December 2000 arXiv papers — page 14

Antonio Scala, Nikolay V. Dokholyan, Sergey V. Buldyrev, H. Eugene Stanley

We introduce a quantity, the entropic susceptibility, that measures the thermodynamic importance-for the folding transition-of the contacts between amino acids in model proteins. Using this quantity, we find that only one equilibrium run of a computer simulation of a model protein is sufficient to select a subset of contacts that give rise to the peak in the

R. Manzke, R. Mueller, C. Janowitz, M. Schneider

Angle-resolved photoemission spectroscopy is performed on single crystals of the single-layer high-Tc superconductor Bi(2)Sr(2-x)La(x)CuO(6+d) at optimal doping (x=0.4) in order to study in great detail the Zhang-Rice (ZR) singlet band at the Fermi level. Besides the high crystal quality the advantages of a single-layer material are the absence of bilayer ef

A. E. Allahverdyan, Th. M. Nieuwenhuizen

A known aspect of the Clausius inequality is that an equilibrium system subjected to a squeezing $\d S$ of its entropy must release at least an amount $|\dbarrm Q|=T|\d S|$ of heat. This serves as a basis for the Landauer principle, which puts a lower bound $T\ln 2$ for the heat generated by erasure of one bit of information. Here we show that in the world o

Tooru Taniguchi

By applying the Kramers-Kronig dispersion relation to the transmission amplitude a direct connection of the conductance with the density of states is given in quantum scattering systems connected to two one-channel leads. Using this method we show that in the Fano resonance the peak position of the density of states is generally different from the position o

S. Banerjee, R. B. Griffiths, M. Widom

We examine the thermodynamic limit of fluids of hard core particles that are polydisperse in size and shape. In addition, particles may interact magnetically. Free energy of such systems is a random variable because it depends on the choice of particles. We prove that the thermodynamic limit exists with probability 1, and is independent of the choice of part

S. Banerjee, R. B. Griffiths, M. Widom

We prove existence of a shape and boundary condition independent thermodynamic limit for fluids and solids of identical particles with electric or magnetic dipole moments. Our result applies to fluids of hard core particles, to dipolar soft spheres and Stockmayer fluids, to disordered solid composites, and to regular crystal lattices. In addition to their pe

D. E. Angelescu, R. N. Bhatt

The magnetic interaction of a pair of bound magnetic polarons (BMP) in diluted magnetic semiconductors (DMS) is analyzed via a generalized Hubbard-type Hamiltonian for two carriers in the presence of effective magnetic fields arising from the magnetic polarization of their respective polarons. For the case where the magnetic fields at the two sites have equa

A. Langari, M. A. Martin-Delgado

We study numerically the formation of magnetization plateaux with the Lanczos method in 2-leg ladders with mixed spins of magnitudes $(S_1,S_2)=(1,1/2)$ located at alternating positions along the ladder and with dimerization $γ$. For interchain coupling $J'>0$ and $γ=0$, we find normalized plateaux at $m=1/3$ starting at zero field and $m=1$ (saturation)

C. Mischler, J. Baschnagel, K. Binder

This paper reviews recent Monte Carlo simulation studies of the glassy behavior in thin polymer films. The simulations employ a version of the bond-fluctuation lattice model, in which the glass transition is driven by the competition between a stiffening of the polymers and their dense packing in the melt. The melt is geometrically confined between two impen

M. Hart, P. Jefferies, N. F. Johnson, P. M. Hui

We show analytically how the fluctuations (i.e. standard deviation) in the Minority Game (MG) can decrease below the random coin-toss limit if the agents use more general, stochastic strategies. This suppression of the standard deviation results from a cancellation between the actions of a crowd, in which agents act collectively and make the same decision, a

Bryan Gaensler

In this brief review, I discuss recent developments in the study of pulsar-powered nebulae ("plerions"). The large volume of data which has been acquired in recent years reveals a diverse range of observational properties, demonstrating how differing environmental and pulsar properties manifest themselves in the resulting nebulae.

