March 2001 arXiv papers

Nicholas Neary, Mustapha Ishak, Kayll Lake

The Tolman VII solution is an exact static spherically symmetric perfect fluid solution of Einstein's equations that exhibits a surprisingly good approximation to a neutron star. We show that this solution exhibits trapped null orbits in a causal region even for a tenuity (total radius to mass ratio) $> 3$. In this region the dynamical part of the potent

Hiroyuki Abe, Tomohiro Inagaki, Taizo Muta

The dynamical fermion mass generation on the D3-brane in the Randall-Sundrum space-time is discussed in a model with bulk fermions in interaction with fermions on the branes. It is found that the dynamical fermion masses are generated at the natural (R.-S.) radius of the compactified extra space and may be made small compared with masses of the Kaluza-Klein

Zhangbu Xu, the STAR Collaboration

We report on the observed signals of ${K^{\star0}(892)}\toπK$ and $ϕ(1020)\to K^{+}K^{-}$ using the mixed-event method with powerful statistics from the large acceptance and highly efficient STAR TPC. Preliminary results from the first observation of such states from the year-one STAR data in $\sqrt{s_{NN}}=130$ GeV Au-Au collisions are presented. The $K^{\s

G. Brunetti, M. Cappi, G. Setti, L. Feretti

Inverse Compton (IC) scattering of nuclear photons with relativistic electrons in the lobes of powerful radio galaxies and quasars can give detectable extended X-ray emission from the radio lobes if relativistic electrons with a Lorentz factor gamma about 300 are present (Brunetti, Setti, Comastri 1997). In general these electrons are not detected since they

X. K. Chen, M. J. Konstantinovic, J. C. Irwin, D. D. Lawrie

We have measured the Raman spectra of polycrystalline MgB$_{2}$ from 25 {\cm} to 1200 {\cm}. When the temperature was decreased below the superconducting transition temperature $T_c$, we observed a superconductivity-induced redistribution in the electronic Raman continuum. Two pair-breaking peaks appear in the spectra, suggesting the presence of two supercon

D. Reiss, K. Abich, W. Neuhauser, Ch. Wunderlich

We study cooling of the collective vibrational motion of two 138Ba+ ions confined in an electrodynamic trap and irradiated with laser light close to the resonances S_1/2-P_1/2 (493 nm) and P_1/2-D_3/2 (650 nm). The motional state of the ions is monitored by a spatially resolving photo multiplier. Depending on detuning and intensity of the cooling lasers, mac

O. P. Sushkov

Short length quantum wires (quantum contacts) exhibit a conductance structure at the value of conductance close to 0.7 \times 2e^2/h. The structure is also called the conductance anomaly. In longer contacts the structure evolves to the lower values of conductance. We demonstrate that this structure is related to the development of charge density waves within

ZEUS Collaboration

The photoproduction of prompt photons, together with an accompanying jet, has been measured with the ZEUS detector at HERA using an integrated luminosity of 38.6 pb^{-1}. A study of the effective transverse momentum, k_T, of partons in the proton, as modelled within the framework of the PYTHIA Monte Carlo, gives a value of k_T = 1.69+/-0.18 ^{+0.18}_{-0.20}

Masato Koashi, Nobuyuki Imoto

The amount of entanglement necessary to teleport quantum states drawn from general ensemble $\{p_i,ρ_i\}$ is derived. The case of perfect transmission of individual states and that of asymptotically faithful transmission are discussed. Using the latter result, we also derive the optimum compression rate when the ensemble is compressed into qubits and bits.

Karl Svozil

In an experiment featuring nonlinear optics, delayed choice and EPR-type correlations, the possibility of faster-than-light communication appears not totally implausible. Attempts are put forward and discussed to refute this claim.

