band images of the starbursting dwarf galaxy NGC 4214, obtained with the WFPC2 onboard HST, together with VLA observations of the same galaxy. The HST images resolve features down to physical scales of 2-5 pc, revealing several young (<10 Myr) star forming complexes of various ionized gas morphologies (compact k

Alberto D. Bolatto, James M. Jackson, Frank P. Israel, Xiaolei Zhang

We present a study of carbon in N159/N160, an HII region complex in the low metallicity Large Magellanic Cloud. We have mapped this region, which comprises four distinct molecular clouds spanning a wide range of star-formation activity, in four transitions: 13CO (1-0) CO (2-1) and (4-3), and [CI] (1-0). Combining these data with existing [CII] observations p

Bradley M. Peterson, Amri Wandel

Emission-line variability data for Seyfert 1 galaxies provide strong evidence for the existence of supermassive black holes in the nuclei of these galaxies, and that the line-emitting gas is moving in the gravitational potential of that black hole. The time-delayed response of the emission lines to continuum variations is used to infer the size of the line-e

William T. Reach, Mark V. Sykes, David Lien, John K. Davies

We observed comet 2P/Encke with the Infrared Space Observatory ISOCAM on July 14, 1997 from a particularly favorable viewing geometry above the comet&#39;s orbital plane and at a distance of 0.25 AU. A structured coma was observed, along with a long, straight dust trail. For the first time, we are able to observe the path of particles as they evolve from the

Kengo Tachihara, Rihei Abe, Toshikazu Onishi, Akira Mizuno

Molecular clouds around a run-away O star z Oph have been surveyed with NANTEN telescope and their streaming motion caused by z Oph has been detected. z Oph is the earliest member of the Sco OB2 association and is a runaway star rapidly moving with an HII region, S27. We detected 2 major filamentary cloud complexes; one including L156 (L156 complex) is lying

Christian Theis

Though it is generally assumed that massive molecular clouds are the progenitors of globular clusters, their detailed formation mechanism is still unclear. Standard scenarios based on the collapse of a smooth matter distribution suffer from strong requirements with respect to cluster formation time scale, binding energy and star formation efficiency. An alte

K. D. Gordon, A. N. Witt, R. J. Rudy, R. C. Puetter

We present 0.35 to 2.5 micron spectra of the south and northwest filaments in the reflection nebula NGC 7023. These spectra were used to test the theory of Seahra & Duley that carbon nanoparticles are responsible for Extended Red Emission (ERE). Our spectra fail to show their predicted second emission band at 1.0 micron even though both filaments exhibit str

Shane L. Larson, Rudolph Schild

Studies of the lensed quasar ${\rm Q}0957+561 {\rm A,B}$ have shown evidence for microlensing in the brightness history of the quasar images. It had been suggested that a frequency offset between the brightness fluctuations in each of the two images might possibly be caused by gravitational radiation generated by a massive black hole binary at the center of

Giuseppe Bertin, Marco Lombardi

The analysis of the shear induced by a single cluster on the images of a large number of background galaxies is all centered around the curl-free character of a well-known vector field that can be derived from the data. Such basic property breaks down when the source galaxies happen to be observed through two clusters at different redshifts, partially aligne

Boudewijn F. Roukema

It has been suggested that if the Universe satisfies a flat, multiply connected, perturbed Friedmann-Lema^itre model, then cosmic microwave background data from the COBE satellite implies that the minimum size of the injectivity diameter (shortest closed spatial geodesic) must be larger than about two fifths of the horizon diameter. To show that this claim i

Falk Herwig

The influence of extended convective mixing (overshoot) on asymptotic giant branch stellar evolution is investigated in detail. The extended mixing is treated time-dependently, and the efficiency declines exponentially with the geometric distance from the convective boundary. It has been considered at all convective boundaries, including the He-flash convect