R. J. Brunner

A virtual observatory will not only enhance many current scientific investigations, but it will also enable entirely new scientific explorations due to both the federation of vast amounts of multiwavelength data and the new archival services which will, as a necessity, be developed. The detailing of specific science use cases is important in order to properl

Mitchell C. Begelman

We show that magnetized, radiation dominated atmospheres can support steady state patterns of density inhomogeneity that enable them to radiate at far above the Eddington limit, without suffering mass loss. The inhomogeneities consist of periodic shock fronts bounding narrow, high-density regions, interspersed with much broader regions of low density. The ra

N. M. McClure-Griffiths, John M. Dickey, B. M. Gaensler, A. J. Green

We present preliminary results from the Southern Galactic Plane Survey (SGPS) Test Region and Parkes data. As part of the pilot project for the Southern Galactic Plane Survey, observations of a Test Region (325.5 deg < l < 333.5 deg; -0.5 deg < b < 3.5 deg) were completed in December 1998. Single dish observations of the full survey region (253 deg < l < 358

Claus Leitherer, Joao Leao, Tim Heckman, Daniel Lennon

We present synthetic ultraviolet spectra of metal-poor star-forming galaxies which were calculated with the Starburst99 package. A new spectral library was generated from HST observations of O stars in the Large and Small Magellanic Clouds. The corresponding mean metallicity of the synthetic spectra is approximately 1/4\Zs. The spectra have a resolution of 1

Paolo Padovani, Paolo Giommi

We present the results of our methods to &#34;mine&#34; the blazar sky, i.e., select blazar candidates with very high efficiency. These are based on the cross-correlation between public radio and X-ray catalogs and have resulted in two surveys, the Deep X-ray Radio Blazar Survey (DXRBS) and the &#34;Sedentary&#34; BL Lac survey. We show that data mining is v

H. Landt, P. Padovani, E. Perlman, P. Giommi

We have searched the archived, pointed ROSAT Position Sensitive Proportional Counter data for blazars by correlating the WGACAT X-ray database with several publicly available radio catalogs, restricting our candidate list to serendipitous X-ray sources with a flat radio spectrum (alpha_r <= 0.70). This makes up the Deep X-ray Radio Blazar Survey (DXRBS). Her

Paolo Padovani

I address the need for deep blazar surveys by showing that our current understanding of blazars is based on a relatively small number of intrinsically luminous sources. I then review the on-going deeper surveys, addressing in particular their limits and limitations. Finally, I present some preliminary results on the evolutionary properties of faint blazars a

D. Hunter, M. Kaufman, D. Hollenbach, R. Rubin

We present mid-infrared imaging and far-infrared (FIR) spectroscopy of 5 IBm galaxies observed by ISO as part of our larger study of the inter- stellar medium of galaxies. Most of the irregulars in our sample are very actively forming stars. The mid-infrared imaging was in a band centered at 6.75 microns that is dominated by polycyclic aromatic hydrocarbons

D. Steeghs

I review the observational evidence for spiral structure in the accretion discs of cataclysmic variables (CVs). Doppler tomography is ideally suited to resolve and map such co-rotating patterns and allows a straightforward comparison with theory. The dwarf nova IP Pegasi presents the best studied case, carrying two spiral arms in a wide range of emission lin

R. C. Vermeulen

WSRT observations have provided a first inventory of the incidence of HI 21 cm line absorption associated with AGN at redshifts up to z=1.0. There is a large range in line depths, from tau=0.44 to tau less than 0.001, and a substantial variety of line profiles, from Gaussians of less than ten km/s to more typically a few hundred km/s, as well as irregular an

V. Caloi

We investigate the consequences of an increase in the envelope helium abundance of pre-helium flash red giants in globular clusters. Comparing predictions with the CM diagrams of a few crucial GC, one finds no evidence for a substantial increase in the surface helium content of HB members of these clusters, at least for objects in the RR Lyrae region or clos

D. M. Worrall, M. Birkinshaw

We present a detailed spectral and spatial analysis of the X-ray properties of the compact and unusual radio galaxy 3C 346, combining information from ROSAT and ASCA. The dominant component of X-ray emission (~ 10^44 ergs/s in each of the 0.5-3 keV and 2-10 keV bands) is unresolved and not heavily absorbed (intrinsic N_H ~< 2 10^21 cm^-2), with evidence for

Kerstin Weis

The nebula around Eta Carinae consists of an inner bipolar structure, historically called the Homunculus, and the outer ejecta consisting mainly of a variety of knots of different sizes.They reach out to distances of up to 30&#34; or0.3pc from Eta Car. With high-resolution long-slit observations we mapped the outer nebula in order to analyze the global expan

