March 2006 arXiv papers — page 6

Dmitri V. Averin

The paper discusses dynamics of quantum measurements in mesoscopic solid-state systems. The aim is to show how the general ideas of the quantum measurement theory play out in the realistic models of actual mesoscopic detectors. The two general models of ballistic and tunneling detectors are described and studied quantitatively. Simple transformation cycle de

B. J. Senkowicz, A. A. Polyanskii, R. J. Mungall, E. E. Hellstrom

Carbon-doped magnesium diboride was fabricated from pre-reacted pure MgB2 by mechanical alloying. The sample set had excellent critical current densities Jc(8T,4.2K) ranging from 15-60 kA/cm2, depending on composition. Magneto-optical imaging detected regions up to 0.5 mm in size which were nearly 100% dense with Jc 2-6 times that of the matrix. Evaluation o

Eduardo R. Hernandez, Jorge Iniguez

Recent experiments have obtained the melting line of sodium up to pressures of about 130 GPa, finding that the melting line from the {\em bcc} phase reaches a maximum at a temperature of {\em c.a.} 1000 K and a pressure of 31 GPa, and at higher pressures the fusion temperature decreases continuously up to 118 GPa. Here we report results of a study based on f

A. M. Somoza, J. Prior, M. Ortuno

We have studied numerically the fluctuations of the conductance, $g$, in two-dimensional, three-dimensional and four-dimensional disordered non-interacting systems. We have checked that the variance of $\ln g$ varies with the lateral sample size as $L^{2/5}$ in three-dimensional systems, and as a logarithm in four-dimensional systems. The precise knowledge o

M. Aichinger, S. A. Chin, E. Krotscheck, E. Rasanen

We investigate the effects of impurities and changing ring geometry on the energetics of quantum rings under different magnetic field strengths. We show that as the magnetic field and/or the electron number are/is increased, both the quasiperiodic Aharonov-Bohm oscillations and various magnetic phases become insensitive to whether the ring is circular or squ

T. Meunier, I. T. Vink, L. H. Willems van Beveren, F. H. L. Koppens

We propose and implement a non-destructive measurement that distinguishes between two-electron spin states in a quantum dot. In contrast to earlier experiments with quantum dots, the spins are left behind in the state corresponding to the measurement outcome. By measuring the spin states twice within a time shorter than the relaxation time, T1, correlations

Dumitru Mihalache, Dumitru Mazilu, Boris A. Malomed, Falk Lederer

We perform accurate investigation of stability of localized vortices in an effectively two-dimensional (&#34;pancake-shaped&#34;) trapped BEC with negative scattering length. The analysis combines computation of the stability eigenvalues and direct simulations. The states with vorticity S=1 are stable in a third of their existence region, $0<N<(1/3)N_{\max}^

Sabine Stock, Baptiste Battelier, Vincent Bretin, Zoran Hadzibabic

In this short review we present our recent results concerning the rotation of atomic Bose-Einstein condensates confined in quadratic or quartic potentials, and give an overview of the field. We first describe the procedure used to set an atomic gas in rotation and briefly discuss the physics of condensates containing a single vortex line. We then address the

Ugo Tartaglino, Ion M. Sivebaek, Bo N. J. Persson, Erio Tosatti

The properties of butane (C4H10) lubricants confined between two approaching solids are investigated by a model that accounts for the curvature and elastic properties of the solid surfaces. We consider the linear n-butane and the branched iso-butane. For the linear molecule, well defined molecular layers develop in the lubricant film when the width is of the

J. Scola, A. Pautrat, C. Goupil, Ch. Simon

We report measurements and analysis of the voltage noise due the to vortex motion, performed in superconducting Niobium micro-bridges. Noise in such small systems exhibits important changes from the behavior commonly reported in macroscopic samples. In the low biasing current regime, the voltage fluctuations are shown to deviate substantially from the Gaussi

Hwee Kuan Lee, Yutaka Okabe

We present the multispin coding for the nonequlibrium reweighting method of the Monte Carlo simulation, that was developed by the present authors. As an illustration, we treat the driven diffusive lattice gas model. We use the multispin coding technique both for the spin update and for the calculation of the histogram of incremental weights, which is needed

Manuel V. Ramallo, Jesus Mosqueira, Carlos Carballeira, Felix Soto

We first summarize our recent observations, through magnetization measurements in different low-Tc superconductors, of a rather sharp disappearance of the superconducting fluctuations in the normal state when the magnetic field approaches Hc2(0), the upper critical field extrapolated to T=0K. We propose that a crude phenomenological description of the observ

