October 2006 arXiv papers — page 30

H. P. van Ditmarsch, B. P. Kooi

We give some semantic results for an epistemic logic incorporating dynamic operators to describe information changing events. Such events include epistemic changes, where agents become more informed about the non-changing state of the world, and ontic changes, wherein the world changes. The events are executed in information states that are modeled as pointe

David Eppstein

We show that the triangulations of a finite point set form a flip graph that can be embedded isometrically into a hypercube, if and only if the point set has no empty convex pentagon. Point sets of this type include convex subsets of lattices, points on two lines, and several other infinite families. As a consequence, flip distance in such point sets can be

Peter van Loock, Christian Weedbrook, Mile Gu

The linear optical creation of Gaussian cluster states, a potential resource for universal quantum computation, is investigated. We show that for any Gaussian cluster state, the canonical generation scheme in terms of QND-type interactions, can be entirely replaced by off-line squeezers and beam splitters. Moreover, we find that, in terms of squeezing resour

Caglar Tuncay

A quantitative method is suggested, where meanings of words, and grammatic rules about these, of a vocabulary are represented by real numbers. People meet randomly, and average their vocabularies if they are equal; otherwise they either copy from higher hierarchy or stay idle. Presence of teachers broadcasting the same (but arbitrarily chosen) vocabulary lea

Hailu Luo, Weixing Shu, Fei Li, Zhongzhou Ren

Based on boundary conditions and dispersion relations, the anomalous propagation of waves incident from regular isotropic media into quasiisotropic media is investigated. It is found that the anomalous negative refraction, anomalous total reflection and oblique total transmission can occur in the interface associated with quasiisotropic media. The Brewster a

B. S. Zou

The newest progress on the study of the strangeness in the proton and in the lowest negative parity nucleon excited state $N^*(1535)$ is reviewed. Implications on the internal quark structure of the proton, $N^*(1535)$ and other baryons are discussed. The diquark cluster picture for the 5-quark components in baryons gives a natural explanation not only to th

Ido Kanter, Noam Gross, Einat Klein, Evi Kopelowitz

Two mutually coupled chaotic diode lasers exhibit stable isochronal synchronization in the presence of self feedback. When the mutual communication between the lasers is discontinued by a shutter and the two uncoupled lasers are subject to self-feedback only, the desynchronization time is found to scale as $A_dτ$ where $A_d>1$ and $τ$ corresponds to the opti

Avinash Khare, Avadh Saxena

Coupled asymmetric double well ($aϕ^2-bϕ^3+cϕ^4$) one-dimensional potentials arise in the context of first order phase transitions both in condensed matter physics and field theory. Here we provide an exhaustive set of exact periodic solutions of such a coupled asymmetric model in terms of elliptic functions (domain wall arrays) and obtain single domain wall

Marcus Kollar

P(n,s) denotes the number of permutations of 1,2,...n that have exactly s sequences. Canfield and Wilf [math.CO/0609704] recently showed that P(n,s) can be written as a sum of s polynomials in n. We determine these polynomials explicitly and also obtain explicit expressions for P(n,s) and its fixed-s generating function u_s(x).

I. M. Anderson, M. E. Fels

We characterize Lie group actions for which there exists, at least locally, an evaluation map that defines a cochain map from the differential complex of invariant forms on a manifold to the De Rham complex for the quotient.

Rainer Weissauer

Torelli's theorem is proven by the study of the convolution product of the intersection cohomology sheaf of the thetadivisor.

Martin Charles Golumbic, Uri N. Peled, Udi Rotics

A triangle-free graph $G$ is called read-$k$ when there exists a monotone Boolean formula $ϕ$ whose variables are the vertices of $G$ and whose minterms are precisely the edges of $G$, such that no variable occurs more than $k$ times in $ϕ$. The smallest such $k$ is called the readability of $G$. We exhibit a very simple class of bipartite chain graphs on $2

Nicole Berline, Michele Vergne

We write the equivariant Todd class of a general complete toric variety as an explicit combination of the orbit closures, the coefficients being analytic functions on the Lie algebra of the torus which satisfy Danilov's requirement.

