January 2001 arXiv papers — page 10

Heng Fan, Keiji Matsumoto, Xiang-Bin Wang, Miki Wadati

Quantum cloning machines for equatorial qubits are studied. For the case of 1 to 2 phase-covariant quantum cloning machine, we present the networks consisting of quantum gates to realize the quantum cloning transformations. The copied equatorial qubits are shown to be separable by using Peres-Horodecki criterion. The optimal 1 to M phase-covariant quantum cl

Marcus Hutter

The Bayesian framework is ideally suited for induction problems. The probability of observing $x_t$ at time $t$, given past observations $x_1...x_{t-1}$ can be computed with Bayes' rule if the true distribution $μ$ of the sequences $x_1x_2x_3...$ is known. The problem, however, is that in many cases one does not even have a reasonable estimate of the tru

S. V. Chekanov

It was shown that at typical energies and luminosities of an $e^+e^-$ linear collider one can observe a significant suppression of fluctuations of the number of gluons in small angular regions. This property of jets is expected in $e^+e^-$ annihilation as well as in any collision producing high energy quarks which give rise to the QCD gluon cascade. The redu

M. Fujita, K. Yamada, H. Hiraka, P. M. Gehring

An elastic neutron scattering study has been performed on several single crystals of La$_{2-x}$Sr$_{x}$CuO$_{4}$ for {\it x} near the lower critical concentration {\it x$_{c}$} for superconductivity. % In the insulating spin-glass phase ({\it x} = 0.04 and 0.053), the previously reported one-dimensional spin modulation along the orthorhombic {\it b}-axis is

L. Silberman, A. Dekel, A. Eldar, I. Zehavi

We allow for nonlinear effects in the likelihood analysis of galaxy peculiar velocities, and obtain ~35%-lower values for the cosmological density parameter Om and the amplitude of mass-density fluctuations. The power spectrum in the linear regime is assumed to be a flat LCDM model (h=0.65, n=1, COBE) with only Om as a free parameter. Since the likelihood is

Brendan D. McKay, Norman D. Megill, Mladen Pavicic

We give a new algorithm for generating Greechie diagrams with arbitrary chosen number of atoms or blocks (with 2,3,4,... atoms) and provide a computer program for generating the diagrams. The results show that the previous algorithm does not produce every diagram and that it is at least 100,000 times slower. We also provide an algorithm and programs for chec

Norman D. Megill, Mladen Pavicic

We provide several new results on quantum state space, on lattice of subspaces of an infinite dimensional Hilbert space, and on infinite dimensional Hilbert space equations as well as on connections between them. In particular we obtain an n-variable generalized orthoarguesian equation which holds in any infinite dimensional Hilbert space. Then we strengthen

Wei Min Jin

In Minkowski flat space-time, it is perceived that time inversion is unitary rather than antiunitary, with energy being a time vector changing sign under time inversion. The Dirac equation, in the case of electromagnetic interaction, is not invariant under unitary time inversion, giving rise to a ``Klein paradox''. To render unitary time inversion in

Andrea Spiro

We determine an explicit expression for the Ricci tensor of a K-manifold, that is of a compact Kaehler manifold M with vanishing first Betti number, on which a semisimple group G of biholomorphic isometries acts with an orbit of codimension one. We also prove that the Kaehler form and the Ricci form of M are uniquely determined by two special curves with val

A. S. Belyaev, E. E. Boos, A. N. Vologdin, M. N. Dubinin

CompHEP, as a partonic event generator, and PYTHIA, as a generator of final states of detectable objects, are interfaced. Thus, integrated tool is proposed for simulation of (almost) arbitrary collision processes at the level of detectable particles. Exact (multiparticle) matrix elements, convolution with structure functions, decays, partons hadronization an

Hisakazu Minakata

I have discussed in my talk several remaining issues in the standard three-flavor mixing scheme of neutrinos, in particilar, the sign of $Δm^2_{13}$ and the leptonic CP violating phase. In this report I focus on two topics: (1) supernova method for determining the former sign, and (2) illuminating how one can detect the signatures for both of them in long-ba

