February 2000 arXiv papers — page 16

N. G. Deshpande

Constraints on angles of Unitarity triangle are reviewed, and in particular constraint on $γ$ from limit on $Δm_s$ is emphasized. Effects of penguin diagram on measurement of $β$ and $α$ are then reviewed. New measurements on $B \to π^+π^-$ in QCD improved factorization approximation suggest large penguin effects. It is possible to estimate the error in meas

Vigdor L. Teplitz, Rabindra N. Mohapatra, Fred Olness, Ryszard Stroynowski

We consider laboratory experiments that can detect stable, neutral strongly interacting massive particles (SIMPs). We explore the SIMP annihilation cross section from its minimum value (restricted by cosmological bounds) to the barn range, and vary the mass values from a GeV to a TeV. We also consider the prospects and problems of detecting such particles at

John Ellis

After recalling briefly the main physics issues beyond the Standard Model, the main physics objectives of experiments at CERN in the coming decade(s) are reviewed. These include the conclusion of the LEP programme during the year 2000, a limited number of fixed-target experiments during the following years, the CNGS long-baseline neutrino programme and the L

F. Cano, P. Faccioli, S. Scopetta, M. Traini

We study the quark angular momentum distribution in the nucleon within a light-front covariant quark model. Special emphasis is put into the orbital angular momentum: a quantity which is very sensitive to the relativistic treatment of the spin in a light-front dynamical approach. Discrepancies with the predictions of the low-energy traditional quark models w

Stefano Frixione, Michael Krämer, Eric Laenen

We review the production of charm and bottom quarks in two-photon collisions at e+e- colliders. The next-to-leading order QCD predictions for total cross sections and differential distributions are compared with recent experimental results.

Ramon Miquel

The capabilities of future CP violation experiments in hadron machines are reviewed. Special emphasis is put on the CDF experiment in the run II of the Tevatron, due to start taking data in 2001, and on LHCb and BTeV, on a longer time scale.

R. F. Wagenbrunn, M. Radici, S. Boffi, P. Demetriou

We present results for the nucleon magnetic moments in the context of an extended chiral constituent quark model based on the mechanism of the Goldstone boson exchange, as suggested by the spontaneous breaking of chiral symmetry in QCD. The electromagnetic charge-current operator is consistently deduced from the model Hamiltonian, which includes all force co

M. Yoshimura

A new theoretical framework for computation of the relic abundance of cold dark matter particles such as LSP is presented and some generic features of new results are discussed. The most important is a generalization of the Boltzmann equation to include off-shell effects and its thermal average over cosmic medium. It is shown that at very low temperatures, m

V. G. Baryshevsky, D. N. Matsukevich

The rotation of polarization plane of light in a gas placed in the electric field is considered. Different mechanisms that cause this phenomenon are investigated. Angle of polarization plane rotation for transition 6S_{1/2} -> 7S_{1/2} in cesium is estimated. The possibility to observe this effect in experiment is discussed.

Jaume Guasch, Wolfgang Hollik, Joan Sola

We review the one-loop corrections to the partial decay width of sbottom-quark into a top quark and a chargino for the parameter space relevant to the TESLA e+e- linear collider. We present the results available in the literature for the QCD and the Yukawa coupling corrections in a unified framework. In this way a direct comparison of the size of the various

Adrian Patrascioiu

The behaviour of the renormalized spin 2-point function in the O(3) and dodecahedron spin model are investigated numerically. The Monte Carlo data show excellent agreement between the two models. The short distance behavior comes very close to standard theoretical expectations, yet it differs significantly from it. A possible explanation of this situation is

K. Yamagishi, S. Kitahara, T. Suzuki

We obtain an almost perfect monopole action numerically after abelian projection in pure SU(3) lattice QCD. Performing block-spin transformations on the dual lattice, the action fixed depends only on a physical scale b. Monopole condensation occurs for large b region. The numerical results show that two-point monopole interactions are dominant for large b. W

Sergio Bertolucci

The major goal of the KLOE experiment is to measure Re(epsilon' /epsilon) in the kkbar system, with a precision of 10^{-4},both via the traditional double ratio method and quantum interferometry. The experiment has started taking data at DAFNE, the phi-factory built at the Frascati National Laboratory (LNF) of INFN in Italy, beginning in April 1999. In t