N. Neininger

I present a unique data set for the study of molecular gas in galaxies: a complete, high-resolution survey of the CO in M31 and additional local studies. The fully sampled survey has an angular resolution of 23&#34; FWHM and the interferometric data attain the pc-scale with sub-arcsecond resolution. For the first time it is now possible to study large and sm

Jesper Sollerman, Cecilia Kozma, Peter Lundqvist

The Crab nebula is the remnant of supernova 1054 (SN 1054). The progenitor of this supernova has, based on nucleosynthesis arguments, been modeled as an 8-10 solar mass star. Here we point out that the observations of the late light curve of SN 1054, from the historical records, are not compatible with the standard scenario, in which the late time emission i

Lars Bergstrom, Joakim Edsjo, Christofer Gunnarsson

There is mounting evidence that a self-consistent model for particle cold dark matter has to take into consideration spatial inhomogeneities on sub-galactic scales seen, for instance, in high-resolution N-body simulations of structure formation. Also in more idealized, analytic models, there appear density enhancements in certain regions of the halo. We use

Pierluigi Selvelli, Piercarlo Bonifacio

The exceptional resolution of UVES has allowed the detection of weak spectral features and the separation of components in blended lines. The intensities of all of the OIII fluorescence lines produced by the O1, O3 and other channels, including the 5592 Angstrom charge-exchange line, have been measured and their ratios compared with models.

J. W. Fried, B. von Kuhlmann, K. Meisenheimer, H. -W. Rix

We present the B-band luminosity function and comoving space and luminosity densities for a sample of 2779 I-band selected field galaxies based on multi-color data from the CADIS survey. The sample is complete down to I_815 = 22 without correction and with completeness correction extends to I_815=23.0. By means of a new multi-color analysis the objects are c

Masaru Ueno, Jun Yokogawa, Kensuke Imanishi, Katsuji Koyama

We report the ASCA discovery of a new X-ray pulsar, AX J0049-732, in the Small Magellanic Cloud (SMC). The pulse shape is sinusoidal with a barycentric period of 9.1320 +/- 0.0004 s. The X-ray spectrum was fitted by an absorbed power-law model with a photon index of ~0.6 and a column density of ~1.3e22 cm^-2. An unabsorbed flux in the 0.7-10.0 keV was estima

Bon-Chul Koo, Jeonghee Rho, William T. Reach, JaeHoon Jung

We report the discovery of the shocked molecular gas in the supernova remnant HB 21. We derive the physical parameters of the shocked gas from CO J=1-0 and J=2-1 line observations. We discuss the correlation of the shocked molecular gas with the previously detected, shocked atomic gas and the associated infrared emission.

J. M. Bai, Myung Gyoon Lee

In this paper, we collect radio and X-ray observations for most Fanaroff-Riley I (FRI) radio galaxies in the Zirbel-Baum radio galaxy sample, and investigate the distribution of the radio-to-X-ray effective spectral index, $α_{rx}$, to test the unified scheme of BL Lac objects and FRI radio galaxies. It is found that the range of $α_{rx}$ for FRI radio galax

A. V. Zasov, A. V. Khoperskov, N. V. Tyurina

Different ways of the determination of masses of galactic disks, based on the kinematic data, are briefly discussed. The analysis of the rotation curves which reach maximum inside of a disk, and N-body modeling, reproducing the rotation curves and stellar velocity dispersion of real galaxies, enable to conclude that the mass of a disk is usually significantl

Y. Inoue, T. Namba, S. Moriyama, M. Minowa

We have searched for axions which could have been produced in the solar core using an axion helioscope with a 2.3m-long 4T superconducting magnet. Axion mass region up to m_a=0.26eV was newly explored by introducing dispersion-matching gas. Preliminary analysis sets a limit on axion-photon coupling constant to be less than (6.4--9.6)e-10 GeV^{-1} (95%CL) for

V. R. Eke, J. F. Navarro, M. Steinmetz

High-resolution N-body simulations are used to examine the power spectrum dependence of the concentration of galaxy-sized dark matter halos. It is found that dark halo concentrations depend on the amplitude of mass fluctuations as well as on the ratio of power between small and virial mass scales. This finding is consistent with the original results of Navar

Robert G. Crittenden, Priyamvada Natarajan, Ue-Li Pen, Tom Theuns

The distortion field defined by the ellipticities of galaxy shapes projected on the sky can be uniquely decomposed into a gradient and a curl component. If the observed ellipticities are induced by weak gravitational lensing, then the distortion field is curl free. Here we show that, in contrast, the distortion field resulting from intrinsic spin alignments