Anatoli Polkovnikov, Georgy Zegrya

Influence of electron-electron relaxation processes on Auger recombination rate in direct band semiconductors is investigated. Comparison between carrier-carrier and carrier-phonon relaxation processes is provided. It is shown that relaxation processes are essential if the free path length of carriers doesn't exceed a certain critical value, which expone

B. Abou, D. Bonn, J. Meunier

The aging dynamics of colloidal suspensions of Laponite, a synthetic clay, is investigated using dynamic light stattering (DLS) and viscometry after a quench into the glassy phase. DLS allows to follow the diffusion of Laponite particles and reveals that there are two modes of relaxation. The fast mode corresponds to a rapid diffusion of particles within &#3

K. V. McCloud, M. L. Kurnaz

The roughness exponent of surfaces obtained by dispersing silica spheres into a quasi-two-dimensional cell is examined. The cell consists of two glass plates separated by a gap, which is comparable in size to the diameter of the beads. Previous work has shown that the quasi-one-dimensional surfaces formed have two distinct roughness exponents in two well-def

E. Levine, Y. Kafri, D. Mukamel

The evolution of a two-dimensional driven lattice-gas model is studied on an L_x X L_y lattice. Scaling arguments and extensive numerical simulations are used to show that starting from random initial configuration the model evolves via two stages: (a) an early stage in which alternating stripes of particles and vacancies are formed along the direction y of

Yoel Rephaeli

Observations with the RXTE and SAX satellites have recently led to the measurement of a second component in the spectra of several clusters of galaxies which are known to have regions of extended radio emission. This new component is quite likely nonthermal emission resulting from Compton scattering of relativistic electrons by the cosmic microwave backgroun

D. Yu. Tsvetkov, S. I. Blinnikov, N. N. Pavlyuk

The data on the location of gamma-ray bursts (GRBs) relative to their host galaxies are used to derive the distribution of surface density of GRBs along the galaxy radius. It is shown that the gradient of GRB surface density changes abruptly near the half-light radius. In the central parts of galaxies the distribution of GRBs resembles closely the luminosity

V. G. Ledenev, M. Karlicky, Y. Yan, Q. Fu

Observations of the solar radio emission in the microwave frequency range show fine structures consisting of a number of the almost parallel narrow frequency bands. We interpret these bands as the cyclotron harmonics plasma emission. This emission is generated by the anisotropic electron beam, which excites longitudinal waves on the normal Doppler effect res

Premana Premadi, Hugo Martel, Richard Matzner, Toshifume Futamase

Using a multiple-lens plane algorithm, we study light propagation in inhomogeneous universes, for 43 different COBE-normalized Cold Dark Matter models, with various values of the density parameter Omega_0, cosmological constant lambda_0, Hubble constant H_0, and rms density fluctuation sigma_8. This is the largest cosmological parameter survey ever done in t

M. Rovinsky

Let k be an algebraically closed field of characteristic zero, F its algebraically closed extension, and G be the group of k-automorphisms of F endowed with a natural topology. One of the purposes of this paper is to show that any non-faithful continuous representation of G factors through a discrete quotient of G. Properties of representation of G arising f

V. P. Frolov, D. V. Fursaev

We find exact solutions of the Einstein equations which describe a black hole pierced by infinitely thin cosmic strings. The string segments enter the black hole along the radii and their positions coincide with the symmetry axes of a regular polyhedron. Each string produces an angle deficit proportional to its tension, while the metric outside the strings i

S. S. Wu, H. X. Zhang, Y. J. Yao

If baryons couple only with $ω$-mesons, one found the baryon spectral function may be negative. We show this unacceptable result is caused by the $k_μk_ν$-terms in the $ω$-meson propagator. Their contribution may not vanish in approximate calculations which violate the baryon current conserves. A rule is suggested, by which the calculated baryon spectral fun

Chang Ho Hyun, Tae-Sun Park, Dong-Pil Min

Heavy-baryon chiral perturbation theory (HBChPT) is applied to the asymmetry $A_γ$ in $\vec{n} + p \to d + γ$ at threshold, which arises due to the weak parity non-conserving interactions. Instead of appealing to Siegert's theorem, transition operators up to next-to-leading chiral order are derived and the corresponding amplitudes are evaluated with the