Mario Rabinowitz

There are countless examples in the history of science that not only were the laws of physics often incomplete and more limited in their domain of validity than was realized, but at times they missed the mark completely. Despite this, our collective memory is often short on such matters, focusing on present triumphs and quickly forgetting past failures. This

A. G. Ramm

If $f(x,k)$ is the Jost solution and $f(x) = f(0,k)$, then the $I$-function is $I(k) := \frac{f^\prime(0,k)}{f(k)}$. It is proved that $I(k)$ is in one-to-one correspondence with the scattering triple ${\mathcal S} :=\{S(k), k_j, s_j, \quad 1 \leq j \leq J\}$ and with the spectral function $ρ(λ)$ of the Sturm-Liouville operator $l= -\frac{d^2}{dx^2} + q(x)$

Wei-Dong Ruan

In this paper we summarize our recent work in the construction of Lagrangian torus fibrations for Calabi-Yau hypersurfaces in toric varieties and the symplectic Strominger-Yau-Zaslow conjecture, together with some new development. It is submittded to the Proceedings of the Conference in Symplectic Geometry and Mirror Symmetry held in KIAS, Seoul, Korea. The

C. Anghel, N. Manolache

In this paper, using the Atiyah-Ward equivalence and a theorem of Hitchin, one makes to correspond to certain bundles on the projective space, which are extensions of instanton bundles (in particular, these new bundles may have the first Chern class not congruent to 0 modulo the rank), bundles on the grassmanian Gr(2,4) or on the sphere S4, equiped with cert

Joachim Cuntz

We give a survey of cyclic homology/cohomology theory including a detailed discussion of cyclic theories for various classes of topological algebras. We show how to associate cyclic classes with Fredholm modules and $K$-theory classes and how to construct a completely general bivariant Chern-Connes character from bivariant $K$-theory to bivariant cyclic theo

Gentiana Danila

We compute some cohomology spaces for the symmetric power of the tautological bundle tensor the determinant bundle on the punctual Hilbert scheme of a complex smooth projective surface.

Ana Bravo, Orlando Villamayor

Let $X$ be a closed subscheme embedded in a scheme $W$ smooth over a field ${\bf k}$ of characteristic zero, and let ${\mathcal I}(X)$ be the sheaf of ideals defining $X$. Assume that the set of regular points of $X$ is dense in $X$. We prove that there exists a proper, birational morphism, $π: W_r\longrightarrow W$, obtained as a composition of monoidal tra

Stefano Bellucci, Anton Galajinsky

We study classical N=2 string within the framework of the N=4 topological formalism by Berkovits and Vafa. Special emphasis is put on the demonstration of a classical equivalence of the theories and the construction of an action for the N=4 topological string. The SO(2,2) Lorentz invariance missing in the conventional Brink--Schwarz action for the N=2 string

Davide Fioravanti, Marco Rossi

A generalization of the Yang-Baxter algebra is found in quantizing the monodromy matrix of two (m)KdV equations discretized on a space lattice. This braided Yang-Baxter equation still ensures that the transfer matrix generates operators in involution which form the Cartan sub-algebra of the braided quantum group. Representations diagonalizing these operators

J. Casahorran

We consider in detail how the quantum-mechanical tunneling phenomenon occurs in a well-behaved octic potential. Our main tool will be the euclidean propagator just evaluated between two minima of the potential at issue. For such a purpose we resort to the standard semiclassical approximation which takes into account the fluctuations over the instantons, i.e.

Sonja Kabana

We address the flavour composition along the border between the hadronic and the quark-gluon plasma phases of QCD. The ratio of strange to up and down antiquarks ($λ_s$) produced in partic le and nuclear collisions, is found to increase in collisions with initially reached energy density ($ε_i$) up to $ε_{crit}$ $\sim$ 1 GeV/$fm^3$. Above this value it decre

Camil Demetrescu, Giuseppe F. Italiano

In this paper we introduce a general framework for casting fully dynamic transitive closure into the problem of reevaluating polynomials over matrices. With this technique, we improve the best known bounds for fully dynamic transitive closure. In particular, we devise a deterministic algorithm for general directed graphs that achieves $O(n^2)$ amortized time

I. O. Vakarchuk, A. A. Rovenchak

In this paper we propose five different modifications of the hard sphere potential for the modeling a short-range repulsion and the calculation of thermodynamic and transport properties of liquid He4. We calculate the potential energy, the total energy, and the sound velocity at T=0 K. It is shown that three of the proposed potentials give a satisfactory des

N. A. Taylanov

The thermomagnetic instability of the critical state in superconductors is analysed with account of the dissipation and dispersion. The possibility is demonstrated of the existance of a nonlinear shok wave describing the final stage of the instability evolution in a superconductor. The structures possess a finite-amplitude and propagate at a constant velocit