Eamonn Kerins

I review proposals for explaining the current gravitational microlensing results from the EROS and MACHO surveys towards the Magellanic Clouds. Solutions involving massive compact halo objects (MACHOs), both baryonic and non-baryonic, as well as solutions that do not require MACHOs, are discussed. Whilst the existence and nature of MACHOs remains to be estab

I. Burud, J. Hjorth, A. O. Jaunsen, M. I. Andersen

We present optical I-band light curves of the gravitationally lensed double QSO B1600+434 from observations obtained at the Nordic Optical Telescope (NOT) between April 1998 and November 1999. The photometry has been performed by simultaneous deconvolution of all the data frames, involving a numerical lens galaxy model. Four methods have been applied to dete

Eline Tolstoy, Michael Irwin

We present the results of a VLT observing program carried out in service mode using FORS1 on ANTU in Long Slit mode to determine the optical velocities of nearby low surface brightness galaxies. Outlying Local Group galaxies are of paramount importance in placing constraints the dynamics and thus on both the age and the total mass of the Local Group. Optical

Donald Lynden-Bell

Application of Newton&#39;s ideas from &#34;Principia&#34; gives many new results in mechanics. Here we explore the question ``What form of extra force will maintain the magnitude of a vector constant of the motion while changing its direction?&#39;&#39;

Oliver Czoske, Jean-Paul Kneib, Ian Smail, Graham P. Smith

We describe a project to study a sample of X-ray luminous clusters of galaxies at redshift z~0.2 at several scales (with HST/WFPC2 and CFHT/CFH12k) and wavebands (optical and X-ray). The main aims of the project are (i) to determine the mass profiles of the clusters on scales ranging from ~10 kpc/h to >1.5 Mpc/h using weak and strong lensing, thereby testing

K. G. Noeske, N. G. Guseva, K. J. Fricke, Y. I. Izotov

&#34;Cometary&#34; Blue Compact Dwarf Galaxies (iI,C BCDs) are characterized by off-center starbursts close to the end of an elongated dwarf irregular (dI)-like host galaxy. This may either represent randomly enhanced star-forming activity of a dI, or may be caused by a set of special properties of such systems or their environment. For a first investigation

R. de Ritis, A. A. Marino

In this paper we present exactly solved extended quintessence models; furthermore, through a dynamical effective Q-cosmological &#34;constant&#34;, we recover some of the L decaying cases found in the literature. Finally we introduce a sort of complementarity between the Q-dominated or L-dominated expansions of the Universe.

G. Gavazzi, C. Bonfanti, P. Pedotti, A. Boselli

Optical spectroscopy of 76 galaxies, 48 of which are projected in the direction of the Virgo cluster and 28 onto the Coma-A1367 supercluster, is reported. Adding these new measurements to those found in the literature, the redshift completeness in the Virgo region becomes 92% at B_T<=16.0 and 68% at B_T<=18.0. The one of CGCG galaxies in the direction of the

K. Rines, M. J. Geller, A. Diaferio, J. J. Mohr

We describe observations of the nearby cluster of galaxies A576 beyond the virial radius and into the infall region. Using 1057 redshifts, we use the infall pattern in redshift space to determine the mass profile of A576 to a radius of ~4 Mpc/h. This mass estimation technique makes no assumptions about the equilibrium state of the cluster. Within 1 Mpc/h, th

R. Srikanth

In response to the comments of astro-ph/0006426 on Srikanth (Icarus 1999), we clarify, and thereby justify, the definition of Poynting-Robertson drag adopted in the latter. We confirm that dust absorption is a necessary condition while re-emission is neither necessary nor sufficient for the inspiralling of a rest-isotropically emitting dust.