P. Astone, G. Pizzella

We compare the ``unified approach'' for the estimation of upper limits with an approach based on the Bayes theory, in the special case that no events are observed. The ``unified approach'' predicts, in this case, an upper limit that decreases with the increase in the expected level of background. This seems absurd. On the other hand, the Baye

A. I. Nikishov

Weinberg's energy-momentum pseudotensor is obtained for Schwarzschild metric in harmonic coordinates. On the horizon it possesses unintegrable singularities. For this reason the total energy of a collapsar can't be obtained by integrating energy density over the system's volume. The implication for gravity theories is noted. A thought on how to c

Dirk K. Morr, Jörg Schmalian, David Pines

In this communication we consider the doping dependence of the strong antiferromagnetic spin fluctuations in the cuprate superconductors. We investigate the effect of an incommensurate magnetic response, as recently observed in inelastic neutron scattering (INS) experiments on several YBa_2Cu_3O_{6+x} compounds, on the spin-lattice and spin-echo relaxation r

F. A. B. F. de Moura, U. Tirnakli, M. L. Lyra

For a family of logistic-like maps, we investigate the rate of convergence to the critical attractor when an ensemble of initial conditions is uniformly spread over the entire phase space. We found that the phase space volume occupied by the ensemble W(t) depicts a power-law decay with log-periodic oscillations reflecting the multifractal character of the cr

Ulrich Bilstein

We compute the continuum limit of the spectra for the XX-model with arbitrary complex boundary fields. In the case of hermitian boundary terms one obtains the partition functions of the free compactified boson field on a cylinder with Neumann-Neumann, Dirichlet-Neumann or Dirichlet-Dirichlet boundary conditions. This applies also for certain non-hermitian bo

F. F. Haas, F. Schmid, K. Binder

We present Monte Carlo simulations of surface induced disordering in a model of a binary alloy on a bcc lattice which undergoes a first order bulk transition from the ordered DO3 phase to the disordered A2 phase. The data are analyzed in terms of an effective interface Hamiltonian for a system with several order parameters in the framework of the linear reno

Sumiyoshi Abe, and A. K. Rajagopal

Starting from microcanonical basis with the principle of equal a priori probability, it is found that, besides ordinary Boltzmann-Gibbs theory with the exponential distribution, a theory describing systems with power-law distributions can also be derived.

C. H. Choo, H. P. Schriemer, D. R. Taylor

Using birefringence techniques we have measured the critical exponents beta, gamma, and delta in As-doped TbVO4, a structural realization of the random-field Ising model where random strain fields are introduced by V-As size mismatch. For pure TbVO4 we observe the expected classical critical exponents, while for a mixed sample with 15% As concentration our r

F. F. Haas, F. Schmid, K. Binder

We present recent Monte Carlo results on surfaces of bcc-structured binary alloys which undergo an order-disorder phase transformation in the bulk. In particular, we discuss surface order and surface induced disorder at the bulk transition between the ordered (DO3) phase and the disordered (A2) phase. An intricate interplay between different ordering and seg

Misha Turlakov

The Johnson-Nyquist noise in narrow wires having a transverse size smaller than the screening length is shown to be white up to the frequency $D/L^2$ and to decay at higher frequencies as $ω^{-{1/2}}$. In two-dimensional films having a thickness smaller than the screening length, the Johnson-Nyquist noise is predicted to be frequency independent up to the fr

F. S. Bergeret, K. B. Efetov, A. I. Larkin

We study a possibility of a non-homogeneous magnetic order (cryptoferromagnetic state) in heterostructures consisting of a bulk superconductor and a ferromagnetic thin layer that can be due to the influence of the superconductor. The exchange field in the ferromagnet may be strong and exceed the inverse mean free time. A new approach based on solving the Eil

Gauri R. Pradhan, Sagar A. Pandit, Anil D. Gangal, V. Sitaramam

Numerical simulations on a 2-dimensional model system showed that voids are induced primarily due to shape anisotropy in binary mixtures of interacting disks. The results of such a simple model account for the key features seen in a variety of flux experiments using liposomes and biological membranes.

