September 2009 arXiv papers — page 40

J. G. Checkelsky, Y. S. Hor, M. -H. Liu, D. -X. Qu

Photoemission experiments have shown that Bi$_2$Se$_3$ is a topological insulator. By controlled doping, we have obtained crystals of Bi$_2$Se$_3$ with non-metallic conduction. At low temperatures, we uncover a novel type of magnetofingerprint signal which involves the spin degrees of freedom. Given the mm-sized crystals, the observed amplitude is 200-500$\t

Michela Artebani, Antonio Laface

In this paper we investigate the relation between the finite generation of the Cox ring R(X) of a smooth projective surface X and its anticanonical Iitaka dimension k(-K_X).

P. V. Buividovich, M. N. Chernodub, E. V. Luschevskaya, M. I. Polikarpov

Vacuum of Quantum Chromodynamics in very strong (hadron-scale) magnetic fields exhibits many interesting nonperturbative effects. Some of these effects can be studied with the help of lattice simulations in quenched QCD. We review our recent results demonstrating that very strong external magnetic fields lead to (1) the enhancement of the chiral symmetry bre

Dorival Leão, Alberto Ohashi

In this paper we introduce a simple space-filtration discretization scheme on Wiener space which allows us to study weak decompositions and smooth explicit approximations for a large class of Wiener functionals. We show that any Wiener functional has an underlying robust semimartingale skeleton which under mild conditions converges to it. The discretization

C. T. Boone, J. A. Katine, M. Carey, J. R. Childress

We study domain wall (DW) dynamics in permalloy nanowires excited by alternating spin-polarized current applied perpendicular to the nanowire. Spin torque ferromagnetic resonance measurements reveal that DW oscillations at a pinning site in the nanowire can be excited with velocities as high as 800 m/s at current densities below 10$^7$ A/cm$^2$.

Michael J. Bommarito, Daniel Martin Katz, Jon Zelner, James H. Fowler

Acyclic digraphs arise in many natural and artificial processes. Among the broader set, dynamic citation networks represent a substantively important form of acyclic digraphs. For example, the study of such networks includes the spread of ideas through academic citations, the spread of innovation through patent citations, and the development of precedent in

Frederic Bournaud

A number of theoretical and simulation results on star and structure formation in galaxy interactions and mergers is reviewed, and recent hydrodynamic simulations are presented. The role of gravity torques and ISM turbulence in galaxy interactions, in addition to the tidal field, is highlighted. Interactions can drive gas inflows towards the central kpc and

Ross Fadely, Charles R. Keeton, Reiko Nakajima, Gary M. Bernstein

We present a detailed strong lensing analysis of an HST/ACS legacy dataset for the first gravitational lens, Q0957+561. With deep imaging we identify 24 new strongly lensed features, which we use to constrain mass models. We model the stellar component of the lens galaxy using the observed luminosity distribution, and the dark matter halo using several diffe

A. Maier, L. Iapichino, W. Schmidt, J. C. Niemeyer

We present a numerical scheme for modelling unresolved turbulence in cosmological adaptive mesh refinement codes. As a first application, we study the evolution of turbulence in the intra-cluster medium and in the core of a galaxy cluster. Simulations with and without subgrid scale model are compared in detail. Since the flow in the ICM is subsonic, the glob

Jonas A. Kjäll, Andrew M. Essin, Joel E. Moore

Several new features arise in the ground-state phase diagram of a spin-1 condensate trapped in an optical trap when the magnetic dipole interaction between the atoms is taken into account along with confinement and spin precession. The boundaries between the regions of ferromagnetic and polar phases move as the dipole strength is varied and the ferromagnetic

Emmanouil Chatzopoulos, J. Craig Wheeler, Jozsef Vinko

We consider simple models based on core collapse or pair-formation supernovae to account for the light curve of the transient SCP06F6. A radioactive decay diffusion model provides estimates of the mass of the required radioactive nickel and the ejecta as functions of the unknown redshift. An opacity change such as by dust formation or a recombination front m