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

Results of 2D spectral observations for 4 Sy galaxies with ionization cones are presented. Images in the [OIII] line, velocity fields of the ionized gas, stellar velocity and velocity dispersion fields were obtained at the SAO RAS 6m telescope. Non-circular gas motions and Z-shaped emission filaments could be explained as helical waves located in the ionizat

A. Freitas, W. Hollik, W. Walter, G. Weiglein

The complete fermionic two-loop contributions to the prediction for the W-boson mass from muon decay in the electroweak Standard Model are evaluated exactly, i.e. no expansion in the top-quark and the Higgs-boson mass is made. The result for the W-boson mass is compared with the previous result of an expansion up to next-to-leading order in the top-quark mas

Laurent Bartholdi

We introduce L-presentations: group presentations given by a generating set, a set of relations and a set of substitution rules on the generating set producing more relations. We first study in full generality the structure of finitely L-presented groups, i.e. groups for which all the above sets are finite, and then show that a broad class of groups acting o

S. A. McGee, M. J. Holland

We derive the frequency of precession and conditions for stability for a quantized vortex in a single-component and a two-component Bose-Einstein condensate. The frequency of precession is proportional to the gradient of the free energy with respect to displacement of the vortex core. In a two-component system, it is possible to achieve a local minimum in th

Christoph Hanhart, Daniel R. Phillips, Sanjay Reddy, Martin J. Savage

One of the strongest constraints on the existence of large, compact, &#34;gravity-only&#34; dimensions comes from SN1987a. If the rate of energy loss into these putative extra dimensions is too high, then the neutrino pulse from the supernova will differ from that actually seen. The dominant mechanism for the production of Kaluza-Klein gravitons and dilatons

Hy Trac, Dimitris Mitsouras, Paul Hickson, Robert H. Brandenberger

The topology of the Las Campanas Redshift Survey is analyzed using Minkowski functional statistics, taking into account the selection effects of the survey. The results are compared with the predictions of some toy models of structure formation, including the Standard Cold Dark Matter Model and topological defect-based models. All of the toy models have a sc

V. M. Apalkov, T. Chakraborty, P. Pietilainen, K. Niemela

We report a theoretical analysis of the half-polarized quantum Hall states observed in a recent experiment. Our numerical results indicate that the ground state energy of the quantum Hall $ν= 2/3$ and $ν= 2/5$ states versus spin polarization has a downward cusp at half the maximal spin polarization. We map the two-component fermion system onto a system of ex

J. Gamboa, S. Lepe an L. Vergara

derivation of the effective lagrangian for non-relativistic quantum chromodynamics and the heavy quarks effective field theory is given. Our calculation provides of a simple and systematic method of calculation of the full off shell effective lagrangian at tree level including all the $1/m$ corrections.

Larry Zamick, Shadow J. Q. Robinson

We adopt a personal approach here reviewing several calculations over the years in which we have experienced confrontations between cluster models and the shell model. In previous cluster conferences we have noted that cluster models go hand in hand with Skyrme Hartee-Fock calculations in describing states which cannot easily, if at all, be handled by the sh

Karl Gebhardt, John Kormendy, Luis Ho, Ralf Bender

Black hole (BH) masses that have been measured by reverberation mapping in active galaxies fall significantly below the correlation between bulge luminosity and BH mass determined from spatially resolved kinematics of nearby normal galaxies. This discrepancy has created concern that one or both techniques suffer from systematic errors. We show that BH masses

F. Gelis

Thermal amplitudes with ultrasoft momenta, which are not accessible by standard methods of perturbation theory, have recently attracted a lot of interest. However, the comparison of external momenta with the ultrasoft scale $g^2T\ln(1/g)$ is a too crude criterion, since amplitudes with hard external momenta can also be non perturbative, if these momenta are

Charles A. Nelson, L. J. Adler,

To enable an evaluation of future measurements of the helicity parameters for &#34; t --> W b &#34; decay in regard to &#34; T_FS violation&#34;, this paper considers the effects of an additional pure-imaginary coupling, (i g/2 Lambda) or (i g), associated with a specific, single additional Lorentz structure, i = S, P, S + P, ... Sizable &#34; T_FS violation

