January 2005 arXiv papers — page 6

Harry Westfahl, Joerg Schmalian

We study the effect of a random Flory-Huggins parameter in a symmetric diblock copolymer melt which is expected to occur in a copolymer where one block is near its structural glass transition. In the clean limit the microphase segregation between the two blocks causes a weak, fluctuation induced first order transition to a lamellar state. Using a renormaliza

Lorenzo Bertini, Davide Gabrielli, Joel L. Lebowitz

We investigate a one dimensional chain of $2N$ harmonic oscillators in which neighboring sites have their energies redistributed randomly. The sites $-N$ and $N$ are in contact with thermal reservoirs at different temperature $τ_-$ and $τ_+$. Kipnis, Marchioro, and Presutti \cite{KMP} proved that this model satisfies {}Fourier's law and that in the hydro

R. Carretero-Gonzalez, P. G. Kevrekidis, B. A. Malomed, D. J. Frantzeskakis

We construct a variety of novel localized states with distinct topological structures in the 3D discrete nonlinear Schr{ö}dinger equation. The states can be created in Bose-Einstein condensates trapped in strong optical lattices, and crystals built of microresonators. These new structures, most of which have no counterparts in lower dimensions, range from pu

Igor I. Smolyaninov

Optically active localized plasmon modes may be very abundant on a rough surface of a metal wire. Zero-point fluctuations of these modes are shown to produce local DC magnetization. Thus, the effect of these modes on the electron dephasing time is similar to the effect of magnetic impurities.

A. V. Plyukhin

The Rayleigh model of nonlinear Brownian motion is revisited in which the heavy particle of mass M interacts with ideal gas molecules of mass m via instantaneous collisions. Using the van Kampen method of expansion of the master equation, non-linear corrections to the Fokker-Planck equation are obtained up to sixth order in the small parameter m/M, improving

Guangyong Xu, H. Hiraka, G. Shirane, Jiefang Li

The lattice of (001)-oriented BiFeO$_3$ epitaxial thin film has been identified by synchrotron x-ray diffraction. By choosing proper scattering zones containing the fixed (001) reflection, we have shown that low-symmetry phases similar to a $M_A$ phase exist in the thin film at room temperature. These results demonstrate a change in phase stability from rhom

Carsten Honerkamp, Manfred Salmhofer

We describe how the fermionic functional renormalization group (fRG) flow of a Cooper+forward scattering problem can be continued into the superconducting state. This allows us to reproduce from the fRG flow the fundamental equations of the Eliashberg theory for superconductivity at all temperatures including the symmetry-broken phase. We discuss possible ex

S. A. Tarasenko, E. L. Ivchenko

As is well known the absorption of circularly polarized light in semiconductors results in optical orientation of electron spins and helicity-dependent electric photocurrent, and the absorption of linearly polarized light is accompanied by optical alignment of electron momenta. Here we show that the absorption of unpolarized light in a quantum well (QW) lead

S. Caprara, C. Di Castro, M. Grilli, D. Suppa

We calculate the Raman response contribution due to collective modes, finding a strong dependence on the photon polarizations and on the characteristic wavevectors of the modes. We compare our results with recent Raman spectroscopy experiments in underdoped cuprates, $La_{2-x}Sr_xCuO_4$ and $(Y_{1.97}Ca_{0.3})Ba_2CuO_{6.05}$, where anomalous low-energy peaks

Aranya B Bhattacherjee, Vikash Ranjan, Man Mohan

We consider the interaction between a single-mode quantized perturbing external field and a Bose-Einstein condensate (BEC) out of equilibrium. The usual Rabi type oscillations between the ground and the excited state of the coherent topological modes are observed with a Rabi frequency modified by the two-body atomic interactions. Taking into account the gran

H. Mera, P. Bokes, R. Godby

Ab-initio simulations of quantum transport commonly focus on a central region which is considered to be connected to infinite, periodic leads through which the current flows. The electronic structure of these distant leads is normally obtained from an equilibrium calculation, ignoring the self-consistent response of the leads to the current. We examine the c

V. M. Krasnov, T. Bauch, P. Delsing

We study thermal fluctuation phenomena in small Bi-2212 intrinsic Josephson junctions. Being able to measure switching currents of a {\it single} intrinsic junction, we observe that it's statistics can be very well described by thermal activation from a periodic Josephson potential with the sinusoidal current-phase relation. This is a direct evidence for