Sudeshna Chattopadhyay, Alokmay Datta

Au nanoparticles with near perfect monodispersity in shape and size self-assemble, very slowly and at room temperature, on polystyrene films for film thickness < 4R_{g}$, R_{g} being unperturbed polymer gyration radius. Nanoparticle shape and size can be tuned, without sacrificing monodispersity, by changing polymer film thickness. Self-assembly is caused by

Yatendra S. Jain

A new approach based on macro-orbital representation of a conduction electron in a solid has been used to discover some untouched aspects of the phonon induced attraction between two electrons and to lay the basic foundations of a general theory of superconductivity applicable to widely different solids. To this effect we first analyze the net hamiltonian, H

V. A. Brazhnyi, V. V. Konotop, V. Kuzmiak

On examples of Bose-Einstein condensates embedded in two-dimensional optical lattices we show that in nonlinear periodic systems modulational instability and inter-band tunneling are intrinsically related phenomena. By direct numerical simulations we found that tunneling results in attenuation or enhancement of instability. On the other hand, instability res

Hongming Weng, Jinming Dong

A number of transition-metal (TM) doped group-IV semiconductors, R$_{x}$Y$_{1-x}$ (R=Cr, Mn and Fe; Y=Si, Ge), have been studied by the first principles calculations. The obtained results show that antiferromagnetic (AFM) order is energetically more favored than ferromagnetic (FM) order in Cr-doped Ge and Si with $x$=0.03125 and 0.0625. In 6.25% Fe-doped Ge,

Hwee Kuan Lee, Yutaka Okabe

A model consisting of random interacting anti-ferromagnetic (AF) grains coupled to a ferromagnetic (FM) layer is developed to study the exchange bias phenomenon. This simple model is able to describe several exchange bias behavior observed in real materials. Shifts in hysteresis loops are observed as a function of cooling field and average grain size. We est

Hongming Weng, Xiaoping Yang, Jinming Dong, H. Mizuseki

The Co-doped anatase TiO$_{2}$, a recently discovered room-temperature ferromagnetic insulator, has been studied by the first-principles calculations in the pseudo-potential plane-wave formalism within the local-spin-density approximation (LSDA), supplemented by the full-potential linear augmented plane wave (FP-LAPW) method. Emphasis is placed on the depend

Y. Chushak, A. Travesset

The free energy of a crystalline domain coexisting with a liquid phase on a spherical vesicle may be approximated by an elastic or stretching energy and a line tension term. The stretching energy generally grows as the area of the domain, while the line tension term grows with its perimeter. We show that if the crystalline domain contains defect arrays consi

Hongming Weng, Xiangang Wan, Jian Zhou, Jinming Dong

First-principles calculations with the full-potential linearized augmented plane-wave (FP-LAPW) method have been performed to investigate detailed electronic and linear optical properties of Sr$_{2}$CuO$_{2}$Cl$_{2}$, which is a classical low-dimensional antiferromagnet (AFM) charge transfer ({\it CT}) insulator. Within the local-spin-density approximation (

V. Sih, H. Knotz, J. Stephens, V. R. Horowitz

Time-resolved Kerr rotation spectroscopy as a function of pump-probe distance, voltage and magnetic field is used to measure the momentum-dependent spin splitting energies in GaAs and InGaAs epilayers. The strain of the samples can be reproducibly controlled in the cryostat using three- and four-point bending applied with a mechanical vise. We find that the

A. Cottet, T. Kontos, W. Belzig, C. Schonenberger

We consider electronic current transport through a ballistic one-dimensional quantum wire connected to two ferromagnetic leads. We study the effects of the spin-dependence of interfacial phase shifts (SDIPS) acquired by electrons upon scattering at the boundaries of the wire. The SDIPS produces a spin splitting of the wire resonant energies which is tunable

D. A. Ivanov, M. A. Skvortsov

We analyze the perturbative series of the Keldysh-type sigma-model proposed recently for describing the quantum mechanics with time-dependent Hamiltonians from the unitary Wigner-Dyson random-matrix ensemble. We observe that vertices of orders higher than four cancel, which allows us to reduce the calculation of the energy-diffusion constant to that in a spe

V. Juricic, M. B. Silva Neto, C. Morais Smith

We study the static magnetic correlations in lightly doped La(2-x)Sr(x)CuO(4) within the framework of a dipolar frustration model for a canted antiferromagnet. We show that the stability of the canted Neel state for x<2% is due to the Dzyaloshinskii-Moriya and XY anisotropies. For higher doping the ground state is unstable towards a helicoidal magnetic phase

