May 1999 arXiv papers — page 9

A. Halperin, Paul M. Goldbart

Interest in the protein folding problem has motivated a wide range of theoretical and experimental studies of the kinetics of the collapse of flexible homopolymers. In this Paper a phenomenological model is proposed for the kinetics of the early stages of homopolymer collapse following a quench from temperatures above to below the theta temperature. In the f

Parameswaran Gopikrishnan, Vasiliki Plerou, Luis A. Nunes Amaral, Martin Meyer

We study the distribution of fluctuations over a time scale $Δt$ (i.e., the returns) of the S&P 500 index by analyzing three distinct databases. Database (i) contains approximately 1 million records sampled at 1 min intervals for the 13-year period 1984-1996, database (ii) contains 8686 daily records for the 35-year period 1962-1996, and database (iii) conta

S. Paulson, M. R. Falvo, N. Snider, A. Helser

We investigate the response of multi-walled carbon nanotubes to mechanical strain applied with an Atomic Force Microscope (AFM) probe. We find that in some samples, changes in the contact resistance dominate the measured resistance change. In others, strain large enough to fracture the tube can be applied without a significant change in the contact resistanc

Azadeh Samadani, A. Pradhan, A. Kudrolli

We present an experimental study of segregation of granular matter in a quasi-two dimensional silo emptying out of an orifice. Size separation is observed when multi-sized particles are used with the larger particles found in the center of the silo in the region of fastest flow. We use imaging to study the flow inside the silo and quantitatively measure the

Gabriel Tellez, Thierry Biben

We investigate the sedimentation equilibrium of a charge stabilized colloidal suspension in the regime of low ionic strength. We analyze the asymptotic behaviour of the density profiles on the basis of a simple Poisson--Boltzmann theory and show that the effective mass we can deduce from the barometric law corresponds to the actual mass of the colloidal part

M. Conti, U. Marini Bettolo Marconi, A. Crisanti

We present a novel picture of a non isothermal solidification process starting from a molecular level, where the microscopic origin of the basic mechanisms and of the instabilities characterizing the approach to equilibrium is rendered more apparent than in existing approaches based on coarse grained free energy functionals à la Landau. The system is compose

Roger Bidaux, Jerome Chave, Radim Vocka

We evaluate the limit distribution of the maximal excursion of a random walk in any dimension for homogeneous environments and for self-similar supports under the assumption of spherical symmetry. This distribution is obtained in closed form and is an approximation of the exact distribution comparable to that obtained by real space renormalization methods. T

S. Redner, P. L. Krapivsky

We study the capture of a diffusing "lamb" by diffusing "lions" in one dimension. The capture dynamics is exactly soluble by probabilistic techniques when the number of lions is very small, and is tractable by extreme statistics considerations when the number of lions is very large. However, the exact solution for the general case of three or

U. Zuelicke, A. H. MacDonald, M. D. Johnson

We consider the edge of a two-dimensional electron system that is in the quantum-Hall-effect regime at filling factor 1-1/m with m being an odd integer, where microscopic theory explaining the occurrence of the quantum Hall effect in the bulk predicts the existence of two counterpropagating edge-excitation modes. These two modes are the classical edge-magnet

S. Waffenschmidt, C. Pfleiderer, H. v. Loehneysen

We report new measurements of the electrical conductivity sigma of the canonical three-dimensional metal-insulator system Si:P under uniaxial stress S. The zero-temperature extrapolation of sigma(S,T -> 0) ~§- S_cmu shows an unprecidentedly sharp onset of finite conductivity at S_c with an exponent mu = 1. The value of mu differs significantly from that of e

R. Combescot

We consider the effect of the indirect interaction due to the exchange of density fluctuations on the critical temperature of superfluid $^{6}$Li . We obtain the strong coupling equation giving this critical temperature. This equation is solved approximately by retaining the same set of diagrams as in the paramagnon model. We show that, near the instability

M. Krech, D. P. Landau

We present extensive Monte-Carlo spin dynamics simulations of the classical XY model in three dimensions on a simple cubic lattice with periodic boundary conditions. A recently developed efficient integration algorithm for the equations of motion is used, which allows a substantial improvement of statistics and large integration times. We find spin wave peak

