March 2000 arXiv papers — page 5

Cecilia Clementi, Patricia A. Jennings, Jose' N. Onuchic

The overall structure of the transition state and intermediate ensembles experimentally observed for Dihydrofolate Reductase and Interleukin-1beta can be obtained utilizing simplified models which have almost no energetic frustration. The predictive power of these models suggest that, even for these very large proteins with completely different folding mecha

Cecilia Clementi, Hugh Nymeyer, Jose' Nelson Onuchic

Recent experimental results suggest that the native fold, or topology, plays a primary role in determining the structure of the transition state ensemble, at least for small fast folding proteins. To investigate the extent of the topological control of the folding process, we study the folding of simplified models of five small globular proteins constructed

M. Brownlie, Keith A. Benedict

In this paper we consider the three-particle density correlation function for a fractional quantum Hall liquid. The study of this object is motivated by recent experimental studies of fractional quantum Hall systems using inelastic light scattering and phonon absorption techniques. Symmetry properties of the correlation function are noted. An exact sum-rule

S. F. Liotta, A. Majorana

In this paper the Boltzmann equation describing the carrier transport in a semiconductor is considered. A modified Chapman-Enskog method is used, in order to find approximate solutions in the weakly non-homogeneous case. These solutions allow to calculate the mobility and diffusion coefficients as function of the electric field. The integral-differential equ

S. F. Liotta, A. Majorana

A set of equations is derived from the Boltzmann kinetic equation describing charge transport in semiconductors. The unknowns of these equations depend on the space-time coordinates and the electron energy. The non-parabolic and parabolic band approximation are treated in detail. In these cases, the set of equations is equivalent to those obtained in the sph

Francois Leonard, J. Tersoff

At semiconductor-metal junctions, the Schottky barrier height is generally fixed by "Fermi-level pinning". We find that when a semiconducting carbon nanotube is end-contacted to a metal (the optinal geometry for nanodevices), the behavior is radically different. Even when the Fermi level is fully "pinned" at the interface, the turn-on voltage

G. Cristofano, G. Maiella, V. Marotta

We extend the construction of the effective conformal field theory for the Jain hierarchical fillings proposed in cond-mat/9912287 to the description of a quantum Hall fluid at non standard fillings nu=m/(pm+2). The chiral primary fields are found by using a procedure which induces twisted boundary conditions on the m scalar fields; they appear as composite

S. Streubel, F. Mrowka, M. Wurlitzer, P. Esquinazi

We have studied the influence of the patterning procedure on the critical current density of high-$T_c$ YBa$_2$Cu$_3$O$_{7-δ}$ thin rings using the nonlinear ac susceptibility method. At no applied dc magnetic field we have found that laser ablation degrades strongly the critical current density whereas ion beam etching has only a weak influence on it. From

O. Narikiyo

We have combined the dynamical mean field theories of the Mott transition and the spin glass in infinite dimensions and derived a metallic spin-glass state from a random spin-fermion model.

F. Di Tolla, A. Dal Corso, J. A. Torres, E. Tosatti

We have carried out first principles electronic structure and total energy calculations for a series of ultrathin aluminum nanowires, based on structures obtained by relaxing the model wires of Gulseren et al. The number of conducting channels is followed as the wires radius is increased. The results suggest that pentagonal wires should be detectable, as the

L. Acedo, S. B. Yuste

The average number $S_N(t)$ of distinct sites visited up to time t by N noninteracting random walkers all starting from the same origin in a disordered fractal is considered. This quantity $S_N(t)$ is the result of a double average: an average over random walks on a given lattice followed by an average over different realizations of the lattice. We show for

L. Acedo, S. B. Yuste

We address the problem of evaluating the number $S_N(t)$ of distinct sites visited up to time t by N noninteracting random walkers all initially placed on one site of a deterministic fractal lattice. For a wide class of fractals, of which the Sierpinski gasket is a typical example, we propose that, after the short-time compact regime and for large N, $S_N(t)