M. Cerruti-Sola, C. Clementi, M. Pettini

The Hamiltonian dynamics associated to classical, planar, Heisenberg XY models is investigated for two- and three-dimensional lattices. Besides the conventional signatures of phase transitions, here obtained through time averages of thermodynamical observables in place of ensemble averages, qualitatively new information is derived from the temperature depend

Z. Toroczkai, G. Korniss, S. Das Sarma, R. K. P. Zia

We introduce and investigate the stochastic dynamics of the density of local extrema (minima and maxima) of non-equilibrium surface fluctuations. We give a number of exact, analytic results for interface fluctuations described by linear Langevin equations, and for on-lattice, solid-on-solid surface growth models. We show that in spite of the non-universal ch

Martin P. Gelfand, Mohan Mahadevan

Calculations of nuclear spin-lattice relaxation rates are carried out by means of exact diagonalization on small (2 x 6) antiferromagnetic Heisenberg ladders, using the simplest forms permitted by symmetry for the hyperfine couplings for the three nuclear sites in Cu2O3 ladders. Several values of the rung/chain exchange ratio have been considered. Comparison

N. Kameswara Rao, David L. Lambert

High-resolution optical spectra of the R Coronae Borealis (RBC) star V854 Centauri in the early stages of a decline show, in addition to the features reported for other RCBs in decline, narrow absorption lines from the C_2 Phillips system. The low rotational temperature, T_rot = 1150K, of the C_2 ground electronic state suggests the cold gas is associated wi

M. R. Burleigh, U. Heber, D. O'Donoghue, M. A. Barstow

We have re-observed and re-analysed the optical spectrum of the Schweizer-Middleditch star, a hot subdwarf which lies along almost the same line-of-sight as the centre of the historic SN1006 supernova remnant (SNR). Although this object is itself unlikely to be the remnant of the star which exploded in 1006AD, Wellstein et al. (1999) have demonstrated that i

Laurent Eyer, Michel Grenon

Among the 17 volumes of results from the Hipparcos space mission, two are dedicated to variable stars. These two volumes arose from the work of two groups, one at the Geneva Observatory and one at RGO (Royal Greenwich Observatory), on the 13 million photometric measurements produced by the satellite for 118204 stars. The analysis of photometric time series p

L. Dunne, S. A. Eales, M. G. Edmunds, R. J. Ivison

We have used SCUBA to observe a complete sample of 104 galaxies selected at 60 microns from the IRAS BGS and we present here the 850 micron measurements. Fitting the 60,100 and 850 micron fluxes with a single temperature dust model gives the sample mean temperature T=36 K and beta = 1.3. We do not rule out the possibility of dust which is colder than this, i

Philip Massey, Elizabeth Waterhouse, Kathleen DeGioia-Eastwood

We combine new CCD UBV photometry and spectroscopy with that from the literature to investigate 19 Magellanic Cloud OB associations that contain Wolf-Rayet (WR) and other types of evolved massive stars. Our spectroscopy reveals a wealth of newly identified interesting objects, including early O-type supergiants, a high mass double-lined binary in the SMC, an

J. M. Lattimer, M. Prakash

The structure of neutron stars is considered from theoretical and observational perspectives. We demonstrate an important aspect of neutron star structure: the neutron star radius is primarily determined by the behavior of the pressure of matter in the vicinity of nuclear matter equilibrium density. In the event that extreme softening does not occur at these

Sultana N. Nahar, Franck Delahaye, Anil K. Pradhan, C. J. Zeippen

An extensive set of dipole-allowed, intercombination, and forbidden transition probabilities for Fe V is presented. The Breit-Pauli R-matrix (BPRM) method is used to calculate 1.46 x 10^6 oscillator strengths for the allowed and intercombination E1 transitions among 3,865 fine-structure levels dominated by configuration complexes with n <= 10 and l <= 9. The

D. Dal Fiume, L. Amati, L. A. Antonelli, F. Fiore

We report the X/gamma-ray spectrum of GRB971214 and of its afterglow. The afterglow was measured few hours after the main event and for an elapsed time of more than two days. The measure of this GRB and afterglow is relevant due to its extreme, cosmological distance (z=3.42). The prompt event shows a hard photon spectrum, consistent with a broken power law w