H. Y. Lee, H. -W. Lee, D. Kim

We present an empirical phase diagram of the congested traffic flow measured on a highway section with one effective on-ramp. Through the analysis of local density-flow relations and global spatial structure of the congested region, four distinct congested traffic states are identified. These states appear at different levels of the upstream flux and the on-

Julyan H. E. Cartwright, Victor M. Eguiluz, Emilio Hernandez-Garcia, Oreste Piro

The Burridge-Knopoff model of earthquake faults with viscous friction is equivalent to a van der Pol-FitzHugh-Nagumo model for excitable media with elastic coupling. The lubricated creep-slip friction law we use in the Burridge-Knopoff model describes the frictional sliding dynamics of a range of real materials. Low-dimensional structures including synchroni

Julyan H. E. Cartwright, Diego L. Gonzalez, Oreste Piro

We investigate the hierarchical structure of three-frequency resonances in nonlinear dynamical systems with three interacting frequencies. We hypothesize an ordering of these resonances based on a generalization of the Farey tree organization from two frequencies to three. In experiments and numerical simulations we demonstrate that our hypothesis describes

Oscar Calvo, Julyan H. E. Cartwright

We introduce the idea of the fuzzy control of chaos: we show how fuzzy logic can be applied to the control of chaos, and provide an example of fuzzy control used to control chaos in Chua's circuit.

Hendrik Schatz, Lars Bildsten, Andrew Cumming, Michael Wiescher

We calculate the nucleosynthesis during stable nuclear burning on an accreting neutron star. This is appropriate for weakly magnetic neutron stars accreting at near-Eddington rates in low mass X-ray binaries, and for most accreting X-ray pulsars. We show that the nuclear burning proceeds via the rapid proton capture process (rp process), and makes nuclei far

E. Lastennet, D. Valls-Gabaud, T. Lejeune, E. Oblak

Three binary systems in the Hyades open cluster (51 Tau, V818 Tau, and $θ^2$ Tau}, with known metallicity and good Johnson photometric data are used to test the validity of three independent sets of stellar evolutionary tracks. A statistical method is described and applied to the colour-magnitude diagram of the six selected components, giving rise to $χ^2$-c

J. Greiner, W. Voges, Th. Boller, D. Hartmann

We report on the status of our search for X-ray afterglows of gamma-ray bursts (GRBs) using the ROSAT all-sky survey data. The number of potential X-ray afterglow candidates with respect to the expected number of beamed GRBs allows to constrain the relative beaming angles of GRB emission and afterglow emission at about 1-5 hrs after the GRB.

Hale V. Bradt, Donald A. Smith

The RXTE/ASM has detected and positioned 14 confirmed GRB bursts (at this writing, Jan. 1999) including six whose positions were comunicated to the community 2 to 32 hours after the burst. Two of these latter bursts led to measurements of optical red shifts but one, despite an easily detected x-ray afterglow, produced no detectable optical or radio afterglow

Andisheh Mahdavi

I show that the cluster LX-sigma relation should be sensitive to cosmologies with a scale-free power spectrum of initial density fluctuations, P(k) ~ k^n. I derive the dependence, and argue that a conservative interpretation of current observations implies n < -2.0 and n < -1.1 at the one-sided 90% and 99% confidence levels, respectively. This result, which

Evan Scannapieco, Joseph Silk, Jonathan C. Tan

We consider the effect of lensing by galaxy clusters on the angular distribution of submillimeter wavelength objects. While lensing does not change the total flux and number counts of submillimeter sources, it can affect the number counts and fluxes of flux-limited samples. Therefore imposing a flux cut on point sources not only reduces the overall Poisson n

J. M. Laming

The plasma theory of electrostatic waves generated collisionlessly when neutrinos pass through degenerate electrons is developed. It is consistent with the results of calculations using quantum statistical field theory in the degenerate limit for kinetic instabilities, and using this formalism reactive instabilities may also be treated. For all neutrino dist