Raymond Hemmecke, Jason Morton, Anne Shiu, Bernd Sturmfels

Semigraphoids are combinatorial structures that arise in statistical learning theory. They are equivalent to convex rank tests and to polyhedral fans that coarsen the reflection arrangement of the symmetric group. We resolve two problems on semigraphoids posed in Studeny's book, and we answer a related question by Postnikov, Reiner, and Williams on gener

Shunsuke Teraguchi

We reformulate bosonic boundary string field theory in terms of boundary state. In our formulation, we can formally perform the integration of target space equations of motion for arbitrary field configurations without assuming decoupling of matter and ghost. Thus, we obtain the general form of the action of bosonic boundary string field theory. This formula

A. Mirjalili, K. Keshavarzian

We analysis the sea quark densities, based on the constituent quark model. To perform a direct fit with available experimental data, the parameterized Inverse Mellin technique is used. The calculation is extended to the NLO approximation for the singlet and non-singlet cases in DIS phenomena. We employ the approach of complete RG improvement(CORGI) where one

Abdesslam Arhrib, Rachid Benbrik, Bryan Field

The CP-odd Higgs boson $A^0$ of the Minimal Supersymmetric Standard Model (MSSM) and Two Higgs Doublet Model (2HDM) will usually decay into the heaviest possible fermion -- antifermion pair available. The $A^0 \to VV$ decay where, $V =γ, Z, W^\pm$, and gluons are of particular interest as they are not allowed at tree level and hence they may offer informatio

C. J. Maxwell

We consider the one-chain term in a skeleton expansion for Euclidean QCD observables. Focusing on the particular example of the Adler D function, we show that although there is a Landau pole in the coupling at Q^2=Λ^2 which renders fixed-order perturbative results infinite, the Landau pole is absent in the all-orders one-chain result. In this approximation o

M. Osipenko, S. Simula, S. Kulagin, G. Ricco

The experimental data on F2 structure functions of the proton and deuteron were used to construct their moments. In particular, recent measurements performed with CLAS detector at Jefferson Lab allowed to extend our knowledge of structure functions in the large-x region. The phenomenological analysis of these experimental moments in terms of the Operator Pro

D. A. Demir, Y. Farzan

In the framework of seesaw mechanism embedded in the constrained Minimal Supersymmetric Standard Model (cMSSM), phases of neutrino Yukawa coupling, $μ$-term and $A$-terms can all contribute to the Electric Dipole Moment (EDM) of the electron. We discuss and classify the situations for which by combined analysis of the upcoming results on $d_e$, $d_{\rm Hg}$

Stephen R. Sharpe

I give a status report on the validity of the so-called ``fourth-root trick'', i.e. the procedure of representing the determinant for a single fermion by the fourth root of the staggered fermion determinant. This has been used by the MILC collaboration to create a large ensemble of lattices using which many quantities of physical interest have been a

V. K. Petrov

It is shown that in asymptotic transition from Fourier series to integrals an error and ambiguity may arise. Ambiguity reduces to a possibility of addition of some distribution to the result. Properties of such distributions are studied and conditions are established under which ambiguity doesn't arise. Method for correction computation is suggested and

E. Follana, Q. Mason, C. Davies, K. Hornbostel

We use perturbative Symanzik improvement to create a new staggered-quark action (HISQ) that has greatly reduced one-loop taste-exchange errors, no tree-level order a^2 errors, and no tree-level order (am)^4 errors to leading order in the quark's velocity v/c. We demonstrate with simulations that the resulting action has taste-exchange interactions that a

Frank Grosse, Roland Zimmermann

The modification of acoustic phonons in semiconductor nanostructures embedded in a host crystal is investigated including corrections due to strain within continuum elasticity theory. Effective elastic constants are calculated employing {\em ab initio} density functional theory. For a spherical InAs quantum dot embedded in GaAs barrier material, the electron

J. S. Brown

We present further evidence for the coherent RDDI phase postulated in our earlier paper and clarify the reasons why the intersite tunnelling amplitude is increased by many orders of magnitude when a mesoscopic domain undergoes such a transition.