Brett McInnes

Using the generalised AdS/CFT correspondence, we show that there are certain ten-dimensional differentiable manifolds such that string theory on such a manifold is unstable [to the emission of "large branes"] no matter what the metric may be. The instability is thus due to the [differential] topology of the manifold, not to any particular choice of its geome

C. Lupien, W. A. MacFarlane, Cyril Proust, Louis Taillefer

We present a study of the electronic ultrasound attenuation $α$ in the unconventional superconductor Sr$_2$RuO$_4$ . The power law behavior of $α$ at temperatures down to $T_c/30$ clearly indicates the presence of nodes in the gap. In the normal state, we find an enormous anisotropy of $α$ in the basal plane of the tetragonal structure. In the superconductin

Frederik Denef, Brian Greene, Mark Raugas

We investigate the spectrum of type IIA BPS D-branes on the quintic from a four dimensional supergravity perspective and the associated split attractor flow picture. We obtain some very concrete properties of the (quantum corrected) spectrum, mainly based on an extensive numerical analysis, and to a lesser extent on exact results in the large radius approxim

Alfred Tang, Daniel R. Shillinglaw, George Nill

The non-relativistic Schrodinger equation with the linear and Coulomb potentials is solved numerically in configuration space using the relaxation method. The numerical method presented in this paper is a plain explicit Schrodinger solver which is conceptually simple and is suitable for advanced undergraduate research.

V. A. Khodel, J. W. Clark, M. V. Zverev

The phase transitions in a realistic system with triplet pairing, dense neutron matter, have been investigated. The spectrum of phases of the $^3P_2-^3F_2$ model, which adequately describes pairing in this system, is analytically constructed with the aid of a separation method for solving BCS gap equation in states of arbitrary angular momentum. In addition

Mikhail Kopytine

NA44 uses a 512 channel Si pad array covering $1.5 <η< 3.3$ to study charged hadron production in Pb+Pb collisions at the CERN SPS. We apply a multiresolution analysis, based on a Discrete Wavelet Transformation, to probe the texture of particle distributions event-by-event, by simultaneous localization of features in space and scale. Scanning a broad range

Henryk Fuks, Nino Boccara

We conjecture that for a wide class of interacting particle systems evolving in discrete time, namely conservative cellular automata with piecewise linear flow diagram, relaxation to the limit set follows the same power law at critical points. We further describe the structure of the limit sets of such systems as unions of shifts of finite type. Relaxation t

Marshall A. Whittlesey

Let S be a generic C-infinity smooth CR manifold in C^n, n > 1, and let M be a generic C-infinity CR submanifold of S X C^m. We prescribe conditions on M so that it is the disjoint union of graphs of CR maps f:S-->C^m. We also consider the special case where S is the boundary of a bounded, smoothly bounded open set D in C^n, n > 1. In this case we obtain con

Igor E. Pritsker

We study the problem of minimizing the supremum norm, on a segment of the real line or on a compact set in the plane, by polynomials with integer coefficients. The extremal polynomials are naturally called integer Chebyshev polynomials. Their factors, zero distribution and asymptotics are the main subjects of this paper. In particular, we show that the integ

Stoil Donev

This paper presents the transition from Classical Electrodynamics (CED) to Extended Electrodynamics (EED) from the electromagnetic duality point of view, and emphasizes the role of the canonical complex structure in ${\cal R}^2$ in, both, nonrelativistic and relativistic formulations of CED and EED. We begin with summarizing the motivations for passing to EE

Mariano Quiros

In this talk we review the actual situation concerning electroweak phase transition and baryogenesis in the minimal supersymmetric extension of the Standard Model. A strong enough phase transition requires light Higgs and stop eigenstates. For a Higgs mass in the range 110--115 GeV, there is a stop window in the range 105--165 GeV. If the Higgs is heavier th

Ilya F. Ginzburg, Maria Krawczyk, Per Osland

After operations at the LHC and e^+e^- Linear Colliders it may be found that a Standard-Model-like scenario is realized. In this scenario no new particle will be discovered, except a single Higgs boson having partial widths or coupling constants squared with fundamental particles close, within anticipated experimental uncertainty, to those of the SM. Experim

Kirill Melnikov

Radiative corrections to the Casimir force between two parallel plates are considered in both scalar field theory of one massless and one massive field and in QED. Full calculations are contrasted with calculations based on employing ``boundary-free&#39;&#39; effective field theories. The difference between two previous results on QED radiative corrections t