V. G. Rostiashvili, T. A. Vilgis

By making use of the Langevin dynamics and its generating functional (GF) formulation the influence of the long-range nature of the interaction on the tendency of the glass formation is systematically investigated. In doing so two types of models is considered: (i) the non-disordered model with a pure repulsive type of interaction and (ii) the model with a r

Hiroyuki Tomita

The explicit form of the interface equation of motion derived assuming a minimal surface is extended to general bicontinuous interfaces that appear in the diffusion limited stage of the phase separation process of binary mixtures. The derivation is based on a formal solution of the equivalent simple layer for the Dirichlet problem of the Laplace equation wit

Iwan Jensen

We use the finite lattice method to calculate the radius of gyration, the first and second area-weighted moments of self-avoiding polygons on the square lattice. The series have been calculated for polygons up to perimeter 82. Analysis of the series yields high accuracy estimates confirming theoretical predictions for the value of the size exponent, $ν=3/4$,

Anthony J Guttmann, Iwan Jensen, Ling Heng Wong, Ian G Enting

We use the finite lattice method to count the number of punctured staircase and self-avoiding polygons with up to three holes on the square lattice. New or radically extended series have been derived for both the perimeter and area generating functions. We show that the critical point is unchanged by a finite number of punctures, and that the critical expone

Bambi Hu, De-gang Zhang, Bo-zang Li

We have studied quantum tunneling of large spins in a biaxial spin system and in a single-axial spin system with a transverse magnetic field. The asymptotically exact eigenvalues and eigenstates of the spin systems are obtained by solving the Mathieu equation. When the height $4q$ of energy barrier formed by the anisotropy and the magnetic field exceeds some

Le-Man Kuang, Zhao-Yang Tong, Zhong-Wen Ouyang, Hao-Sheng Zeng

In this paper, decoherence in a system consisting of two Bose-Einstein condensates is investigated analytically. It is indicated that decoherence can be controlled through manipulating the interaction between the system and environment. The influence of the decoherence on quantum coherent atomic tunneling (AT) between two condensates with arbitrary initial s

Steven S. Plotkin, Jose N. Onuchic

We use a free energy functional theory to elucidate general properties of heterogeneously ordering, fast folding proteins, and we test our conclusions with lattice simulations. We find that both structural and energetic heterogeneity can lower the free energy barrier to folding. Correlating stronger contact energies with entropically likely contacts of a giv

Akihisa Koga, Kouichi Okunishi, Norio Kawakami

We investigate the low-energy properties of the orthogonal-dimer spin chain characterized by a frustrated dimer-plaquette structure. When the competing antiferromagnetic couplings are varied, the first-order quantum phase transition occurs between the dimer and the plaquette phases, which is accompanied by nontrivial features due to frustration: besides the

Akihisa Koga, Norio Kawakami

We investigate the quantum phase transitions in the frustrated antiferromagnetic Heisenberg model for $\rm SrCu_2(BO_3)_2$ by using the series expansion method. It is found that a novel spin-gap phase, which is adiabatically connected to the plaquette-singlet phase, exists between the dimer and the magnetically ordered phases known so far. When the ratio of

Z. Dogic, S. Fraden

We report measurements of the cholesteric pitch and twist elastic constant $(K_{22})$ in monodisperse suspensions of the rod-like virus filamentous bacteriophage {\it fd}. Measurements were taken for concentrations spanning the entire cholesteric region at several ionic strengths and temperatures. In the limit of high ionic strength the cholesteric pitch $(P

Manojit Roy, V. Ravi Kumar, B. D. Kulkarni, John Sanderson

Submission withdrawn because the authors erroneously submitted a revised version as a new submission, see nlin.CD/0002028.