M. A. N. Araujo, N. M. R. Peres, P. D. Sacramento, V. R. Vieira

We present a mean-field study of superconductivity in a generalized N-channel cubic Anderson lattice at U=\infty taking into account the effect of a nearest-neighbor attraction J. The condition U=\infty is implemented within the slave-boson formalism considering the slave bosons to be condensed. We consider the $f$-level occupancy ranging from the mixed vale

Jean-Paul Blaizot, Phuong Mai Dinh, Jean-Yves Ollitrault

The NA50 collaboration has recently observed that the J/psi production rate in Pb-Pb collisions decreases more rapidly as a function of the transverse energy for the most central collisions than for less central ones. We show that this phenomenon can be understood as an effect of transverse energy fluctuations in central collisions. A good fit of the data is

Olaf Lechtenfeld, Alexander Sorin

An N=(2|2) superfield formulation of the N=(1|1) supersymmetric Toda lattice hierarchy is proposed, and its five real forms are presented.

Dileep P. Jatkar, Gautam Mandal, Spenta R. Wadia

We construct Nielsen-Olesen vortex solution in the noncommutative abelian Higgs model. We derive the quantized topological flux of the vortex solution. We find that the flux is integral by explicit computation in the large $θ$ limit as well as in the small $θ$ limit. In the context of a tachyon vortex on the brane-antibrane system we demonstrate that it is t

Frederico F. de Souza Cruz, Marcus B. Pinto, Rudnei O. Ramos

We apply the non-perturbative optimized linear $δ$ expansion method to the O(N) scalar field model in three-dimensions to determine the transition temperature of a dilute homogeneous Bose gas. Our results show that the shift of the transition temperature, $ΔT_c/T_c$, of the interacting model, compared with the ideal gas transition temperature, really behaves

A. S. Mel&#39;nikov

On the basis of the Bogolubov-de Gennes theory we develop an analytical description of low-energy extended quasiparticle states around an isolated flux line in a superconductor with gap nodes. The wavefunctions of these excitations and the corresponding density of states are shown to be strongly influenced by the interaction with a pure gauge potential due t

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

We show that the data for diffractive dijet production at the Tevatron p pbar collider are consistent with diffractive deep inelastic e p data collected at HERA. The breakdown of factorization between the two data sets is naturally explained by a strong tendency to populate the rapidity gap in the p pbar diffractive process by secondaries from soft underlyin

S. Descotes, J. Stern

We discuss the influence of the vacuum fluctuations of \bar{q}q pairs on low-energy constants and condensates. The analysis of the Goldstone boson masses and decay constants shows that the three-flavour condensate and some low-energy constants are very sensitive to the value of L_6, which measures the Zweig-rule violation in the scalar channel. A chiral sum

Marco Mackaay, Roger Picken

In this paper we establish a one-to-one correspondence between $S^1$-gerbes with connections, on the one hand, and their holonomies, for simply connected manifolds, or their parallel transports, in the general case, on the other hand. This result is a higher-order analogue of the familiar equivalence between bundles with connections and their holonomies for

Banibrata Mukhopadhyay, Sandip K. Chakrabarti

Chandrasekhar separated the Dirac equation for spinning and massive particles in Kerr geometry in radial and angular parts. Chakrabarti solved the angular equation and found the corresponding eigenvalues for different Kerr parameters. The radial equations were solved asymptotically by Chandrasekhar. In the present paper, we use the WKB approximation to solve

Suresh Govindarajan, T. Jayaraman, Tapobrata Sarkar

We study both A-type and B-type D-branes in the gauged linear sigma model by considering worldsheets with boundary. The boundary conditions on the matter and vector multiplet fields are first considered in the large-volume phase/non-linear sigma model limit of the corresponding Calabi-Yau manifold, where we also find that we need to add a contact term on the

Erricos C. Pavlis, Lorenzo Iorio

The general relativistic Lense-Thirring effect can be detected by means of a suitable combination of orbital residuals of the laser-ranged LAGEOS and LAGEOS II satellites. While this observable is not affected by the orbital perturbation induced by the zonal Earth solid and ocean tides, it is sensitive to those generated by the tesseral and sectorial tides.