Keshav N. Shrivastava

We introduce s.n where n is the unit vector in the direction of the radius vector and s is the spin, which along with the velocity forms a spin-orbit interaction of the order of v/c whereas the usual spin-orbit interaction is of the order of the square of v/c. The effective fractional charges obtained from this interaction are in good agreement with the expe

G. Sambandamurthy, K. Das Gupta, N. Chandrasekhar

We have studied the insulator-superconductor transition (IST) by tuning the thickness in quench-condensed $Bi$ films. The resistive transitions of the superconducting films are smooth and can be considered to represent "homogeneous" films. The observation of an IST very close to the quantum resistance for pairs, $R_{\Box}^N \sim h/4e^2$ on several su

Chun-Chung Chen, Marcel den Nijs

We present a directed unloading sand box type avalanche model, driven by slowly lowering the retaining wall at the bottom of the slope. The avalanche propagation in the two dimensional surface is related to the space-time configurations of one dimensional Kardar-Parisi-Zhang (KPZ) type interface growth dynamics. We express the scaling exponents for the avala

Greg Huey, James E. Lidsey

Inflationary cosmology is developed in the second Randall-Sundrum braneworld scenario, where the accelerated expansion arises through potentials that are too steep to drive inflation in conventional cosmology. A relationship between the scalar and tensor perturbation spectra is derived that is independent of both the inflaton potential and the brane tension.

S. C. Gallagher, J. C. Charlton, S. D. Hunsberger, D. Zaritsky

Analysis of Hubble Space Telescope/Wide Field Planetary Camera 2 images of Stephan&#39;s Quintet, Hickson Compact Group 92, yielded 115 candidate star clusters (with V-I < 1.5). Unlike in merger remants, the cluster candidates in Stephan&#39;s Quintet are not clustered in the inner regions of the galaxies; they are spread over the debris and surrounding area

J. Ventura, A. Y. Potekhin

The thermal structure of neutron star envelopes is discussed with emphasis on analytic results. Recent progress on the effect of chemical constitution and high magnetic fields on the opacities and the thermal structure is further reviewed in view of the application to pulsar cooling and magnetars.

James E. Taylor, Julio F. Navarro

We examine the coarse-grained phase-space density profiles of a set of recent, high-resolution simulations of galaxy-sized Cold Dark Matter (CDM) halos. Over two and a half decades in radius the phase-space density closely follows a power-law, $ρ/σ^3 \propto r^{-α}$, with $α= 1.875$. This behaviour matches the self-similar solution obtained by Bertschinger f

Clayton Heller, Isaac Shlosman, Peter Englmaier

We find that nuclear rings in barred galaxies can be subject to a new type of non-self-gravitational dynamical instability. The instability leads to the formation of gaseous molecular bars with pattern speeds which are substantially slower than speeds of the primary stellar bars. This spectacular decoupling of nuclear bars from the underlying gravitational p

Rajesh Gopakumar, Matthew Headrick, Marcus Spradlin

We find the moduli space of multi-solitons in noncommutative scalar field theories at large theta, in arbitrary dimension. The existence of a non-trivial moduli space at leading order in 1/theta is a consequence of a Bogomolnyi bound obeyed by the kinetic energy of the theta=infinity solitons. In two spatial dimensions, the parameter space for k solitons is

A. V. Belitsky, A. Kirchner, D. Müller, A. Schäfer

We study twist-three effects in deeply virtual Compton scattering on an unpolarized spin-1/2 target. A careful definition of observables as Fourier moments w.r.t. the azimuthal angle allows for a clear separation of twist-two and -three effects. Although the latter are power suppressed, they give leading contributions to the twist-three asymmetries and do no

D. V. Nanopoulos, Raghavan Rangarajan

In this letter we explore the possibility of creating the baryon asymmetry of the universe during inflation and reheating due to the decay of a field associated with the inflaton. CP violation is attained by assuming that this field is complex with a phase that varies as the inflaton evolves. We consider chaotic and natural inflation scenarios. In the former

A. De Masi, P. A. Ferrari

Let $J(t)$ be the the integrated flux of particles in the symmetric simple exclusion process starting with the product invariant measure $ν_ρ$ with density $ρ$. We compute its rescaled asymptotic variance: \[ \lim_{t\to\infty} t^{-1/2} \V J(t) = \sqrt{2/π} (1-ρ)ρ\] Furthermore we show that $t^{-1/4}J(t)$ converges weakly to a centered normal random variable

Darwin Chang, R. N. Mohapatra

We discuss how CP symmetry can be broken geometrically through orbifold projections in hidden extra dimensions in the context of D-brane models for particle unifications. We present a few toy models to illustrate the idea and suggest ways to incorporate this technique in the context of realistic models.