D. W. Koerner, E. L. N. Jensen, K. L. Cruz, T. B. Guild

We present sub-arcsecond thermal infrared imaging of HD 98800, a young quadruple system composed of a pair of low-mass spectroscopic binaries separated by 0.8&#39;&#39; (38 AU), each with a K-dwarf primary. Images at wavelengths ranging from 5 to 24.5 microns show unequivocally that the optically fainter binary, HD 98800B, is the sole source of a comparative

K. O&#39;Neil

Recent surveys have discovered hundreds of low surface brightness galaxies, systems with central surface brightness fainter than 22.0 B mag arcsec^-2, in the local universe. Plots of the surface brightness distribution - that is, the space density of galaxies plotted against central surface brightness - show a flat space density distribution from the canonic

G. Setti, G. Brunetti, A. Comastri

We review the evidence that detectable fluxes of X-rays are produced by inverse Compton scattering of nuclear photons with the relativistic electrons in the radio lobes of strong FRII radio galaxies within the FRII-RL quasar unification scheme. We report here on the possible detection of this effect in two steep spectrum RL quasars. This may have important i

S. Colafrancesco, C. R. Mullis, A. Wolter, I. M. Gioia

We report the first detailed X-ray and optical observations of the medium-distant cluster A33 obtained with the Beppo-SAX satellite and with the UH 2.2m and Keck II telescopes at Mauna Kea. The information deduced from X-ray and optical imaging and spectroscopic data allowed us to identify the X-ray source 1SAXJ0027.2-1930 as the X-ray counterpart of the A33

M. Ruiz, D. M. Alexander, S. Young, J. Hough

We present near-infrared broad-band polarization images of the nuclear regions of the Circinus galaxy in the J, H and K bands. For the first time the south-eastern reflection cone is detected in polarized light, which is obscured at optical wavelengths behind the galactic disk. This biconical structure is clearly observed in J and H band polarized flux whils

A. Boccaletti, P. Riaud, C. Moutou, A. Labeyrie

Diluted arrays of many optical apertures will be able to provide h igh-resolution snapshot images if the beams are combined according to the densified-pupil scheme. We show that the same principle can also provide coronagraphic images, for detecting faint sources near a bright unresolved one. Recent refinements of coronagraphic techniques, i.e. the use of a

Kyril P. Panov, Martin Altmann, Wilhelm Seggewiss

In 1991, a long term UBV-photometry campaign of four Wolf-Rayet stars was started using the 60 cm telescope of the National Astronomical Observatory Rozhen, Bulgaria. Here we report on our observational results and discuss the light variations. The star WR 137 showed only random light variations, which are probably due to dynamical wind instabilities but not

B. Paul, M. Kawasaki, T. Dotani, F. Nagase

We present new observations of two anomalous X-ray pulsars (AXP) 4U 0142+61 and 1E 1048.1-5937 made in 1998 with the ASCA. The energy spectra of these two AXPs are found to consist of two components, a power-law and a blackbody emission from the neutron star surface. These observations, when compared to earlier ASCA observations in 1994 show remarkable stabi

B. Paul, S. Kitamoto, F. Makino

We report the detection of changes in the long-term intensity variations in two X-ray binaries, Cyg X-2 and LMC X-3. In this work, we have used the long-term light curves obtained with the All-Sky Monitors (ASMs) of the Rossi X-Ray Timing Explorer (RXTE), Ginga, Ariel 5, and Vela 5B and the scanning modulation collimator of HEAO 1. It is found that in the li

Andrew Lee, Elliott D. Bloom, Vahe Petrosian

The time profiles of many gamma-ray bursts consist of distinct pulses, which offers the possibility of characterizing the temporal structure of these bursts using a relatively small set of pulse shape parameters. We have used a pulse decomposition procedure to analyze the Time-to-Spill (TTS) data for all bursts observed by BATSE up through trigger number 200

Andrew Lee, Elliott D. Bloom, Vahe Petrosian

The time profiles of many gamma-ray bursts consist of distinct pulses, which offers the possibility of characterizing the temporal structure of these bursts using a relatively small set of pulse shape parameters. This pulse decomposition analysis has previously been performed on a small sample of bright long bursts using binned data from BATSE, which comes i

Pavel Kroupa

The stellar-dynamical evolution of bound star clusters during the first few Myr is dominated by binary-binary and binary-star interactions, the rapid sinking of the most massive stars to the centre of the clusters and mass loss from evolving stars. The consequences of these processes for the binary and stellar population in clusters, and for the star cluster

T. Ohgaki

We study a method of laser-Compton cooling of electron beams. Using a Monte Carlo code, we evaluate the effects of the laser-electron interaction for transverse cooling. The optics with and without chromatic correction for the cooling are examined. The laser-Compton cooling for JLC/NLC at E_0=2 GeV is considered.

