August 2000 arXiv papers — page 22

Ulf-G. Meißner

I summarize the theoretical predictions for the spin-dependent nucleon polarizabilities based on chiral effective field theory approaches.

Dmitri Melikhov, Nikolai Nikitin

We analyse the corrections to factorization for the $B-\bar B$ mixing amplitude assuming that non-factorizable soft gluon exchanges can be described by the local gluon condensate. Within this approximation the $<α_s GG>$-correction to the mixing amplitude can be expressed through the $B$-meson transition form factors at zero momentum transfer. The correction

V. S. Fadin, R. Fiore, M. I. Kotsky, A. Papa

We reformulate the so-called ``strong bootstrap&#39;&#39; conditions for the gluon Reggeization in the next-to-leading approximation (NLA), firstly suggested by Braun and Vacca, using a different approach, which is not based on properties of the eigenstates of the NLA octet BFKL kernel. We write the second strong bootstrap condition for the NLA octet impact

Asmita Mukherjee

Utilizing the kinematical boost in light-front formalism one can address the issue of relativistic spin operators in an arbitrary reference frame. In the gauge $A^+=0$, the interaction dependent transverse spin operators can be separated into three parts. In analogy with the helicity sum rule, we propose a transverse spin sum rule. We perform a one loop reno

I. M. Dremin, J. Tran Thanh Van

The solution of the equations for the generating functions of multiplicity distributions of quark and gluon jets in higher order 3NLO perturbative QCD is obtained. The non-perturbative effects are discussed as well. The results are compared to recent experimental data on mean multiplicities, their ratio and its slope, higher moments of the distributions.

A. Kirk

A study of resonance production in central pp collisions is presented as a function of several kinematical variables. In particular the difference in the transverse momentum (dPT) of the exchanged particles shows that undisputed qqbar mesons are suppressed at small dPT whereas glueball candidates are enhanced and in addition, the azimuthal angle phi gives in

T. Bakeyev, Ph. de Forcrand

We present an exact Monte Carlo algorithm designed to sample theories where the energy is a sum of many couplings of decreasing strength. Our algorithm, simplified from that of L. Lin et al. hep-lat/9905033, avoids the computation of almost all non-leading terms. We illustrate its use by simulating SU(2) lattice gauge theory with a 5-loop action, and discuss

Adam D. Helfer

Hawking&#39;s prediction of black-hole evaporation depends on the application of known physics to fantastically high energies -- well beyond the Planck scale. Here, I show that before these extreme regimes are reached, another physical effect will intervene: the quantum backreaction on the collapsing matter and its effect on the geometry through which the qu

Yuri N. Obukhov

Following recent studies of Ford, we suggest -- in the framework of general relativity -- an inflationary cosmological model with the self-interacting spinning matter. A generalization of the standard fluid model is discussed and estimates of the physical parameters of the evolution are given.

Yuri N. Obukhov

A hyperfluid is a classical continuous medium carrying hypermomentum. We modify the earlier developed variational approach to a hyperfluid in such a way that the Frenkel type constraints imposed on the hypermomentum current are eliminated. The resulting self-consistent model is different from the Weyssenhoff type one. The essential point is a conservation of

Yuri N. Obukhov, Romualdo Tresguerres

A variational theory of a continuous medium is developed the elements of which carry momentum and hypermomentum (hyperfluid). It is shown that the structure of the sources in metric-affine gravity is predetermined by the conservation identities and, when using the Weyssenhoff ansatz, these explicitly yield the hyperfluid currents.

Stephan Busemann

Constraint-based grammars can, in principle, serve as the major linguistic knowledge source for both parsing and generation. Surface generation starts from input semantics representations that may vary across grammars. For many declarative grammars, the concept of derivation implicitly built in is that of parsing. They may thus not be interpretable by a gene

Parameswaran Gopikrishnan, Vasiliki Plerou, Xavier Gabaix, H. Eugene Stanley

We quantitatively investigate the ideas behind the often-expressed adage `it takes volume to move stock prices&#39;, and study the statistical properties of the number of shares traded $Q_{Δt}$ for a given stock in a fixed time interval $Δt$. We analyze transaction data for the largest 1000 stocks for the two-year period 1994-95, using a database that record

J. Hove, S. Mo, A. Sudbo

The geometric properties of the critical fluctuations in abelian gauge theories such as the Ginzburg-Landau model are analyzed in zero background field. Using a dual description, we obtain scaling relations between exponents of geometric and thermodynamic nature. In particular we connect the anomalous scaling dimension $η$ of the dual matter field to the Hau