Christian Buth, Beate Paulus

Hydrogen bonding in infinite HF and HCl bent (zigzag) chains is studied using the ab initio coupled-cluster singles and doubles (CCSD) correlation method. The correlation contribution to the binding energy is decomposed in terms of nonadditive many-body interactions between the monomers in the chains, the so-called energy increments. Van der Waals constants

Amir Levinson

A GRMHD model of disk outflows with neutrino-driven mass ejection is presented. The model is used to calculate the structure of the outflow in the sub-slow magnetosonic region and the mass loading of the outflow, under conditions anticipated in the central engines of gamma-ray bursts. It is concluded that magnetic launching of ultra-relativistic polar outflo

C. Kramer, M. Hitschfeld, K. F. Schuster, S. Garcia-Burillo

The nearby, almost face-on, and interacting galaxy M51 offers an excellent opportunity to study the distribution of molecular gas and the mechanisms governing the star formation rate. We have created a complete map of M51 in 12CO 2-1 at a resolution of 11 arcsec corresponding to 450 kpc using HERA at the IRAM-30m telescope. In Schuster et al. (2006) we have

Vadim V. Bobylev

We have redetermined kinematic parameters of the Gould Belt using currently available data on the motion of nearby young (log t < 7.91) open clusters, OB associations, and moving stellar groups. Our modeling shows that the residual velocities reach their maximum values of -4 km/s for rotation (in the direction of Galactic rotation) and +4 km/s for expansion

Jianfeng Zhou, Yan Su

It is widely accepted that the Doppler deboosting effects exist in counter relativistic jets. However, people often neglect another important fact that both Doppler boosting and deboosting effects could happen in forward relativistic jets. Such effects might be used to explain some strange phenomena, such as the invisible gaps between the inner and outer jet

Kevin Ford

We give sharp, uniform estimates for the probability that a random walk of n steps on the reals avoids a half-line [y,infinity) given that it ends at the point x. The estimates hold for general continuous or lattice distributions provided the 4th moment is finite.

Dragan Huterer, Hiranya V. Peiris

We perform a comprehensive study of a class of dark energy models - scalar field models where the effective potential can be described by a polynomial series - exploring their dynamical behavior using the method of flow equations that has previously been applied to inflationary models. Using supernova, baryon oscillation, CMB and Hubble constant data, and an

Yiqiang Li

We investigate the affine canonical basis and the monomial basis constructed in [LXZ] in Lusztig&#39;s geometric setting. We show that the transition matrix between the two bases is upper triangular with 1&#39;s in the diagonal and coefficients in the upper diagonal entries in N[v, v^{-1}]. As a consequence, we show that part of the monomial basis elements g

Bruno Kahn

We study the multiplicities of pure motives modulo numerical equivalence, which are defined as scalars comparing the tannakian trace with the ring-theoretic trace. Our general set-up is that of a rigid semi-simple tensor category such that End(1) is a field of characteristic 0. The main result is that, due to the existence of a Weil cohomology theory (to be

R. Mansilla, E. Köppen, G. Cocho, P. Miramontes

An empirical law for the rank-order behavior of journal impact factors is found. Using an extensive data base on impact factors including journals on Education, Agrosciences, Geosciences, Biosciences and Environ- mental, Chemical, Computer, Engineering, Material, Mathematical, Medical and Physical Sciences we have found extremely good fits out- performing ot

David Emmanuel-Costa, Pavel Fileviez Perez, Ricardo Gonzalez Felipe

The possibility to achieve unification at the string scale in the context of the simplest supersymmetric grand unified theory is investigated. We find conservative upper bounds on the superpartner masses consistent with the unification of gauge and gravitational couplings, M_{\tilde G} < 5 TeV and M_{\tilde f} < 3 \times 10^7 GeV, for the superparticles with

Wan-lei Guo

We investigate the lepton flavor violating (LFV) rare decays in the supersymmetric minimal seesaw model in which the Frampton-Glashow-Yanagida ansatz is incorporated. The branching ratio of $μ\to e γ$ is calculated in terms of the Snowmass Points and Slopes (SPS). We find that the inverted mass hierarchy is disfavored by all SPS points. In addition, once the

Ali N. Khorramian, S. Atashbar Tehrani

We use the next-to-next-to-leading order (NNLO) contributions to anomalous dimension governing the evolution of non-singlet quark distributions. We use the xF3 data of the CCFR collaboration to obtain some unknown parameters which exist in the non-singlet quark distributions in the NNLO approximation. In the fitting procedure, Bernstein polynomial method is

Zhi-Gang Wang

In this article, we take the point of view that Y(2175) be a tetraquark state which consists of color octet constituents, and calculate its mass and decay constant within the framework of the QCD sum rule approach. We release standard criterion in the QCD sum rules approach and take more phenomenological analysis, the value of the mass of Y(2175) is consiste