Alec Matusis, Leonard Susskind, Nicolaos Toumbas

Quantum field theory on non-commutative spaces does not enjoy the usual ultraviolet-infrared decoupling that forms the basis for conventional renormalization. The high momentum contributions to loop integrations can lead to unfamiliar long distance behavior which can potentially undermine naive expectations for the IR behavior of the theory. These &#34;anoma

M. Veselsky, R. W. Ibbotson, R. Laforest, E. Ramakrishnan

Multifragmentation of quasiprojectiles was studied in reactions of 28Si beam with 112Sn and 124Sn targets at projectile energies 30 and 50 MeV/nucleon. The quasiprojectile observables were reconstructed using isotopically identified charged particles with Z_f <= 5 detected at forward angles. The nucleon exchange between projectile and target was investigated

L. You, M. S. Chapman

We propose an implementation for quantum logic and computing using trapped atomic spins of two different species, interacting via direct magnetic spin-spin interaction. In this scheme, the spins (electronic or nuclear) of distantly spaced trapped neutral atoms serve as the qubit arrays for quantum information processing and storage, and the controlled intera

A. Mourachkine

Andreev-reflection and tunneling studies have been carried out on a single crystal of underdoped Nd1.85Ce0.15CuO4-d (NCCO) by using Ag, Pt-Ir and Nb tips to clarify the symmetry of its order parameter. Surprisingly, we observed in the NCCO, on the one hand, the Josephson current (with Nb tip) which indicates the presence of s-wave order parameter, on the oth

Ruth Gregory, Valery A. Rubakov, Sergei M. Sibiryakov

The standard picture of viable higher-dimensional theories is that extra dimensions manifest themselves at short distances only, their effects being negligible at scales larger than some critical value. We show that this is not necessarily true in models with infinite extra dimensions. As an example, we consider a five-dimensional scenario with three 3-brane

A. Feinstein, K. E. Kunze, M. A. Vazquez-Mozo

We propose a picture, within the pre-big-bang approach, in which the universe emerges from a bath of plane gravitational and dilatonic waves. The waves interact gravitationally breaking the exact plane symmetry and lead generically to gravitational collapse resulting in a singularity with the Kasner-like structure. The analytic relations between the Kasner e

Matteo Palassini, A. P. Young

The nature of the spin glass state is investigated by studying changes to the ground state when a weak perturbation is applied to the bulk of the system. We consider short range models in three and four dimensions and the infinite range Sherrington-Kirkpatrick (SK) and Viana-Bray models. Our results for the SK and Viana-Bray models agree with the replica sym

Michal Fabinger, Petr Horava

We study a non-supersymmetric $E_8\times\bar E_8$ compactification of M-theory on $S^1/Z_2$, related to the supersymmetric $E_8\times E_8$ theory by a chirality flip at one of the boundaries. This system represents an M-theory analog of the D-brane anti-D-brane systems of string theory. Alternatively, this compactification can be viewed as a model of supersy

M. Jamet, V. Dupuis, P. Melinon, A. Perez

Our recent studies on Co-clusters embedded in various matrices reveal that the co-deposition technique (simultaneous deposition of two beams : one for the pre-formed clusters and one for the matrix atoms) is a powerful tool to prepare magnetic nanostructures with any couple of materials even though they are miscible. We study, both sharply related, structure

S. B. Kraemer, I. M. George, T. J. Turner, D. M. Crenshaw

There are several Seyfert galaxies for which there is a discrepancy between the small column of neutral hydrogen deduced from X-ray observations and the much greater column derived from the reddening of the optical/UV emission lines and continuum. The standard paradigm has the dust within the highly ionized gas which produces O~VII and O~VIII absorption edge