Lorenzo Iorio

In order to detect the gravitomagnetic clock effect by means of two counter-orbiting satellites placed on identical equatorial and circular orbits around the Earth with radius 7000 km their radial and azimuthal positions must be known with an accuracy of delta r =10^{-1} mm and delta phi =10^{-2} mas per revolution. In this work we investigate if the radial

Walter D. Goldberger, Ira Z. Rothstein

We investigate the role of quantum fluctuations in the system composed of two branes bounding a region of AdS. It is shown that the modulus effective potential generated by quantum fluctuations of both brane and bulk fields is incapable of stabilizing the space naturally at the separation needed to generate the hierarchy. Consequently, a classical stabilizat

K. -I. Izawa

We consider a quintessential sector realized on a hidden brane with a tiny warp factor, which implies a small value of the effective four-dimensional cosmological constant through an equation of motion for the quintessential scalar.

I. V. Sokolov, M. I. Kolobov, A. Gatti, L. A. Lugiato

We describe a continious variable teleportation scheme that allows to teleport the quantum state of distributed in space-time multimode electromagnetic field. Our teleportation protocol uses the spatially-multimode entangled Einstein-Podolsky-Rosen lihgt beams. We evaluate the &#34;resolving power&#34; of teleportation in space-time and specify the degrees o

John Jeffers

By directing the input light into a particular mode it is possible to obtain as output all of the input light for a beam splitter that is 50% absorbing. This effect is also responsible for nonlinear quantum interference when two photons are incident on the beam splitter.

E. L. Afraimovich

This author suggests the concept of a new technology for global detection (GLOBDET) of atmospheric disturbances of natural and technogenic origin, on the basis of phase measurements of the total electron content (TEC) in the ionosphere using an international GPS network. Temporal dependencies of TEC are obtained for a set of spaced receivers of the GPS netwo

E. L. Afraimovich, E. A. Kosogorov, O. S. Lesyuta

We present the results derived from measuring fundamental parameters of the ionospheric response to the August 11, 1999 total solar eclipse. Our study is based on using the data from about 70 GPS stations located in the neighbourhood of the eclipse totality phase in Europe. The eclipse period was characterized by a low level of geomagnetic disturbance (Dst -

S. Kümmel, M. Brack, P. -G. Reinhard

We determined the ionic and electronic structure of sodium clusters with even electron numbers and 2 to 59 atoms in axially averaged and three-dimensional density functional calculations. A local, phenomenological pseudopotential that reproduces important bulk and atomic properties and facilitates structure calculations has been developed. Photoabsorption sp

Thomas Schaefer

We point out that the problem of kaon condensation in dense hadronic matter can be addressed in perturbative QCD. Indeed, perturbative calculations suggest that negative kaons are condensed in high density quark matter if the electroweak interaction is taken into account. This observation sheds new light on the proposal that the low density hyperon and high

E. L. Bratkovskaya, W. Cassing, C. Greiner, M. Effenberger

We study thermal and chemical equilibration in &#39;infinite&#39; hadron matter as well as in finite size relativistic nucleus-nucleus collisions using a BUU cascade transport model with resonance and string degrees-of-freedom. The &#39;infinite&#39; hadron matter is simulated within a cubic box employing periodic boundary conditions. The various equilibrati

I. A. Pshenichnov, J. P. Bondorf, S. Masetti, I. N. Mishustin

We study the simultaneous dissociation of heavy ultrarelativistic nuclei followed by the forward-backward neutron emission in peripheral collisions at colliders. The main contribution to this particular heavy-ion dissociation process, which can be used as a beam luminosity monitor, is expected to be due to the electromagnetic interaction. The Weizsacker-Will