Christos Touramanis

The BABAR detector at the SLAC PEP-II asymmetric e+e- collider has first started collecting data in May 1999. A study of time-dependent CP-violating asymmetries in B0 --> J/psi K0S and B0 --> psi(2S) K0S decays has been performed on a data sample of 9.0fb-1 taken at the Y(4S) resonance and 0.8fb-1 off-resonance, collected through July 2000. The preliminary r

Timothy Gershon

The NA48 experiment at CERN has performed a measurement of direct CP violation in the neutral kaon system, based on data collected in 1997 and 1998. The preliminary result for the parameter $\Re(ε^{\prime}/ε)$ is $(14.0 \pm 4.3) \times 10^{-4}$.

V. Pravda, J. Bicak

It is well known that all curvature invariants of the order zero vanish for type-III and type-N vacuum spacetimes. We briefly summarize properties of higher order curvature invariants for these spacetimes.

A. Pravdova, J. Bicak

Main results concerning allowable additional symmetries of axially symmetric electrovacuum spacetimes are summarized. These are translational Killing vectors and the boost Killing vector. However, this is only the boost symmetry that does not exclude radiation and permit a spacetime to be asymptotically flat with global null infinity.

Richard P. Sear

Homogeneous nucleation of a new phase near a second, continuous, transition, is considered. The continuous transition is in the metastable region associated with the first-order phase transition, one of whose coexisting phases is nucleating. Mean-field calculations show that as the continuous transition is approached, the size of the nucleus varies as the re

Sanjeev Kumar, Pinaki Majumdar

Recent experiments on the amorphous magnetic semiconductor Gd_x Si_{1-x}, Phys. Rev. Lett. 77, 4652 (1996), ibid 83, 2266 (1999), ibid 84, 5411 (2000), ibid 85, 848 (2000), have revealed an insulator-metal transition (i-m-t), as a function of doping and magnetic field, a spin glass state at low temperature, and colossal magnetoresistance close to the i-m-t.

Pragya Shukla

We study the level-statistics of a disordered system undergoing the Anderson type metal-insulator transition. The disordered Hamiltonian is a sparse random matrix in the site representation and the statistics is obtained by taking an ensemble of such matrices. It is shown that the transition of levels due to change of various parameters e.g. disorder, system

I. Santamaría-Holek, D. Reguera, J. M. Rubí

We analyze the diffusion of a Brownian particle in a fluid under stationary flow. By using the scheme of non-equilibrium thermodynamics in phase space, we obtain the Fokker-Planck equation which is compared with others derived from kinetic theory and projector operator techniques. That equation exhibits violation of the fluctuation dissipation-theorem. By im

Tom Richtler, Ram Sagar

We present new CCD photometry of the distant old open star cluster Berkeley 32 in Johnson V and Cousins I passbands. A total of about 3200 stars have been observed in a field of 13X13 arcmin**2. The colour-magnitude diagram in V, (V-I) has been generated down to V = 22 mag. A broad but well defined main sequence is clearly visible. Some blue stragglers, a we

H. -Th. Janka, M. Ruffert

Merging neutron stars and neutron star-black holes binaries are powerful sources of gravitational waves. They have also been suggested as possible sources of cosmic gamma-ray bursts and are discussed as sites for the formation of r-process elements. Whereas the first aspect is undoubtable, the latter two are very uncertain. The current status of our knowledg

Henry C. Ferguson

Results from a recent HST survey of field galaxies at wavelengths 1600 Angstroms and 2400 Angstroms are be presented. The data are used to constrain the fraction of Lyman-continuum radiation that escapes from galaxies at redshifts z ~ 1. The combined UV-IR photometry for HDF galaxies is also used to investigate whether low-mass starburst galaxies dominate th

Jiancheng Wang

We present that the radio emission with flat spectrum in X-ray binaries comes from the synchrotron emission of relativistic electrons in the high energy tail of hot electrons in continuous conical jet. The jet is assumed to be produced by the advection-dominated accretion flow (ADAF) and maintains ion and electron temperatures constant in the case of adiabat