Peter Kopietz, Tom Busche

We construct exact functional renormalization group (RG) flow equations for non-relativistic fermions in arbitrary dimensions, taking into account not only mode elimination but also the rescaling of the momenta, frequencies and the fermionic fields. The complete RG flow of all relevant, marginal and irrelevant couplings can be described by a system of couple

M. Uslenghi, L. Tommasi, A. Treves, V. Piirola

We report on UBVRI polarimetry of the recently identified Intermediate Polar 1WGA J1958.2+3232, carried out on 2000 August, 4-6 at the Nordic Optical Telescope. Circular polarization was detected in R and I bands with an increasing absolute mean value with wavelength. There is evidence of possible modulation of the circular polarization at twice the previous

Wang Xiang-Bin, Matsumoto Keiji, Tomita Akihisa

The partial transposition(PT) operation is an effecient tool in detecting the inseparability of a mixed state. We give an explicit formula for the PT operation for the continuous variable states in Fock space. We then give the necessary and sufficient condition for the positivity of Gaussian operators. Based on this, a number of creterions on the inseparabil

C. Le Mouël

In the MSSM, the Charge and Color Breaking (CCB) vacuum in the plane $(H_2,\tilde{t}_L, \tilde{t}_R)$ typically deviates largely from all D-flat directions, due to the large effects induced by the presence of the top quark Yukawa coupling. As a result, the critical CCB bound on the trilinear soft term $A_t$ becomes more restrictive than the D-flat bound $A_t

M. C. Bento, O. Bertolami, R. Rosenfeld

Working in the context of a proposal for collisional dark matter, we derive bounds on the Higgs boson coupling $g^{\prime}$ to a stable light scalar particle, which we refer to as phion ($ϕ$), required to solve problems with small scale structure formation which arise in collisionless dark matter models. We discuss the behaviour of the phion in the early uni

G. H. Arakelyan, A. Capella, A. B. Kaidalov, Yu. M. Shabelski

The process of baryon number transfer due to string junction propagation in rapidity is considered. It has a significant effect in the net baryon production in $pp$ collisions at mid-rapidities and an even larger effect in the forward hemisphere in the cases of $πp$ and $γp$ interactions. The results of numerical calculations in the framework of the Quark-Gl

M. Beccaria, F. M. Renard, C. Verzegnassi

We consider the separate effects on four fermion processes, in the TeV energy range, produced at one loop by Sudakov logarithms of universal and not universal kind, working in the &#39;t Hooft xi=1 gauge. Summing the various vertex and box contributions allows to isolate two quite different terms.The first one is a combination of vertex and box quadratic and

B. Machet, S. T. Petcov

We study the general dependence of mixing angles on heavy fermion masses when mass hierarchies exist among the fermions. For two generations and small Cabibbo angle, this angle is directly shown to scale like $μ_1/m_s \pm μ_2/m_c$, where $|μ_1| \ll m_s, |μ_2| \ll m_c$ are independent mass scales. For $n=3$ generations, we extend to the Yukawa matrices of $u$

Amir H. Fatollahi

We consider the matrix quantum mechanics of N D0-branes in the background of the 1-form RR field. It is observed that the transformations of matrix coordinates of D0-branes induce on the Abelian RR field symmetry transformations that are like those of non-Abelian gauge fields. The Lorentz-like equations of motion for matrix coordinates are derived. The field

V. Yu. Grishina, L. A. Kondratyuk, M. Buescher, W. Cassing

It is demonstrated that f_0-a_0 mixing can lead to a comparatively large isospin violation in the reactions pN -> da_0, pd -> ^3He/^3H a_0 and dd -> ^4He a_0 close to the corresponding production thresholds. The observation of such mixing effects is possible, e.g., by measuring the forward-backward asymmetry in the reaction pn -> d a_0^0 -> d eta pi^0.