J. F. Gallimore, S. A. Baum, C. P. O&#39;Dea, A. Pedlar

Active galaxies are thought to be both fueled and obscured by neutral gas removed from the host galaxy and funneled into a central accretion disk. We performed a VLA imaging survey of 21 cm absorption in Seyfert and starburst nuclei to study the neutral gas in the near-nuclear environment. With the exception of NGC 4151, the absorbing gas traces 100 pc scale

Javier Gorgas, Nicolas Cardiel, Santos Pedraz, Jesus Gonzalez

Empirical fitting functions, describing the behaviour of the λ4000 Åbreak, D_4000, in terms of effective temperature, metallicity and surface gravity, are presented. For this purpose, the break has been measured in 392 stars from the Lick/IDS Library. We have followed a very detailed error treatment in the reduction and fitting procedures, allowing for a rel

Tigran G. Arshakian, Malcolm S. Longair

An asymmetric relativistic model for FRII radio sources is described which takes account of both relativistic effects and intrinsic/environmental asymmetries to explain the observed structural asymmetry of their radio lobes. A key feature of the model is jet-sidedness, which can now be determined for about 80% of the FRII sources in the 3CRR complete sample.

J. Schneider, M. N. Celerier

The existence of stars and galaxies reqires cosmological models with an inhomogeneous matter and radiation distribution. But in these models the initial singularity surface t_0(r) is in general homogeneous (independent of r). In this second paper of a series devoted to an inhomogeneous Big Bang singularity, we investigate the cosmic microwave background radi

M. Guainazzi, G. Matt, L. A. Antonelli, L. Bassani

We present a X-ray spectroscopic study of the bright Compton-thick Seyfert 2s NGC1068 and the Circinus Galaxy, performed with BeppoSAX. Matt et al. (1997 and 1998) interpreted the spectrum above 4 keV as the superposition of Compton reflection and warm plasma scattering of the nuclear radiation. When this continuum is extrapolated downwards to 0.1 keV, furth

C. Hagmann

The standard Big-Bang theory predicts a cosmic neutrino background with an average number density of $\sim 100/cm^3$ per flavor. The most promising way of its detection is measuring the feeble ``neutrino wind&#39;&#39; forces exerted on macroscopic targets. The expected acceleration is $\sim 10^{-23} cm/s^2$ for Dirac neutrinos with a local number density $\

Thibaut Lery, J. Heyvaerts, S. Appl, C. A. Norman

The asymptotic structure of outflows from rotating magnetized objects confined by a uniform external pressure is calculated. The flow is assumed to be perfect MHD, polytropic, axisymmetric and stationary. The well known associated first integrals together with the confining external pressure, which is taken to be independent of the distance to the source, de

Israel Quiros

The notion of geometrical duality is discussed in the context of both Brans-Dicke theory and general relativity. It is shown that, in some particular solutions, the spacetime singularities that arise in usual Riemannian general relativity may be avoided in its dual representation (Weyl-type general relativity). This dual representation provides a singularity

S. Bar-Shalom, J. Wudka

We perform a global analysis of the sensitivity of LEP2 and e^+e^- colliders with a c.m. energy in the range 500 - 2000 GeV to new flavor-changing single top quark production in the effective Lagrangian approach. The processes considered are sensitive to new flavor-changing effective vertices such as Ztc, htc, four-Fermi tcee contact terms as well as a right

Antonio Puente, Llorens Serra

We apply the time-dependent local-spin-density approximation as general theory to describe ground states and spin-density oscillations in the linear response regime of two-dimensional nanostructures of arbitrary shape. For this purpose, a frequency analysis of the simulated real-time evolution is performed. The effect on the response of the recently proposed

Lung-Yih Chiang, Peter Coles

The Fourier transform of cosmological density perturbations can be represented in terms of amplitudes and phases for each Fourier mode. We investigate the phase evolution of these modes using a mixture of analytical and numerical techniques. Using a toy model of one-dimensional perturbations evolving under the Zel&#39;dovich approximation as an initial motiv

S. Pastor, J. Segura, V. B. Semikoz, J. W. F. Valle

The scattering of solar neutrinos on electrons may reveal their CP properties, which are particularly sensitive to their Majorana nature. The cross section is sensitive to the neutrino dipole moments through an interference of electro-magnetic and weak amplitudes. We show how future solar neutrino experiments with good angular resolution and low energy thres