J. G. Caputo, L. Loukitch

We model the dynamics of point Josephson junctions in a 1D microstrip line using a wave equation with delta distributed sine nonlinearities. The model is suitable for both low T$_c$ and high T$_c$ systems (0 and $π$ junctions). For a single junction in the line, we found two limiting behaviors: the ohmic mode where the junction acts as a pure resistor which

Ivar Martin, Daniel Podolsky, Steven A. Kivelson

We study the effect of inhomogeneity of the paring interaction or the background potential on the superconducting transition temperature, T_c. In the weak coupling BCS regime, we find that inhomogeneity which is incommensurate with the Fermi surface nesting vectors enhances T_c relative to its value for the uniform system. For a fixed modulation strength we

L. C. Garcia de Andrade

Applications of non-Riemannian acoustic geometries in Bose-Einstein condensates (BEC) are considered. The first is the Minkowski-Cartan irrotational vortex acoustic geometry of nonlinear Schrödinger equations of BEC (Gross-Pitaeviskii (GP) equation). In this model, which is an alternative to the Riemannian acoustic geometry of phonons in BEC, the Cartan acou

Denis D. Sheka, Juan P. Zagorodny, Jean-Guy Caputo, Yuri Gaididei

We study the motion of a non-planar vortex in a circular easy-plane ferromagnet, which imitates a magnetic nanodot. Analysis was done using numerical simulations and a new collective variable theory which includes the coupling of Goldstone-like mode with the vortex center. Without magnetic field the vortex follows a spiral orbit which we calculate. When a ro

E. Gubankova, E. G. Mishchenko, F. Wilczek

Anisotropic pairing between fermion species with different fermi momenta opens two-dimensional areas of gapless excitations, thus producing a spatially homogeneous state with coexisting superfluid and normal fluids. This breached pairing state is stable and robust for arbitrarily small mismatch and weak p-wave coupling.

Pawel Buczek, Lorenzo Sadun, Janusz Wolny

A simple model of 1D structure based on a Fibonacci sequence with variable atomic spacings is proposed. The model allows for observation of the continuous transition between periodic and non-periodic diffraction patterns. The diffraction patterns are calculated analytically both using ``cut and project'' and ``average unit cell'' methods, tak

A. Zamora

We present results from extensive numerical simulations on the Lawrence-Doniach model within the lowest Landau level approximation in the unconventional spherical geometry. We study the in-layer pancake vortex density-density correlation function (intra-layer structure factor) and the layer-to-layer order-parameter correlation function along the direction pe

Etay Ziv, Robin Koytcheff, Manuel Middendorf, Chris Wiggins

We present a novel graph embedding space (i.e., a set of measures on graphs) for performing statistical analyses of networks. Key improvements over existing approaches include discovery of "motif-hubs" (multiple overlapping significant subgraphs), computational efficiency relative to subgraph census, and flexibility (the method is easily generalizabl

Luis F. Rodriguez, Laurent Loinard, Paola D'Alessio, David J. Wilner

Theoretical arguments suggest that protoplanetary disks around young stars should start small and grow with the addition of high angular momentum material to reach the radii of several hundred AUs that characterize the disks around optically visible T Tauri stars. Examples of much more compact disks, with radii much less than 100 AU, have been found around s

C. Pereira, P. Bergeron, F. Wesemael

We report the discovery of spectroscopic variations in GD 323, the prototypical DAB white dwarf. Simultaneous optical spectroscopic observations over five consecutive nights of GD 323 and of PG 1234+482, a non-variable comparison DA white dwarf of similar brightness, are used to reveal quasi-periodic variations in both the hydrogen and helium absorption line

A. Brunthaler, H. Falcke, G. C. Bower, M. F. Aller

A very detailed monitoring of a radio flare in the Seyfert I galaxy III Zw 2 with the VLA and the VLBA is presented. The relative astrometry in the VLBA observations was precise on a level of a few microarcseconds. Spectral and spatial evolution of the source are closely linked and these observations allowed us to study in great detail a textbook example of

F. Pont, F. Bouchy, C. Melo, N. C. Santos

We present the results of our high-resolution spectroscopic follow-up of 42 planetary transit candidates in Carina from the OGLE survey. This follow-up has already allowed the discovery of three new transiting exoplanets, OGLE-TR-111, 113 and 132, presented in earlier Letters (Bouchy et al. 2004, Pont et al. 2004). Here we analyse the data for the remaining