CAPRICE Collaboration

We report on a new measurement of the cosmic ray antiproton spectrum. The data were collected by the balloon-borne experiment CAPRICE98 which was flown on 28-29 May 1998 from Fort Sumner, New Mexico, USA. The experiment used the NMSU-WIZARD/CAPRICE98 balloon-borne magnet spectrometer equipped with a gas Ring Imaging Cherenkov (RICH) detector, a time-of-fligh

G. Bonneau, P. Y. Casteill

We adress ourselves the question of the quantum equivalence of non abelian dualised $\si$-models on the simple example of the T-dualised $SU(2) \si$-model. This theory is classically canonically equivalent to the standard chiral $SU(2) \si$-model. It is known that the equivalence also holds at the first order in perturbations with the same $\be$ functions. H

Mihail Mintchev

We investigate quantum field theory in a bulk space with boundary, which represents a 3-brane. Both flat and anti-de Sitter backgrounds are considered. The basic idea is to keep local commutativity only on the brane, giving up this requirement in the bulk. We explore the consequences of this proposal, constructing a large family of nonlocal bulk fields, whos

Tobias Hurth, Thomas Mannel

We point out that a simple test of the mechanism of CP violation can be performed by a measurement of the CP asymmetries in exclusive and inclusive radiative rare decays. We show that the rate asymmetries $ΔΓ= Γ(B^- \to f γ) - Γ(B^+ \to \bar{f} γ)$} for certain final states $f$ can be predicted in a theoretically clean way. Some implications for $b \to s \el

M. Honda, T. Kajita, K. Kasahara, S. Midorikawa

A 3-dimensional calculation of atmospheric neutrinos flux is presented, and the results are compared with those of a 1-dimensional one. In this study, interaction and propagation of particles is treated in a 3-dimensional way including the curvature of charged particles due to the geomagnetic field, which is assumed to be a dipole field. The purpose of this

P. O. Mari, I. A. Campbell

We compare numerical estimates from different sources for the ordering temperature $T_g$ and the critical exponents of the Ising spin glass in dimension three with binomial ($\pm J$) interactions. Corrections to finite size scaling turn out to be important especially for parameters such as the Binder cumulant. For non-equilibrium parameters it is easier to a

Subir Ghosh

The Spinning Particle Model for anyon is analysed in the Batalin-Tyutin scheme of quantisation in extended phase space. Here additional degrees of freedom are introduced in the phase space such that all the constraints in the theory are rendered First Class that is commuting in the sense of Poisson Brackets. Thus the theory can be studied without introducing

Abraham Loeb

I show that neutral lithium couples strongly to the cosmic microwave background (CMB) through its 6708A resonant transition after it recombines at z~500. At observed wavelengths of <335 micron, the CMB anisotropies are significantly altered since the optical depth for resonant scattering by neutral lithium is substantial, of order 0.5. The scattering would s

H. Y. Zhai, H. M. Christen, L. Zhang, M. Paranthaman

The growth mechanisms of MgB2 films obtained by different methods on various substrates are compared via a detailed cross-sectional scanning electron microscopy (SEM) study. The analyzed films include (a) samples obtained by an ex-situ post-anneal at 900 degree of e-beam evaporated boron in the presence of an Mg vapor (exhibiting bulk-like Tc0 about 38.8 K),

C. Rangan, P. H. Bucksbaum

We employ Optimal Control Theory to discover an efficient information retrieval algorithm that can be performed on a Rydberg atom data register using a shaped terahertz pulse. The register is a Rydberg wave packet with one consituent orbital phase-reversed from the others (the ``marked bit&#39;&#39;). The terahertz pulse that performs the decoding algorithm

P. Torma, I. Jex, W. P. Schleich

We investigate the effect of phase randomness in Ising-type quantum networks. These networks model a large class of physical systems. They describe micro- and nanostructures or arrays of optical elements such as beam splitters (interferometers) or parameteric amplifiers. Most of these stuctures are promising candidates for quantum information processing netw

Yoon-Ho Kim, Maria V. Chekhova, Sergei P. Kulik, Morton H. Rubin

We present theoretical and experimental study of preparing maximally entangled two-photon polarization states, or Bell states, using femtosecond pulse pumped spontaneous parametric down-conversion (SPDC). First, we show how the inherent distinguishability in femtosecond pulse pumped type-II SPDC can be removed by using an interferometric technique without sp

Stefan Scheel, Dirk-Gunnar Welsch

The influence of losses in the interferometric generation and the transmission of continuous-variable entangled light is studied, with special emphasis on Gaussian states. Based on the theory of quantum-state transformation at absorbing dielectric devices, the amount of entanglement is quantified by means of the relative-entropy measure. Upper bounds of enta