M. Modarres, M. M. Yazdanpanah

The charm quark structure function $F^c_2$ and the longitudinal structure function $F_l^p$ are directly sensitive to the gluon content of proton and therefore are crucial in understanding of proton structure function, in particular at low momentum transfer $Q^2$ and low Bjorken x. In the framework of perturbative QCD the charm structure function is calculate

Efstratia Kalfagianni

We prove the nugatory crossing conjecture for fibered knots. We also show that if a knot $K$ is $n$-adjacent to a fibered knot $K&#39;$, for some $n>1$, then either the genus of $K$ is larger than that of $K&#39;$ or $K$ is isotopic to $K&#39;$.

Guo-meng Zhao

The spectra of the second derivative of tunneling current d^{2}I/dV^{2} in the high-temperature superconductors YBa_{2}Cu_{3}O_{7-δ} and Bi_{2}Sr_{2}CaCu_{2}O_{8+δ} show clear dip and peak features due to strong coupling to the bosonic modes mediating electron pairing. The energies of all the peaks in -d^{2}I/dV^{2}-like spectra match precisely with the ener

M. I. Dyakonov

The so-called &#34;threshold&#34; theorem says that, once the error rate per qubit per gate is below a certain value, indefinitely long quantum computation becomes feasible, even if all of the qubits involved are subject to relaxation processes, and all the manipulations with qubits are not exact. The purpose of this article, intended for physicists, is to o

Biplab Ghosh, A. S. Majumdar, N. Nayak

We consider first a system of two enatangled cavities and a single two-level atom passing through one of them. A ``monogamy&#39;&#39; inequality for this tripartite system is quantitatively studied and verified in the presence of cavity leakage. We next consider the simultaneous passage of two-level atoms through both the cavities. Entanglement swapping is o

Victor Javier Charette, Elisa Evangelista, Ricardo Chertcoff, Harold Auradou

Tracer dispersion is studied experimentally in periodic or disordered arrays of beads in a capillary tube. Dispersion is measured from light absorption variations near the outlet following a steplike injection of dye at the inlet. Visualizations using dye and pure glycerol are also performed in similar geometries. Taylor dispersion is dominant both in an emp

M. V. Stoitsov, J. Dobaczewski, R. Kirchner, W. Nazarewicz

Variation after particle-number restoration is incorporated for the first time into the Hartree-Fock-Bogoliubov framework employing the Skyrme energy density functional with zero-range pairing. The resulting projected HFB equations can be expressed in terms of the local gauge-angle-dependent densities. Results of projected calculations are compared with thos

Tadafumi Ohsaku

The relation between the Moyal-Weyl deformation quantization and quasiconformal mappings of Riemann surfaces of complex analysis are shown by several examples.

Yiqiang Li, Zongzhu Lin

We construct the entire generalized Kac-Moody Lie algebra as a quotient of the positive part of another generalized Kac-Moody Lie algebra. The positive part of a generalized Kac-Moody Lie algebra can be constructed from representations of quivers using Ringel&#39;s Hall algebra construction. Thus we give a direct realization of the entire generalized Kac-Moo

Yiqiang Li, Zongzhu Lin

Let U be the quantum group associated to a symmetrizable generalized Cartan matrix. We give a realization of U from the category of the representations of certain product valued quiver.

H. Abels M. Kassmann

We consider the linear integro-differential operator $L$ defined by \[ Lu(x) =\int_\Rn (u(x+y) - u(x) - 1_{[1,2]}(α) 1_{\{|y|\leq 2\}}(y)y \cdot \nabla u(x)) k(x,y) \sd y . \] Here the kernel $k(x,y)$ behaves like $|y|^{-d-α}$, $α\in (0,2)$, for small $y$ and is Hölder-continuous in the first variable, precise definitions are given below. The aim of this wor

Yu Zou, Ioannis G. Kevrekidis

We describe a computational framework linking Uncertainty Quantification (UQ) methods for continuum problems depending on random parameters with Equation-Free (EF) methods for performing continuum deterministic numerics by acting directly on atomistic/stochastic simulators. Our illustrative example is a heterogeneous catalytic reaction mechanism with an unce

Bau-Sen Du

In their celebrated &#34;Period three implies chaos&#34; paper, Li and Yorke proved that if a continuous interval map f has a period 3 point then there is an uncountable scrambled set S on which f has very complicated dynamics. One question arises naturally: Can this set S be chosen invariant under f? The answer is positive for turbulent maps and negative ot

Jean Bertoin

It was shown recently that a Langevin process can be reflected at an energy absorbing boundary. Here, we establish that the law of this reflecting process can be characterized as the unique weak solution to a certain second order stochastic differential equation with constraints, which is in sharp contrast with a deterministic analog.