R. R. R. Reis, M. Makler, I. Waga

The possibility of unifying dark-matter and dark-energy has recently attracted considerable interest. In this so called quartessence scenario, a single component is responsible for both the clustering of matter and the accelerated expansion of the universe. A model archetype for such scenario is provided by the Chaplygin gas. Although this model is in agreem

L. Stawarz, A. Siemiginowska, M. Ostrowski, M. Sikora

The energy content of large-scale jets in FR I radio galaxies is still an open issue. Here we show that upper limits on the high-energy and very high-energy gamma-ray emission of the kpc-scale jet in M 87 radio galaxy imposed by EGRET, Whipple, and - most importantly - HEGRA and HESS observations, provide important constraints on the magnetic field strength

L. Stawarz, J. Kataoka

Here we report systematic comparison of the spectral properties of large-scale jets, hotspots and extended lobes in quasars and FR II radio galaxies recently observed with Chandra and ASCA. We argue that if the strong X-ray emission of the jet knots in these objects results from comptonisation of the CMB photons, as usually considered, the powerful large-sca

L. Stawarz, M. Sikora, M. Ostrowski, M. C. Begelman

We propose that the knots of the large-scale jets in powerful radio sources represent moving and separate portions of the jet matter, with the excess kinetic power. This can explain many morphological properties of quasar jets - like high knot-to-interknot brightness contrasts, frequency-independent knot profiles and almost universal extents of the knot regi

M. Sereno

Gravitational lensing by a spinning deflector in translational motion relative to the observer is discussed in the weak field, slow motion approximation. The effect of rotation, which generates an intrinsic gravito-magnetic field, separates from that due to radial motion. Corrections to the lens equation, deflection angle and time delay are derived.

U. Munari, A. Henden, A. Vallenari, H. E. Bond

Extensive optical and infrared photometry as well as low and high resolution spectroscopy are used as inputs in deriving robust estimates of the reddening, distance and nature of the progenitor of V838 Mon. The reddening is found to obey the R_V=3.1 law and amounts to (i) E(B-V)=0.86 from the interstellar NaI and KI lines, (ii) E(B-V)=0.88 from the energy di

J. L. Hou, C. G. Shu, S. Y. Shen, R. X. Chang

Based on the disk galaxy formation theory within the framework of standard LCDM hierarchical picture, we selected modelled DLAs, according to their observational criterion, by Monte Carlo simulation with the random inclinations being considered, to examine their observed properties. By best-fitting the predicted metallicity distribution to the observed ones,

A. V. Moiseev, D. V. Bizyaev, E. I. Vorobyov

We present results of Fabry-Perot and long-slit spectroscopy of the peculiar galaxy Arp 10. The ionized gas velocity field shows evidence for significant radial motions in both outer and inner galactic rings. Long-slit spectroscopy reveals gradients of age and metallicity of stellar population in agreement with the propagating nature of star formation in the

N. A. Koshelev

The scalar perturbations in inflationary models, based on a two-component diagonal non-linear sigma model, are considered. For inhomogeneities generated at an inflationary stage, the law of motion of the comoving curvature ${\cal R}$ is obtained (without using the slow roll approximations). A formal expressions for the power spectrum and its spectral index a

S. S. Komissarov

In this paper we report the results of axisymmetric relativistic MHD simulations for the problem of Kerr black hole immersed into a rarefied plasma with ''uniform'' magnetic field. The long term solution shows properties which are significantly different from those of the initial transient phase studied recently by Koide(2003). The topology o

C. Belfiore, M. Brescia, M. Capaccioli, O. Caputi

The VLT Survey Telescope (VST) is a 2.6m aperture, wide field, UV to I facility, to be installed at the European Southern Observatory (ESO) on the Cerro Paranal Chile. VST was primarily intended to complement the observing capabilities of VLT with wide-angle imaging for detecting and pre-characterising sources for further observations with the VLT.

Samar Safi-Harb, Jennifer West

The anomalous X-ray pulsars (AXPs) represent a growing class of neutron stars discovered at X-ray energies. While the nature of their multi-wavelength emission mechanism is still under debate, evidence has been recently accumulating in favor of their magnetar nature. Their study in the optical and infrared (IR) wavelengths has recently opened a new window to

Juerg Diemand, Ben Moore, Joachim Stadel

The Universe was nearly smooth and homogeneous before a redshift of z = 100, about 20 million years after the Big Bang. After this epoch, the tiny fluctuations imprinted upon the matter distribution during the initial expansion began to collapse because of gravity. The properties of these fluctuations depend on the unknown nature of dark matter, the determin

Paul Fabel

Endowed with natural topologies, the fundamental group of the Hawaiian earring continuously injects into the inverse limit of free groups. This note shows the injection fails to have a continuous inverse. Such a phenomenon was unexpected and appears to contradict results of another author.