Carsten Timm

It is predicted that III-V diluted magnetic semiconductors can exhibit stripe-like modulations of magnetization and carrier concentration. This inhomogeneity results from the strong dependence of the magnetization on the carrier concentration. Within Landau theory, a characteristic temperature T* below the Curie temperature is found so that below T* the equi

C. Klempt, T. van Zoest, T. Henninger, O. Topic

We show that light-induced atom desorption (LIAD) can be used as a flexible atomic source for large Rb-87 and K-40 magneto-optical traps. The use of LIAD at short wavelengths allows for fast switching of the desired vapor pressure and permits experiments with long trapping and coherence times. The wavelength dependence of the LIAD effect for both species was

Dimitris Achlioptas, Aaron Clauset, David Kempe, Cristopher Moore

Understanding the structure of the Internet graph is a crucial step for building accurate network models and designing efficient algorithms for Internet applications. Yet, obtaining its graph structure is a surprisingly difficult task, as edges cannot be explicitly queried. Instead, empirical studies rely on traceroutes to build what are essentially single-s

R. M. Hueckstaedt, J. H. Hunter, R. V. E. Lovelace

In order to understand star formation it is important to understand the dynamics of atomic and molecular clouds in the interstellar medium (ISM). Nonlinear hydrodynamic flows are a key component to the ISM. One route by which nonlinear flows arise is the onset and evolution of interfacial instabilities. Interfacial instabilities act to modify the interface b

R. P. Deo, D. M. Crenshaw, S. B. Kraemer

We present a study of the nuclear morphology of a sample of narrow- and broad-line Seyfert 1 galaxies (NLS1&#39;s and BLS1&#39;s) based on broad-band images in the Hubble Space Telescope archives. In our previous study, we found that large-scale stellar bars at > 1 kpc from the nucleus are more common in NLS1&#39;s than BLS1&#39;s. In this paper we find that

Jacqueline A. Hodge, Avinash A. Deshpande

We model the complex distribution of atomic hydrogen (HI) in the interstellar medium (ISM) assuming that it is driven entirely by supernovae (SN). We develop and assess two different models. In the first approach, the simulated volume is randomly populated with non-overlapping voids of a range of sizes. This may relate to a snapshot distribution of supernova

M. D. Reed, J. R. Eggen, A. -Y. Zhou, D. M. Terndrup

We continue our programme of extended single-site observations of pulsting subdwarf B (sdB) stars and present the results of extensive time series photometry to resolve the pulsation spectra for use in asteroseismological analyses. PG 0154+182, HS 1824+5745, and HS 2151+0857 were observed at the MDM Observatory during 2004 and 2005. Our observations are suff

V. Das, D. M. Crenshaw, R. P. Deo, S. B. Kraemer

We present a study of high-resolution long-slit spectra of the narrow-line region (NLR) in NGC 1068 obtained with the Space Telescope Imaging Spectrograph (STIS) aboard The Hubble Space Telescope (HST). The spectra were retrieved from the Multimission Archive at Space Telescope (MAST) obtained from two visits and seven orbits of HST time. We also obtained ME

Atsunori Yonehara

We propose a proper method to measure the size of the narrow line region (NLR) in distant quasars. The apparent angular size of the NLR is, in general, too small to resolve technically. However, it is possible to map the NLR if with gravitational lensing. In our method, we directly compare the observed image of the NLR with the expected lensed images of the

Jay P. Dunn, Brian Jackson, Rajesh P. Deo, Chris Farrington

Using the Multimission Archives at Space Telescope (MAST), we have extracted spectra and determined continuum light curves for 175 Seyfert Galaxies that have been observed with the International Ultraviolet Explorer (IUE) and the Faint Object Spectrograph (FOS) on the Hubble Space Telescope (HST). To obtain the light curves as a function of Julian Date, we u

Amanda J. Smith, Carole A. Haswell, Robert I. Hynes

We present high quality optical spectroscopy of the SU UMa-subtype dwarf nova, VW Hyi taken while the system was in quiescence. An S-wave is executed by the emission cores of the Hydrogen Balmer lines and by the emission lines of He I, Ca II, Fe II and He II. Using Doppler tomography we show it originates in the accretion stream-disc impact region. The He II

D. R. Bergman, G. B. Thomson, T. Abu-Zayyad, G. Hughes

Interactions between cosmic ray protons and the photons of the cosmic microwave background radiation, as well as the expansion of the universe, cause cosmic rays to lose energy in a way that depends on the distance from the cosmic nray source to the earth. Because of this, there is a correlation between cosmic ray energies and the average redshift of their o