Sebastian Lopez, Hans-Juergen Hagen, Dieter Reimers

(Abridged) We report on HST FOS observations of the double QSO HS 1216+5032 AB (z(A)=1.455; z(B)=1.451, and angular separation theta=9 arcsec). An unusual broad-absorption-line (BAL) system is observed only in the B component: maximum outflow velocity of ~5000 km/s; probably a mixture of broad and narrow components. Observed ions are: HI, CII, CIII, NIII, NV

H. Yong, P. Demarque, S. Yi

The presence of a substantial number of hot stars in the extremely metal-rich} open cluster NGC6791 has been a mystery. If these hot stars are in their core helium burning phase, they are significantly bluer (hotter) than predicted by canonical stellar evolution theory. No obvious explanation is available yet. We consider the effects of mass loss during the

Daniel J. Rolfe, Carole A. Haswell, Joseph Patterson

The eclipsing novalike cataclysmic variable star V348 Pup exhibits a persistent luminosity modulation with a period 6 per cent longer than its 2.44 hour orbital-period (Porb). This has been interpreted as a `positive superhump' resulting from a slowly precessing non-axisymmetric accretion disc gravitationally interacting with the secondary. We find a cle

Andrew Gould, Amelia Stutz, Jay A. Frogel

We measure the ratio of total to selective extinction, R_{VI}=A_V/E(V-I), toward Baade's Window by comparing the VIK colors of 132 Baade's Window G and K giants from Tiede, Frogel, & Terndrup with the solar-neighborhood (V-I),(V-K) relation from Bessell & Brett. We find R_{VI}=2.283 +/- 0.016, and show that our measurement has no significant dependen

H Tadros, S J Warren, P C Hewett

We report preliminary results from a first season of photometric monitoring of 600 quasars behind the Virgo galaxy cluster with the aim of detecting microlensing by the cluster dark matter. Our project is sensitive to dark objects of surface mass densities down to ~20 g/cm^2. We are thus capable of detecting diffuse objects, such as cold molecular clouds, un

I. Ferreras, J. Silk

A simple model of chemical enrichment in cluster early-type galaxies is presented where the main parameters driving the formation of the stellar component are reduced to four: infall timescale (tf), formation epoch (zF), star formation efficiency (Ceff) and fraction of gas ejected in outflows (Bout). We find that only variations in Bout or Ceff can account f

A. Kurpiewski, M. Jaroszynski

We study the formation of the spectra in advection dominated accretion flows (ADAFs) around Kerr black holes. We use a Monte Carlo approach and fully general relativistic treatment to follow the paths of individual photons and model their scattering with mildly relativistic, thermal electrons of the two temperature plasma present in the flow. We study the in

Uta Fritze-v. Alvensleben

Observations of Young Star Cluster ({\bf YSC}) systems in interacting galaxies are reviewed with particular emphasis on their Luminosity Functions ({\bf LF}) and colour distributions. A few spectroscopic abundance measurements are available. They will be compared to YSC abundance predictions from spiral galaxy models. Evolutionary synthesis models allow to d

U. Fritze-v. Alvensleben

I discuss the chemical and spectrophotometric evolution of galaxies over cosmological timescales and present a first attempt to treat both aspects in a chemically consistent way. In our evolutionary synthesis approach, we account for the increasing metallicity of successive generations of stars and use sets of stellar evolutionary tracks, stellar yields, spe

Ann A. Esin, Roger Blandford

The deviation from the power-law decline of the optical flux observed in GRB 970228 and GRB 980326 has been used recently to argue in favor of the connection between GRBs and supernovae. We consider an alternative explanation for this phenomenon, based on the scattering of a prompt optical burst by 0.1 solar masses of dust located beyond its sublimation radi

David H. Hughes

One of the major goals of observational cosmology is to acquire empirical data that has the diagnostic power to develop the theoretical modelling of the high-redshift universe, ultimately leading to an accurate understanding of the processes by which galaxies and clusters form and subsequently evolve. New bolometer arrays operating on the world's largest

K. Torii, E. V. Gotthelf, G. Vasisht, T. Dotani

We present new results on the recently discovered 69 ms X-ray pulsar AXS J161730-505505, the sixth youngest sample of all known pulsars. We have undertaken a comprehensive X-ray observing campaign of AXS J161730-505505 with the ASCA, SAX, and XTE observatories and follow its long term spin-down history between 1989 and 1999, using these, archival GINGA and A

P. Cinzano, F. Falchi, C. D. Elvidge, K. E. Baugh

We present a method to map the artificial sky brightness across large territories in astronomical photometric bands with a resolution of approximately 1 km. This is useful to quantify the situation of night sky pollution, to recognize potential astronomical sites and to allow future monitoring of trends. The artificial sky brightness present in the chosen di