Peter Orland

We consider a 2+1-dimensional SU(N) lattice gauge theory in an axial gauge with the link field U in the 1-direction set to one. The term in the Hamiltonian containing the square of the electric field in the 1-direction is non-local. Despite this non-locality, we show that weak-coupling perturbation theory in this term gives a finite vacuum-energy density to

Z. L. Yuan, A. J. Shields

We demonstrate a robust, compact and automated quantum key distribution system, based upon a one-way Mach-Zender interferometer, which is actively compensated for temporal drifts in the photon phase and polarization. The system gives a superior performance to passive compensation schemes with an average quantum bit error rate of 0.87% and a duty cycle of 99.

Gabriele Gionti

A discrete theory of gravity locally invariant under the Poincaré group is considered as in a companion paper. We define a first order theory, in the sense of Palatini, on the metric-dual Voronoi complex of a simplicial complex. We follow the same spirit of the continuum theory of General Relativity in the Cartan formalism. The field equations are carefully

V. Barger, D. Marfatia, K. Whisnant

We perform a comparative study of two methods of determining the survival probabilities of low, intermediate, and high energy solar neutrinos that emphasizes the general agreement between the Large Mixing Angle (LMA) solution and extant solar neutrino data. The first analysis is oscillation parameter-independent and the second analysis involves an approximat

Huy Tai Ha

In recent years, two different multigraded variants of Castelnuovo-Mumford regularity have been developed, namely multigraded regularity, defined by the vanishing of multigraded pieces of local cohomology modules, and the resolution regularity vector, defined by the multidegrees in a minimal free resolution. In this paper, we study the relationship between m

Huy Tai Ha

Let X be a smooth projective variety and let K be the canonical divisor of X. In this paper, we study embeddings of X given by adjoint line bundles of the form K+L, where L is an ample line bundle. When X is a regular surface (i.e. H^1(X, O_X) = 0), we obtain a numerical criterion for K+L to have property Np. When X is a regular variety of arbitrary dimensio

W. A. Rodrigues, Roldao da Rocha, J. Vaz

In this paper we investigate a hidden consequence of the hypothesis that Lagrangians and field equations must be invariant under active local Lorentz transformations. We show that this hypothesis implies in an equivalence between spacetime structures with several curvature and torsion possibilities.

J. -L. Lehners, P. Smyth, K. S. Stelle

Horava-Witten spacetimes necessarily include two branes of opposite tension. If these branes are BPS we are led to a puzzle: a negative tension brane should be unstable as it can loose energy by expanding, whereas a BPS brane should be stable as it resides at a minimum of the energy. We provide a detailed analysis of the energy of such braneworld spacetimes

Luigi Amico, Andreas Osterloh, Francesco Cataliotti

In the present work we demonstrate how to realize 1d-optical closed lattice experimentally, including a {\it tunable} boundary phase-twist. The latter may induce ``persistent currents'', visible by studing the atoms' momentum distribution. We show how important phenomena in 1d-physics can be studied by physical realization of systems of trapped a

M. Shifman, A. Yung

We consider non-Abelian 1/2 BPS flux tubes (strings) in a deformed N=2 supersymmetric gauge theory, with mass terms mu_{1,2} of the adjoint fields breaking N=2 down to N=1. The main feature of the non-Abelian strings is the occurrence of orientational moduli associated with the possibility of rotations of their color fluxes inside a global SU(N) group. The b

M. Goiran, M. Costes, J. M. Broto, F. C. Chou

We report an electron spin resonance (ESR) study of the s=1/2-Heisenberg pseudo-ladder magnet CaCu2O3 in pulsed magnetic fields up to 40 T. At sub-Terahertz frequencies we observe an ESR signal originating from a small amount of uncompensated spins residing presumably at the imperfections of the strongly antiferromagnetically correlated host spin lattice. Th