Paul E. Grabowski, David F. Chernoff

We study the numerical solution of the non-relativistic Schrödinger equation for two-electron atoms in ground and excited S-states using pseudospectral (PS) methods of calculation. The calculation achieves convergence rates for the energy, Cauchy error in the wavefunction, and variance in local energy that are exponentially fast for all practical purposes. T

Maarit J. Korpi, Petri J. Käpylä, Miikka S. Väisälä

In this paper we make an effort to understand the interaction of turbulence generated by the magnetorotational instability (MRI) with turbulence from other sources, such as supernova explosions (SNe) in galactic disks. First we perform a linear stability analysis (LSA) of non-ideal MRI to derive the limiting value of Ohmic diffusion that is needed to inhibit

Emanuel Gull, Olivier Parcollet, Philipp Werner, Andrew J. Millis

We explore the momentum-sector-selective metal insulator transitions recently found in the eight - site dynamical cluster approximation to the two-dimensional Hubbard model. The phase diagram in the space of interaction and second-neighbor hopping is established. The initial transitions from Fermi-liquid like to sector-selective phases are found to be of sec

Alex S. Miranda, C. A. Ballon Bayona, Henrique Boschi-Filho, Nelson R. F. Braga

We use the holographic AdS/QCD soft-wall model to investigate the spectrum of scalar glueballs in a finite temperature plasma. In this model, glueballs are described by a massless scalar field in an AdS_5 black hole with a dilaton soft-wall background. Using AdS/CFT prescriptions, we compute the boundary retarded Green's function. The corresponding thermal s

Abdelhamid Albaid

A SUSY SO(10) $\times A_4$ GUT model is constructed for fermion masses and mixing by introducing a minimal set of low dimensional Higgs representations needed to break the guage symmetry down to $SU(3)_c \times U(1)_{em}$. The hierarchy of fermion masses can be understood in the framework of $A_4$ symmetry. From the $A_4$-invariant superpotential, the "d

Joachim A. Fuerst, Mads Brandbyge, Antti-Pekka Jauho

An atomic carbon chain joining two graphene flakes was recently realized in a ground-breaking experiment by Jin {\it et al.}, Phys. Rev. Lett. {\bf 102}, 205501 (2009). We present {\it ab initio} results for the electron transport properties of such chains and demonstrate complete spin-polarization of the transmission in large energy ranges. The effect is du

Alfredo Aranda, J. Lorenzo Diaz-Cruz, Ernest Ma, Roberto Noriega

The asymmetric Higgs sector of one $SU(2)_L \times SU(2)_R$ bidoublet $(\phi_1^0,\phi_1^-;\phi_2^+,\phi_2^0)$ and one $SU(2)_R$ doublet [but no $SU(2)_L$ doublet] is considered in a nonsupersymmetric left-right extension of the standard model (SM) of particle interactions. The inverse seesaw mechanism for neutrino mass is naturally implemented with the addit

Stefano Actis, Pierpaolo Mastrolia, Giovanni Ossola

In this paper we present a numerical implementation of the one-loop QED corrections to the hard-bremsstrahlung process e- e+ \to e- e+ gamma. These corrections can be included in the Monte Carlo event generators employed for simulating Bhabha scattering events at low-energy high-luminosity electron-positron colliders. The calculation is performed by employin

J. S. Lee, Y. Peters, A. Pilaftsis, C. Schwanenberger

We suggest a new CPX-derived scenario for the search of strangephilic MSSM Higgs bosons at the Tevatron and the LHC, in which all neutral and charged Higgs bosons decay predominantly into pairs of strange quarks and into a strange and a charm quark, respectively. The proposed scenario is realized within a particular region of the MSSM parameter space and req

QUaD collaboration, S. Gupta, P. Ade, J. Bock

We evaluate the contribution of cosmic microwave background (CMB) polarization spectra to cosmological parameter constraints. We produce cosmological parameters using high-quality CMB polarization data from the ground-based QUaD experiment and demonstrate for the majority of parameters that there is significant improvement on the constraints obtained from sa