H. K. T. van der Molen, H. Akimune, A. M. van den Berg, I. Daito

Decay via proton emission of isobaric analog states (IAS&#39;s) in $^{91}{Nb}$ was studied using the $^{90}{Zr}(α,t)$ reaction at $E_α$=180 MeV. This study provides information about the damping mechanism of these states. Decay to the ground state and low-lying phonon states in $^{90}{Zr}$ was observed. The experimental data are compared with theoretical pre

A. Schiller, M. Guttormsen, M. Hjorth-Jensen, E. Melby

A convergent method to extract the nuclear level density and the gamma-ray strength function from primary gamma-ray spectra has been established. Thermodynamical quantities have been obtained within the microcanonical and canonical ensemble theory. Structures in the caloric curve and in the heat capacity curve are interpreted as fingerprints of breaking of C

J. Materna, J. Liptak, F. Sterba, J. Sterbova

Radiative decay of 21 resonances in the 55Mn(p,g)56Fe reaction was studied in the proton beam energy region Ep = 1.3 - 1.8 MeV. Branching of decay to many low lying bound states up to excitation energy Ex ~ 8 MeV was measured. Exact energy of all resonances has been established what pointed out that five of the resonances are very close doublets. For all stu

A. Martinez, S. Wiggins

We consider a Hamiltonian $H=H^{0}(p)+κH^{1}(p,q,t)$, $(p,q)\in {\mathbb{R}}^{n} \times {\mathbb{T}}^n$, $t\in{\mathbb{R}}$ where $κ\in {\mathbb{R}}$ is a small perturbation parameter and $p$, $q$ are the action and angle variables respectively. The Hamiltonian generates an autonomous vector field obtained by extending the phase space making $t$ a dependent

T. Gilbert, J. R. Dorfman, P. Gaspard

We consider the time-dependent statistical distributions of diffusive processes in relaxation to a stationary state for simple, two dimensional chaotic models based upon random walks on a line. We show that the cumulative functions of the hydrodynamic modes of diffusion form fractal curves in the complex plane, with a Hausdorff dimension larger than one. In

Marek Biskup, Wolfgang Koenig

We consider the large-time behavior of the solution $u\colon [0,\infty)\times\Z\to[0,\infty)$ to the parabolic Anderson problem $\partial_t u=κΔu+ξu$ with initial data $u(0,\cdot)=1$ and non-positive finite i.i.d. potentials $(ξ(z))_{z\in\Z}$. Unlike in dimensions $d\ge2$, the almost-sure decay rate of $u(t,0)$ as $t\to\infty$ is not determined solely by the

M. Grott, K. -H. Rehren

Local quantum fields in 1+1 dimensions can have bounded field operators. The class of such fields which in addition obey Huygens&#39; principle (time-like commutativity) and conformal covariance, is completely determined.

K. -H. Rehren, H. R. Tuneke

The Virasoro algebra with c=1 has a continuum of superselection sectors characterized by the ground state energy h. Only a discrete subset of sectors arises by restriction of representations of the SU(2) current algebra at level k=1. The remaining continuum of sectors is obtained with the help of (localized) homomorphisms into the current algebra. The fusion

Stephen Montgomery-Smith

We consider an equation similar to the Navier-Stokes equation. We show that there is initial data that exists in every Triebel-Lizorkin or Besov space (and hence in every Lebesgue and Sobolev space), such that after a finite time, the solution is in no Triebel-Lizorkin or Besov space (and hence in no Lebesgue or Sobolev space). The purpose is to show the lim

Mark Goresky, William Pardon

Let X be a Hermitian locally symmetric space. We prove that every Chern class of X has a canonical lift to the cohomology of the Baily- Borel-Satake compactification X* of X and that the resulting Chern numbers satisfy the Hirzebruch proportionality formula with respect to the compact dual X^ of X. The same result holds for any automorphic vector bundle over