B. Kahng, H. Jeong, A. -L. Barabasi

Recently it was experimentally demonstrated that sputtering under normal incidence leads to the formation of spatially ordered uniform nanoscale islands or holes. Here we show that these nanostructures have inherently nonlinear origin, first appearing when the nonlinear terms start to dominate the surface dynamics. Depending on the sign of the nonlinear term

RC Ball, G Caldarelli, A Flammini

We formulate the angular structure of Lacunarity in fractals, in terms of a symmetry reduction of the three point correlation function. This provides a rich probe of universality, and first measurements yield new evidence in support of the equivalence between self-avoiding walks and percolation perimeters in two dimensions. We argue the Lacunarity reveals mu

V. B. Braginsky, M. L. Gorodetsky, S. P. Vyatchanin

Thermodynamical fluctuations of temperature in mirrors of gravitational wave antennae may be transformed into additional noise not only through thermal expansion coefficient but also through temperature dependence of refraction index. The intensity of this noise is comparable with other known noises and must be taken into account in future steps of the anten

D. Rideau, P. Monceau, R. Currat, H. Requardt

Using high-resolution X-ray scattering techniques, we measure the variation, q(x), of the position in reciprocal space of the CDW satellite, in the sliding state, along the length of NbSe_3 whiskers. We show that structural defects and intentionally X-ray radiation-damaged regions increase locally the CDW pinning force, and induce CDW phase distortions which

V. V. Konotop, V. Kuzmiak

In a one-dimensional periodic nonlinear $χ^{(2)}$ medium, by choosing a proper material and geometrical parameters of the structure, it is possible to obtain two matching conditions for simultaneous generation of second and third harmonics. This leads to new diversity of the processes of the resonant three-wave interactions, which are discussed within the fr

M. Kastner, M. Promberger

Typically, in order to obtain finite-size scaling laws for quantities in the microcanonical ensemble, an assumption is taken as a starting point. In this paper, consistency of such a Microcanonical Finite-Size Scaling Assumption with its commonly accepted canonical counterpart is shown, which puts Microcanonical Finite-Size Scaling on a firmer footing.

J. B. Philipp, C. Hoefener, S. Thienhaus, J. Klein

We performed a systematic analysis of the tunneling magnetoresistance (TMR) effect in single grain boundary junctions formed in epitaxial La(2/3)Ca(1/3)MnO(3) films deposited on SrTiO(3) bicrystals. For magnetic fields H applied parallel to the grain boundary barrier, an ideal two-level resistance switching behavior with sharp transitions is observed with a

Jean-Philippe Bouchaud

We discuss several models in order to shed light on the origin of power-law distributions and power-law correlations in financial time series. From an empirical point of view, the exponents describing the tails of the price increments distribution and the decay of the volatility correlations are rather robust and suggest universality. However, many of the mo

I. N. Remediakis, Efthimios Kaxiras, P. C. Kelires

We study the thermodynamics of C incorporation on Si(100), a system where strain and chemical effects are both important. Our analysis is based on first-principles atomistic calculations to obtain the important lowest energy structures, and a classical effective Hamiltonian which is employed to represent the long-range strain effects and incorporate the ther

E. Courtens, B. Hehlen, E. Farhi, A. K. Tagantsev

Optical mode crossing is not a plausible explanation for the new broad Brillouin doublet nor for the strong acoustic anomalies observed at low temperatures in SrTiO3. Data presented to support that explanation are also inconclusive.

I. Ichinose, T. Matsui

In a recent Letter, Nayak argued that slave partices are always confined in gauge theories of strongly-correlated electron systems like the t-J model. The argument mostly relies on Elitzur&#39;s theorem and the fact that the effective gauge theory under discussion is at infinite coupling. On the other hand, in the previous papers we studied dynamics of the g

Min-Fong Yang, Shih-Jye Sun, Ming-Che Chang

In this comment, we emphasize that the self-consistent spin wave theory in a recent paper [J. K&#34;onig, H.-H. Lin, and A. H. MacDonald, Phys. Rev. Lett. 84, 5628 (2000)] leads to incorrect results both at low temperatures and near T_c. Thus we suggest another self-consistent spin wave approximation to remedy these flaws.