Thomas Becher, Matthias Neubert, Alexey A. Petrov

We present exact results, at next-to-leading order in renormalization-group improved perturbation theory, for the Wilson coefficients appearing at order 1/m_Q in the heavy-quark expansion of heavy-light current operators. To this end, we complete the calculation of the corresponding two-loop anomalous dimension matrix. Our results are important for determina

Kaustubh Agashe

We review the equivalence of two approaches to study theories with gauge fields in extra spatial dimensions, namely the ``4D'' approach (with KK states) and the ``5D'' approach (with matching to the 4D theory at the compactification scale). In particular, we reiterate that there are two different power-law scalings of ``effective'' gauge couplings. In a supe

Jim Conant, Peter Teichner

We explain the notion of a grope cobordism between two knots in a 3-manifold. Each grope cobordism has a type that can be described by a rooted unitrivalent tree. By filtering these trees in different ways, we show how the Goussarov-Habiro approach to finite type invariants of knots is closely related to our notion of grope cobordism. Thus our results can be

Jinho Baik, Percy Deift, Eric Rains

We obtain an identity between Fredholm determinants of two kinds of operators, one acting on functions on the unit circle and the other acting on functions on a subset of the integers. This identity is a generalization of an identity between a Toeplitz determinant and a Fredholm determinant that has appeared in the random permutation context. Using this iden

Eanna Flanagan, Nicholas Jones, Horace Stoica, S. -H. Henry Tye

We elaborate on the recently proposed static brane world scenario, where the effective 4-D cosmological constant is exponentially small when parallel 3-branes are far apart. We extend this result to a compactified model with two positive tension branes. Besides an exponentially small effective 4-D cosmological constant, this model incorporates a Randall-Sund

Giovanni Amelino-Camelia

I show that it is possible to formulate the Relativity postulates in a way that does not lead to inconsistencies in the case of space-times whose short-distance structure is governed by an observer-independent length scale. The consistency of these postulates proves incorrect the expectation that modifications of the rules of kinematics involving the Planck

D. S. Gorbunov, V. A. Ilyin, V. I. Telnov

In some supersymmetric extensions of the Standard Model fairly light superpartner of t-quark is predicted, which may form bound states - stoponiums. We estimate potentials of TESLA linear collider in search for stoponium, considering the basic e+e- option and the gamma-gamma option (Photon Linear Collider - PLC). It is found that PLC could be the best machin

J. C. Montero, V. Pleitez, M. C. Rodriguez

We build the complete supersymmetric version of a 3-3-1 gauge model using the superfield formalism. We point out that a discrete symmetry, similar to the R-symmetry in the minimal supersymmetric standard model, is possible to be defined in this model. Hence we have both R-conserving and R-violating possibilities. Analysis of the mass spectrum of the neutral

Ian I. Kogan, Dimitri Polyakov

We discuss several closely related concepts in the NSR formulation of superstring theory. We demonstrated that recently proposed NSR model for superstrings on $AdS_5 \times S^5$ is described by the world-sheet logarithmic conformal field theory (LCFT). The origin of LCFT on a world-sheet is closely connected to the matter-ghost mixing in the structure of a b

S. A. Fulling

The eigenvalue density of a quantum-mechanical system exhibits oscillations, determined by the closed orbits of the corresponding classical system; this relationship is simple and strong for waves in billiards or on manifolds, but becomes slightly muddy for a Schrodinger equation with a potential, where the orbits depend on the energy. We discuss several var

M. Sellitto

The aging dynamics and the fluctuation-dissipation relation between the spontaneous diffusion induced by a random noise and the drift motion induced by a small stirring force are numerically investigated in a 3D schematic model of compacting powder: a gravity-driven lattice-gas with kinetic constraints. The compaction dynamics is characterized by a super-agi

Rupert A. C. Croft, David H. Weinberg, Mike Bolte, Scott Burles

We measure the filling factor, correlation function, and power spectrum of transmitted flux in a large sample of Lya forest spectra, comprised of 30 Keck HIRES spectra and 23 Keck LRIS spectra. We infer the linear matter power spectrum P(k) from the flux power spectrum P_F(k), using an improved version of the method of Croft et al. (1998) that accounts for t