S. E. Perez Bergliaffa, K. E. Hibberd

We investigate the propagation of electromagnetic waves through a static wormhole. It is shown that the problem can be reduced to a one-dimensional Schrödinger-like equation with a barrier-type potential. Using numerical methods, we calculate the transmission coefficient as a function of the energy. We also discuss the polarization of the outgoing radiation

J. V. Alvarez, Claudius Gros

We present an efficient way to compute diagonal and off-diagonal n-point correlation functions for quantum spin-systems within the loop algorithm. We show that the general rules for the evaluation of these correlation functions take an especially simple form within the framework of directed loops. These rules state that contributing loops have to close coher

Anders Sorensen, Klaus Molmer

With bichromatic fields it is possible to deterministically produce entangled states of trapped ions. In this paper we present a unified analysis of this process for both weak and strong fields, for slow and fast gates. Simple expressions for the fidelity of creating maximally entangled states of two or an arbitrary number of ions under non-ideal conditions

Hiroshi Suzuki

We study the gauge anomaly ${\cal A}$ defined on a 4-dimensional infinite lattice while keeping the lattice spacing finite. We assume that (I) ${\cal A}$ depends smoothly and locally on the gauge potential, (II) ${\cal A}$ reproduces the gauge anomaly in the continuum theory in the classical continuum limit, and (III) U(1) gauge anomalies have a topological

Masako Bando, Tatsuo Kobayashi, Tatsuya Noguchi, Koichi Yoshioka

We discuss the existence of hierarchy of Yukawa couplings in the models with extra spatial dimensions. The hierarchical structure is induced by the power behavior of the cutoff dependence of the evolution equations which yield large suppressions of couplings at the compactification scale. The values of coupling constants at this scale can be made stable almo

Stefano Bellucci, Anton Galajinsky

On an explicit example of the Siegel superparticle we study an alternative to the harmonic superspace approach. The latter seems to be the only method for quantizing infinitely reducible first class constraints currently available. In an appropriately extended phase space, the infinite ghost tower is effectively canceled by that coming from the sector of aux

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

We extend to the special case of Bhabha scattering the &#34;Z-peak subtracted&#34; representation previously applied to e+e- to f f(bar) (f different from e). This allows us to analyze the process at any energy while imposing in an automatic way the constraints set by high precision measurements at the Z peak. The procedure turns out to be particularly conve

H. Kachkachi, D. A. Garanin

We derive a free energy for weakly anisotropic ferromagnets which is valid in the whole temperature range and interpolates between the micromagnetic energy at zero temperature and the Landau free energy near the Curie point T_c. This free energy takes into account the change of the magnetization length due to thermal effects, in particular, in the inhomogene

W. J. Percival, L. Miller, R. J. McLure, J. S. Dunlop

We present the results of a deep K-band imaging study which reveals the host galaxies around a sample of luminous radio-quiet quasars. The K-band images, obtained at UKIRT, are of sufficient quality to allow accurate modelling of the underlying host galaxy. Initially, the basic structure of the hosts is revealed using a modified Clean deconvolution routine o

Toshihiko Hattori, Tsutom Hasuike, Seiichi Wakaizumi

We investigate CP-violation effect in the long-baseline neutrino oscillation in the four-neutrino model with mass scheme of the two nearly degenerate pairs separated with the order of 1 eV, by using the data from the solar neutrino deficit, the atmospheric neutrino anomaly and the LSND experiments along with the other accelerator and reactor experiments. By

Kazuo Hosomichi

We study the eleven-dimensional supergravity and the classical solutions corresponding to M2-branes ending on M5-branes. We obtain the generic BPS configuration representing two sets of parallel M5-branes with (1+1) commonly longitudinal directions and M2-branes stretching between them. We also discuss how the brane creation is described in supergravity.

Philip R. Page, Terry Goldman, Joseph. N. Ginocchio

Experimental data indicate small spin-orbit splittings in hadrons. For heavy-light mesons we identify a relativistic symmetry that suppresses these splittings. We suggest an experimental test in electron-positron annihilation. Furthermore, we argue that the dynamics necessary for this symmetry are possible in QCD.