P. V. Komissinski, E. Il&#39;ichev, G. A. Ovsyannikov, S. A. Kovtonyuk

We probe directly the superconducting current-phase relations (CPR) of Nb/Au/(001) YBa2Cu3Ox heterojunctions prepared in epitaxial c-axis oriented YBa2Cu3Ox (YBCO) thin films. The measurements are performed by a single-junction interference experiment. Atomic Force Microscope observations and estimations made from I-V characteristics confirm the c-axis curre

M. J. Church, M. Balucinska-Church

withdrawn until accepted by the journal

Mark A. Walker

Several lines of evidence suggest that cold, dense gas clouds make a substantial contribution to the total mass of dark halos. If so then physical collisions between clouds must occur; these cause strong, radiative shocks to propagate through the cold gas, with the startling implication that all ``dark&#39;&#39; halos must be luminous. The expected luminosit

Johann A. Hibschman, Jonathan Arons

We re-examine the characteristic polarization angle sweep of rotation-powered pulsars and calculate the expected deviations from this sweep caused by aberrational effects and by polar-cap current flow. We find that in addition to the previously known phase shift of the entire sweep by $ΔΦ= -4 r/R_L$, aberration shifts the polarization angle itself by $ΔΨ= -(

Raj K. Jain, Charles D. Bailyn, Jerome A. Orosz, Jeffrey E. McClintock

We report optical monitoring of the soft X-ray transient XTE J1550-564 during the 1999 season (4 January 1999 to 24 August 1999). The first optical observations available in 1999 show that the peak ``re-flare&#39;&#39; brightness had exceeded the peak brightness of the initial optical flare in September 1998 by over half a magnitude. We compare the optical r

Yu Gao, J. D. Goldader, E. R. Seaquist, Cong Xu

We present our preliminary BIMA CO(1-0) images of II~Zw~96 which show huge molecular gas concentrations outside the merging disks. The dominant extra-disk CO concentrations in II~Zw~96 correspond to the two star-forming ``knots&#39;&#39; hidden by dust, whereas the others are associated with the two spiral disks. The unique huge CO concentrations, $\approxgt

Pasquale Blasi

There is compelling evidence that at least some clusters of galaxies are powerful sources of non-thermal radiation. In all cases where this radiation has been detected, a general trend is that high energy densities of cosmic rays and correspondingly low values of the average magnetic field are required in order to have a self-consistent picture of the multiw

Yu Gao, Cong Xu

We present the first interferometric evidence of CO(1-0) emission in the intragroup starburst (IGS) region of HCG~92 (Stephan&#39;s Quintet). BIMA&#39;s large primary beam covers fully both the IGS region and the dominant group member galaxy Seyfert NGC 7319, as well as partially the intruder galaxy NGC 7318B. CO emission of $\approxgt 4σ$ is detected in all

Benjamin D. Wandelt, Eric Hivon, Krzysztof M. Gorski

As the era of high precision cosmology approaches, the empirically determined power spectrum of the microwave background anisotropy $C_l$ will provide a crucial test for cosmological theories. We present an exact semi-analytic framework for the study of the ampling statistics of the $C_l$ resulting from observations with partial sky coverage and anisotropic

M. -A. Miville-Deschenes, F. Boulanger, A. Abergel, J. -P. Bernard

We present new data processing techniques that allow to correct the main instrumental effects that degrade the images obtained by ISOCAM, the camera on board the Infrared Space Observatory (ISO). Our techniques take advantage of the fact that a position on the sky has been observed by several pixels at different times. We use this information (1) to correct

L. Pasquini, J. R. de Medeiros, L. Girardi

(Abridged) Ca II H and K high resolution observations for 60 evolved stars in the field and in 5 open clusters are presented. From these spectra chromospheric fluxes are derived, and a homogeneous sample of more than 100 giants is built adding data from the literature. In addition, for most stars, rotational velocities were derived from CORAVEL observations.

Gentaro Watanabe, Kei Iida, Katsuhiko Sato

Geometrical structure of matter at subnuclear densities is investigated in the presence of a degenerate gas of neutrinos as encountered in stellar collapse. The crystalline phases with spherical, cylindrical and planar nuclei as well as with spherical and cylindrical nuclear bubbles are considered by using a compressible liquid-drop model. This model allows

Giovanni Amelino-Camelia, Tsvi Piran

One of the most puzzling current experimental physics paradoxes is the arrival on Earth of Ultra High Energy Cosmic Rays with energies above the GZK threshold. The recent observation of 20TeV photons from Mk 501 is another somewhat similar paradox. Several models have been proposed for the UHECR paradox. No solution has yet been proposed for the TeV-$γ$ para