Cosmin Macesanu, Lynne H. Orr

We study gluon radiation in top quark production above threshold at high energy $e^+e^-$ colliders. We allow for the top quarks to be off-shell, considering radiation in both the top production and decay processes simultaneously. Our calculation includes all top width effects, spin correlations, and $b$ quark mass effects. We study the effects of gluon radia

E. A. Baltz, J. Silk

We argue that gravitational microlensing is a feasible technique for measuring the mass function of brown dwarf stars in distant galaxies. Microlensing surveys of the bulge of M31, and of M87 in the Virgo cluster, may provide enough events to differentiate the behaviour of the mass function of lenses below the hydrogen burning limit (though we find that M87

F. Atrio-Barandela, J. Einasto, V. Müller, J. P. Mücket

We show that the amplitude of the second acoustic peak in the newly released BOOMERANG-98 and MAXIMA-I data is compatible with the standard primordial nucleosynthesis and with the locally broken-scale-invariant matter power spectrum suggested by recent measurements of the power spectrum in the range $20 - 200$ Mpc. If the slope of matter density perturbation

Mladen Bestvina, Koji Fujiwara

We show that every subgroup of the mapping class group MCG(S) of a compact surface S is either virtually abelian or it has infinite dimensional second bounded cohomology. As an application, we give another proof of the Farb-Kaimanovich-Masur rigidity theorem that states that MCG(S) does not contain a higher rank lattice as a subgroup.

Luigi Pilo, Antonio Riotto

We propose a new higher-dimensional mechanism to localize scalar fields as well as fermionic and gauge fields. The underlying theory is a six-dimensional non-commutative field theory where non-commutativity is allowed along two extra infinite spatial dimensions and the four-dimensional brane is provided by a scalar soliton living in the non-commutative space

Shahn Majid, E. Raineri

Using noncommutative geometry we do U(1) gauge theory on the permutation group $S_3$. Unlike usual lattice gauge theories the use of a nonAbelian group here as spacetime corresponds to a background Riemannian curvature. In this background we solve spin 0, 1/2 and spin 1 equations of motion, including the spin 1 or `photon&#39; case in the presence of sources

Xia-Ji Liu, Hui Hu, Lee Chang, Weiping Zhang

The ground state and its structure for a rotating, harmonically trapped N-Boson system with a weak repulsive contact interaction are studied as the angular momentum L increases up to 3N. We show that the ground state is generally a fragmented condensate due to angular momentum conservation. In response to an (arbitrarily weak) asymmetric perturbation of the

T. M. Aliev, A. Ozpineci, M. Savci

Using the general form of the baryon currents, we calculate the meson-baryon coupling constants and the F/D ratio within the framework of light cone QCD sum rules in the SU(3) flavor symmetry limit. The dependence of the results on the Dirac structure and on the free parameter (b) appearing in the general baryon current is considered. Comparison of our resul

Hideaki Aoyama, Masatoshi Sato, Toshiaki Tanaka

We report general forms of one family of the N-fold supersymmetry in one-dimensional quantum mechanics. The N-fold supersymmetry is characterized by the supercharges which are N-th order in differential operators. The family reported here is defined as a particular form of the supercharges and is referred to as ``type A&#39;&#39;. We show that a quartic and

E. Levin, K. Tuchin

We develop a new approach for solving the non-linear evolution equation in the low $x_B$ region and show that the remarkable &#34;geometric&#34; scaling of its solution holds not only in the saturation region, but in much wider kinematical region. This is in a full agreement with experimental data (Golec-Biernat, Kwiecinski and Stasto).

Vesselin Petkov

At the beginning of the 20th century the classical electron theory (or, perhaps more appropriately, the classical electromagnetic mass theory) - the first physical theory that dared ask the question of what inertia and mass were - was gaining momentum and there were hopes that physics would be finally able to explain their origin. It is argued in this paper

Shoichi Kitamura, Tadashi Kon, Tetsuro Kobayashi

From the point of view of the R-parity breaking supersymmetric model, we propose a scalar top (stop) search with longitudinally polarized electron (e-) and positron(e+) beams which will soon be available at the upgraded HERA. Fully polarized e- or e+ beams could produce the stop two times as much as unpolarized beams, while they increase background events du

Patrick J. Fox

The neutrino pulse from SN1987A provides one of the most rigourous constraints on models of extra dimensions. Previously, calculations have been done to bound the size of these extra dimensions in the case when the metric was factorizable. Here we consider the case of 2 `weakly warped' extra dimensions. We find that even though weak warping seems only to aff