Arbab I. Arbab

We have considered a cosmological model with a phenomenological model for the cosmological constant of the form $Λ=\bt\fr{\ddot R}{R}$, $ \bt$ is a constant. For age parameter consistent with observational data the Universe must be accelerating in the presence of a positive cosmological constant. The minimum age of the Universe is $H_0^{-1}$, where $H_0$ is

S. M. Croom, T. Shanks

We investigate the anti-correlation between faint high redshift QSOs and low redshift galaxy groups found by Boyle, Fong & Shanks (1988), on the assumption that it is caused by gravitational lensing of a flat QSO number count, rather than any other systematic effect (e.g dust). An isothermal sphere lens model, requires a velocity dispersion of 1286+72-91 km/

Sandro Ambrosanio, Grahame A. Blair

We consider the phenomenology of a class of gauge-mediated supersymmetry (SUSY) breaking (GMSB) models at a e+e- Linear Collider (LC) with c.o.m. energy up to 500 GeV. In particular, we refer to a high-luminosity (L ~ 3 x 10^34 cm^-2 s^-1) machine, and use detailed simulation tools for a proposed detector. Among the GMSB-model building options, we define a s

Ramon Aguado, Leo P. Kouwenhoven

We propose a measurement set-up for detecting quantum noise over a wide frequency range using inelastic transitions in a tunable two-level system as a detector. The frequency-resolving detector consists of a double quantum dot which is capacitively coupled to the leads of a nearby mesoscopic conductor. The inelastic current through the double quantum dot is

ZEUS Collaboration

The e^+p neutral-current deep inelastic scattering differential cross-sections $dσ/dQ^2$, for Q^2 > 400 GeV^2, $dσ/dx$ and $dσ/dy$, for Q^2 > 400, 2500 and 10000 GeV^2, have been measured with the ZEUS detector at HERA. The data sample of 47.7 pb^-1 was collected at a center-of-mass energy of 300 GeV. The cross-section, $dσ/dQ^2$, falls by six orders of magn

M. Bertolini, P. Fre`, M. Trigiante

In this paper we construct the 5 parameter generating solution of N=8 BPS regular supergravity black holes as a five parameter solution of the N=2 STU model. Our solution has a simpler form with respect to previous constructions already appeared in the literature and moreover, through the embedding [SL(2)]^3\subset SU(3,3)\subset E_{(7)7} discussed in previo

Alexander Rokhlenko, Joel L. Lebowitz

We study the time evolution of the wave function of a particle bound by an attractive $δ$-function potential when it is subjected to time dependent variations of the binding strength (parametric excitation). The simplicity of this model permits certain nonperturbative calculations to be carried out analytically both in one and three dimensions. Thus the surv

C. Satriano

Using a sample of 38.5 million underground muons collected by the MACRO detector we have performed an all-sky search for pointlike sources producing excesses of muons above the expected background. The d.c. muon flux upper limit at the Earth coming from selected sources is of the order of 10^-13 cm^-2 s^-1 or less. Futhermore we discuss searches for possible

M. Gajdzik, C. Suergers, M. Kelemen, H. v. Loehneysen

The structural and magnetic properties of Mn5Ge3Cx films prepared at elevated substrate temperatures TS are investigated. In particular, films with x >= 0.5 and TS = 680 K exhibit a strongly enhanced Curie temperature TC = 440 K compared to Mn5Ge3 with TC = 304 K. Structural analysis of these films suggests that the carbon is interstitially incorporated into

Gabriela Barenboim, Galit Eyal, Yosef Nir

Recently, the CDF collaboration has reported a measurement of the CP asymmetry in the $B\toψK_S$ decay: $a_{ψK_S}=0.79^{+0.41}_{-0.44}$. We analyze the constraints that follow from this measurement on the size and the phase of contributions from new physics to $B-\barB$ mixing. Defining the relative phase between the full $M_{12}$ amplitude and the Standard