Yuri N. Obukhov

An overview of the cosmological models with expansion, shear and rotation is presented. Problems of the rotating models are discussed, their general kinematic properties and dynamical realizations are described. A particular attention is paid to the discussion of possible observational effects which could be used to estimate or to put limits on the cosmic ro

Y. P. Wang, P. L. Biermann, A. Wandel

A mass correlation of central black holes and their spheroids ~0.002(within a factor of three) is suggested by Hubble Space Telescope (HST) and various ground-based CCD photometries of early type galaxies. The near-IR images of quasar hosts and the emission line measurements of Broad Line Region for bright QSOs present a similar correlation, which supports t

N. Hayashida, K. Honda, N. Inoue, K. Kadota

After our Ap.J. publication of the Akeno Giant Air Shower Array (AGASA) results in 1999 (Takeda et al., 1999), we observed nine events with energies above 4 $\times$ 10$^{19}$eV until May 2000. This short report lists the coordinates of these events, and shows the updated energy spectrum and arrival direction map. The analysis was carried out with the same p

Houri Ziaeepour

If CDM particles decay and their lifetime is comparable to the age of the Universe, they can modify its equation of state. By comparing the results of numerical simulations with high redshift SN-Ia observations we show that this hypothesis is consistent with present data. Fitting the simplest quintessence models with constant $w_q$ to data leads to $w_q \les

A. Kucinskas, V. Vansevicius, M. Sauvage, T. Tanabé

We present a brief summary of the ISO survey of AGB stars in 8 populous intermediate age clusters of the Magellanic Clouds. Totally, more than 100 AGB and RGB stars were observed at 4.5, 6.7 and 12 $μ$m. We introduce a new method to estimate effective temperatures of oxygen-rich AGB stars, and derive precise bolometric magnitudes and effective temperatures f

S. T. Bramwell, J. -Y. Fortin, P. C. W. Holdsworth, S. Peysson

We study the probability density function for the fluctuations of the magnetic order parameter in the low temperature phase of the XY model of finite size. In two-dimensions this system is critical over the whole of the low temperature phase. It is shown analytically and without recourse to the scaling hypothesis that, in this case, the distribution is non-G

Axel Brandenburg, John Hazlehurst

The buoyant rise of thermals (i.e. bubbles of enhanced entropy, but initially in pressure equilibrium) is investigated numerically in three dimensions for the case of an adiabatically stratified layer covering 6-9 pressure scale heights. It is found that these bubbles can travel to large heights before being braked by the excess pressure that builds up in or

Atsuo Kuniba, Tomoki Nakanishi

We study a family of power series characterized by a system of recursion relations (Q-system) with a certain convergence property. We show that the coefficients of the series are expressed by the numbers which formally count the off-diagonal solutions of the U_q(X^{(1)}_n) Bethe equation at q=0. The series are conjectured to be the X_n-character of a certain

Gia Dvali, Gregory Gabadadze

We generalize the mechanism proposed in [hep-th/0005016] and show that a four-dimensional relativistic tensor theory of gravitation can be obtained on a delta-function brane in flat infinite-volume extra space. In particular, we demonstrate that the induced Ricci scalar gives rise to Einstein&#39;s gravity on a delta-function type brane if the number of spac

Mitsuhiro Kawasaki

The experimental time scale dependence of thermodynamic relations in out-of-equilibrium systems with aging phenomena is investigated theoretically by using only aging properties of the two-time correlation functions and the generalized fluctuation-dissipation theorem (FDT). We show that there are two experimental time regimes characterized by different therm

P. Deuar, W. J. Munro

While it is known that copying a quantum system does not increase the amount of information obtainable about the originals, it may increase the amount available in practice, when one is restricted to imperfect measurements. We present a detection scheme which using imperfect detectors, and possibly noisy quantum copying machines (that entangle the copies), a

Jean-Luc Brylinski

We study the rank of a general tensor $u$ in a tensor product $H_1\ot...\ot H_k$. The rank of $u$ is the minimal number $p$ of pure states $v_1,...,v_p$ such that $u$ is a linear combination of the $v_j$&#39;s. This rank is an algebraic measure of the degree of entanglement of $u$. Motivated by quantum computation, we completely describe the rank of an arbit