Igor R. Klebanov, Giuseppe Torri

These notes provide a brief introduction to the ABJM theory, the level k U(N) x U(N) superconformal Chern-Simons matter theory which has been conjectured to describe N coincident M2-branes. We discuss its dual formulation in terms of M-theory on AdS_4 x S^7/Z_k and review some of the evidence in favor of the conjecture. We end with a brief discussion of the

Tiago P. Peixoto

We consider the effect of noise in sparse Boolean Networks with redundant functions. We show that they always exhibit a non-zero error level, and the dynamics undergoes a phase transition from non-ergodicity to ergodicity, as a function of noise, after which the system is no longer capable of preserving a memory if its initial state. We obtain upper-bounds o

G. N. Throumoulopoulos, H. Tasso

Two-dimensional Maxwell-Vlasov equilibria with finite electric fields, axial ("toroidal") plasma flow and isotropic pressure are constructed in plane geometry by using the quasineutrality condition to express the electrostatic potential in terms of the vector potential. Then for Harris-type distribution functions, Ampere's equation becomes of Lio

Kimitake Hayasaki, Keitaro Takahashi, Yuuiti Sendouda, Shigehiro Nagataki

We propose a new scenario for the evolution of a binary of primordial black holes (PBHs). We consider a dynamical friction by ambient dark matter, scattering of dark matter particles with a highly eccentric orbit besides the standard two-body relaxation process to refill the loss cone, and interaction between the binary and a circumbinary disk, assuming that

Kiril Hristov, Hugo Looyestijn, Stefan Vandoren

We determine and analyze maximally supersymmetric configurations in four-dimensional gauged N=2 supergravity, preserving eight supercharges. These models include arbitrary electric gaugings in the vector- and hypermultiplet sectors. We present several examples of such solutions and connect some of them to vacuum solutions of flux compactifications in string

Nils A. Baas, Bjorn Ian Dundas, Birgit Richter, John Rognes

The point of this paper is to prove the conjecture that virtual 2-vector bundles are classified by K(ku), the algebraic K-theory of topological K-theory. Hence, by the work of Ausoni and the fourth author, virtual 2-vector bundles give us a geometric cohomology theory of the same telescopic complexity as elliptic cohomology. The main technical step is showin

J. Tang, S. Scellato, M. Musolesi, C. Mascolo

Connections in complex networks are inherently fluctuating over time and exhibit more dimensionality than analysis based on standard static graph measures can capture. Here, we introduce the concepts of temporal paths and distance in time-varying graphs. We define as temporal small world a time-varying graph in which the links are highly clustered in time, y

Stephen Appleby, Richard Battye, Alexei Starobinsky

We study $F(R)$ modified gravity models which are capable of driving the accelerating epoch of the Universe at the present time whilst not destroying the standard Big Bang and inflationary cosmology. Recent studies have shown that a weak curvature singularity with $|R|\to\infty$ can arise generically in viable $F(R)$ models of present dark energy (DE) signal

The STAR Collaboration, B. I. Abelev

Parity-odd domains, corresponding to non-trivial topological solutions of the QCD vacuum, might be created during relativistic heavy ion collisions. These domains are predicted to lead to charge separation of quarks along the system's orbital momentum axis. We investigate a three particle azimuthal correlator which is a ¶even observable, but directly sen

J. Buschbeck, I. Opahle, M. Richter, U. K. Rossler

Huge deformations of the crystal lattice can be achieved in materials with inherent structural instability by epitaxial straining. By coherent growth on seven different substrates the in-plane lattice constants of 50 nm thick Fe70Pd30 films are continuously varied. The maximum epitaxial strain reaches 8,3 % relative to the fcc lattice. The in-plane lattice s