Constantin Udriste

Using parametrized curves (Section 1) or parametrized sheets (Section 3), and suitable metrics, we treat the jet bundle of order one as a semi-Riemann manifold. This point of view allows the description of solutions of DEs as pregeodesics (Section 1) and the solutions of PDEs as potential maps (Section 3), via Lagrangians of order one or via generalized Lore

Constantin Udriste

Section 1 refines the theory of harmonic and potential maps. Section 2 defines a generalized Lorentz world-force law and shows that any PDEs system of order one generates such a law in suitable geometrical structure. In other words, the solutions of any PDEs system of order one are harmonic or potential maps, if we use semi-Riemann-Lagrange structures. Secti

C. Udriste, A. Udriste

Recall that a vector field on an n-dimensional differentiable manifold M is a mapping X defined on M with values in the tangent bundle TM that assigns to each point $x\in M$ a vector X(x) in the tangent space $T_x M$. A vector field may be interpreted alternatively as the right-hand side of an autonomous system of first-order ordinary differential equations,

S. J. Montgomery-Smith, E. M. Semenov

We give partial answers to the following conjecture: the natural embedding of a rearrangement invariant space E into L_1([0,1]) is strictly singular if and only if G does not embed into E continuously, where G is the closure of the simple functions in the Orlicz space L_Phi with Phi(x) = exp(x^2)-1.

Xiuxiong Chen

Donaldson conjectured \cite{Dona96} that the space of Kähler metrics is geodesic convex by smooth geodesic and that it is a metric space. Following Donaldson&#39;s program, we verify the second part of Donaldson&#39;s conjecture completely and verify his first part partially. We also prove that the constant scalar curvature metric is unique in {\bf each} Käh

Stefano Bianchini, Rinaldo M. Colombo

We consider the dependence of the entropic solution of a hyperbolic system of conservation laws \[ \{\{array}{c} u_t + f(u)_x = 0 u(0,\cdot) = u_0 \{array} \] on the flux function f. We prove that the solution in Lipschitz continuous w.r.t.~the $C^0$ norm of the derivative of the perturbation of f. We apply this result to prove the convergence of the solutio

Yasushi Homma

We present a generalization of the Clifford action for other representations spaces of $Spin(n)$, which is called the Clifford homomorphism. Their properties extend to the ones for the higher spin Dirac operators on spin manifolds. In particular, we have general Bochner identities for them, and an eigenvalue estimate of a Laplace type operator on any associa

Peter Kuchment, Yehuda Pinchover

The paper contains integral representations for certain classes of exponentially growing solutions of second order periodic elliptic equations. These representations are the analogs of those previously obtained by S. Agmon, S. Helgason, and other authors for solutions of the Helmholtz equation. When one restricts the class of solutions further, requiring the

J. Böckenhauer, D. E. Evans

In these lectures we explain the intimate relationship between modular invariants in conformal field theory and braided subfactors in operator algebras. A subfactor with a braiding determines a matrix $Z$ which is obtained as a coupling matrix comparing two kinds of braided sector induction (&#34;alpha-induction&#34;). It has non-negative integer entries, is

Robin Endelman, Timothy J. Hodges

An explicit quantization is given of certain skew-symmetric solutions of the classical Yang-Baxter, yielding a family of $R$-matrices which generalize to higher dimensions the Jordanian $R$-matrices. Three different approaches to their construction are given: as twists of degenerations of the Shibukawa-Ueno Yang-Baxter operators on meromorphic functions; as

Andriy Panasyuk

A method of constructing a class of bihamiltonian structures is presented. Elements of this class are generalizations of the so-called bihamiltonian structures of general position on odd-dimensional manifolds. The method consists in a simultaneous reduction of both the real and imaginary parts of a complex symplectic form. Necessary and sufficient conditions