TRIUMF Munoic Hydrogen Collaboration, M. C. Fujiwara, A. Adamczak, J. M. Bailey

Resonant formation of $dμt$ molecules in collisions of muonic tritium ($μt$) on D$_2$ was investigated using a beam of $μt$ atoms, demonstrating a new direct approach in muon catalyzed fusion studies. Strong epithermal resonances in $dμt$ formation were directly revealed for the first time. From the time-of-flight analysis of $2036\pm 116$ $dt$ fusion events

Xufeng Liu, Changpu Sun

Two restricted $C[q,q^{-1}]-$forms of the well known q-boson algebra are introduced and the corresponding restricted q-Fock spaces defined. All of the irreducible highest weight representations, including the infinite dimensional ones, of $U_ε^{res}(sl_2)$ of type 1 are constructed through the restricted q-Fock spaces.

Eleanor G. Rieffel

This paper is a more succinct version of the author&#39;s 1993 UCLA mathematics thesis. It proves that any group quasi-isometric to the product of the hyperbolic plane with the real line is a finite extension of a cocompact lattice in either the isometry group of the product of the hyperbolic plane with the real line or the isometry group of the universal co

Ichiro Oda

We investigate the possibility of having the electrically charged Reissner-Nordstrom black hole in the gravity localized models in a brane world. It is shown that the Reissner-Nordstrom black hole exists as a solution in the 5D Randall-Sundrum domain wall model if there is the U(1) bulk gauge field. We find that the charged black hole is localized on a 3-bra

Sung-Won Lee

First inclusive measurements of isolated prompt photons in photoproduction at HERA have been made with the ZEUS detector. Cross sections are given as a function of the pseudorapidity and the transverse energy of the photon, for E_T^gamma > 5 GeV in the gamma-p centre-of-mass energy range 134-285 GeV. Comparisons are made with predictions from LO Monte Carlo

E. Buks, M. L. Roukes

Electrostatic and Casimir interactions limit the range of positional stability of electrostatically-actuated or capacitively-coupled mechanical devices. We investigate this range experimentally for a generic system consisting of a doubly-clamped Au suspended beam, capacitively-coupled to an adjacent stationary electrode. The mechanical properties of the beam

Kazumi Maki, Stephan Haas

Recent experiments on Sr_2RuO_4 have indicated the presence of linear nodes in the superconducting order parameter. Among the possible spin triplet states, 2D p-wave superconductivity with E_u symmetry appears to be inconsistent with the experiments, whereas the 2D f-wave order parameter with B_1g x E_u symmetry turns out to be a more likely candidate. Here

Kazusumi Ino

We study the behavior of the persistent edge current for paired quantum Hall states on the cylinder. We show that the currents are periodic with the unit flux $ϕ_0=hc/e$. At low temperatures, they exhibit anomalous oscillations in their flux dependence.The shape of the functions converges to the sawtooth function periodic with $ϕ_0/2$.

Y. Paltiel, E. Zeldov, Y. Myasoedov, M. L. Rappaport

Transport studies in a Corbino disk geometry suggest that the Bragg glass phase undergoes a first-order transition into a disordered solid. This transition shows a sharp reentrant behavior at low fields. In contrast, in the conventional strip configuration, the phase transition is obscured by the injection of the disordered vortices through the sample edges,

E. Balkovsky, G. Falkovich, A. Fouxon

We consider inertial particles suspended in an incompressible turbulent flow. Due to inertia of particles, their velocity field acquires small compressible component. Its presence leads to a new qualitative effect --- possibility of clustering. We show that this effect is significant for heavy particles, leading to strong fluctuations of the concentration.

A. Kucinskas, V. Vansevicius, M. Sauvage, T. Tanabé

We present ISO (Infrared Space Observatory) observations of the planetary nebula Lindsay 305 (L 305) in the Small Magellanic Cloud. L 305 is very prominent in the ISOCAM frames at 6.75 and 11.5 $μ$m, although it is under the detection limit at 4.5 $μ$m. The obtained spectral energy distribution shows a strong mid-IR excess, which, depending on the amount of

Cristina C. Popescu, Angelos Misiriotis, Nikolaos D. Kylafis, Richard J. Tuffs

We describe a new tool for the analysis of the UV to the sub-millimeter (sub-mm) spectral energy distribution (SED) of spiral galaxies. We use a consistent treatment of grain heating and emission, solve the radiation transfer problem for a finite disk and bulge, and self-consistently calculate the stochastic heating of grains placed in the resulting radiatio