S. Dall&#39;Osso, G. L. Israel, L. Stella

We further discuss the Unipolar Inductor Model (UIM) coupled to GW emission (Dall&#39;Osso et al. 2005) and compare it to observed properties of the two candidate ultrashort period binaries RX J0806+15 and RX J1914+24 . We consider the measured orbital periods, period derivatives and inferred X-ray luminosities of these two sources and find constraints on sy

Nickolay Y. Gnedin, Xiaohui Fan

We show that numerical simulations of reionization that resolve the Lyman Limit systems (and, thus, correctly count absorptions of ionizing photons) have converged to about 10% level for 5<z<6.2 and are in reasonable agreement (within 10%) with the SDSS data in this redshift interval. The SDSS data thus constraint the redshift of overlap of cosmic HII region

Knut A. G. Olsen, Robert D. Blum, Andrew W. Stephens, Tim J. Davidge

We discuss H and K observations of three fields in the bulge and disk of M31 obtained with the Altair adaptive optics system and NIRI instrument on Gemini North. These are the highest resolution and deepest near-infrared observations obtained to date of the inner regions of M31, and demonstrate the promise of ground-based adaptive optics for studying the cro

Jason M. Kirk, Derek Ward-Thompson, Richard M. Crutcher

We have mapped linearly polarized dust emission from the prestellar cores L1498 and L1517B with the James Clerk Maxwell Telescope (JCMT) using the Submillimetre Common User Bolometer Array (SCUBA) and its polarimeter SCUBAPOL at a wavelength of 850um. We use these measurements to determine the plane-of-sky magnetic field orientation in the cores. In L1498 we

Herve Wozniak, Nicolas Champavert

We have made hydro/N-body simulations with and without star formation to shed some light on the conditions under which a central kinematically cold stellar component (characterized by a velocity dispersion drop or σ-drop) could be created in a hot medium (e.g. a bulge) and survive enough time to be observed. We found that the timescale for a σ-drop formation

H. Sana, E. Gosset, G. Rauw, H. Sung

This paper is the first of a series dedicated to the X-ray properties of the young open cluster NGC 6231. Our data set relies on an XMM-Newton campaign of a nominal duration of 180 ks and reveals that NGC 6231 is very rich in the X-ray domain too. Indeed, 610 X-ray sources are detected in the present field of view, centered on the cluster core. The limiting

Joanna M. Rankin, Svetlana A. Suleymanova

Pulsar B0943+10 is well known for its `B&#39; (burst) mode, characterized by accurately drifting subpulses, in contrast to its chaotic `Q&#39; (quiet) mode. Six new Arecibo observations at 327 MHz with durations of 2+ hours each have shed considerable light on the modal dynamics of this pulsar. Of these, three were found to be exclusively `B&#39; mode, and t

S. W. Campbell, J. C. Lattanzio, L. M. Elliott

[Abridged] Norris et al. (1981) found that there was a distinct lack of cyanogen-strong (CN-strong) stars in their sample of AGB stars, as compared to their sample of RGB stars (which had roughly equal numbers of CN-normal and CNstrong stars). Similar features have been discovered in the AGB populations of other clusters. Unfortunately all of these studies s

Sarah Brough, Duncan Forbes, Virginia Kilborn, Warrick Couch

We examine a possible supergroup in the direction of the Eridanus constellation using 6dF Galaxy Survey second data release (6dFGS DR2) positions and velocities together with 2MASS and HyperLEDA photometry. We perform a friends-of-friends analysis to determine which galaxies are associated with each substructure before examining the properties of the constit

Louis E. Strigari, James S. Bullock, Manoj Kaplinghat, Andrey V. Kravtsov

We use measurements of the stellar velocity dispersion profile of the Fornax dwarf spheroidal galaxy to derive constraints on its dark matter distribution. Though the data are unable to distinguish between models with small cores and those with cusps, we show that a large > 1 kpc dark matter core in Fornax is highly implausible. Irrespective of the origin of

Masumi Kasai, Hideki Asada, Toshifumi Futamase

The backreaction of nonlinear inhomogeneities to the cosmic expansion is re-analyzed in the framework of general relativity. Apparent discrepancies regarding the effect of the nonlinear backreaction, which exist among the results of previous works in different gauges, are resolved. By defining the spatially averaged matter energy density as a conserved quant

George F. R. Ellis

After a survey of the present state of cosmological theory and observations, this article discusses a series of major themes underlying the relation of philosophy to cosmology. These are: A: The uniqueness of the universe; B: The large scale of the universe in space and time; C: The unbound energies in the early universe; D: Explaining the universe -- the qu