F. Lenz, M. Thies, K. Yazaki

In light-cone quantization, the standard procedure to characterize the phases of a system by appropriate ground state expectation values fails. The light-cone vacuum is determined kinematically. We show that meaningful quantities which can serve as order parameters are obtained as expectation values of Heisenberg operators in the equal (light-cone) time limi

M. Gomes, J. M. C. Malbouisson, A. G. Rodrigues, A. J. da Silva

We discuss the scattering of relativistic spin zero particles by an infinitely long and arbitrarily thin solenoid. The exact solution of the first-quantized problem can be obtained as a mimic of the nonrelativistic case, either in the original Aharonov-Bohm way or by using the Berry&#39;s magnetization scheme. The perturbative treatment is developed in the F

P. Dimopoulos, K. Farakos, A. Kehagias, G. Koutsoumbas

We examine the problem of gauge-field localization in higher-dimensional gauge theories. In particular, we study a five-dimensional U(1) by lattice techniques and we find that gauge fields can indeed be localized. Two models are considered. The first one has anisotropic couplings independent of each other and of the coordinates. It can be realized on a homog

P. Dorey, M. Pillin, R. Tateo, G. M. T. Watts

We consider the one-point functions of bulk and boundary fields in the scaling Lee-Yang model for various combinations of bulk and boundary perturbations. The one-point functions of the bulk fields are analysed using the truncated conformal space approach and the form-factor expansion. Good agreement is found between the results of the two methods, though we

K. Lechner, P. A. Marchetti

This paper presents a general covariant lagrangian framework for the dynamics of a system of closed n-branes and dual (D-n-4)-branes in D dimensions, interacting with a dynamical (n+1)-form gauge potential. The framework proves sufficiently general to include also a coupling of the branes to (the bosonic sector of) a dynamical supergravity theory. We provide

Aristophanes Dimakis, Folkert Muller-Hoissen

We construct a deformation quantized version (ncKdV) of the KdV equation which possesses an infinite set of conserved densities. Solutions of the ncKdV are obtained from solutions of the KdV equation via a kind of Seiberg-Witten map. The ncKdV is related to a modified ncKdV equation by a noncommutative Miura transformation.

Fardin Kheirandish, Mohammad Khorrami

A general two-dimensional fractional supersymmetric conformal field theory is investigated. The structure of the symmetries of the theory is studied. Applying the generators of the closed subalgebra generated by $(L_{-1},L_{0},G_{-1/(F+1)})$ and $(\bar{L}_{-1},\bar{L}_{0},\bar{G}_{-1/(F+1)})$, the two point functions of the component-fields of supermultiplet

J. Bellorin, A. Restuccia

A class of exact solutions to the Born-Infeld field equations, over manifolds of any even dimension, is constructed. They are an extension of the self-dual configurations. They are local minima of the action for riemannian base manifolds and local minima of the Hamiltonian for pseudo-riemannian ones. A general explicit expression for the Born-Infeld determin

Harold W. Fearing, Thomas R. Hemmert, Randy Lewis, Christine Unkmeir

The differential cross sections and s-wave and p-wave multipoles for $π^- p \to γn$ and $π^+ n \to γp$ have been calculated through $O(p^3)$ in heavy baryon chiral perturbation theory (HBChPT). Fits to existing data allow several of the low energy constants to be determined. Generally results of the calculation compare well with dispersion relation predictio

K. G. Chetyrkin, A. Retey

In this paper we present a full set of 2- and 3-point functions for massless QCD at three-loop order in the MSbar scheme. The vertex functions are evaluated at the asymmetric point with one vanishing momentum. These results are used to relate the MSbar coupling constant to that of various momentum subtraction renormalization schemes at three-loop order. With

A. J. Buras, P. Gambino, M. Gorbahn, S. Jager

We make the simple observation that there exists a universal unitarity triangle for all models, like the SM, the Two Higgs Doublet Models I and II and the MSSM with minimal flavour violation, that do not have any new operators beyond those present in the SM and in which all flavour changing transitions are governed by the CKM matrix with no new phases beyond