E. V. Gotthelf, G. Vasisht, M. Boylan-Kolchin, K. Torii

Since their discovery 30 years ago, pulsars have been understood to be neutron stars (NSs) born rotating rapidly (~ 10-100 ms). These neutron stars are thought to be created in supernova explosions involving massive stars, which give rise to expanding supernova remnants (SNRs). With over 220 Galactic SNRs known (Green 1998) and over 1200 radio pulsars detect

Kirk T. McDonald

The group velocity for pulses in an optical medium can be negative at frequencies between those of a pair of laser-pumped spectral lines. The gain medium then can amplify the leading edge of a pulse resulting in a time advance of the pulse when it exits the medium, as has been recently demonstrated in the laboratory. This effect has been called superluminal,

Robert de Mello Koch, Joao P. Rodrigues

The ratios of the masses of D(p-d) branes to the masses of Dp in open bosonic string field theory are computed within the modified level truncation approximation of Moeller, Sen and Zweibach. At the lowest non-trivial truncation requiring the addition of new primary states, we find evidence of rapid convergence to the expected result for 1<d<7 providing addi

Howard L. Richards, T. L. Einstein

The so-called generalized Wigner distribution has earlier been shown to be an excellent approximation for the terrace width distribution (TWD) of vicinal surfaces characterized by step-step interactions that are perpendicular to the average step direction and fall off as the inverse square of the step spacing. In this paper we show that the generalized Wigne

G. W. Gibbons, C. A. R. Herdeiro

Fluctuations around a non-trivial solution of Born-Infeld theory have a limiting speed given not by the Einstein metric but the Boillat metric. The Boillat metric is S-duality invariant and conformal to the open string metric. It also governs the propagation of scalars and spinors in Born-Infeld theory. We discuss the potential clash between causality determ

W. D. Heiss, R. G. Nazmitdinov

The self-consistent harmonic oscillator model including the three-dimensional cranking term is extended to describe collective excitations in the random phase approximation. It is found that quadrupole collective excitations associated with wobbling motion in rotating nuclei lead to the appearance of two- or three-dimensional rotation.

Danny Birmingham, Siddhartha Sen

We show that a Rademacher expansion can be used to establish an exact bound for the entropy of black holes within a conformal field theory framework. This convergent expansion includes all subleading corrections to the Bekenstein-Hawking term.

Arvind Raviswaran, Chuan-Pu Liu, David G. Cahill, J. Murray Gibson

This paper withdrawn by the authors due to errors in the TEM measurements of the densities and sizes of small islands.

Masatoshi Imanishi, C. C. Dudley

The energy sources of nine infrared luminous galaxies (IRLGs) are diagnosed based on their ground-based 3--4 $μ$m spectra. Both the equivalent width of the 3.3 $μ$m polycyclic aromatic hydrocarbon (PAH) emission feature and the 3.3 $μ$m PAH to far-infrared luminosity ratio ($L_{3.3}/L_{\rm FIR}$) are analyzed. Assuming nuclear compact starburst activity in t

Andre Lukas, Pierre Ramond, Andrea Romanino, Graham G. Ross

A plausible explanation for the existence of additional light sterile neutrinos is that they correspond to modulini, fermionic partners of moduli, which propagate in new large dimensions. We discuss the phenomenological implications of such states and show that solar neutrino oscillation is well described by small angle MSW oscillation to the tower of Kaluza

Rob Clifton, Hans Halvorson

Philosophical reflection on quantum field theory has tended to focus on how it revises our conception of what a particle is. However, there has been relatively little discussion of the threat to the &#34;reality&#34; of particles posed by the possibility of inequivalent quantizations of a classical field theory, i.e., inequivalent representations of the alge

A. N. Leznov, J. Sanchez Mondragon

It is shown that the Benney system is equivalent to a one body classical dynamical problem in which the interaction potential is a functional of the action function. The general solution of this equation is responsible for the general solution of the Benney system. Some particular solutions of the selfconsistent Hamilton-Jacobi equation arising in this inves

David P. Robbins

An alternating sign matrix is a square matrix satisfying (i) all entries are equal to 1, -1 or 0; (ii) every row and column has sum 1; (iii) in every row and column the non-zero entries alternate in sign. The 8-element group of symmetries of the square acts in an obvious way on square matrices. For any subgroup of the group of symmetries of the square we may

Petr P. Kulish, Vladimir D. Lyakhovsky, Alexander A. Stolin

We show that for some Hopf subalgebras in U_F(so(M)) nontrivially deformed by a twist F it is possible to find the nonlinear primitive copies. This enlarges the possibilities to construct chains of twists. For orthogonal algebra U(so(M)) we present a method to compose the full chains with carrier space as large as the Borel subalgebra B(so(M)). These chains

Wlodzimierz Bryc

We analyze certain stationary fields with linear regressions and quadratic conditional variances. This classic probabilistic problem leads somewhat unexpectedly to stationary Markov processes closely tied to non-commutative probability through the q-Hermite polynomials.