V. M. Chabanov, B. N. Zakhariev, I. V. Amirkhanov

The multichannel generalization of the theory of spectral, scattering and decay control is presented. New universal algorithms of construction of complex quantum systems with given properties are suggested. Particularly, transformations of interaction matrices leading to the concentration of waves in a chosen partial channel and spatial localization are show

M. Buttiker

The local Larmor clock is used to derive a hierarchy of local densities of states. At the bottom of this hierarchy are the partial density of states for which represent the contribution to the local density of states if both the incident and outgoing scattering channel are prescribed. On the next higher level is the injectivity which represents the contribut

Le-Man Kuang, Guang-Hong Chen, Yong-Shi Wu

We develop a fully quantum treatment of electromagnetically induced transparency (EIT) in a vapor of three-level $Λ$-type atoms. Both the probe and coupling lasers with arbitrary intensities are quantized, and treated on the same footing. In addition to reproducing known results on ultraslow pulse propagation at the lowest order in the ratio of their Rabi fr

B. Dubetsky, P. R. Berman

The spectrum of the light scattered from an extended atomic wave packet is calculated. For a wave packet consisting of two spatially separated peaks moving on parallel trajectories, the spectrum contains Ramsey-like fringes that are sensitive to the phase difference between the two components of the wave packet. Using this technique, one can establish the mu

Elena Georgieva, Y. S. Kim

There are many two-by-two matrices in layer optics. It is shown that they can be formulated in terms of a three-parameter group whose algebraic property is the same as the group of Lorentz transformations in a space with two space-like and one time-like dimensions, or the $Sp(2)$ group which is a standard theoretical tool in optics. Among the interesting mat

V. Koch, M. Bleicher, S. Jeon

We discuss the physics underlying event-by-event fluctuations in relativistic heavy ion collisions. We will emphasize how the fluctuations of particle ratios can be utilized to explore the properties of the matter created in these collisions. In particular, we will argue that the fluctutions of the ratio of positively over negatively charged particles may se

Jean-Paul Blaizot, Phuong Mai Dinh, Jean-Yves Ollitrault

We discuss the recent NA50 J/Psi production data in Pb--Pb collisions, in particular the second drop at high transverse energies which correspond to the most central collisions. Using a model which relates the J/Psi suppression to the local energy density, we show that the data can be explained by taking into account transverse energy fluctuations at a given

Ye. S. Golubeva, L. A. Kondratyuk, M. Buescher, W. Cassing

The omega-resonance production and its pi0 gamma decay in p-A reactions close to threshold is considered within the Intranuclear Cascade (INC) Model. The pi0 gamma invariant mass distribution shows two components which correspond to the omega decay &#39;inside&#39; and &#39;outside&#39; the nucleus, respectively. The &#39;inside&#39; component is distorted b

Marco Traini

I report on the research activities performed under the (italian) MURST-PRIN project &#34;Fisica Teorica del Nucleo e dei sistemi a piú corpi&#34; covering part of the topics on hadronic degrees of freedom. The most recent achievements in the field are summarized focusing on the specific role of the nuclear physics community.

Burt Holzman

The systematics of baryon stopping and strange particle production have been studied in Au+Au collisions at 6, 8, and 10.8 GeV per nucleon with AGS experiment E917. In particular, the systematic behavior of the proton yields, phi meson production, and the yields of antilambdas and antiprotons are examined as functions of beam energy and centrality.

S. Thummerer, W. von Oertzen, B. Gebauer, S. M. Lenzi

Using particle-$γ$ coincidences we have studied the population of final states after the emission of 2 $α$-particles and of $^{8}$Be in nuclei formed in $^{32}$S+$^{24}$Mg reactions at an energy of $\textrm{E}_{\rm L}(^{32}\textrm{S}) = 130 {\rm MeV}$. The data were obtained in a setup consisting of the GASP $γ$-ray detection array and the multidetector arra

C. Chandre

We analyze by a renormalization method, the dynamics of a particle in a infinite square-well potential driven by an external monochromatic field. This method set up for Hamiltonian systems with two degrees of freedom allows us to analyze precisely the stability of the trajectories of the particle as a function of the amplitude $ε$ of the external field. We c