Shadow J. Q. Robinson, Larry Zamick

The effects of setting all T=0 two body interaction matrix elements equal to a constant (or zero) in shell model calculations (designated as $<T=0>=0$) are investigated. Despite the apparent severity of such a procedure, one gets fairly reasonable spectra. We find that using $<T=0>=0$ in single j shell calculations degeneracies appear e.g. the $I={1/2} ^{-}$

G. M. D&#39;Ariano, P. Lo Presti

Quantum operations describe any state change allowed in quantum mechanics, including the evolution of an open system or the state change due to a measurement. In this letter we present a general method based on quantum tomography for measuring experimentally the matrix elements of an arbitrary quantum operation. As input the method needs only a single entang

R. Hasson, D. Richards

It is shown that the energy levels of the one-dimensional nonlinear Schrodinger, or Gross-Pitaevskii, equation with the homogeneous trap potential $x^{2p}$, $p\geq 1$, obey an approximate scaling law and as a consequence the energy increases approximately linearly with the quantum number. Moreover, for a quadratic trap, $p=1$, the rate of increase of energy

G. Vidal, J. I. Cirac

We show how quantum dynamics (a unitary transformation) can be captured in the state of a quantum system, in such a way that the system can be used to perform, at a later time, the stored transformation almost perfectly on some other quantum system. Thus programmable quantum gates for quantum information processing are feasible if some small degree of imperf

Dipankar Home, M K Samal

We show that bipartite entanglements involving non-orthogonal states are {\it necessarily nonmaximally} entangled, however {\it small} the non-orthogonality may be. How the deviation from maximal entanglement is related to nonorthogonality is quantified by using two independent measures of entanglement corresponding to the violation of Bell&#39;s inequality

Mark Dewing

Quantum Monte Carlo (QMC) methods can very accurately compute ground state properties of quantum systems. We applied these methods to a system of boson hard spheres to get exact, infinite system size results for the ground state at several densities. Variational Monte Carlo (VMC) requires optimizing a parameterized wave function to find the minimum energy. W

A. Lukyanov, S. Molokov

Exploding wires are widely used in many experimental setups and pulsed power systems. However, many aspects of the process of wire fragmentation still remain unclear. If the current density is not too high, the wire may break up in the solid state. In a series of papers, see references therein, Graneau argued that neither mechanical vibrations induced by the

Eugenio DelRe, Alessandro Ciattoni, Aharon J. Agranat

The strong asymmetry in charge distribution supporting a single non-interacting spatial needle soliton in a paraelectric photorefractive is directly observed by means of electroholographic readout. Whereas in trapping conditions a quasi-circular wave is supported, the underlying double-dipolar structure can be made to support two distinct propagation modes.

V. Golubnychiy, M. Bonitz, D. Kremp, M. Schlanges

Classical Molecular Dynamics (MD) simulations for a one-component plasma (OCP) are presented. Quantum effects are included in the form of the Kelbg potential. Results for the dynamical structure factor are compared with the Vlasov and RPA (random phase approximation) theories. The influence of the coupling parameter $Γ$, degeneracy parameter $ρΛ^3$ and the f

Alexander A. Vlasov

The Brownian motion of a charged particle with finite size (described by Sommerfeld model) is considered. It is found out that due to radiation reaction: (1) the effective temperature of such particle is lower, and (2) the acceleration of the average velocity is smaller, than that for classical Brown particle without electric charge.

C. Barbieri, W. H. Dickhoff

The Faddeev technique is employed to address the problem of describing the influence of both particle-particle and particle-hole phonons on the single-particle self-energy. The scope of the few-body Faddeev equations is extended to describe the motion of two-hole one-particle (two-particle one-hole) excitations. This formalism allows to sum both particle-par

Jan Toke, W. Udo Schroeder

The importance of quantum effects for exotic nuclear shapes is demonstrated. Based on the example of a sheet of nuclear matter of infinite lateral dimensions but finite thickness, it is shown that the quantization of states in momentum space, resulting from the confinement of the nucleonic motion in the conjugate geometrical space, generates a strong resista