A Rodriguez-Prieto, A. Bergara

Light alkali metals have usually been considered as simple metals due to their monovalency and high conductivity. In these metals ionic pseudopotentials are weak and the nearly free electron model (NFE) becomes quite accurate at normal conditions. However, very recent experiments have shown that at high pressures their electronic properties deviate radically

I. Horvath, A. Alexandru, J. B. Zhang, Y. Chen

We have recently presented evidence that in configurations dominating the regularized pure-glue QCD path integral, the topological charge density constructed from overlap Dirac operator organizes into an ordered space-time structure. It was pointed out that, among other properties, this structure exhibits two important features: it is low-dimensional and geo

Kalin Vetsigian, Nigel Goldenfeld

We model the competition between recombination and point mutation in microbial genomes, and present evidence for two distinct phases, one uniform, the other genetically diverse. Depending on the specifics of homologous recombination, we find that global sequence divergence can be mediated by fronts propagating along the genome, whose characteristic signature

M. Joyce, F. Sylos Labini, A. Gabrielli, M. Montuori

We discuss some of the basic implications of recent results on galaxy correlations published by the SDSS collaboration. In particular we focus on the evidence which has been recently presented for the scale and nature of the transition to homogeneity in the galaxy distribution, and results which describe the dependence of clustering on luminosity. The two qu

H. Stenzel

One of the most precise measurements of the strong coupling constant alpha_s(MZ) is obtained in the context of global analyses of precision electroweak data. This article reviews the sensitivity of different electroweak observables to alpha_s and describes the perturbative uncertainties related to missing higher orders. The complete renormalisation scale dep

Burkhard Zink, Nikolaos Stergioulas, Ian Hawke, Christian D. Ott

We investigate new paths to black hole formation by considering the general relativistic evolution of a differentially rotating polytrope with toroidal shape. We find that this polytrope is unstable to nonaxisymmetric modes, which leads to a fragmentation into self-gravitating, collapsing components. In the case of one such fragment, we apply a simplified ad

R. Aloisio, P. Blasi, A. Galante, P. L. Ghia

In the last years a general consensus has emerged that, contrary to intuition, quantum-gravity effects may have relevant consequences for the propagation and interaction of high energy particles. This has given birth to the field of ``Phenomenological Quantum Gravity'' We review some of the aspects of this new, very exciting frontier of Physics.

M. H. Ernst

The universal power law tails of single particle and multi-particle time correlation functions are derived from a unifying point of view, solely using the hydrodynamic modes of the system. The theory applies to general correlation functions, and to systems more general than classical fluids. Moreover it is argued that the collisional transfer part of the str

M. Viel, J. Lesgourgues, M. G. Haehnelt, S. Matarrese

The matter power spectrum at comoving scales of (1-40) h^{-1} Mpc is very sensitive to the presence of Warm Dark Matter (WDM) particles with large free streaming lengths. We present constraints on the mass of WDM particles from a combined analysis of the matter power spectrum inferred from the large samples of high resolution high signal-to-noise Lyman-alpha

D. Grumiller

A local action is constructed describing the exact string black hole discovered by Dijkgraaf, Verlinde and Verlinde in 1992. It turns out to be a special 2D Maxwell-dilaton gravity theory, linear in curvature and field strength. Two constants of motion exist: mass M>1, determined by the level k, and U(1)-charge Q>0, determined by the value of the dilaton at

Tim Huege, Heino Falcke

We have developed a sophisticated model of the radio emission from extensive air showers in the scheme of coherent geosynchrotron radiation, providing a theoretical foundation for the interpretation of experimental data from current and future experiments. Having verified the model through comparison of analytic calculations, Monte Carlo simulations and hist

Richard Lednicky

The formalism allowing one to account for the effect of a finite space-time extent of particle production region is given. Its applications to the lifetime measurement of hadronic atoms produced by a high-energy beam in a thin target, as well as to the femtoscopy techniques widely used to measure space-time characteristics of the production processes, are di

S. V. Goloskokov, P. Kroll

We analyze electroproduction of light vector mesons at small Bjorken-x in an approach that includes the gluonic generalized parton distributions and a partonic subprocess, gamma g --> (q q-bar) g, q q-bar --> V. The subprocess is calculated to lowest order of perturbative QCD taking into account the transverse momenta of the quark and antiquark as well as Su

Nestor Sanchez, Emilio J. Alfaro, Enrique Perez

The interstellar medium seems to have an underlying fractal structure which can be characterized through its fractal dimension. However, interstellar clouds are observed as projected two-dimensional images, and the projection of a tri-dimensional fractal distorts its measured properties. Here we use simulated fractal clouds to study the relationship between