R. Benzi, L. Biferale, F. Toschi

Universality of statistical properties of passive quantities advected by turbulent velocity fields at changing the passive forcing mechanism is discussed. In particular, we concentrate on the statistical properties of an hydrodynamic system with pressure. We present theoretical arguments and preliminary numerical results which show that the fluxes of passive

H. F. Chau, H. Xu, K. M. Lee, L. W. Siu

Given a continuous function $f(x)$, suppose that the sign of $f$ only has finitely many discontinuous points in the interval $[0,1]$. We show how to use a sequence of one dimensional deterministic binary cellular automata to determine the sign of $f(ρ)$ where $ρ$ is the (number) density of 1s in an arbitrarily given bit string of finite length provided that

J. Froehlich, M. Griesemer, B. Schlein

It is expected that the state of an atom or molecule, initially put into an excited state with an energy below the ionization threshold, relaxes to a groundstate by spontaneous emission of photons which propagate to spatial infinity. In this paper, this picture is established for a large class of models of non-relativistic atoms and molecules coupled to the

Bernhard Baumgartner

Consider a state of a system with several subsystems. The entropies of the reduced state on different subsystems obey certain inequalities, provided there is an equivalence relation, and a function measuring volumes or weights of subsystems. The entropy per unit volume or unit weight, the mean entropy, is then decreasing with respect to an order relation of

Didier Felbacq

We present a possible way of computing resonance poles and modes in scattering theory. Numerical examples are given for the scattering of electromagnetic waves by finite-size photonic crystals.

A. V. Solov&#39;yov, Yu. S. Vladimirov

New mathematical objects called Finslerian N-spinors are discussed. The Finslerian N-spinor algebra is developed. It is found that Finslerian N-spinors are associated with an N^2-dimensional flat Finslerian space. A generalization of the epimorphism SL(2,C) --> O^\uparrow_+(1,3) to a case of the group SL(N,C) is constructed. Particular examples of Finslerian

K. Chadan, R. Kobayashi, T. Kobayashi

The variable phase approach to potential scattering with regular spherically symmetric potentials satisfying (\ref{1e}), and studied by Calogero in his book$^{5}$, is revisited, and we show directly that it gives the absolute definition of the phase-shifts, i.e. the one which defines $δ_{\ell}(k)$ as a continuous function of $k$ for all $k \geq 0$, up to inf

Richard P. Stanley

This paper concerns a probability distribution on the symmetric group generalizing the riffle shuffle of Bayer, Diaconis, and others. There are close connections with the theory of quasisymmetric and symmetric functions.

Won K. Park

We study on the biholomorphic equivalence of a strongly pseudoconvex bounded domain with differentiable spherical boundary to an open ball, and we study on the biholomorphicity of a proper holomorphic self mapping of a strongly pseudoconvex domain with real analytic boundary.

Kiran S. Kedlaya

We exhibit, for n at least 5, infinitely many quadratic number fields admitting unramified degree n extensions with prescribed signature whose normal closures have Galois group A_n. This generalizes a result of Uchida and Yamamoto, which did not include the ability to restrict the signature, and a result of Yamamura, which was the case n=5.

George Lusztig

We describe those unipotent representations of a finite group of Lie type which are defined over the rational numbers.

Timothy Y. Chow

In Chapter 2 we study the path-cycle symmetric function of a digraph, a symmetric function generalization of Chung and Graham&#39;s cover polynomial. Most of this material appears in either Advances in Math. 118 (1996), 71-98 or J. Algebraic Combin. 10 (1999), 227-240. Chapter 3 contains miscellaneous results about Stanley&#39;s symmetric function generaliza

Y. Markov, A. Varchenko

The trigonometric KZ equations associated to a Lie algebra \g depend on a parameter λin \h where \h is a Cartan subalgebra of \g. A system of dynamical difference equations with respect to λcompatible with the KZ equations is introduced in Tarasov and Varchenko. We prove that the standard hypergeometric solutions of the trigonometric KZ equations associated

Markus Wessler

We give a proof of Iitaka&#39;s Conjecture C_{2,1} using only elementary methods from algebraic geometry. The main point is that, given a non-isotrivial and relatively minimal family f : X \to B, where X is a surface and B is a curve, both smooth and projective, we show that the direct image of the relatively canonical sheaf has strictly positive degree.