David M. Hall, Turab Lookman, Glenn H. Fredrickson, Sanjoy Banerjee

We introduce a mesoscale method for simulating hydrodynamic transport and self assembly of inhomogeneous polymer melts in pressure driven and drag induced flows. This method extends dynamic self consistent field theory (DSCFT) into the hydrodynamic regime where bulk material transport and viscoelastic effects play a significant role. The method combines four

Kenley Jung, Dimitri Shlyakhtenko

Suppose $N$ is a diffuse, property T von Neumann algebra and X is an arbitrary finite generating set of selfadjoint elements for N. By using rigidity/deformation arguments applied to representations of N in full matrix algebras, we deduce that the microstate spaces of X are asymptotically discrete up to unitary conjugacy. We use this description to show that

Joseph M. Renes, Graeme Smith

We provide a simple security proof for prepare & measure quantum key distribution protocols employing noisy processing and one-way postprocessing of the key. This is achieved by showing that the security of such a protocol is equivalent to that of an associated key distribution protocol in which, instead of the usual maximally-entangled states, a more genera

D. Grupe, D. N. Burrows, S. K. Patel, C. Kouveliotou

We report the results of the \chandra observations of the \swift-discovered short Gamma-Ray Burst GRB 050724. \chandra observed this burst twice, about two days after the burst and a second time three weeks later. The first \chandra pointing occurred at the end of a strong late-time flare. About 150 photons were detected during this 49.3 ks observation in th

J. I. Katz

I consider how physical processes scale over eight orders of magnitude in black hole mass, from stellar masses in gamma-ray bursts (GRB) and black-hole X-ray binaries (BHXRB) to supermassive active galactic nuclei (AGN). Accretion rates onto stellar mass black holes range over more than sixteen orders of magnitude, from the lower luminosity BHXRB to GRB. The

Kris T. Delaney, Carlo Pierleoni, D. M. Ceperley

A first-order liquid-liquid phase transition in high-pressure hydrogen between molecular and atomic fluid phases has been predicted in computer simulations using ab initio molecular dynamics approaches. However, experiments indicate that molecular dissociation may occur through a continuous crossover rather than a first-order transition. Here we study the na

Matsuo Sato

We examine whether the free energy of N=4 super Yang-Mills theory (SYM) in four dimensions corresponds to the partition function of the AdS_5 x S^5 superstring when corresponding operators are inserted into both theories. We obtain a formal free energy of N=4 U(N) SYM in four dimensions generated by the Feynman graph expansion to all orders of the &#39;t Hoo

D. C. Latimer

In Phys. Rev. A 70, 032104 (2004), M. Montesinos and G. F. Torres del Castillo consider various symplectic structures on the classical phase space of the two-dimensional isotropic harmonic oscillator. Using Dirac&#39;s quantization condition, the authors investigate how these alternative symplectic forms affect this system&#39;s quantization. They claim that

Joseph F. Hennawi, Jason X. Prochaska, Scott Burles, Michael A. Strauss

With close pairs of quasars at different redshifts, a background quasar sightline can be used to study a foreground quasar&#39;s environment in absorption. We search 149 moderate resolution background quasar spectra, from Gemini, Keck, the MMT, and the SDSS to survey Lyman Limit Systems (LLSs) and Damped Ly-alpha systems (DLAs) in the vicinity of 1.8 < z < 4

O. Garcia, B. Deissler, K. J. Hughes, J. M. Reeves

A Michelson interferometer using Bose-Einstein condensates is demonstrated with coherence times of up to 44 ms and arm separations up to 0.18 mm. This arm separation is larger than that observed for any previous atom interferometer. The device uses atoms weakly confined in a magnetic guide and the atomic motion is controlled using Bragg interactions with an

N. M. R. Peres, A. H. Castro Neto, F. Guinea

We study the problem of Dirac fermion confinement in graphene in the presence of a perpendicular magnetic field B. We show, analytically and numerically, that confinement leads to anomalies in the electronic spectrum and to a magnetic field dependent crossover from \sqrt{B}, characteristic of Dirac-Landau level behavior, to linear in B behavior, characterist

Shoichi Ichinose

We present a graphical representation of the supersymmetry and a C-program for the graphical calculation. Calculation is demonstrated for 4D Wess-Zumino model and for Super QED. The chiral operators are graphically expressed in an illuminating way. The tedious part of SUSY calculation, due to manipulating chiral suffixes, reduces considerably. The applicatio