Zoltan Haiman, Lam Hui

The lifetime t_Q of the luminous phase of quasars is constrained by current observations to be between 10^6 and 10^8 years, but is otherwise unkown. We model the quasar luminosity function in detail in the optical and X-ray bands using the Press-Schechter formalism, and show that the expected clustering of quasars depends strongly on their assumed lifetime.

W. Dür, J. I. Cirac

We analyze the existence of activable bound entangled states in multi-particle systems. We first give a series of examples which illustrate some different ways in which bound entangled states can be activated by letting some of the parties to share maximally entangled states. Then, we derive necessary conditions for a state to be distillable as well as to be

Andrei N. Soklakov, Ruediger Schack

Consider a joint quantum state of a system and its environment. A measurement on the environment induces a decomposition of the system state. Using algorithmic information theory, we define the preparation information of a pure or mixed state in a given decomposition. We then define an optimal decomposition as a decomposition for which the average preparatio

Oliver Rudolph

We give a necessary and sufficient condition for a mixed quantum mechanical state to be separable. The criterion is formulated as a boundedness condition in terms of the greatest cross norm on the tensor product of trace class operators.

M. Genovese, G. Brida, C. Novero, E. Predazzi

We report on the realisation of a new test of Bell inequalities using the superposition of type I parametric down conversion produced in two different non-linear crystals pumped by the same laser, but with different polarisation. The produced state is non-maximally entangled. We discuss the advantages and the possible developments of this configuration.

M. Rodriguez, K. -A. Suominen, B. M. Garraway

We propose a method for achieving highly efficient transfer between the vibrational states in a diatomic molecule. The process is mediated by strong laser pulses and can be understood in terms of light-induced potentials. In addition to describing a specific molecular system, our results show how, in general, one can manipulate the populations of the differe

Carlos Castro, Alex Granik

Recently a New Relativity Principle has been proposed by one of the authors as the underlying physical and geometrical foundations of String and {\bf M} Theory. It is explicitly shown that within the framework of the New Relativity Theory, some Quantum Mechanical Paradoxes like the Einstein-Rosen Podolsky and the Black Hole Information Loss, are easily resol

Kensuke Yokoi, Feng Xiao

We investigated numerically the relation between a roller and the pressure distribution to clarify the dynamics of the roller in circular hydraulic jumps. We found that a roller which characterizes a type II jump is associated with two high pressure regions after the jump, while a type I jump (without the roller) is associated with only one high pressure reg

E. Lomon

Elastic ed scattering, with deuteron polarization, up to high momentum transfer provides detailed information on the deuteron wave function. This determines the range dependence of the orbital and spin components of the one- and two-body currents, restricting contributions of isobar and meson-exchange currents and of quark/gluon degrees of freedom, as well a

C. Hanhart, J. Haidenbauer, O. Krehl, J. Speth

First calculations for spin-dependent observables of the reactions $pp \to ppπ^0$, $pp \to pnπ^+$ and $pp \to dπ^+$ near threshold are presented, employing the Jülich model for pion production. The influence of resonant (via the excitation of the $Δ(1232)$) and non-resonant p-wave pion production mechanisms on these observables is examined. For the reactions

J. B. Elliott, the EOS Collaboration

The cluster distributions of different systems are examined to search for signatures of a continuous phase transition. In a system known to possess such a phase transition, both sensitive and insensitive signatures are present; while in systems known not to possess such a phase transition, only insensitive signatures are present. It is shown that nuclear mul

Stephanie Rossano, Christian Brouder

An explicit perturbative solution to all orders is given for a general class of nonlinear differential equations. This solution is written as a sum indexed by rooted trees and uses the Green function of a linearization of the equations. The modifications due to the presence of zero-modes is considered. Possible divergence of the integrals can be avoided by u

Andre C. R. Martins

A new evolutionary solution to Prisoner Dilemma situations is proposed in this paper. A specific genetic code may have different phenotypes, meaning different strategies for different individuals carrying that gene. This means that, under the right parameters, it is a good evolutionary solution to create two types of phenotypes with different strategies, her

I. Laba, A. Soffer

We consider the NLS on Schwarzschild manifold.For radial solutions with sufficiently localized initial data,global existence,L^p estimates and asymptotic completeness of the wave operators is proved

A. Patrascioiu

The low temperature regime of nonabelian two-dimensional ferromagnets is investigated. The method involves mapping such models into certain site-bond peroclation processes and using ergodicity in a novel fashion. It is concluded that all ferromagnets possessing a continuous symmetry (abelian or not) exihibit algebraic decay of correlations at sufficiently lo

R. Kenyon

We define a scaling limit of the height function on the domino tiling model (dimer model) on simply-connected regions in Z^2 and show that it is the ``massless free field&#39;&#39;, a Gaussian process with independent coefficients when expanded in the eigenbasis of the Laplacian.