S. Wycech

The nuclear interactions of atomic and low energy antiprotons are studied. Measurements of level shifts and widths in the lightest elements are analyzed and compared with new results obtained in heavy nuclei. Simple geometric properties of antiproton - nucleus interactions are demonstrated. Upon this background one finds some anomalies that indicate strong e

E. Marco, W. Weise

We propose the (gamma,p) reaction as a means of producing possible quasi-bound states of omega mesons in nuclei. We use an effective Lagrangian, based on chiral SU(3) symmetry and vector meson dominance, in order to construct the omega-nuclear potential. The contribution of bound omega states is observable in the missing energy spectra of protons emitted in

A. Amghar, B. Desplanques, L. Theussl

It is known that binding energies calculated from the Bethe-Salpeter equation in ladder approximation can be reasonably well accounted for by an energy-dependent interaction, at least for the lowest states. It is also known that none of these approaches gives results close to what is obtained by using the same interaction in the so-called instantaneous appro

W. Udo Schroeder, Jan Toke

The dynamics of heavy-ion reactions at Fermi energies is dominated by a dissipative mechanism modified by the concurrent emission of non-statistical nucleons, light particles, and nuclear clusters. Experimental observables are available to monitor the relaxation processes driving the evolution of an interacting nuclear system towards equilibrium. Isospin deg

Luca Biferale, Federico Toschi

We present the first measurements of anisotropic statistical fluctuations in perfectly homogeneous turbulent flows. We address both problems of intermittency in anisotropic sectors and hierarchical ordering of anisotropies on a direct numerical simulation of a three dimensional random Kolmogorov flow. We achieved an homogeneous and anisotropic statistical en

Blas Echebarria, Hermann Riecke

Quasipatterns have been found in dissipative systems ranging from Faraday waves in vertically vibrated fluid layers to nonlinear optics. We describe the dynamics of octagonal, decagonal and dodecagonal quasipatterns by means of coupled Ginzburg-Landau equations and study their stability to sideband perturbations analytically using long-wave equations as well

P. Papachristou, F. K. Diakonos, E. Mavrommatis, V. Constantoudis

We study the occurence of delay mechanisms other than periodic orbits in systems with time dependent potentials that exhibit chaotic scattering. By using as model system two harmonically oscillating disks on a plane, we have found the existence of a mechanism not related to the periodic orbits of the system, that delays trajectories in the scattering region.

G. Giachetta, L. Mangiarotti, G. Sardanashvily

We show that non-relativistic and relativistic mechanical systems on a configuration space Q can be seen as the conservative Dirac constraint systems with zero Hamiltonians on different subbundles of the same cotangent bundle T^*Q. The geometric quantization of this cotangent bundle under the vertical polarization leads to compatible covariant quantizations

T. Rador

Using deformations inspired by relativistic considerations and phase space symmetry, we deform the position and momentum operators in one dimension. The resulting algebra is shown to yield the q-oscillator algebra in one limiting case and the q-plane commutation relation in another.

G. S. Asanov

The Finslerian extension of the Euclidean metric is proposed and studied under rigorous conditions that the associated indicatrix is regular and convex. The relativistic pseudo-Euclidean metric is extended, too. The extensions show distinct violation of the $T-$parity, so that the future-past asymmetry of the physical world can stem from the $T-$asymmetry of

A. Stoyanovsky

This paper has been withdrawn due to non-clearness of some technical points, as well as lack of a reasonable statement of quantization conjecture.

Viktor Ostrik

Let $U$ be the quantum group with divided powers in $p-$th root of unity for prime $p$. For any two-sided cell $A$ in the corresponding affine Weyl group one associates tensor ideal in the category of tilting modules over $U$. In this note we show that for any cell $A$ there exists tilting module $T$ from the corresponding tensor ideal such that biggest powe

Vyjayanthi Chari

We define an action of the braid group (associated with a simple Lie algebra) on the space of $n$-tuples of power series in an indeterminate u, with constant term zero. Using this, we give a sufficient condition for a tensor product of finite-dimensional representations of quantum affine algebras to be cyclic on the tensor product of highest weight vectors.

Falleh R. Al-Solamy, Edwin J. Beggs

This paper considers a generalisation of the idea of a Hopf algebra in which a commutative ring replaces the field in the unit and counit. It is motivated by an example from the inverse scattering formalism for solitons. We begin with the corresponding idea for groups, where the concept of the identity is altered.