S. Piraino, A. Santangelo, A. Segreto, S. Giarrusso

We present the results from both the timing and spectroscopic analysis of the transient X-ray pulsar GS 1843+00 observed by the BeppoSAX satellite on 1997 April 4, when the source was at a luminosity of ~10^{37} erg s^{-1}. GS 1843+00 shows a very hard spectrum that is well fitted by an absorbed power law (N_H \~2.3 10^{22} cm^{-2}) modified by a high energy

Jens Hjorth, Stephen Holland, Frederic Courbin, Arnon Dar

We present deep HST imaging, as well as ground-based imaging and spectroscopy, of the optical afterglow associated with the long-duration gamma-ray burst GRB 990712 and its host galaxy. The data were obtained 48--123 days after the burst occurred. The magnitudes of the host (R = 21.9, V = 22.5) and optical afterglow (R = 25.4, V = 25.8, 47.7 days after the b

Sultana N. Nahar, Anil K. Pradhan, Hong Lin Zhang

The first complete set of unified cross sections and rate coefficients are calculated for photoionization and recombination of He- and Li-like ions using the relativistic Breit-Pauli R-matrix method. We present total, unified (e + ion) recombination rate coefficients for (e + C VI ---> C V) and (e + C V \longrightarrow C IV) including fine structure. Level-s

M. J. Duff, James T. Liu

We revive an old result, that one-loop corrections to the graviton propagator induce 1/r^3 corrections to the Newtonian gravitational potential, and compute the coefficient due to closed loops of the U(N) {\cal N}=4 super-Yang-Mills theory that arises in Maldacena's AdS/CFT correspondence. We find exact agreement with the coefficient appearing in the Ran

Konrad Banaszek

I derive a tight bound between the quality of estimating the state of a single copy of a $d$-level system, and the degree the initial state has to be altered in course of this procedure. This result provides a complete analytical description of the quantum mechanical trade-off between the information gain and the quantum state disturbance expressed in terms

Gregory F. Lawler, Oded Schramm, Wendelin Werner

We derive the exact value of intersection exponents between planar Brownian motions or random walks, confirming predictions from theoretical physics by Duplantier and Kwon. Let B and B' be independent Brownian motions (or simple random walks) in the plane, started from distinct points. We prove that the probability that the paths B[0,t] and B'[0,t] d

Bob Bacus, V. G. J. Rodgers

We numerically examine the self-dual solutions of self-intersecting strings immersed in four dimensions. We find that open torus knots have topologies that can support monopole/anti-monopole as well as q-qbar production and annihilation. We give an estimate of the string tension from quark production rates, show that the intersection number for torus-knots i

M. S. Hussein

We derive a generalized Low equation for the T-matrix appropriate for complex atom-molecule interaction. The properties of this new equation at very low energies are studied and the complex scattering length and effective range are derived.

R. Bellwied, H. Caines, T. J. Humanic

We investigate chemical and thermal freeze-out time dependencies for strange particle production for CERN SPS heavy ion collisions in the framework of a dynamical hadronic transport code. We show that the Lambda yield changes considerably after hadronization in the case of Pb+Pb collisions, whereas for smaller system sizes (e.g. S+S) the direct particle prod

Anand Dessai

We give bordism-finiteness results for manifolds with semi-simple group action. Consider the class of oriented manifolds which admit a circle action with isolated fixed points such that the action extends to an $S^3$-action with fixed point. We exhibit various subclasses, characterized by an upper bound for the Euler characteristic and properties of the firs

U. Leonhardt, G. E. Volovik

We suggest a procedure how to prepare the vortex with N=1/2 winding number -- the counterpart of the Alice string -- in a Bose--Einstein condensate with hyperfine spin F=1. Other possible vortices in Bose-condensates are also discussed.