Ingrid Bauer, Fabrizio Catanese

Using a new description of Keum Naie surfaces and their fundamental group, we prove the following main result: Let S be a smooth complex projective surface which is homotopically equivalent to a Keum - Naie surface. Then S is a Keum - Naie surface. The connected component of the Gieseker moduli space corresponding to Keum - Naie surfaces is irreducible, norm

O. Tieleman, A. Lazarides, D. Makogon, C. Morais Smith

We investigate two theoretical pseudomagnon-based models for a bilayer quantum Hall system (BQHS) at total filling factor $\nu_t = 1$. We find a unifying framework which elucidates the different approximations that are made. We also consider the effect of an in-plane magnetic field in BQHSs at $\nu_t = 1$, by deriving an equation for the ground state energy

L. Gao, Tom Theuns, C. S. Frenk, A. Jenkins

We have implemented a simple model to identify the likely sites of the first stars and galaxies in the high-resolution simulations of the formation of galactic dark matter halos of the Aquarius Project. The first star in a galaxy like the Milky Way formed around redshift z=35; by z=10, the young galaxy contained up to 30000 dark matter haloes capable of form

Serban Misicu, Florin Carstoiu

The ground state energy of ideal alpha-matter at T=0 is analyzed within the framework of variational theory of Bose quantum liquids. Calculations are done for three local alpha-alpha potentials with positive volume integrals and two-body correlation functions obtained from the Pandharipande-Bethe equation. The energy per particle of $\alp$ matter is evaluate

Osvaldo P. Santillan

A method for constructing explicit Calabi-Yau metrics in six dimensions in terms of an initial hyperkahler structure is presented. The equations to solve are non linear in general, but become linear when the objects describing the metric depend on only one complex coordinate of the hyperkahler 4-dimensional space and its complex conjugated. This situation in

STAR Collaboration, B. I. Abelev

Parity-odd domains, corresponding to non-trivial topological solutions of the QCD vacuum, might be created during relativistic heavy-ion collisions. These domains are predicted to lead to charge separation of quarks along the orbital momentum of the system created in non-central collisions. To study this effect, we investigate a three particle mixed harmonic

P. Grange, J. -F. Mathiot, B. Mutet, E. Werner

The recently proposed renormalization scheme based on the definition of field operators as operator valued distributions acting on specific test functions is shown to be very convenient in explicit calculations of physical observables within the framework of light-front dynamics. We first recall the main properties of this procedure based on identities relat

Marco Larcher, Franco Dalfovo, Michele Modugno

We study the behaviour of an ultracold atomic gas of bosons in a bichromatic lattice, where the weaker lattice is used as a source of disorder. We numerically solve a discretized mean-field equation, which generalizes the one-dimensional Aubry-Andrè model for particles in a quasi-periodic potential by including the interaction between atoms. We compare the r

Ching-an Hsiao

Any problem is concerned with the mind, but what do minds make a decision on? Here we show that there are three conditions for the mind to make a certain answer. We found that some difficulties in physics and mathematics are in fact introduced by infinity, which can not be rightly expressed by minds. Based on this point, we suggest a general observation syst

P. Finelli, N. Kaiser, D. Vretenar, W. Weise

A previously derived relativistic energy density functional for nuclei, based on low-energy in-medium chiral dynamics, is generalized to implement constraints from chiral SU(3) effective field theory and applied to $\Lambda$ hypernuclei. Density-dependent central and spin-orbit mean fields are calculated for a $\Lambda$ hyperon using the SU(3) extension of i

Jürgen Röhler

We analyze the hole doping mechanism in Bi_2Sr_{2-x}La_xCuO_{6+δ} (BSLCO). The singular optimum around x=0.35 is found to be connected with a feedback between the doped CuO_2 layers and its dopant reactant [La^{3+}/Bi^{3+}-O_δ] locking the number of doped holes preferentially on to the universal optimum n_opt=0.16.