Florian Bauer

We study the renormalisation group running of the cosmological and the Newton constant, where the renormalisation scale is given by the inverse of the radius of the cosmological event horizon. In this framework, we discuss the future evolution of the universe, where we find stable de Sitter solutions, but also "big crunch"-like and "big rip"-

Norisuke Sakai, David Tong

Non-abelian gauge theories in the Higgs phase admit a startling variety of BPS solitons. These include domain walls, vortex strings, confined monopoles threaded on vortex strings, vortex strings ending on domain walls, monopoles threaded on strings ending on domain walls, and more. After presenting a self-contained review of these objects, including several

D. Schildknecht, B. G. Zakharov

We demonstrate that the transition photon radiation and pair creation can be interpreted as a diffractive phenomenon in terms of the light-cone wave functions in a way similar to the Good-Walker approach [6] to the diffraction dissociation. Our formulas for spectra agree with those obtained by Baier and Katkov [5] within the quasiclassical operator method. H

Xiaofeng Wang, Lifan Wang, Xu Zhou, Yuqing Lou

Type Ia supernovae (SNe Ia) provide us with a unique tool for measuring extragalactic distances and determining cosmological parameters. As a result, the precise and effective calibration for peak luminosities of SNe Ia becomes extremely crucial and thus is critically scrutinized for cosmological explorations. In this Letter, we reveal clear evidence for a t

D. M. Zumbuhl, J. B. Miller, D. Goldhaber-Gordon, C. M. Marcus

Conductance fluctuations in GaAs quantum dots with spin-orbit and Zeeman coupling are investigated experimentally and compared to a random matrix theory formulation that defines a number of regimes of spin symmetry depending on experimental parameters. Accounting for orbital coupling of the in-plane magnetic field, which can break time-reversal symmetry, yie

Xian-Hui Zhong, G. X. Peng, Ping-Zhi Ning

The properties of nuclear matter are discussed with the relativistic mean-field theory (RMF).Then, we use two models in studying the in-medium properties of $Θ^+$: one is the point-like $Θ^*$ in the usual RMF and the other is a K$π$N structure for the pentaquark. It is found that the in-medium properties of $Θ^+$ are dramatically modified by its internal str

Yong Wu, Jon Machta

The random field Ising model is studied numerically at both zero and positive temperature. Ground states are mapped out in a region of random and external field strength. Thermal states and thermodynamic properties are obtained for all temperatures using the the Wang-Landau algorithm. The specific heat and susceptibility typically display sharp peaks in the

N. Kiriushcheva, S. V. Kuzmin, D. G. C. McKeon

The canonical structure of the Einstein-Hilbert Lagrange density $L=\sqrt{-g}R$ is examined in two spacetime dimensions, using the metric density $h^{μν}\equiv \sqrt{-g}g^{μν}$ and symmetric affine connection $Γ_{σβ}^λ$ as dynamical variables. The Hamiltonian reduces to a linear combination of three first class constraints with a local SO(2,1) algebra. The f

Kenjiro Yanagi, Shigeru Furuichi, Ken Kuriyama

A generalized skew information is defined and a generalized uncertainty relation is established with the help of a trace inequality which was recently proven by J.I.Fujii. In addition, we prove the trace inequality conjectured by S.Luo and Z.Zhang. Finally we point out that Theorem 1 in {\it S.Luo and Q.Zhang, IEEE Trans.IT, Vol.50, pp.1778-1782 (2004)} is i

G. T. Rubin-Linares, H. Moya-Cessa

We propose a simple scheme to measure squeezing and phase properties of a harmonic oscillator. We treat in particular the case of a the field, but the scheme may be easily realized in ion traps. It is based on integral transforms of measured atomic properties as atoms exit a cavity. We show that by measuring atomic polarizations it is possible, after a given

P Blasiak, A Horzela, K A Penson, G H E Duchamp

We solve the boson normal ordering problem for (q(a*)a + v(a*))^n with arbitrary functions q and v and integer n, where a and a* are boson annihilation and creation operators, satisfying [a,a*]=1. This leads to exponential operators generalizing the shift operator and we show that their action can be expressed in terms of substitutions. Our solution is natur