N. Alonso-Alberca, P. Meessen, T. Ortin

We present warped metrics which solve Einstein equations with arbitrary cosmological constants in both in upper and lower dimensions. When the lower-dimensional metric is the maximally symmetric one compatible with the chosen value of the cosmological constant, the upper-dimensional metric is also the maximally symmetric one and there is maximal unbroken sup

Aric Hagberg, Ehud Meron, Thierry Passot

The slow dynamics of nearly stationary patterns in a FitzHugh-Nagumo model are studied using a phase dynamics approach. A Cross-Newell phase equation describing slow and weak modulations of periodic stationary solutions is derived. The derivation applies to the bistable, excitable, and the Turing unstable regimes. In the bistable case stability thresholds ar

Somshubhro Bandyopadhyay

Recently Badziag \emph{et al.} \cite{badziag} obtained a class of noisy states whose teleportation fidelity can be enhanced by subjecting one of the qubits to dissipative interaction with the environment via amplitude damping channel (ADC). We show that such noisy states result while sharing the states (| Φ^{\pm}> =\frac{1}{\sqrt{2}}(| 00> \pm | 11>)) across

Sergei V. Ketov

The N=2 superconformal Ward identities and their anomalies are discussed in N=2 superspace (including N=2 harmonic superspace), at the level of the low-energy effective action (LEEA) in four-dimensional N=2 supersymmetric field theories. The (first) chiral N=2 supergravity compensator is related to the known N=2 anomalous Ward identity in the N=2 (abelian) v

E. S. Sadki, Z. H. Barber, S. J. Lloyd, M. G. Blamire

We have studied the temperature dependence of the in-plane resistivity of NbN/AlN multilayer samples with varying insulating layer thickness in magnetic fields up to 7 Tesla parallel and perpendicular to the films. The upper critical field shows a crossover from 2D to 3D behavior in parallel fields. The irreversibility lines have the form (1-T/Tc)^alpha, whe

B. Basu-Mallick, Anjan Kundu

An integrable extension of the Calogero model is proposed to study the competing effect of momentum dependent long-range interaction over the original ${1 \ov r^2}$ interaction. The eigenvalue problem is exactly solved and the consequences on the generalized exclusion statistics, which appears to differ from the exchange statistics, are analyzed. Family of d

Jungyeon Cho, Ethan T. Vishniac

We have tested the ability of driven turbulence to generate magnetic field structure from a weak uniform field using three dimensional numerical simulations of incompressible turbulence. We used a pseudo-spectral code with a numerical resolution of up to $144^3$ collocation points. We find that the magnetic fields are amplified through field line stretching

Jungyeon Cho, Ethan T. Vishniac

We perform direct 3-dimensional numerical simulations for magnetohydrodynamic (MHD) turbulence in a periodic box of size $2π$ threaded by strong uniform magnetic fields. We use a pseudo-spectral code with hyperviscosity and hyperdiffusivity to solve the incompressible MHD equations. We analyze the structure of the eddies as a function of scale. A straightfor

Hans-Juergen Borchers, Detlev Buchholz, Bert Schroer

Polarization-free generators, i.e. ``interacting'' Heisenberg operators which are localized in wedge-shaped regions of Minkowski space and generate single particle states from the vacuum, are a novel tool in the analysis and synthesis of two-dimensional integrable quantum field theories. In the present article, the status of these generators is analy

Yuh Tomio, Yoshikazu Suzumura

Spin density wave (SDW) states at quarter-filling, which coexist with charge density wave (CDW) states, have been examined where the critical temperature is calculated for an extended Hubbard model with long range repulsive interactions. Within the mean-field theory, it is shown that the first order transition occurs with decreasing temperature for interacti

E. Kolbe, K. Langanke

We have calculated cross sections and branching ratios for neutrino induced reactions on ^{208}Pb and ^{56}Fe for various supernova and accelerator-relevant neutrino spectra. This was motivated by the facts that lead and iron will be used on one hand as target materials in future neutrino detectors, on the other hand have been and are still used as shielding

Friedrich Wagemann

The author regrets that after discussion of the results with B. L. Feigin a serious error has shown up. The proof of the results we presented in the paper is wrong. We thank B. L. Feigin for the discussion.