Mircea Cimpoeas

In this paper, we introduce a new class of monomial ideals, called $d$-fixed ideals, which generalize the class of $p$-Borel ideals and show how some results for $p$-Borel ideals can be transfered to this new class. In particular, we give the form of a principal $d$-fixed ideal and we compute the socle of factors of these ideals. This allowed us to give a ge

Reuven Segev

For the stress analysis in a plastic body $Ω$, we prove that there exists a maximal positive number $C$, the \emph{load capacity ratio,} such that the body will not collapse under any external traction field $t$ bounded by $Y_{0}C$, where $Y_0$ is the elastic limit. The load capacity ratio depends only on the geometry of the body and is given by $$ \frac{1}{

Ilya L. Shapiro

The purpose of this article is to present a short review of local conformal symmetry in curved 4d space-time. Furthermore we discuss the conformal anomaly and anomaly-induced effective actions. Despite the conformal symmetry is always broken at quantum level, it may be a basis of useful and interesting approximations for investigating quantum corrections.

V. D. Ivashchuk, V. N. Melnikov, D. Singleton

In this paper we generalize electric S-brane solutions with maximal number of branes. Previously for the action containing D-dimensional gravity, a scalar field and antisymmetric (p+2)-form we found composite, electric S-brane solutions with all non-zero ``charge&#39;&#39; densities which obeyed self-duality or anti-self-duality relations. These solutions oc

Athanasios Prikas

We study domain-wall networks on the surface of q-stars in asymptotically flat or anti de Sitter spacetime. We provide numerical solutions for the whole phase space of the stable field configurations and find that the mass, radius and particle number of the star is larger but the scalar field, responsible for the formation of the soliton, acquires smaller va

Athanasios Prikas

We present Jordan-Brans-Dicke and general scalar-tensor gravitational theory in extra dimensions in an asymptotically flat or anti de Sitter spacetime. We consider a special gravitating, boson field configuration, a $q$-star, in 3, 4, 5 and 6 dimensions, within the framework of the above gravitational theory and find that the parameters of the stable stars a

Shin&#39;ichi Nojiri, Sergei D. Odintsov

The reconstruction scheme is developed for modified $f(R)$ gravity with realistic matter (dark matter, baryons, radiation). Two versions of such theory are constructed: the first one describes the sequence of radiation and matter domination, decceleration-acceleration transition and acceleration era and the second one is reconstructed from exact Lambda-CDM c

Rouzbeh Allahverdi

We argue that all necessary ingredients for successful inflation are present in the flat directions of the minimal supersymmetric standard model (MSSM). Out of many gauge invariant combinations of the squarks, sleptons and Higgses, there are two flat directions, ${\bf LLe}$, and ${\bf udd}$, which are promising candidates for the inflaton. The model predicts

Roberto Casalbuoni

We review the history of the critical point in the QCD phase diagram, baryon density vs. temperature. In particular we discuss the different theoretical approaches to this problem.

I. V. Anikin, B. Pire, L. Szymanowski, O. V. Teryaev

The QCD analysis of the recent experimental data (L3@LEP) of the hard exclusive $ρρ$ production in two photon collisions shows that these data can be understood as a signal for the existence of an exotic isotensor resonance with a mass around $1.5 {\rm GeV}$. We also argue that hard exclusive reactions are a powerful tool for an experimental study of exotic

Lei Chang, Yu-xin Liu

We study the consistency of the ladder approximation and the rainbow approximation of the Dyson-Schwinger equation of QCD. By considering the non-Abelian property of QCD, we show that the QED-type Ward-Takahashi identity is not required for the rainbow-ladder approximation of QCD. It indicates that there does not exists any internal inconsistency in the usua