Tzu-Ching Chang, Jacqueline H. van Gorkom, Ann. I. Zabludoff, Dennis Zaritsky

We present the results of HI line and radio continuum observations of five nearby E+A galaxies. These galaxies have spectra that are dominated by a young stellar component but lack the emission lines characteristic of significant, on-going star formation. They are selected from a unique sample of 21 E+A&#39;s identified by Zabludoff et al.(1996) in their spe

Lev I. Deych, Alexey Yamilov, Alexander A. Lisyansky

We study analytically defect polariton states in Bragg multiple-quantum-well structures and defect induced changes in transmission and reflection spectra. Defect layers can differ from the host layers in three ways: exciton-light coupling strength, exciton resonance frequency, and inter-well spacing. We show that a single defect leads to two local polariton

F. D. R. Bonnet, P. O. Bowman, D. B. Leinweber, A. G. Williams

We extend a previous improved action study of the Landau gauge gluon propagator, by using a variety of lattices with spacings from $a = 0.17$ to 0.41 fm, to more fully explore finite volume and discretization effects. We also extend a previously used technique for minimizing lattice artifacts, the appropriate choice of momentum variable or ``kinematic correc

S. J. Burby, E. W. N. Glover

We present predictions of two event shape distributions, the light hemisphere mass and the narrow jet broadening, to next-to-leading logarithmic order. We apply the coherent branching formalism to resum the leading O(alphas^n L^{2n-1}) and next-to-leading O(alphas^n L^{2n-2}) infrared logarithms to all orders in the coupling constant. We include the recently

Sumati Surya, Kristin Schleich, Donald M. Witt

We reexamine the thermodynamics of adS black holes with Ricci flat horizons using the adS soliton as the thermal background. We find that there is a phase transition which is dependent not only on the temperature, but also on the black hole area, which is an independent parameter. As in the spherical adS black hole, this phase transition is related via the a

Roland R. Netz, David Andelman

This chapter deals with charged polymers (polyelectrolytes) in solution and at surfaces. The behavior of polyelectrolytes is markedly different from that of neutral polymers. In bulk solutions, i.e. disregarding the surface effect, there are two unique features to charged polymers: first, due to the presence of long-ranged electrostatic repulsion between cha

Matthias Kreck

In this note we classify the diffeomorphism classes rel. boundary of smooth h-cobordisms between two fixed 1-connected 4-manifolds in terms of isometries between the intersection forms.

Jiong-Ming Zhu, Bin Wang, Elcio Abdalla

We investigated the evolution of a scalar field propagating in small Schwarzschild Anti-de Sitter black holes. The imaginary part of the quasinormal frequency decreases with the horizon size and the real part of the quasinormal frequency keeps nearly as a constant. The object-picture clarified the question on the quasinormal modes for small Anti-de Sitter bl

J. G. Russo

We compute the one-loop contribution to the free energy in eleven-dimensional supergravity, with the eleventh dimension compactified on a circle of radius $R_{11}$. We find a finite result, which, in a small radius expansion, has the form of the type IIA supergravity free energy plus non-perturbative corrections in the string coupling $g_A$, whose coefficien

Finn Ravndal, Jan B. Thomassen

We discuss radiative corrections to the Casimir effect from an effective field theory point of view. It is an improvement and more complete version of a previous discussion by Kong and Ravndal. By writing down the most general effective Lagrangian respecting the symmetries and the boundary conditions, we are able to reproduce earlier results of Bordag, Robas

Nicolas Gisin, Grégoire Ribordy, Wolfgang Tittel, Hugo Zbinden

Quantum cryptography could well be the first application of quantum mechanics at the individual quanta level. The very fast progress in both theory and experiments over the recent years are reviewed, with emphasis on open questions and technological issues.