Michal Horodecki

We consider the problem of the optimal compression rate in the case of the source producing mixed signal states within the {\it visible} scheme (where Alice, who is to compress the signal, can know the identities of the produced states). We show that a simple strategy based on replacing the signal states with their {\it extensions} gives {\it optimal} compre

Michele Cini, Adalberto Balzarotti, Gianluca Stefanucci

We study the Cu_{5}O_{4} cluster by exact diagonalization of a three-band Hubbard model and show that bound electron or hole pairs are obtained at appropriate fillings, and produce superconducting flux quantisation. The results extend earlier cluster studies and illustrate a canonical transformation approach to pairing that we have developed recently for the

P. Binder, D. Abraimov, A. V. Ustinov, S. Flach

We report on the observation of spatially-localized excitations in a ladder of small Josephson junctions. The excitations are whirling states which persist under a spatially-homogeneous force due to the bias current. These states of the ladder are visualized using a low temperature scanning laser microscopy. We also compute breather solutions with high accur

Ian Smail, R. J. Ivison, J. -P. Kneib, L. L. Cowie

We use deep ground-based imaging in the near-IR to search for counterparts to the luminous submm sources in the catalog of Smail et al (1998). For the majority of the submm sources the near-IR imaging supports the counterparts originally selected from deep optical images. However, in two cases (10% of the sample) we find a relatively bright near-IR source cl

Holger Frahm, Gerald Bedürftig

We study singularities in the I-V characteristics for sequential tunneling from resonant localized levels (e.g. a quantum dot) into a one dimensional electron system described by a Hubbard model. Boundary conformal field theory together with the exact solution of the Hubbard model subject to boundary fields allows to compute the exponents describing the sing

Yasushi Abe, Kouji Segawa, Yoichi Ando

The temperature dependence of the Hall coefficient is measured with a high accuracy in a series of Zn-doped YBCO_{6.78} crystals with the Zn concentration from 0% to 1.3%. We found that the cotangent of the Hall angle, cot(θ_H), starts to deviate upward from the T^2 dependence below T_0 (which is roughly 130 K), regardless of the Zn concentration. We discuss

Lars Kjaergaard, Paul Mansfield

We illustrate a method for improving Renormalisation Group improved perturbation theory by calculating the infrared central charge of a perturbed conformal field theory. The additional input is a dispersion relation that exploits analyticity of the energy-momentum tensor correlator.

S. Abdullin, F. Charles

We study the discovery potential of the CMS detector for the scalar leptoquark pair production at the LHC. Present and future exclusion limits are considered. We find that the maximal leptoquark mass reach is about 1.47 TeV for the branching ratio of Br(LQ_l -> l q)=100 %, while for Br(LQ_l -> l q)=50 % the upper limit is 1.2 TeV for an integrated luminosity

Tammo Diemer, Mark J Hadley

A new class of electrically charged wormholes is described in which the outer two sphere is not spanned by a compact coorientable hypersurface. These wormholes can therefore display net electric charge from the source free Maxwell&#39;s equation. This extends the work of Sorkin on non-space orientable manifolds, to spacetimes which do not admit a time orient

Prakash Mathews, P. Poulose, K. Sridhar

Theories with large extra dimensions predict an infinite tower of Kaluza-Klein states in the 1 TeV range, which can consequently have significant implications for experimental observables. One such observable, which gets affected by the exchange of spin-2 Kaluza-Klein particles, is the t t(bar) production cross-section in photon-photon collisions at NLC ener

M. N. Achasov, S. E. Baru, A. V. Bozhenok, D. A. Bukin

The process e^+e^- ->mu^+mu^- has been studied with SND detector at VEPP-2M e^+e^- collider in the vicinity of phi(1020) resonance. The product of branching ratios of phi meson into leptons \sqrt{B(phi->mu^+mu^-) B(phi-> e^+e^-)}=(3.14+-0.22+-0.14)x10^{-4} was measured from the interference in the cross section of the process e^+e^- ->mu^+mu^-. The branching

Dirk Siersma, Mihai Tibar

We study vanishing cycles naturally attached to a meromorphic function with isolated singularities, in both local and global settings.