Mehrdad Ghominejad, Hossein Mehraban

In this research we describe effective Hamiltonian theory and apply this theory to the calculation of current-current $Q_{12}$ and QCD penguin $Q_{3...6}$ decay rates We calculate the decay rates of semileptonic and hadronic of charm quark in effective Hamiltonian theory. We investigate the decay rates of D meson decays according to Spectator Quark Model(SQM

M. Engelhardt, B. Sperisen

A random vortex world-surface model for the infrared sector of Sp(2) Yang-Mills theory is constructed. The Sp(2) gauge group, while allowing for the same set of center vortex fluxes as the SU(2) gauge group, induces a significantly different dynamics on those vortex fluxes, which manifests itself in a first-order deconfinement phase transition. As shown by t

Abdou M. Abdel-Rehim, Randy Lewis, R. M. Woloshyn, Jackson M. S. Wu

There are three quarks with masses at or below the characteristic scale of QCD dynamics: up, down and strange. However, twisted mass lattice QCD relies on quark doublets. Various options for including three quark flavors within the twisted mass approach are explored by studying the kaon masses, both analytically (through chiral Lagrangians) and numerically (

Daniel Wicke

With its discovery in 1995 by the CDF and D0 collaborations the top quark completed the set of quarks expected by the Standard Model. It is predicted to have the same quantum numbers and couplings as the other up-type quarks. Albeit, only very few of these properties have been verified so far. This article summarises the existing measurements of top quark pr

B. Sciascia

At present, the main topics addressed by kaon physics are the unitarity test of CKM matrix via precision measurements of the Cabibbo angle as well as precision tests of discrete symmetries: in particular, study of possible CPT violations in a model-independent way through the Bell-Steinberger relation, or through the measurement of charge asymmetries. Other

Mihalis Dafermos, Alan D. Rendall

We prove strong cosmic censorship for T^2-symmetric cosmological spacetimes (with spatial topology T^3 and vanishing cosmological constant Lambda) with collisionless matter. Gowdy symmetric spacetimes constitute a special case. The formulation of the conjecture is in terms of generic C^2-inextendibility of the metric. Our argument exploits a rigidity propert

Leonardo Modesto

In this paper we study the gravitational collapse in loop quantum gravity. We consider the space-time region inside the Schwarzschild black hole event horizon and we divide this region in two parts, the first one where the matter (dust matter) is localized and the other (outside) where the metric is Kantowski-Sachs type. We calculate the state solving Hamilt

Himanshu Thapliyal, Hamid R. Arabnia, A. P Vinod

In this paper, the authors propose the idea of a combined integer and floating point multiplier(CIFM) for FPGAs. The authors propose the replacement of existing 18x18 dedicated multipliers in FPGAs with dedicated 24x24 multipliers designed with small 4x4 bit multipliers. It is also proposed that for every dedicated 24x24 bit multiplier block designed with 4x

Himanshu Thapliyal, Mark Zwolinski

Differential Power Analysis (DPA) presents a major challenge to mathematically-secure cryptographic protocols. Attackers can break the encryption by measuring the energy consumed in the working digital circuit. To prevent this type of attack, this paper proposes the use of reversible logic for designing the ALU of a cryptosystem. Ideally, reversible circuits

A. Sparavigna, B. Montrucchio

We have recently developed an algorithm for vector field visualization with oriented streamlines, able to depict the flow directions everywhere in a dense vector field and the sense of the local orientations. The algorithm has useful applications in the visualization of the director field in nematic liquid crystals. Here we propose an improvement of the algo

G. M. Schmiedeshoff, A. W. Lounsbury, D. J. Luna, S. J. Tracy

We describe the design, construction, calibration, and operation of a relatively simple differential capacitive dilatometer suitable for measurements of thermal expansion and magnetostriction from 300 K to below 1 K with a low-temperature resolution of about 0.05 angstroms. The design is characterized by an open architecture permitting measurements on small

Magnus N. J. Bergroth, Sharon C. Glotzer

By molecular dynamics (MD) simulation of the one-component Dzugutov liquid in a metastable equilibrium supercooled state approaching the glass transition, we investigate the structural properties of highly mobile particles moving in strings at low temperature T where string-like particle motion (SLM) is well developed. We find that SLM occurs most frequently