K. R. S. Balaji, Bjorn Garbrecht

Single field baryogenesis, a scenario for Dirac leptogenesis sourced by a time-dependent scalar condensate, is studied. We compare the creation of the charge asymmetry by the perturbative decay of the condensate with the nonperturbative decay, a process of particle production commonly known in the context of inflation as preheating. The nonperturbative chann

David M. Hall, Turab Lookman, Glenn H. Fredrickson, Sanjoy Banerjee

We introduce a mesoscale technique for simulating the structure and rheology of block copolymer melts and blends in hydrodynamic flows. The technique couples dynamic self consistent field theory (DSCFT) with continuum hydrodynamics and flow penalization to simulate polymeric fluid flows in channels of arbitrary geometry. We demonstrate the method by studying

Patricia Ball, Roman Zwicky

The dominant theoretical uncertainty in extracting |V_td/V_ts| from the ratio of branching ratios R=B(B->(rho,omega)gamma)/B(B->K* gamma) is given by the ratio of form factors xi=T_1^{B->K*}(0)/T_1^{B->rho}(0). We re-examine xi in the framework of QCD sum rules on the light-cone, taking into account hitherto neglected SU(3)-breaking effects. We find xi=1.17

Cédric Lorcé

Recently, Diakonov and Petrov have suggested a formalism in the Relativistic Mean Field Approximation allowing one to derive the 3-, 5-, 7-,... quark wavefunctions for the octet, decuplet and antidecuplet. They have used this formalism and many strong approximations in order to estimate the exotic Theta+ width. The latter has been estimated to ~4 MeV. Beside

Ting Yu, J. H. Eberly

We demonstrate in straightforward calculations that even under ideally weak noise the relaxation of bipartite open quantum systems contains elements not previously encountered in quantum noise physics. While additivity of decay rates is known to be generic for decoherence of a single system, we demonstrate that it breaks down for bipartite coherence of even

Gorjan Alagic, Cristopher Moore, Alexander Russell

Daniel Simon&#39;s 1994 discovery of an efficient quantum algorithm for solving the hidden subgroup problem (HSP) over Z_2^n provided one of the first algebraic problems for which quantum computers are exponentially faster than their classical counterparts. In this paper, we study the generalization of Simon&#39;s problem to arbitrary groups. Fixing a finite

Rui Carvalho, Michael Batty

Here we extract the geographical addresses of authors in the Citeseer database of computer science papers. We show that the productivity of research centres in the United States follows a power-law regime, apart from the most productive centres for which we do not have enough data to reach definite conclusions. To investigate the spatial distribution of comp

Koji Nuida

Given a reflection $r$ in a Coxeter group $W$ (possibly of infinite rank), we consider the subgroup of $W$ generated by the reflections in $W$ having (-1)-eigenvectors orthogonal to the (-1)-eigenvector of $r$. In this paper, we determine completely when this subgroup is finitely generated, by using preceding results on centralizers of reflections. This resu

Ben Gripaios, Stephen M. West

Many models of electroweak symmetry-breaking with an extended Higgs sector exhibit improved naturalness, wherein the new physics scale, at which quadratic divergences of Higgs mass parameters due to top quark loops are cut off, can be pushed beyond the reach of the Large Hadron Collider without unnatural fine tuning. Such models include examples where the ne

Prasanta Mahato

In the Einstein-Cartan space $U_4$, an axial vector torsion together with a scalar field connected to a local scale factor have been considered. By combining two particular terms from the SO(4,1) Pontryagin density and then modifying it in a SO(3,1) invariant way, we get a Lagrangian density with Lagrange multipliers. Then under FRW-cosmological background,

Daniela Kühn, Deryk Osthus

Let H be any graph. We determine (up to an additive constant) the minimum degree of a graph G which ensures that G has a perfect H-packing (also called an H-factor). More precisely, let delta(H,n) denote the smallest integer t such that every graph G whose order n is divisible by |H| and with delta(G) > t contains a perfect H-packing. We show that delta(H,n)

Fernando Marchesano

The D6-brane spectrum of type IIA vacua based on twisted tori and RR background fluxes is analyzed. In particular, we compute the torsion factors of the (co)homology groups H_n and describe the effect that they have on D6-brane physics. For instance, the fact that H_3 contains Z_N subgroups explains why RR tadpole conditions are affected by geometric fluxes.