Akio Sugamoto, Yadong Yang

We first investigate the semileptonic annihilation decay B_c \to η&#39; lνin QCD. We find that the $η&#39;$ momentum distribution is peaked within its small recoil region due to the loop effects. The branching ratio is estimated to be $ Br(B_c \to η&#39; lν)=1.6\times 10^{-4}$ for $l=μ,e$, which is accessible at CERN LHC.

Armen Sedrakian, Alex Dieperink

We calculate the rate of energy radiation by bremsstrahlung of neutrino pairs by baryons in neutron stars employing a transport model in which neutrinos couple to baryons with spectral width. The coherence effects, which are included by computing the self energies with fully dressed propagators, lead to the Landau-Pomeranchuk-Migdal suppression of the neutri

Reinaldo Gleiser, Gaurav Khanna, Jorge Pullin

The conformally flat families of initial data typically used in numerical relativity to represent boosted black holes are not those of a boosted slice of the Schwarzschild spacetime. If such data are used for each black hole in a collision, the emitted radiation will be partially due to the ``relaxation&#39;&#39; of the individual holes to ``boosted Schwarzs

Adan Cabello

Two proofs are presented which show that quantum mechanics is incompatible with the following assumption: all possible correlations between subsystems of an individual isolated composite quantum system are contained in the initial quantum state of the whole system, although just a subset of them is revealed by the actual experiment.

H. Jirari, H. Kröger, X. Q. Luo, K. J. M. Moriarty

We construct an effective Hamiltonian via Monte Carlo from a given action. This Hamiltonian describes physics in the low energy regime. We test it by computing spectrum, wave functions and thermodynamical observables (average energy and specific heat) for the free system and the harmonic oscillator. The method is shown to work also for other local potentials

K. B. Korotchenko

It is shown in the present work that the three-dimensional trajectories of an electrical test particle in potential fields may be regarded as geodesic lines lying on isotropic surfaces of some four-dimensional configurational space, the connection of which has tortion, while the transference is nonmetric.

V. S. Vanyashin

The use of coordinate variables with independent physical boundaries -- Heron variables -- is proposed for the 3-body problem. The ansatz is given for variational trial wave functions without local energy infinities at the Coulomb singularities

Juhi-Lian Julian Ting

This is a letter to editor, about a previously published paper and comments.

V. S. Timoteo, C. L. Lima

Using a q-deformed fermionic algebra we perform explicitly a deformation of the Nambu-Jona-Lasinio (NJL) Hamiltonian. In the Bogoliubov-Valatin approach we obtain the deformed version of the functional for the total energy, which is minimized to obtain the corresponding gap equation. The breaking of chiral symmetry and its restoration in the limit $q \to 0$

Wojciech Broniowski, Wojciech Florkowski, Brigitte Hiller

We calculate the width for the omega -> pi pi decay in nuclear matter in a hadronic model including mesons, nucleons and Delta isobars. We find a substantial width of the longitudinally polarized omega modes, reaching ~100MeV for mesons moving suitably fast with respect to the nuclear medium.

Giovanni Landi

We give a unifying description of all inequivalent vector bundles over the 2-dimensional sphere $S^2$ by constructing suitable global projectors $p$ via equivariant maps. Each projector determines the projective module of finite type of sections of the corresponding complex rank 1 vector bundle over $S^2$. The canonical connection $\nabla = p \circ d$ is use

Tomek Bartoszynski

A combinatorial characterization of measurable filters on a countable set is found. We apply it to the problem of measurability of the intersection of nonmeasurable filters.

Tomek Bartoszynski, Saharon Shelah

We study the relationship between the sigma-ideal generated by closed measure zero sets and the ideals of null and meager sets. We show that the additivity of the ideal of closed measure zero sets is not bigger than covering for category. As a consequence we get that the additivity of the ideal of closed measure zero sets is equal to the additivity of the id

Tomek Bartoszynski, Haim Judah, Saharon Shelah

We conclude the discussion of additivity, Baire number, uniformity and covering for measure and category by constructing the remaining 5 models. Thus we complete the analysis of Cichon&#39;s diagram.