J. Hecker Denschlag, A. J. Daley

We review a recent experiment with ultracold atoms in 3D optical lattices where we have observed a novel kind of bound state of two atoms which is based on repulsive interactions between the particles. These repulsively bound pairs exhibit long lifetimes, even under conditions when they collide with one another. Stable repulsively bound objects should be vie

James M. Knight, Milind N. Kunchur

At high dissipation levels, vortex motion in a superconducting film has been observed to become unstable at a certain critical vortex velocity v*. At substrate temperatures substantially below Tc, the observed behavior can be accounted for by a model in which the electrons reach an elevated temperature relative to the phonons and the substrate. Here we exami

Aftab Alam, Subhradip Ghosh, Abhijit Mookerjee

A first principles density functional based linear response theory (the so called Density Functional Perturbation theory \cite{dfpt}) has been combined separately with two recently developed formalism for a systematic study of the lattice dynamics in disordered binary alloys. The two formalisms are the Augmented space recursion (ASR) and the Itinerant cohere

V. Ya. Demikhovskii, F. M. Izrailev, A. I. Malyshev

We study the electron dynamics in a 2D waveguide bounded by a periodically rippled surface in the presence of the time-periodic electric field. The main attention is paid to a possibility of a weak quantum diffusion along the coupling resonance, that can be associated with the classical Arnol&#39;d diffusion. It was found that quantum diffusion is possible o

Manabu Kiguchi, Shinichi Miura, Kenji Hara, Masaya Sawamura

The effect of anchoring group on the electrical conductance of a single molecule bridging two Au electrodes was studied using di-substituted (isocyanide (CN-), thiol (S-) or cyanide (NC-)) benzene. The conductance of a single Au/1,4-diisocyanobenzene/Au junction anchored by isocyanide via a C atom (junction with the Au-CN bond) was $3 \times 10 ^{-3} G_{0}$

F. M. Izrailev, A. A. Krokhin, N. M. Makarov, S. S. Melnyk

We study properties of the additive binary Markov chain with short and long-range correlations. A new approach is suggested that allows one to express global statistical properties of a binary chain in terms of the so-called memory function. The latter is directly connected with the pair correlator of a chain via the integral equation that is analyzed in gre

Bin Chen, Zhenyue Zhu, X. C. Xie

By using multi-bands BCS theory, we have calculated the superconductivity energy gap and the critical temperature of a thin-film metallic superconductor. The thermodynamic superconducting characteristics such as critical magnetic field, specific heat, as well as the tunneling conductance are investigated for varying film thickness and temperature. We find th

P. -O. Quirion, G. Fontaine, P. Brassard

We derive the theoretical red edge of the pulsating GW Vir stars by using full evolutionary calculations that involve mass loss and diffusion. We put the emphasis on the fact that the specific mass loss law used in the evolutionary computations determines the red edge&#39;s position. By combining this specific property with the observed location of the red e

I. I. Agafonova, S. A. Levshakov, D. Reimers, C. Fechner

The shape of the UV ionizing background is reconstructed from optically thin metal absorption-line systems identified in spectra of HE2347-4342, Q1157+3143, and HS1700+6416 in the redshift interval 1.8 < z < 2.9. The systems are analyzed by means of the Monte Carlo Inversion method completed with the spectral shape recovering procedure. The UVB spectral shap

S. Hubrig, M. A. Pogodin, R. V. Yudin, M. Schoeller

We intend to investigate separately the photospheric and circumstellar (CS) magnetic field components in seven Herbig Ae stars. The study is based on low-resolution (R ~ 2000 and 4000) spectropolarimetric data collected from 2003 to 2005 at the Very Large Telescope (ESO, Chile) with the multi-mode instrument FORS1. We show that the spectropolarimetric result

Wei Zhang, Xu Kong, Cheng Li, Hong-yan Zhou

We use a large sample of 174 Wolf-Rayet (WR) galaxies drawn from the Sloan Digital Sky Survey to study whether and how the slope of the stellar initial mass function depends on metallicity. We calculate for each object its oxygen abundance according to which we divide our sample into four metallicity subsamples. For each subsample, we then measure three quan

J. D. Monnier, P. G. Tuthill, W. C. Danchi, N. Murphy

We report the results of a high angular resolution near-infrared survey of dusty Wolf-Rayet stars using the Keck-1 Telescope, including new multi-wavelength images of the pinwheel nebulae WR 98a, WR 104, and WR 112. Angular sizes were measured for an additional 8 dusty WR stars using aperture masking interferometry, allowing us to probe characteristics sizes