M. Burkardt

The connection between parton distributions as a function of the impact parameter and off-forward parton distributions is discussed in the limit of vanishing skewedness parameter $ξ$, i.e. when the off-forwardness is purely transverse. It is also illustrated how to relate $ξ\neq 0$ data to $ξ=0$ data, which is important for experimental measurements of these

Ernest Ma

In R parity violating supersymmetry (conserving baryon number B but violating lepton number L), Majorana neutrino masses may arise at tree level, in one loop, and in two loops. The L violating interactions work together with the B + L violating electroweak sphalerons to erase any preexisting B or L asymmetry of the Universe. To have successful leptogenesis n

L. Chikovani, T. Djobava

The sensitivity of ATLAS experiment to the top-quark rare decay via flavor- changing neutral currents t \to Zq (q represents c and u quarks) have been studied at \sqrt{s}= 14 TeV in two decay modes: 1. The pure leptonic decay of gauge bosons: t\bar{t} \to ZqWb \to l^{+} l^{-} j l^{+-} nu j_{b} (l=e, mu) 2. The leptonic decay of Z bosons and hadronic decay of

Giovanni Gallavotti

The Luttinger model was introduced to illustrate the theory of Tomonaga via an exactly soluble model. It became soon the subject of great interest also on the part of Mathematical Physics and a key to the investigations of the mathematical properties of Condensed Matter Physics. This paper reviews aspects of the above developments relevant for renormalizatio

Shobhana Narasimhan

The observed anisotropies of surface vibrations for unreconstructed FCC metal (110) surfaces are often reversed from the &#34;common sense&#34; expectation. The source of these reversals is investigated by performing ab initio density functional theory calculations to obtain the surface force constant tensors for Ag(110), Cu(110) and Al(110). The most striki

Y. Meurice

We present an analytical method to solve Dyson&#39;s hierarchical model, involving the scaling variables near the high-temperature fixed point. The procedure seems plagued by the presence of small denominators as in perturbative expansions near integrable systems in Hamiltonian mechanics. However, in all cases considered, a zero denominator always comes with

Teruhisa S. Komatsu, Shio Inagaki, Naoko Nakagawa, Satoru Nasuno

We investigate experimentally granular piles exhibiting steady surface flow. Below the surface flow, it has been believed exisitence of a `frozen&#39; bulk region, but our results show absence of such a frozen bulk. We report here that even the particles in deep layers in the bulk exhibit very slow flow and that such motion can be detected at an arbitrary de

Naoko Nakagawa, Kunihiko Kaneko, Teruhisa S. Komatsu

We study relaxational behavior from a highly excited state for a composite system in partial contact with a heat bath, motivated by an experimental report of long-term energy storage in protein molecules. The system consists of two coupled elements: The first element is in direct contact with a heat bath, while the second element interacts only with the firs

Andrew J. Bullen, Keith E. O&#39;Hara, David G. Cahill, Othon Monteiro

Thermal conductivities $Λ$ of amorphous carbon thin films are measured in the temperatures range 80--400 K using the $3ω$ method. Sample films range from soft a-C:H prepared by remote-plasma deposition ($Λ= 0.20$ W m$^{-1}$ K$^{-1}$ at room temperature) to amorphous diamond with a large fraction of $sp^3$ bonded carbon deposited from a filtered-arc source ($

T. Senthil, Matthew P. A. Fisher

This paper is concerned with the idea that the electron is fractionalized in the cuprate high-$T_c$ materials. We show how the notion of topological order may be used to develop a precise theoretical characterization of a fractionalized phase in spatial dimension higher than one. Apart from the fractional particles into which the electron breaks apart, there

Rudy Wijnands

Before the launch of the Rossi X-ray Timing Explorer (RXTE) satellite, the differences in the rapid X-ray variability between the two main types of neutron star binaries (i.e., the Z and atoll sources) could be explained by invoking different mass accretion rates and magnetic field strengths. However, the results obtained with RXTE now show that these system