Luca Bombelli, Sebastiano Sonego

One can define several properties of wave equations that correspond to the absence of tails in their solutions, the most common one by far being Huygens&#39; principle. Not all of these definitions are equivalent, although they are sometimes assumed to be. We analyse this issue in detail for linear scalar waves, establishing some relationships between the va

K. Hulek, G. K. Sankaran

This is a survey article about Siegel modular varieties over the complex numbers. It is written mostly from the point of view of moduli of abelian varieties, especially surfaces. We cover compactification of Siegel modular varieties; classification of the compactified varieties by Kodaira dimension, etc.; moduli of abelian surfaces and especially application

Michael Frank

Normal conditional expectations E: M --> N in M of finite index on von Neumann algebras M with discrete center are investigated to find an estimate for the minimal number of generators of M as a Hilbert N-module. Analyzing the case of M being finite type I with discrete center we obtain that these von Neumann algebras M are always finitely generated Hilbert

J. Brian Conrey, Gerald Myerson

The authors modify the Balazard-Saias criterion for the Riemann hypothesis by changing the cutoff of the Dirichlet series. They establish some asymptotic results related to the modified criterion.

I. Laba

We prove that a union of two intervals in R is a spectral set if and only if it tiles R by translations.

Daniel Allcock, Eberhard Freitag

The moduli space of cubic surfaces in complex projective space is known to be isomorphic to the quotient of the complex 4-ball by a certain arithmetic group. We apply Borcherds&#39; techniques to construct automorphic forms for this group and show that these provide an embedding of the moduli space in 9-dimensional projective space. We also show that our aut

Alessandro Ghigi

Given a Kaehler manifold of complex dimension 4, we consider submanifolds of (real) dimension 4, whose Kaehler angles coincide. We call these submanifolds Cayley. We investigate some of their basic properties, and prove that (a) if the ambient manifold is a Calabi-Yau, the minimal Cayley submanifolds are just the Cayley submanifolds as defined by Harvey and

Ofer Gabber, Lorenzo Ramero

The categories of almost modules and almost algebras are introduced as a convenient setting for the development of Faltings&#39; method of almost etale extensions. After some preliminaries of general &#34;almost homological algebra&#34; we construct the almost version of the cotangent complex and we use it to generalise some results of Faltings on the liftin

H. Ahmedov, I. H. Duru

E(2) is studied as the automorphism group of the Heisenberg algebra H. The basis in the Hilbert space K of functions on H on which the unitary irreducible representations of the group are realized is explicitely constructed. The addition theorem for the Kummer functions is derived.

Ilse Fischer, C. H. C. Little

In 1967 Kasteleyn introduced a powerful method for enumerating the 1-factors of planar graphs. In fact his method can be extended to graphs which permit an orientation under which every alternating circuit is clockwise odd. Graphs with this property are called {\it Pfaffian}. Little characterised Pfaffian bipartite graphs in terms of forbidden subgraphs in 1

Martin Snethlage

There are some papers which describe the use of bootstrap techniques in point process statistics. The aim of the present paper is to show that the form in which bootstrap is used there is dubious. In case of variance estimation of pair correlation function estimators the used bootstrap techniques lead to results which can be obtained simpler without simulati

B. Geyer, M. Lazar

For arbitrary spacetime dimension a systematic procedure is carried on to uniquely decompose nonlocal light-cone operators into harmonic operators of well defined twist. Thereby, harmonic tensor polynomials up to rank 2 are introduced. Symmetric tensor operators of rank 2 are considered as an example.

James T. Wheeler

We show that the grading of fields by conformal weight, when built into the initial group symmetry, provides a discrete, non-central conformal extension of any group containing dilatations. We find a faithful vector representation of the extended conformal group and show that it has a scale-invariant scalar product and satisfies a closed commutator algebra.