Tomek Bartoszynski, Marion Scheepers

We consider ``meager analogues&#39;&#39; of classical covering properties of Menger, Hurewicz and Rothberger. We show that Borel images of sets having ``our&#39;&#39; covering properties have these classical covering properties.

Tomek Bartoszynski, Haim Judah

The main goal of this paper is to generalize several results concerning cardinal invariants to the statements about the associated families of sets. We also discuss the relationship between the additive properties of sets and their Borel images. Finally, we present estimates for the size of the smallest set which is not strongly meager.

Tomek Bartoszynski, Marion Scheepers

We obtain game-theoretic characterizations for meagerness and rareness of filters on a countable set.

Tomek Bartoszynski, Marion Scheepers

We show that several classes of sets, like N_0-sets, Arbault sets, N-sets and pseudo-Dirichlet sets are closed under adding sets of small size.

Tomek Bartoszynski, Haim Judah

We study the ideal of meager sets and related ideals.

Tomek Bartoszynski, Ireneusz Reclaw

We present two constructions of gamma-sets which are large in sense of category.

Tomek Bartoszynski

It is shown that it is consistent with ZFC that every uncountable set can be continuously mapped onto a splitting family.

Tomek Bartoszynski

The existence of an uncountable family of nonmeager filter whose intersection is meager is consistent with MA(Suslin)

Nils R. Scheithauer

We show that the physical states of a 10 dimensional superstring moving on a torus form a generalized Kac-Moody superalgebra. This gives the first explicit realizations of these algebras. For a special torus the denominator function of this algebra is an automorphic form so that we can determine the simple roots. We call this algebra the fake monster superal

U. Hertrich-Jeromin, I. McIntosh, P. Norman, F. Pedit

A discrete conformal map (DCM) maps the square lattice to the Riemann sphere such that the image of every irreducible square has the same cross-ratio. This paper shows that every periodic DCM can be determined from spectral data (a hyperelliptic compact Riemann surface, called the spectral curve, equipped with some marked points). Each point of the map corre

Yuri A. Rylov

A new method of metric space investigation, based on classification of its finite subspaces, is suggested. It admits to derive information on metric space properties which is encoded in metric. The method describes geometry in terms of only metric. It admits to remove constraints imposed usually on metric (the triangle axiom and nonnegativity of the squared

Imre Bárány, Jean-Michel Kantor

Given a lattice polytope $P$ (with underlying lattice $\lo$), the universal counting function $\uu_P(\lo&#39;)=|P\cap \lo&#39;|$ is defined on all lattices $\lo&#39;$ containing $\lo$. Motivated by questions concerning lattice polytopes and the Ehrhart polynomial, we study the equation $\uu_P=\uu_Q$.

Tatsuhiro Minagawa

In this article, we prove that any $\Bbb Q$-factorial weak Fano 3-fold with only terminal singularities has a smoothing.

Tatsuhiro Minagawa

In this article, we prove that any Q-Calabi-Yau 3-fold with only ordinary terminal singularities and any Q-Fano 3-fold of Fano index 1 with only terminal singularities have Q-smoothings.

Hiromichi Takagi

This is a revised version of my paper which appeared in J. Math. Sci. Univ. Tokyo. We prove that for a flipping contraction from a Gorenstein terminal 4-fold, the pull back of a general hyperplane section of the down-stair has only canonical singularities. Based on this fact and using Siu-Kawamata-Nakayama&#39;s extension theorem [Si], [Kaw4], [Kaw5] and [Na

Tobias Ekholm, Ola Weistrand

A differential geometric characterization of the braid-index of a link is found. After multiplication by 2pi, it equals the infimum of the sum of total curvature and total absolute torsion over holonomic representatives of the link. Upper and lower bounds for the infimum of total curvature over holonomic representatives of a link are given in terms of its br

Lars Grüne, Eduardo D. Sontag, Fabian R. Wirth

In this paper we show that uniformly global asymptotic stability for a family of ordinary differential equations is equivalent to uniformly global exponential stability under a suitable nonlinear change of variables. The same is shown for input-to-state stability and input-to-state exponential stability, and for input-to-state exponential stability and a non