Friedrich Wagemann

We give explicit formulae for the generators of H^2(Hol(Σ_r,{\cal F}_λ(Σ_r)) in terms of affine and projective connections. This is done using the cocycles of V. Ovsienko and C. Roger for the case of the circle and globalizing them to an open Riemann surface Σ_r.

Friedrich Wagemann

We find crossed modules, i.e. certain 4 term exact sequences, associated to the Godbillon-Vey class for W_1, Vect(S^1), Vect_{1,0}(Σ) and Hol(Σ_r), i.e. for the Lie algebras of formal vector fields in 1 variable, vector fields on the circle, differentiable vector fields of holomorphic type on a Riemann surface and holomorphic vector fields on an open Riemann

A. Stoimenow

We give constructions to realize an odd number, which is representable as sum of two squares, as determinant of an achiral knot, thus proving that these are exactly the numbers occurring as such determinants. Later we study which numbers occur as determinants of prime alternating achiral knots, and obtain a complete result for perfect squares. Using the chec

Paul Hoyer, Martin Maul, Andreas Metz

We study the feasibility of measuring semi-exclusive photon production γ+ p \to γ+ Y at HERA. The cross section of photons produced at large transverse momenta, recoiling off an inclusive system Y of limited mass, can without photon isolation cuts be simply expressed in terms of hard pQCD subprocesses and standard target parton distributions. With the help o

George Efstathiou, Joop Schaye, Tom Theuns

The last few years have seen a dramatic improvement in our understanding of the origin of Lyman alpha absorption systems. Hydrodynamic numerical simulations of cold dark matter dominated universes have shown that the many properties of the Lyman alpha absorption systems can be explained by a photoionized, space-filling, intergalactic medium. Lyman alpha line

A. van Hameren, R. Kleiss

We describe a uniformly fast algorithm for generating points \vec{x} uniformly in a hypercube with the restriction that the difference between each pair of coordinates is bounded. We discuss the quality of the algorithm in the sense of its usage of pseudo-random source numbers, and present an interesting result on the correlation between the coordinates.

Gabor Etesi, Tamas Hausel

In this note we address the problem of finding Abelian instantons of finite energy on the Euclidean Schwarzschild manifold. This amounts to construct self-dual L^2 harmonic 2-forms on the space. Gibbons found a non-topological L^2 harmonic form in the Taub-NUT metric, leading to Abelian instantons with continuous energy. We imitate his construction in the ca

Sanefumi Moriyama

We solve the non-linear monopole equation of the Born-Infeld theory to all orders in the NS 2-form and give physical implications of the result. The solution is constructed by extending the earlier idea of rotating the brane configuration of the Dirac monopole in the target space. After establishing the non-linear monopole, we explore the non-commutative mon

Helmut Haberzettl

A comprehensive formalism is developed to preserve the gauge invariance of currents describing the photo- or electroproduction of mesons off the nucleon when the final-state interactions of mesons and nucleons is taken into account explicitly. Replacing exchange currents by auxiliary currents, it is found that all contributions due to explicit final-state in

R. M. Cavalcanti

We present a simple recipe to construct the Green's function associated with a Hamiltonian of the form H=H_0+V, where H_0 is a Hamiltonian for which the associated Green's function is known and V is a delta-function potential. We apply this result to the case in which H_0 is the Hamiltonian of a free particle in D dimensions. Field theoretic concepts

D. F. V. James

We present a brief critical review of the proposals for quantum computation with trapped ions, with particular emphasis on the possibilities for quantum computation without the need for cooling to the quantum ground state of the ions' collective oscillatory modes.