Juergen Appel, Dallas Hoffman, Eden Figueroa, A. I. Lvovsky

The effect of the detector electronic noise in an optical homodyne tomography experiment is shown to be equivalent to an optical loss if the detector is calibrated by measuring the quadrature noise of the vacuum state. An explicit relation between the electronic noise level and the equivalent optical efficiency is obtained and confirmed in an experiment with

A. S. Erickson, S. Misra, G. J. Miller, R. R. Gupta

Results are presented of single crystal structural, thermodynamic, and reflectivity measurements of the double-perovskite Ba2NaOsO6. These characterize the material as a 5d^1 ferromagnetic Mott insulator with an ordered moment of ~0.2 Bohr magnetons per formula unit and TC = 6.8(3) K. The magnetic entropy associated with this phase transition is close to Rln

Dev Sinha, Ben Walter

We develop a new, intrinsic, computationally friendly approach to Lie coalgebras through graph coalgebras, which are new and likely to be of independent interest. Our graph coalgebraic approach has advantages both in finding relations between coalgebra elements and in having explicit models for linear dualities. As a result, proofs in the realm of Lie coalge

Moataz H. Emam

We study the dimensional reduction of M5-branes wrapping special Lagrangian 3-cycles of a Calabi-Yau manifold and show explicitly that they result in 2-branes coupled to the hypermultiplets of ungauged N=2 D=5 supergravity theory. In addition to confirming previously known results, the calculation proves the relationship between them and provides further ins

Shu Lin, Edward Shuryak

In the context of the AdS/CFT correspondence we discuss the gravity dual of a high energy collision in a strongly coupled ${\cal N}=4$ SYM gauge theory. We suggest a setting in which two colliding objects are made of non-dynamical heavy quarks and antiquarks, which allows to treat the process in classical string approximation. Collision ``debris&#39;&#39; co

John Cardy

We point out that the probability law of a single domain wall separating clusters in ADE lattice models in a simply connected domain is identical to that of corresponding chordal curves in the lattice O(n) and Q-state Potts models, for suitable n or Q. They are conjectured to be described in the scaling limit by chordal SLE(kappa) with kappa rational and >2.

Clayton Heller, Isaac Shlosman, Lia Athanassoula

We investigate the formation and evolution of nested bar systems in disk galaxies in a cosmological setting by following the development of an isolated dark matter (DM) and baryon density perturbation. The disks form within the assembling triaxial DM halos and the feedback from the stellar evolution is accounted for in terms of supernovae and OB stellar wind

Nathan Roche

We investigate Arp 295, a pair of interacting spirals at z=0.023. We measure scalelengths 5.24 kpc for Arp 295a and 2.52 kpc for 295b. There is a much smaller Im galaxy associated with the larger spiral. Arp 295b is asymmetric with the disk more extended eastwards but with the brightest star-formation regions on the west side of the nucleus. The spectrum of

L. Hormozi, G. Zikos, N. E. Bonesteel, S. H. Simon

A method for compiling quantum algorithms into specific braiding patterns for non-Abelian quasiparticles described by the so-called Fibonacci anyon model is developed. The method is based on the observation that a universal set of quantum gates acting on qubits encoded using triplets of these quasiparticles can be built entirely out of three-stranded braids

Ken D. Olum, Vitaly Vanchurin

We study the production of loops in the cosmic string network in the expanding background by means of a numerical simulation exact in the flat-spacetime limit and first-order in the expansion rate. We find an initial regime characterized by production of small loops at the scale of the initial correlation length, but later we see the emergence of a scaling r

Kai-Yeung Lau, Surya Ganguli, Chao Tang

We develop a general method to explore how the function performed by a biological network can constrain both its structural and dynamical network properties. This approach is orthogonal to prior studies which examine the functional consequences of a given structural feature, for example a scale free architecture. A key step is to construct an algorithm that

S. A. Fenner, Y. Zhang

We show that several problems that figure prominently in quantum computing, including Hidden Coset, Hidden Shift, and Orbit Coset, are equivalent or reducible to Hidden Subgroup for a large variety of groups. We also show that, over permutation groups, the decision version and search version of Hidden Subgroup are polynomial-time equivalent. For Hidden Subgr