Ralph Neuhaeuser, Fred M. Walter, Elvira Covino, Juan M. Alcala

We present the ROSAT All-Sky Survey data in a 126 deg^2 area in and around the CrA star forming region. With low-resolution spectroscopy of unidentified ROSAT sources we could find 19 new pre-main sequence stars, two of which are classical T Tauri stars, the others being weak-lined. The spectral types of these new T Tauri stars range from F7 to M6. The two n

O. A. Gress, T. I. Gress, L. V. Pan&#39;kov, Yu. V. Parfenov

Experiment on the study of fluctuation of night glow is conducted on the base of 13 module atmospheric Cherenkov telescope TUNKA-13.Basic task of TUNKA-13 is registration of light from Extended Air Shower (EAS) initiated by primary cosmic particles. Observation of light flashes radiating in nigght atmosphere is one more experiment which is run for TUNKA-13 t

Masatoshi Imanishi

The results of 3-4 $μ$m spectroscopy towards the nuclei of NGC 3094, NGC 7172, and NGC 7479 are reported. In ground-based 8-13 $μ$m spectra, all the sources have strong absorption-like features at $\sim$10 $μ$m, but they do not have detectable polycyclic aromatic hydrocarbon (PAH) emission features. The 3.4 $μ$m carbonaceous dust absorption features are dete

F. Parisi, P. Levy, L. Ghivelder, G. Polla

The effect of low magnetic fields on the transport properties of a manganite compound with magnetic phase separation is studied. The different behavior obtained in samples of La0.5Ca0.5MnO3 related to the way in which the low field is applied is consistent with a picture of changes in the metallic fraction induced by the magnetic field in a field-cooled cycl

Matthias Vojta, Arnd Huebsch, R. M. Noack

We investigate the ground-state phase diagram of the quarter-filled Hubbard ladder with nearest-neighbor Coulomb repulsion V using the Density Matrix Renormalization Group technique. The ground-state is homogeneous at small V, a ``checkerboard&#39;&#39; charge--ordered insulator at large V and not too small on-site Coulomb repulsion U, and is phase-separated

Victor M. Yakovenko, Anatoley T. Zheleznyak

The temperature dependences of the Hall coefficient and electrical resistivity recently measured by Moser et al. [Phys. Rev. Lett. 84, 2674 (2000)] in the quasi-one-dimensional organic conductor (TMTSF)2PF6 are quantitatively compared with our previous theoretical calculations [Synth. Met. 103, 2202 (1999); Eur. Phys. J. B 11, 385 (1999)]. We find a good agr

Ilaria Bonizzoni, Giuseppe Giuliani

Experimental tests on `time dilation&#39; began in 1938 with Ives and Stilwell&#39;s work of the transverse Doppler effect due to atoms in inertial flight. Rossi and Hall (1941) inaugurated the era of fast moving elementary particles that dominated the scene until the discovery of the Mossbauer effect (1957). This discovery suggested the use of photons emitt

Juergen Audretsch, Thomas Konrad, Artur Scherer

The normalized state $\ket{ψ(t)}=c_1(t)\ket{1}+c_2(t)\ket{2}$ of a single two-level system performs oscillations under the influence of a resonant driving field. It is assumed that only one realization of this process is available. We show that it is possible to approximately visualize in real time the evolution of the system as far as it is given by $|c_2(t

B. J. Pearson, J. L. White, T. C. Weinacht, P. H. Bucksbaum

We have constructed an automated learning apparatus to control quantum systems. By directing intense shaped ultrafast laser pulses into a variety of samples and using a measurement of the system as a feedback signal, we are able to reshape the laser pulses to direct the system into a desired state. The feedback signal is the input to an adaptive learning alg

Tim Roemer

In this paper we prove parts of a conjecture of Herzog giving lower bounds on the rank of the free modules appearing in the linear strand of a graded $k$-th syzygy module over the polynomial ring. If in addition the module is $\mathbb{Z}^n$-graded we show that the conjecture holds in full generality. Furthermore, we give lower and upper bounds for the graded

Gaspare Carbone, Mauro Carfora, Annalisa Marzuoli

In this paper we present classes of state sum models based on the recoupling theory of angular momenta of SU(2) (and of its q-counterpart $U_q(sl(2))$, q a root of unity). Such classes are arranged in hierarchies depending on the dimension d, and include all known closed models, i.e. the Ponzano-Regge state sum and the Turaev-Viro invariant in dimension d=3,