T. H. Hansson, S. B. Isakov, J. M. Leinaas, U. Lindstrom

Starting from the quantum theory of identical particles, we show how to define a classical mechanics that retains information about the quantum statistics. We consider two examples of relevance for the quantum Hall effect: identical particles in the lowest Landau level, and vortices in the Chern-Simons Ginzburg-Landau model. In both cases the resulting {\em

Michele Mosca, Alain Tapp, Ronald de Wolf

We investigate how a classical private key can be used by two players, connected by an insecure one-way quantum channel, to perform private communication of quantum information. In particular we show that in order to transmit n qubits privately, 2n bits of shared private key are necessary and sufficient. This result may be viewed as the quantum analogue of t

Ludvig Faddeev, Antti J. Niemi

We develop an effective field theory approach to inspect the electromagnetic interactions in an electrically neutral plasma, with an equal number of negative and positive charge carriers. We argue that the static equilibrium configurations within the plasma are topologically stable solitons, that describe knotted and linked fluxtubes of helical magnetic fiel

V. Mikhailovskii, A. I. Fisenko

The clean-up of several Creeks and Rivers by induction of a self-purification process was provided. The process took place at all the sites studied with the up to 100% resulted removal of polluting agents depending on the site and nature of the contaminant. The self-purification mechanism could be used for drinking and technical water preparation.

Luis Gonzalez-Mestres

An updated discussion of Lorentz symmetry violation in particle physics at very high energy is presented, focusing on applications of models of deformed Lorentz symmetry to high-energy astrophysics.

F. Bouchet, J. Sommeria

We explain the emergence and robustness of intense jets in highly turbulent planetary atmospheres, like on Jupiter, by a general approach of statistical mechanics of potential vorticity patches. The idea is that potential vorticity mixing leads to the formation of a steady organized coarse grained flow, corresponding to the statistical equilibrium state. Our

N. Itagaki, S. Okabe, K. Ikeda

The structure of the second 0^+ state of ^{10}Be is investigated using a microscopic $α+α+n+n$ model based on the molecular-orbit (MO) model. The second 0^+ state, which has dominantly the (1/2^+)^2 configuration, is shown to have a particularly enlarged $α-α$ structure. The kinetic energy of the two valence neutrons occupying along the $α-α$ axis is reduced

Gregor Veble, Ulrich Kuhl, Marko Robnik, Hans-Juergen Stoeckmann

In this work we study the eigenstates and the energy spectra of a generic billiard system with the use of microwave resonators. This is possible due to the exact correspondence between the Schroedinger equation and the electric field equations of the lowest modes in thin microwave resonators. We obtain a good agreement between the numerical (exact) and exper

Gregor Veble, Marko Robnik, Junxian Liu

In this work we semiclassically analyzed the high lying eigenstates of a mixed type Hamiltonian system. For the regular states we employ the Einstein-Brillouin-Keller quantization, while for the chaotic states, following the principle of uniform semiclassical condensation, we obtain a prediction for their wavefunction autocorrelation function.

Elliott H. Lieb

This is a brief review of the Thomas-Fermi ("statistical" or "density functional") theory of atoms and molecules.

Elliott H. Lieb

This is a brief review of Lieb-Thirring inequalities for eigenvalues of the Schroedinger operator and lower bounds for the quantum mechanical kinetic energy (and some generalizations) in R^n.

V. D. Gladush, A. V. Shcherbakov

The theory of recurrence relations of linear multi-component and multi-parameter systems on the basis of the canonical transformations theory of the dynamical systems' sets is constructed. The parameters of the grating's knots are defined from the condition of the invariance of the model under shifts along the grating. The connection with a zero curv

Holger Schanz, Uzy Smilansky

We present a few combinatorial identities which were encountered in our work on the spectral theory of quantum graphs. They establish a new connection between the theory of random matrix ensembles and combinatorics.

Ilya Zakharevich

We show that manifolds which parameterize values of first integrals of integrable finite-dimensional bihamiltonian systems carry a geometric structure which we call a {\em Kronecker web}. We describe two functors between Kronecker webs and integrable bihamiltonian structures, one is left inverse to another one. Conjecturally, these two functors are mutually

William Fulton

We describe recent work of Klyachko, Totaro, Knutson, and Tao, that characterizes eigenvalues of sums of Hermitian matrices, and decomposition of tensor products of representations of $GL_n(\mathbb{C})$. We explain related applications to invariant factors of products of matrices, intersections in Grassmann varieties, and singular values of sums and products