T. Dent, G. K. Leontaris, A. Psallidas, J. Rizos

We discuss renormalization effects on neutrino masses and mixing angles in a supersymmetric string-inspired SU(4) X SU(2)_L X SU(2)_R X U(1)_X model, with matter in fundamental and antisymmetric tensor representations and singlet Higgs fields charged under the anomalous U(1)_X family symmetry. The quark, lepton and neutrino Yukawa matrices are distinguished

M. J. Madsen, D. L. Moehring, P. Maunz, R. N. Kohn

We demonstrate ultrafast coherent coupling between an atomic qubit stored in a single trapped cadmium ion and a photonic qubit represented by two resolved frequencies of a photon. Such ultrafast coupling is crucial for entangling networks of remotely-located trapped ions through photon interference, and is also a key component for realizing ultrafast quantum

K. P. Schmidt, M. Grüninger, G. S. Uhrig

The key feature of an orbital wave or orbiton is a significant dispersion, which arises from exchange interactions between orbitals on distinct sites. We study the effect of a coupling between orbitons and phonons in one dimension using continuous unitary transformations (CUTs). Already for intermediate values of the coupling, the orbiton band width is stron

T. Suebsuwong, J. Malzac, E. Jourdain, A. Marcowith

We extend the investigation of general relativistic effects on the observed X-ray continuum of Kerr black holes in the context of the light bending model (Miniutti & Fabian, 2004). Assuming a ring-like illuminating source, co-rotating with the underlying accretion disk, we study the shape and normalisation of the primary and disc reflected continuum as well

N. A. Pertsev, H. Kohlstedt

The influence of depolarizing field on the magnitude and stability of a uniform polarization in ferroelectric capacitors and tunnel junctions is studied using a nonlinear thermodynamic theory. It is predicted that, in heterostructures involving strained epitaxial films and metal electrodes, the homogeneous polarization state may remain stable against transfo

Nicola Omodei

The GLAST Large Area Telescope (LAT) is the next generation satellite experiment for high-energy gamma-ray astronomy. It is a pair conversion telescope built with a plastic anticoincidence shield, a segmented CsI electromagnetic calorimeter, and the largest silicon strip tracker ever built. It will cover the energy range from 30 MeV to 300 GeV, shedding ligh

Giovanni Villadoro

We present the complete calculation of the SU(3)-breaking corrections to the hyperon vector form factors up to O(p^4) in the Heavy Baryon Chiral Perturbation Theory. Because of the Ademollo-Gatto theorem, at this order the results do not depend on unknown low energy constants and allow to test the convergence of the chiral expansion. We complete and correct

M. Hairer, A. Ohashi

We develop a theory of ergodicity for a class of random dynamical systems where the driving noise is not white. The two main tools of our analysis are the strong Feller property and topological irreducibility, introduced in this work for a class of non-Markovian systems. They allow us to obtain a criteria for ergodicity which is similar in nature to the Doob

Saravanan Vijayakumaran

This submission is being withdrawn due to serious errors in the achievability proofs. The reviewers of the journal I had submitted to had found errors back in 2006. I had forgotten about this paper until I saw the CFP for a JSAC issue on in-network computation. http://www.jsac.ucsd.edu/Calls/in-networkcomputationcfp.pdf.

S. McNamara, H. J. Herrmann

Quasi-rigidity means that one builds a theory for assemblies of grains under a slowly changing external load by using the deformation of those grains as a small parameter. Is quasi-rigidity a complete theory for these granular assemblies? Does it provide unique predictions of the assembly&#39;s behavior, or must some other process be invoked to decide betwee

G. Aldazabal, E. Andres, J. E. Juknevich

As a further elaboration of the proposal of Ref. [1] we address the construction of Standard-like models from configurations of stacks of orientifold planes and D-branes on an internal space with the structure ${(Gepner model)^{c=6} \times T^2}/Z_N$. As a first step, the construction of D=6 Type II B orientifolds on Gepner points, in the diagonal invariant c

Mustafa Salti, Oktay Aydogdu

This paper has been removed by arXiv administrators because it plagiarizes gr-qc/0010068, gr-qc/9911018, gr-qc/0303034, and gr-qc/0212018.

Thomas Pietraho

We describe a relationship between Robinson-Schensted algorithms defined for standard domino tableaux of unequal rank. The principal idea is the moving-through operation defined on standard domino tableaux by D. Garfinkle. When restricted to involutions, this answers a question posed by M.A.A. van Leeuwen.