A. Aslanyan, E. B. Davies

We study the Laplace operator subject to Dirichlet boundary conditions in a two-dimensional domain that is one-to-one mapped onto a cylinder (rectangle or infinite strip). As a result of this transformation the original eigenvalue problem is reduced to an equivalent problem for an operator with variable coefficients. Taking advantage of the simple geometry w

Anton Alekseev, Eckhard Meinrenken, Chris Woodward

We prove that the linearization functor from the category of Hamiltonian K-actions with group-valued moment maps in the sense of Lu, to the category of ordinary Hamiltonian K-actions, preserves products up to symplectic isomorphism. As an application, we give a new proof of the Thompson conjecture on singular values of matrix products and extend this result

Ron M. Adin, Francesco Brenti, Yuval Roichman

We introduce and study three new statistics on the hyperoctahedral group $B_{n}$, and show that they give two generalizations of Carlitz&#39;s identity for the descent number and major index over $S_{n}$. This answers a question posed by Foata.

Ruslan Sharipov

The system of weak normality equations constitutes a part in the complete system of normality equations. Solutions of each of these two systems of equations are associated with some definite classes of Newtonian dynamical systems in Riemannian manifolds. In this paper for the case of simplest flat Riemannian manifold $M=\Bbb R^n$ with $n\geq 3$ we show that

Mario J. Edmundo

The first papers on o-minimal structures appeared in the mid 1980s, since then the subject has grown into a wide ranging generalisation of semialgebraic, subanalytic and subpfaffian geometry. In these notes we try to show that this is in fact the case by presenting several examples of o-minimal structures and by listing some geometric properties of sets and

Herbert Clemens, Christopher Hacon

This paper reproves a general form of the Green-Lazarsfeld &#39;generic vanishing&#39; theorem and more recent strengthenings, as well as giving some new applications.

Andrea Posilicano

Given a self-adjoint operator $A:D(A)\subseteq\calH\to\calH$ and a continuous linear operator $τ:D(A)\to\X$ with Range$ τ&#39;\cap\calH&#39; ={0}$, $\X$ a Banach space, we explicitly construct a family $A^τ_Θ$ of self-adjoint operators such that any $A^τ_Θ$ coincides with the original $A$ on the kernel of $τ$. Such a family is obtained by giving a Kre\uın-li

Giampiero Esposito

The squared Laplace operator acting on symmetric rank-two tensor fields is studied on a (flat) Riemannian manifold with smooth boundary. Symmetry of this fourth-order elliptic operator is obtained provided that such tensor fields and their first (or second) normal derivatives are set to zero at the boundary. Strong ellipticity of the resulting boundary-value

Richard L. Hall, Wolfgang Lucha, Franz F. Schoeberl

We study the eigenvalues E_{n\ell} of the Salpeter Hamiltonian H = β\sqrt(m^2 + p^2) + vr^2, v>0, β> 0, in three dimensions. By using geometrical arguments we show that, for suitable values of P, here provided, the simple semi-classical formula E = min_{r > 0} {v(P/r)^2 + β\sqrt(m^2 + r^2)} provides both upper and lower energy bounds for all the eigenvalues

P. Pitanga

We present a model for the Dirac magnetic monopole, suitable for the strong coupling regime. The magnetic monopole is static, has charge g and mass M, occupying a volume of radius R ~ O (g^2/M). It is shown that inside each n-monopole there exist infinite multipoles. It is given an analytical proof of the existence of monopole-antimonopole bound state. These

I. Bakas, K. Sfetsos

We review the main algebraic aspects that characterize and determine the domain wall solutions of maximal gauged supergravity in various spacetime dimensions by considering consistent truncations that retain a number of components in the diagonal of the coset space scalar manifold of the theory. Starting from the algebraic classification of domain walls in D

Claudio A. Scrucca, Marco Serone

We present a complete string theory analysis of all mixed gauge, gravitational and target-space anomalies potentially arising in the simplest heterotic Z_N orbifold models, with N odd and standard embedding. These anomalies turn out to be encoded in an elliptic index, which can be easily computed; they are found to cancel through a universal GS mechanism ind

K. Konishi

We discuss questions related to renormalization group and to nonperturbative aspects of non-Abelian gauge theories with N=2 and/or N=1 supersymmetry. Results on perturbative and nonperturbative $β$ functions of these theories are reviewed, and new mechanisms of confinement and dynamical symmetry breaking recently found in a class of $SU(n_c)$, $USp(2n_c)$ an