Israel M. Gelfand, Ilya Zakharevich

We introduce a criterion that a given bihamiltonian structure allows a local coordinate system where both brackets have constant coefficients. This criterion is applied to the bihamiltonian open Toda lattice in a generic point, which is shown to be locally isomorphic to a Kronecker odd-dimensional pair of brackets with constant coefficients. This shows that

Reinie Erne

In an earlier paper we showed that we can improve results by Emmy Noether and Alexander Ostrowski concerning the reducibility modulo p of absolutely irreducible polynomials with integer coefficients by giving the problem a geometric turn and using an arithmetic Bezout theorem. This paper is a generalization, where we show that combining the methods of that p

Elliot Benjamin, Franz Lemmermeyer, Chip Snyder

We classify all complex quadratic number fields with 2-class group of type (2,2^m) whose Hilbert 2-class fields have class groups of 2-rank equal to 2. These fields all have 2-class field tower of length 2. We still don't know examples of fields with 2-class field tower of length 3, but the smallest candidate is the field with discriminant -1015.

Peter Constantin

An Eulerian-Lagrangian approach to incompressible fluids that is convenient for both analysis and physics is presented. Bounds on burning rates in combustion and heat transfer in convection are discussed, as well as results concerning spectra.

Hugh L. Montgomery, K. Soundararajan

The authors study the distribution of psi(x+h)-psi(x)-h and compare it with numerical data.

F. Andreev, D. Auckly, L. Kapitanski, A. Kelkar

This note describes a method for generating an infinite-dimensional family of nonlinear control laws for underactuated systems. For a ball and beam system, the entire family is found explicitly.

V. V. Andrievskii, I. E. Pritsker, R. S. Varga

We establish a discrepancy theorem for signed measures, with a given positive part, which are supported on an arbitrary convex curve. As a main application, we obtain a result concerning the distribution of zeros of polynomials orthogonal on a convex domain.

U. Bunke

We verify that the formula of X. Ma for the analytic torsion form of an iterated fibration implies that Lott's secondary analytic index is functorial.

B. Kim, R. Pandharipande

We prove the connectedness of the moduli space of maps (of fixed genus and homology class) to the homogeneous space G/P by degeneration via the maximal torus action. In the genus 0 case, the irreducibility of the moduli of maps is a direct consequence of connectedness. An analysis of a related Bialynicki-Birula stratification of the map space yields a ration

Amanda W. Peet

We discuss spacetime singularity resolution in the context of the gravity/gauge correspondence, for brane systems which give rise to gauge theories with eight supercharges and no hypermultiplets. The discussion is aimed at non-experts. Writeup of talk on hep-th/9911161 with C.V.Johnson and J.Polchinski, given in various forms at: PASCOS-99, Aspen winter conf

J. R. Hiller, O. Lunin, S. Pinsky, U. Trittmann

We consider the Maldacena conjecture applied to the near horizon geometry of a D1-brane in the supergravity approximation and present numerical results of a test of the conjecture against the boundary field theory calculation using DLCQ. We previously calculated the two-point function of the stress-energy tensor on the supergravity side; the methods of Gubse

L. O'Raifeartaigh, J. M. Pawlowski, V. V. Sreedhar

It is shown that in the two-exponential version of Liouville theory the coefficients of the three-point functions of vertex operators can be determined uniquely using the translational invariance of the path integral measure and the self-consistency of the two-point functions. The result agrees with that obtained using conformal bootstrap methods. Reflection

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

We Study instanton solutions in general relativity with a scalar field. The metric ansatz we use is composed of a particular warp product of general Einstein metrics, such as those found in a number of cosmological settings, including string cosmology, supergravity compactifications and general Kaluza Klein reductions. Using the Hartle-Hawking prescription t

Masako Asano

We study the properties of branes in supergravity theory. We investigate a class of systems consisting of an M5-brane in the Kaluza-Klein monopole background with 1/4 supersymmetry in 11-dimensions. In the near core region of the KK-monopoles, the exact supergravity solution corresponding to each of these configurations is obtained. Then we argue the compact

Alexander I. Nesterov, Lev. V. Sabinin

A new mathematical theory, non-associative geometry, providing a unified algebraic description of continuous and discrete spacetime, is introduced.