Jian Dai, Xing-Chang Song

Differential structure of a d-dimensional lattice, which is essentially a noncommutative exterior algebra, is defined using reductions in first order and second order of universal differential calculus in the context of noncommutative geometry (NCG) developed by Dimakis et al. This differential structure can be realized adopting a Dirac-Connes operator propo

D. V. Khveshchenko

Some unusual properties of layered graphite, including a linear energy dependence of the quasiparticle damping and weak ferromagnetism at low doping, are explained as a result of the proximity of a single graphene sheet to the excitonic insulator phase which can be further stabilized in a doped system of many layers stacked in the staggered ($ABAB...$) confi

Luiz A. Manzoni, Walter F. Wreszinski

We develop a mathematically precise framework for the Casimir effect. Our working hypothesis, verified in the case of parallel plates, is that only the regularization-independent Ramanujan sum of a given asymptotic series contributes to the Casimir pressure. As an illustration, we treat two cases: parallel plates, identifying a previous cutoff free version (

A. G. Magner, S. N. Fedotkin, K. Arita, K. Matsuyanagi

We have derived a semiclassical trace formula for the level density of the three-dimensional spheroidal cavity. To overcome the divergences occurring at bifurcations and in the spherical limit, the trace integrals over the action-angle variables were performed using an improved stationary phase method. The resulting semiclassical level density oscillations a

A. Niégawa

We aim to construct from first principles a perturbative framework for studying nonequilibrium quantum-field systems that include massless Dirac fermions. The system of our concern is quasiuniform system near equilibrium or nonequilibrium quasistationary system. We employ the closed-time-path formalism and use the so-called gradient approximation. Essentiall

Xiaoyuan Li, Yi Liao

We study the form factors of the low energy anomalous pion-2-photon and photon-3-pion processes in the nonlocal chiral quark model which incorporates the momentum dependence of the dynamical quark mass and realizes correctly the chiral symmetries. The obtained slope parameter for pion-2-photon is in reasonable agreement with the direct experimental results b

S. M. Kuzenko, I. N. McArthur

Using the N = 2 off-shell formulation in harmonic superspace for N = 4 super Yang-Mills theory, we present a representation of the one-loop effective action which is free of so-called coinciding harmonic singularities and admits a straightforward evaluation of low-energy quantum corrections in the framework of an N = 2 superfield heat kernel technique. We il

Chang-Ming Ho, V. N. Muthukumar, Masao Ogata, P. W. Anderson

We investigate the excitation spectrum of a two-dimensional resonating valence bond (RVB) state. Treating the $pi$-flux phase with antiferromagnetic correlations as a variational ground state, we recover the long wavelength magnon as an &#34;RVB exciton&#34;. However, we find that this excitation does NOT exhaust the entire spectral weight and the high energ

D. L. Block, I. Puerari, M. Takamiya, R. Abraham

Results from the Hubble Deep Field (HDF) North and South show a large percentage of high-redshift galaxies whose appearance falls outside traditional classification systems. The nature of these objects is poorly understood, but sub-mm observations indicate that at least some of these systems are heavily obscured (Sanders 2000). This raises the intriguing pos

D. J. Thouless, M. R. Geller, W. F. Vinen, J. -Y. Fortin

We have used two-fluid dynamics to study the discrepancy between the work of Thouless, Ao and Niu (TAN) and that of Iordanskii. In TAN no transverse force on a vortex due to normal fluid flow was found, whereas the earlier work found a transverse force proportional to normal fluid velocity u and normal fluid density. We have linearized the time-independent t

Washington Taylor

A self-contained review is given of the matrix model of M-theory. The introductory part of the review is intended to be accessible to the general reader. M-theory is an eleven-dimensional quantum theory of gravity which is believed to underlie all superstring theories. This is the only candidate at present for a theory of fundamental physics which reconciles

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

We consider non-universal cloning maps, namely cloning transformations which are covariant under a proper subgroup G of the universal unitary group U(d), where d is the dimension of the Hilbert space H of the system to be cloned. We give a general method for optimizing cloning for any cost-function. Examples of applications are given for the phase-covariant

J. J. Halliwell

The decoherent histories approach is a natural medium in which to address problems in quantum theory which involve time in a non-trivial way. This article reviews the various attempts and difficulties involved in using the decoherent histories approach to calculate the probability for crossing the surface $x=0$ during a finite interval of time. The commonly

Stefano Mancini, Alessandra Gatti

We study the phenomena that arise in the transverse structure of electromagnetic field impinging on a linear Fabry-Perot cavity with an oscillating end mirror. We find quantum correlations among transverse modes which can be considered as a signature of their entanglement.

Osamu Hirota, Steven J. van Enk, Kazuo Nakamura, Masaki Sohma

This paper presents properties of the so-called quasi-Bell states: entangled states written as superpositions of nonorthogonal states. It is shown that a special class of those states, namely entangled coherent states, are more robust against decoherence due to photon absorption than the standard bi-photon Bell states.