Filippo Caruso, Vittorio Giovannetti

The notion of weak-degradability of quantum channels is introduced by generalizing the degradability definition given by Devetak and Shor. Exploiting the unitary equivalence with beam-splitter/amplifier channels we then prove that a large class of one-mode Bosonic Gaussian channels are either weakly degradable or anti-degradable. In the latter case this impl

S. Kalyana Rama

We study a d-dimensional FRW universe, containing a perfect fluid with p = w ρand \frac{1} {d - 1} \le w \le 1, and find a correspondence principle similar to that of Horowitz and Polchinski in the black hole case. This principle follows quite generally from thermodynamics and the conservation of energy momentum tensor, and can be stated along similar lines

Anders Johansen, Hubert Klahr, Antony J. Mee

We study the effect of an imposed vertical magnetic field on the turbulent mass diffusion properties of magnetorotational turbulence in protoplanetary discs. It is well-known that the effective viscosity generated by the turbulence depends strongly on the magnitude of such an external field. In this letter we show that the turbulent diffusion of the flow als

Takayuki Ishino, Nobuyoshi Ohta

A large class of time-dependent solutions with 1/2 supersymmetry were found previously. These solutions involve cosmic singularities at early time. In this paper, we study if matrix string description of the singularities in these solutions with backgrounds is possible and present several examples where the solutions can be described well in the perturbative

Barbara Capone, Tommaso Castellani, Irene Giardina, Federico Ricci-Tersenghi

We study analytically the dynamics of a generalized p-spin model, starting with a thermalized initial condition. The model presents birth and death of states, hence the dynamics (even starting at equilibrium) may go out of equilibrium when the temperature is varied. We give a full description of this constrained out of equilibrium behavior and we clarify the

J. Viana Lopes, Miguel D. Costa, J. M. B. Lopes dos Santos, R. Toral

We propose a new recursive procedure to estimate the microcanonical density of states in multicanonical Monte Carlo simulations which relies only on measurements of moments of the energy distribution, avoiding entirely the need for energy histograms. This method yields directly a piecewise analytical approximation to the microcanonical inverse temperature, $

Fernando Rego Loup

We use the Conformal Metric as described in Kar-Sinha work on Gravitational Bending of Light in a 5D Spacetime to recompute the equations of the 5D Force in Basini-Capozziello-Leon Formalism and we arrive at a result that possesses some advantages. The equations of the Extra Force as proposed by Leon are now more elegant in Conformal Formalism and many algeb

Martin Konieczny, Christos N. Likos

We employ monomer-resolved Molecular Dynamics simulations and theoretical considerations to analyze the conformations of multiarm polyelectrolyte stars close to planar, uncharged walls. We identify three mechanisms that contribute to the emergence of a repulsive star-wall force, namely: the confinement of the counterions that are trapped in the star interior

Saharon Shelah

We to a large extent sort out when does a (first order complete theory) T have a superlimit model in a cardinal lambda . Also we deal with relation notions of being limit.

Shoichi Ichinose

A graphical representation of supersymmetry is presented. It clearly expresses the chiral flow appearing in SUSY quantities, by representing spinors by {\it directed lines} (arrows). The chiral suffixes are expressed by the directions (up, down, left, right) of the arrows. The SL(2,C) invariants are represented by {\it wedges}. Both the Weyl spinor and the M

Yu Shi, Qian Niu

We propose a practically accessible non-mean-field ground state of Bose-Einstein condensation (BEC), which occurs in an interspecies two-particle entangled state, and is thus described by an entangled order parameter. A suitably defined entanglement entropy is used as the characterization of the non-mean-field nature, and is found to persist in a wide parame

M. V. Ignatev, A. N. Panov

We present the classification of coadjoint orbits of the unitriangular group $UT(7, K)$. We also describe subregular orbits of $UT(n, K)$ for an arbitrary $n$.

Brien C. Nolan

The stability of naked singularities in self-similar collapse is probed using scalar waves. It is shown that the multipoles of a minimally coupled massless scalar field propagating on a spherically symmetric self-similar background spacetime admitting a naked singularity maintain finite $L^2$ norm as they impinge on the Cauchy horizon. It is also shown that

Rob Ivison

Bolometer arrays on large antennas at high, dry sites have unveiled a dusty population of massive, luminous galaxies - submillimetre galaxies, or SMGs - which make a significant contribution to the star-formation rate density at z > 1. The most crucial piece of information required to derive the history of obscured star formation is the redshift distribution

A. M. Zagoskin, S. Ashhab, J. R. Johansson, Franco Nori

The two-level systems (TLSs) naturally occurring in Josephson junctions constitute a major obstacle for the operation of superconducting phase qubits. Since these TLSs can possess remarkably long decoherence times, we show that such TLSs can themselves be used as qubits, allowing for a well controlled initialization, universal sets of quantum gates, and read