Mahdi Amniat-Talab, Stephane Guerin, Hans-Rudolf Jauslin

We propose a robust and decoherence insensitive scheme to generate controllable entangled states of two three-level atoms interacting with an optical cavity and a laser beam. Losses due to atomic spontaneous transitions and to cavity decay are efficiently suppressed by employing fractional adiabatic passage and appropriately designed atom-field couplings. In

Jae Weon Lee, Dmitri V. Averin, Giuliano Benenti, Dima L. Shepelyansky

We discuss a deterministic model of detector coupled to a two-level system (a qubit). The detector is a quasi-classical object whose dynamics is described by the kicked rotator Hamiltonian. We show that in the regime of quantum chaos the detector acts as a chaotic bath and induces decoherence of the qubit. We discuss the dephasing and relaxation rates and de

Arvid J. Bessen

We obtain a query lower bound for quantum algorithms solving the phase estimation problem. Our analysis generalizes existing lower bound approaches to the case where the oracle Q is given by controlled powers Q^p of Q, as it is for example in Shor's order finding algorithm. In this setting we will prove a log (1/epsilon) lower bound for the number of app

Geza Toth, Otfried Guehne

We present entanglement witness operators for detecting genuine multipartite entanglement. These witnesses are robust against noise and require only two local measurement settings when used in an experiment, independent from the number of qubits. This allows detection of entanglement for an increasing number of parties without a corresponding increase in eff

S. Dumitru

The known approaches of number-phase problem (for a quantum oscillator) are mutually contradictory. All of them are subsequent in respect with the Robertson-Schrödinger uncertainty relation (RSUR). In oposition here it is proposed a new approacch aimed to be aboriginal as regard RSRUR. From the new perspective the Dirac's operators for vibrational number

Max Shpak

It was shown by Gillespie (1974) that if two genotypes produce the same average number of offspring on but have a different variance associated within each generation, the genotype with a lower variance will have a higher effective fitness. Specifically, the effective fitness is W(effective)=w-var/N, where w is the mean fitness, var is the variance in offspr

J. Marciak-Kozlowska, M. Kozlowski, M. Pelc

In this paper the heat signaling in microtubules (MT) is investigated. It is argued that for the description of the heat signaling phenomena in MT, the hyperbolic heat transport (HHT) equation must be used. It is shown that HHT is the Klein-Gordon (K-G) equation. The general solution for the K-G equation for MT is obtained. For the undistorted signal propaga

Xiaodong Chen

By extending original Kaluza-Klein theory to 6-dimension, the basic quantum field equations for 0-spin particle, 1-spin particle and 1/2 spin particle with mass >0 are directly derived from 6-dimensional Einstein equations. It shows that the current quantum field equations of basic particles become pure geometry properties under 6-dimension time-space. The f

G. M. Genkin

We show that the superfluid state (SF) of fermionic atoms exist only for the magnetic fields lesser than the critical magnetic field. This critical magnetic field is determined by the equality of the Zeeman energy splitting for atoms with different spin projections to the energy gap of fermionic atoms without a magnetic field. For magnetic fields usually usi

N. Arcis, D. F. Escande, M. Ottaviani

Within the traditional frame of reduced MHD, a new rigorous perturbation expansion provides the equation ruling the nonlinear growth and saturation of the tearing mode for any current gradient. The small parameter is the magnetic island width w. For the first time, the final equation displays at once terms of order w ln(1/w) and w which have the same magnitu

Timothy H. Boyer

The relativistic conservation law involving the center of energy is reviewed and illustrated using simple examples from classical electromagnetic theory. It is emphasized that this conservation law is parallel to the conservation laws for energy, linear momentum, and energy, in arising from the generators of the Poincare group for electromagnetic theory; yet

Xi Yang, James MacLachlan, Charles M. Ankenbrandt

An experimental procedure for measuring gamma-T has been developed and tested in two different measurements, with the gamma-T quads on and off. The results were compared to MAD calculations. The discrepancy between the measured gamma-T and the calculated gamma-T is less than 5%.