Igor Bandos, Wolfgang Kummer

We propose a method to obtain a manifestly supersymmetric action functional for interacting brane systems. It is based on the induced map of the worldvolume of low-dimensional branes into the worldvolume of the space-time filling brane ((D-1)-brane), which may be either dynamical or auxiliary, and implies an identification of Grassmann coordinate fields of l

F. Vian

The purpose of the present thesis is the implementation of symmetries in the Wilsonian Exact Renormalization Group (ERG) approach. After recalling how the ERG can be introduced in a general theory (i.e. containing both bosons and fermions, scalars and vectors) and having applied it to the massless scalar theory as an example of how the method works, we discu

J. Bogaerts, A. Sevrin, S. van der Loo, S. Van Gils

Whenever the N=(2,2) supersymmetry algebra of non-linear sigma-models in two dimensions does not close off-shell, a holomorphic two-form can be defined. The only known superfields providing candidate auxiliary fields to achieve an off-shell formulation are semi-chiral fields. Such a semi-chiral description is only possible when the two-form is constant. Usin

Krzysztof A. Meissner, Hans Peter Nilles, Marek Olechowski

A compactification of 11-dimensional supergravity with two (or more) walls is considered. The whole tower of massive Kaluza-Klein modes along the fifth dimension is taken into account. With the sources on the walls, an explicit composition in terms of Kaluza-Klein modes of massless gravitino (in the supersymmetry preserving case) and massive gravitino (in th

Ephraim Fischbach, Dennis E. Krause

The exchange of light pseudoscalar quanta between fermions leads to long-range spin-dependent forces in order g^2, where g is the pseudoscalar-fermion coupling constant. We demonstrate that laboratory bounds on the Yukawa couplings of pseudoscalars to nucleons can be significantly improved using results from recent equivalence principle experiments, which ar

V. Pleitez

Here we analyze the relation between the search for muonium to antimuonium conversion and the 331 model with doubly charged bileptons. We show that the constraint on the mass of the vector bilepton obtained by experimental data can be evaded even in the minimal version of the model since there are other contributions to that conversion. We also discuss the c

D. London, N. Sinha, R. Sinha

The b -> d penguin amplitude receives contributions from internal u, c and t-quarks. We show that it is impossible to measure the weak phase of any of these penguin contributions without theoretical input. However, it is possible to obtain the weak phase if one makes a single assumption involving the hadronic parameters. With such an assumption, one can test

J. Bellandi, J. R. Fleitas, J. Dias de Deus

We present in this paper a calculation of the average proton-nucleus ine- lasticity. Using an Iterative Leading Particle Model and the Glauber model, we relate the leading particle distribution in nucleon-nucleus interactions with the respective one in nucleon-proton collisions. To describe the leading particle distribution in nucleon-proton collisions, we u

Takahiro Okabe, Michiyasu Nagasawa

The formation probability of multiple winding topological defects is calculated by phase and flux distribution analysis based on the Kibble mechanism. The core size of defects is taken into account so that when it is much larger than the correlation length of the Higgs field, high winding configuration can be realized. For example, if the self coupling const

Mokhtar Elchikh, Jean-Marc Richard

It is recalled that spin-observables in the strangeness-exchange reaction $\bar{p}{p} \to \barΛΛ$ are not independent but are related to each other by simple algebraic relations. This provides constraints on the existing data on polarization and spin-correlation coefficients, and also on the forthcoming data obtained using a polarized proton target.

A. Misaki, V. A. Naumov, T. S. Sinegovskaya, S. I. Sinegovsky

Energy spectra and zenith angle distributions of atmospheric muons are calculated for the depths of operation of large underwater neutrino telescopes. The estimation of the prompt muon contribution is performed with three approaches to charm hadroproduction: recombination quark-parton model, quark-gluon string model, and perturbative QCD based models. Calcul

Bugra Borasoy, Barry R. Holstein

We examine the importance of J^P = 1/2^+, 1/2^- resonances for weak nonleptonic Omega^- decays within the framework of chiral perturbation theory. The spin-1/2 resonances are included into an effective theory and tree contributions to the Omega^- decays are calculated. We find significant contributions to the decay amplitudes and satisfactory agreement with