Deborah Kuchnir Fygenson

Microtubule dynamic instability arises from the hydrolysis of GTP bound to the beta-monomer of the tubulin dimer. The conformational change induced by hydrolysis is unknown, but microtubules disassemble into protofilaments of GDP-bound tubulin that curve away from the microtubule axis. This paper presents the unfolding of a portion of the tubulin molecule in

U. Lombardo, P. Schuck, W. Zuo

The superfluidity of neutron matter in the channel $^1 S_0$ is studied by taking into account the effect of the ground-state correlations in the self-energy. To this purpose the gap equation has been solved within the generalized Gorkov approach. A sizeable suppression of the energy gap is driven by the quasi-particle strength around the Fermi surface.

E. Garrido, D. V. Fedorov, A. S. Jensen

We describe a reaction mechanism which is consistent with all available experimental information of high energy three-body breakup processes. The dominating channels are removal of one of the three halo particles leaving the other two either undisturbed or absorbed. We compare with the commonly used deceptive assumption of a decay through two-body resonance

S. E. Massen, C. P. Panos

A direct connection of information entropy $S$ and kinetic energy $T$ is obtained for nuclei and atomic clusters, which establishes $T$ as a measure of the information in a distribution. It is conjectured that this is a universal property for fermionic many-body systems. We also check rigorous inequalities previously found to hold between S and T for atoms a

G. J. Lolos

The rho-0 has been photoproduced using tagged photon energies in the 700-1120 MeV region on 2H, 3He and 12C by utilizing the Fermi momentum of the bound nucleons to produce the rho-0. These energies lie mostly below the production threshold on the free proton. Large mass modifications are indicated from the analysis, together with large polarizations of the

Alessandro P. S. de Moura, Celso Grebogi

We present a novel method for the calculation of the fractal dimension of boundaries in dynamical systems, which is in many cases many orders of magnitude more efficient than the uncertainty method. We call it the Output Function Evaluation (OFE) method. The OFE method is based on an efficient scheme for computing output functions, such as the escape time, o

Maxim Pavlov

In this paper we present a two-component generalization of the C-integrable Calogero equation (see [1]). This system is C-integrable as well, and moreover we show that the Calogero equation and its two-component generalization are solvable by a reciprocal transformation to ODE&#39;s. Simultaneously we obtain a generalized Liouville equation (34), determined

Sami I. Muslih

The abelian Chern-Simons system is treated as a constrained system using the Hamilton-Jacobi approach. The equations of motion are obtained as total differential equations in many variables. It is shown that their simultaneous solutions with the constraints lead to obtain canonical phase space coordinates and the reduced phase space Hamiltonian with out intr

M. A. Akivis, V. V. Goldberg, J. M. Landsberg

We exhibit examples of projective varieties with degenerate Gauss mappings and determine numerical invariants of such varieties. Our examples provide counter-examples to an asserted structure theorem of Griffiths and Harris (Ann. Sci. ENS 1979).

Colin Rourke, Brian Sanderson

We use the compression theorem (arxiv:math.GT/9712235) cf section 7, to prove results for equivariant configuration spaces analogous to the well-known non-equivariant results of May, Milgram and Segal.

Igor E. Pritsker

We study inequalities connecting a product of uniform norms of polynomials with the norm of their product. Generalizing Gel&#39;fond-Mahler inequality for the unit disk and Kneser-Borwein inequality for the segment $[-1,1]$, we prove an asymptotically sharp inequality for norms of products of algebraic polynomials over an arbitrary compact set in plane. Appl

Charles Rezk, Stefan Schwede, Brooke Shipley

We produce a highly structured way of associating a simplicial category to a model category which improves on work of Dwyer and Kan and answers a question of Hovey. We show that model categories satisfying a certain axiom are Quillen equivalent to simplicial model categories. A simplicial model category provides higher order structure such as composable mapp

Bert van Geemen

Allcock and Freitag recently showed that the moduli space of marked cubic surfaces is a subvariety of a nine dimensional projective space which is defined by cubic equations. They used the theory of automorphic forms on ball quotients to obtain these results. Here we describe the same embedding using Naruki&#39;s toric model of the moduli space. We also give