Shadow J. Q. Robinson, Alberto Escuderos, Larry Zamick

Calculations of the spectra of various even-even nuclei in the fp shell ({44}Ti, {46}Ti, {48}Ti, {48}Cr and {50}Cr) are performed with two sets of two-body interaction matrix elements. The first set consists of the matrix elements of the FPD6 interaction. The second set has the same T=1 two-body matrix elements as the FPD6 interaction, but all the T=0 two-bo

M. Wloch, D. J. Dean, J. R. Gour, M. Hjorth-Jensen

We report converged results for the ground and excited states and matter density of 16-O using realistic two-body nucleon-nucleon interactions and coupled-cluster methods and formalism developed in quantum chemistry. Most of the binding is obtained with the coupled-cluster singles and doubles approach. Additional binding due to three-body clusters (triples)

Hiroshi Iwase, Yoshiyuki Iwata, Takashi Nakamura, Konstantin Gudima

Double-differential cross sections of neutron production at angles from 0 to 110 degrees from many reactions induced by light and medium nuclei on targets from 12-C to 208-Pb, at several incident energies from 95 to 600 MeV/A have been measured recently at the Institute of Physical and Chemical Research (RIKEN) Ring Cyclotron in Japan and at the Heavy-Ion Me

H. van Hees, R. Rapp

We investigate properties of the Delta(1232) and nucleon spectral functions at finite temperature and baryon density within a hadronic model. The medium modifications of the Delta consist of a renormalization of its pion-nucleon cloud and resonant pi-Delta scattering. Underlying coupling constants and form factors are determined by the elastic π-N scattering

G. Rakness

Measurements are reported of the production of high energy pi^0 mesons at large pseudorapidity, coincident with charged hadrons at mid-rapidity, for proton+proton and deuteron+gold collisions at sqrt{s_{NN}}=200 GeV. The p+p cross section for inclusive pi^0 production follows expectations from next-to-leading order perturbative QCD. A suppression of the back

Souichi Murata

In this paper it is shown that Riemann invariants are invariant under nonclassical symmetries of a hyperbolic system. As a specific example, we study the one-dimensional shallow water equations on the flat and present another type invariance under nonclassical symmetries.

T. A. Larsson

A simple plausibility argument is given.

Nguyen Cong Phuc, Igor E. Verbitsky

The existence problem is solved, and global pointwise estimates of solutions are obtained for quasilinear and Hessian equations of Lane-Emden type, including the following two model problems: $ -Δ_p u = u^q + μ$ and $F_k[-u] = u^q + μ$, $u > 0$, on $R^n$, or on a bounded domain $Ω$. Here $Δ_p$ is the p-Laplacian, and $F_k[u]$ is the $k$-Hessian defined as th

Christopher J. Leininger, Dan Margalit

Let B_n be the braid group on n strands, with n at least 4, and let Mod(S) be the extended mapping class group of the sphere with n+1 punctures. We show that the abstract commensurator of B_n is isomorphic to a semidirect product of Mod(S) with a group we refer to as the transvection subgroup, Tv(B_n). We also show that Tv(B_n) is itself isomorphic to a semi

Ian M. Aberbach, Laura Ghezzi, Huy Tai Ha

We study the relation type question, raised by C. Huneke, which asks whether for a complete equidimensional local ring R there exists a uniform bound for the relation type of parameter ideals. Wang gave a positive answer to this question when the non-Cohen-Macaulay locus of R, denoted by NCM(R), has dimension zero. We first present an example, due to the fir

Denis Bonnay

This paper presents two different ways of extracting the computational content of formal proofs in arithmetic. The first one corresponds to Kreisel's No-counterexample Interpretation. based on Ackermann consistency proof. We show the link with recent work by Krivine on classical realizability. Finally, we discuss the various degrees of modularity of both

Eric Bedford, John Smillie

We consider the complexification of the Henon family of quadratic diffeomorphisms of the plane, and the region of parameter space corresponding to complex horseshoes. We discuss some conjectures about the global topology of the complex horseshoe locus.

Daniel G. Davis

Let G be a closed subgroup of G_n, the extended Morava stabilizer group. Let E_n be the Lubin-Tate spectrum, let X be an arbitrary spectrum with trivial G-action, and define E^(X) to be L_K(n)(E_n ^ X). We prove that E^(X) is a continuous G-spectrum with a G-homotopy fixed point spectrum, defined with respect to the continuous action. Also, we construct a de

A. Gerasimov, S. Kharchev, D. Lebedev, S. Oblezin

This paper is a short account of the construction of a new class of the infinite-dimensional representations of the quantum groups. The examples include finite-dimensional quantum groups $U_q(\mathfrak{g})$, Yangian $Y(\mathfrak{g})$ and affine quantum groups at zero level $U_q(\hat{\mathfrak{g}})_{c=0}$ corresponding to an arbitrary finite-dimensional semis