Gianni Dal Maso, Rodica Toader

We give a precise mathematical formulation of a variational model for the irreversible quasi-static evolution of brittle fractures proposed by G.A. Francfort and J.-J. Marigo, and based on Griffith&#39;s theory of crack growth. In the two-dimensional case we prove an existence result for the quasi-static evolution and show that the total energy is an absolut

Stefan Haller, Josef Teichmann, Cornelia Vizman

We determine the Riemannian manifolds for which the group of exact volume preserving diffeomorphisms is a totally geodesic subgroup of the group of volume preserving diffeomorphisms, considering right invariant $L^2$-metrics. The same is done for the subgroup of Hamiltonian diffeomorphisms as a subgroup of the group of symplectic diffeomorphisms in the Kähle

Joachim Cuntz

We associate a non-commutative $C^*$-algebra with any locally finite simplicial complex. We determine the $K$-theory of these algebras and show that they can be used to obtain a conceptual explanation for the Baum-Connes conjecture.

Vitaly Vologodsky

We provide an easy characterization for the locus of indeterminacy of the Prym map in terms of the dual graphs of stable curves. As a corollary, we show that the closure of the Fridman-Smith locus coincides with the locus of indeterminacy of the Prym map.

J. Maurice Rojas

Suppose L is any finite algebraic extension of either the ordinary rational numbers or the p-adic rational numbers. Also let g_1,...,g_k be polynomials in n variables, with coefficients in L, such that the total number of monomial terms appearing in at least one g_i is exactly m. We prove that the maximum number of isolated roots of G:=(g_1,...,g_k) in L^n i

Ioannis Giannakis, Hai-cang Ren

We solve the Einstein equations in the Randall-Sundrum framework using an isotropic ansatz for the metric and obtain an exact expression to first order in the gravitational coupling. The solution is free from metric singularities away from the source and it satisfies the Israel matching condition on a straight brane. At distances far away from the source and

Sang-Ok Hahn, Youngjai Kiem, Yoonbai Kim, Phillial Oh

In the warped compactification with a single Randall-Sundrum brane, a puzzling claim has been made that scalar fields can be bound to the brane but their Hodge dual higher-rank anti-symmetric tensors cannot. By explicitly requiring the Hodge duality, a prescription to resolve this puzzle was recently proposed by Duff and Liu. In this note, we implement the H

M. Caselle, P. Grinza, N. Magnoli

We investigate the presence of irrelevant operators in the 2d Ising model perturbed by a magnetic field, by studying the corrections induced by these operators in the spin-spin correlator of the model. To this end we perform a set of high precision simulations for the correlator both along the axes and along the diagonal of the lattice. By comparing the nume

M. P. Garcia del Moral, A. Restuccia

A regularized model of the double compactified D=11 supermembrane with nontrivial winding in terms of SU(N) valued maps is obtained. The condition of nontrivial winding is described in terms of a nontrivial line bundle introduced in the formulation of the compactified supermembrane. The multivalued geometrical objects of the model related to the nontrivial w

Ichiro Oda

We show that as in abelian gauge fields, nonabelian gauge fields are also trapped on a brane in the Randall-Sundrum model by applying a new mechanism based on topological Higgs mechanism. It is pointed out that although almost massless gauge fields are localized on the brane by the new mechanism, exactly massless gauge fields are not localized. This fact doe

James. D. Bjorken

Simple functional relations amongst standard model couplings, including gravitional, are conjectured. Possible implications for cosmology and future theory are discussed.

H. Haberzettl

It is shown that comments by Guichon [hep-ph/0012126], and also by Bernard, Kaiser, and Meißner [hep-ph/0101062], regarding my recent criticism [Phys. Rev. Lett. 85, 3576 (2000)] of how the axial form factor is supposed to enter pion electroproduction do not address the main point of my argument and therefore are irrelevant.

David Atwood

Direct CP violation in decays such as B- -> D0 K- is sensitive to the CKM angle phi_3 because these decays allow the interference of b-quark to c-quark with b-quark to u-quark transitions. Indeed, phi_3 may be determined if one can infer the strong phase of the B and subsequent D0 decays from experimental data. In this talk, I will discuss how this can be ca

Maria Krawczyk, Andrzej Zembrzuski

We present NLO QCD predictions for the prompt photon photoproduction at the THERA, and compare them with results for the HERA collider.