D. Arnaudon, A. Chakrabarti, V. K. Dobrev, S. G. Mihov

In the classification of Hietarinta, three triangular $4\times 4$ $R$-matrices lead, via the FRT formalism, to matrix bialgebras which are not deformations of the trivial one. In this paper, we find the bialgebras which are in duality with these three exotic matrix bialgebras. We note that the $L-T$ duality of FRT is not sufficient for the construction of th

Jesus Araujo

It is proved that every linear biseparating map between spaces of vector-valued differentiable functions is a weighted composition map. As a consequence, such a map is always continuous.

Yoshinori Namikawa

The notion of a holomorphically symplectic manifold can be generalized to the singular one. This paper studies the birational contraction maps between symplectic varieties, and then describes the deformation of a symplectic variety which has a symplectic resolution. Some examples are also included.

Mihai Halic

The article investigates the following question: given a projective variety X acted on by a connected and reductive group G, which is the relationship between the Gromov-Witten invariants of X and those of X//G? In this study we shall also try to give an algebraic approach to the so called Hamiltonian Gromov-Witten invariants which have appeared rather recen

Bjorn Andreas, Gottfried Curio, Daniel Hernandez Ruiperez, Shing-Tung Yau

Fibrewise T-duality (Fourier-Mukai transform) for D-branes on an elliptic Calabi-Yau $X$ is shown to require naturally an appropriate twisting of the operation respectively a twisted charge. The fibrewise T-duality is furthermore expressed through known monodromies in the context of Kontsevich's interpretation of mirror symmetry.

A. V. Radyushkin

Applications of perturbative QCD to deeply virtual Compton scattering and hard exclusive electroproduction processes require a generalization of the usual parton distributions for the case when long-distance information is accumulated in nondiagonal matrix elements of quark and gluon light-cone operators. I describe two types of nonperturbative functions par

B. W. Filippone, Xiangdong Ji

We present an overview of recent experimental and theoretical advances in our understanding of the spin structure of protons and neutrons.

V. A. Bednyakov, H. V. Klapdor-Kleingrothaus, H. Tu

We investigated the contribution of the MSSM Higgs bosons produced in the neutralino annihilation in the Earth and Sun to the total WIMPs detection signals. We found that this contribution is very important and results in a lower bound for the muon flux from the Sun of 10^{-7} - 10^{-8} m^{-2} yr^{-1} for neutralinos heavier than 200 GeV. We noticed that due

B. Andersson, F. Soderberg, S. Mohanty

The assumptions in the Lund model suffice to prescribe a unique stochastic process for the fragmentation of a string into a set of hadrons, so long as the string is &#34;flat&#34;, ie as long as the state described by the string consists only of a quark and an antiquark stretching a constant force field between them. Emission of gluons causes the string to t

A Donnachie, J Gravelis, G Shaw

A two-component model is developed for diffractive electroproduction of $ρ^0$, $ϕ$ and $\jpsi$, based on non-perturbative and perturbative two-gluon exchange. This provides a common kinematical structure for non-perturbative and perturbative effects, and allows the role of the vector-meson vertex functions to be explored independently of the production dynam

J. O. Eeg, S. Fajfer, J. Zupan

We point out that the decay mode D^0 -> K^0 \bar{K^0} has no factorizable contribution. In the chiral perturbation language, treating D^0 as heavy, the O(p) contribution is zero. We calculate the nonfactorizable chiral loop contributions of order O(p^3). Then, we use a heavy-light type chiral quark model to calculate nonfactorizable tree level terms, also of

Stefano Bertolini

I shortly review the present status of the theoretical estimates of eps&#39;/eps. I consider a few aspects of the theoretical calculations which may be relevant in understanding the present experimental results. I discuss the role of higher order chiral corrections and in general of non-factorizable contributions for the explanation of the Delta I = 1/2 sele

D. B. Leinweber, A. W. Thomas, R. D. Young

Understanding hadron structure within the framework of QCD is an extremely challenging problem. In order to solve it, it is vital that our thinking should be guided by the best available insight. Our purpose here is to explain the model independent consequences of the approximate chiral symmetry of QCD for two famous results concerning the structure of the n