Peter Rakyta, Andor Kormanyos, Jozsef Cserti, Pekka Koskinen

We study theoretically the coherent electron focusing in graphene nanoribbons. Using semiclassical and numerical tight binding calculations we show that perfect armchair edges give rise to equidistant peaks in the focusing spectrum. In the case of zigzag edges at low magnetic fields one can also observe focusing peaks but with increasing magnetic field a mor

H. Bray, S. Brendle, M. Eichmair, A. Neves

Let (M,g) be a compact Riemannian manifold of dimension 3, and let \mathscr{F} denote the collection of all embedded surfaces homeomorphic to \mathbb{RP}^2. We study the infimum of the areas of all surfaces in \mathscr{F}. This quantity is related to the systole of (M,g). It makes sense whenever \mathscr{F} is non-empty. In this paper, we give an upper bound

L. D. Ferramacho, A. Blanchard, Y. Zolnierowski, A. Riazuelo

We investigate a class of dark energy models in which the equation of state undergoes a rapid transition and for which the Hubble SN Ia diagram is known to be poorly discriminant. Interestingly enough, we find that transitions at high redshift can lead to distortion in the correlation function of dark matter at lower redshift. We therefore use a combination

M. Garny, A. Hohenegger, A. Kartavtsev, M. Lindner

The generation of a baryon asymmetry via leptogenesis is usually studied by means of classical kinetic equations whose applicability to processes in the hot and expanding early universe is questionable. The approximations implied by the state-of-the-art description can be tested in a first-principle approach based on nonequilibrium field theory techniques. H

Karl-Hermann Neeb, Henrik Seppanen

Let $\cA$ be a commutative unital Banach algebra, $\g$ be a semisimple complex Lie algebra and $G(\cA)$ be the 1-connected Banach--Lie group with Lie algebra $\g \otimes \cA$. Then there is a natural concept of a parabolic subgroup $P(\cA)$ of $G(\cA)$ and we obtain generalizations $X(\cA) := G(\cA)/P(\cA)$ of the generalized flag manifolds. In this note we

Olivier Bernardi, Mireille Bousquet-Mélou

We address the enumeration of properly q-colored planar maps, or more precisely, the enumeration of rooted planar maps M weighted by their chromatic polynomial \chi_M(q) and counted by the number of vertices and faces. We prove that the associated generating function is algebraic when q\not=0,4 is of the form 2+2 cos (j\pi/m), for integers j and m. This incl

Nicole Mestrano, Carlos T. Simpson

In this note we consider the moduli space of stable bundles of rank two on a very general quintic surface. We study the potentially obstructed points of the moduli space via the spectral covering of a twisted endomorphism. This analysis leads to generically non-reduced components of the moduli space, and components which are generically smooth of more than t

Harvendra Singh

The Romans type IIA theory is the only known example of 10-dimensional maximal supergravity where (tensor) fields are explicitly massive. We provide an example of a non-relativistic anti-de Sitter $NRadS_4\times S^6$ background as a solution in massive type IIA. A compactification of which on $S^6$ gives immediately the prototype NRadS background in D=4 whic

Daniel Jezbera, David Kordek, Jan Kriz, Petr Seba

We experimentally demonstrate that the statistical properties of distances between pedestrians which are hindered from avoiding each other are described by the Gaussian Unitary Ensemble of random matrices. The same result has recently been obtained for an $n$-tuple of non-intersecting (one-dimensional, unidirectional) random walks. Thus, the observed behavio

Quan Zhou, Ke-Qing Xia

We report measurements of the instantaneous viscous boundary layer (BL) thickness $δ_v(t)$ in turbulent Rayleigh-Bénard convection. It is found that $δ_v(t)$ obtained from the measured instantaneous two-dimensional velocity field exhibits intermittent fluctuations. For small values, $δ_v(t)$ obeys a lognormal distribution, whereas for large values the distri

Marco Scutari

The structure of a Bayesian network encodes most of the information about the probability distribution of the data, which is uniquely identified given some general distributional assumptions. Therefore it's important to study the variability of its network structure, which can be used to compare the performance of different learning algorithms and to mea

T. M. Wright, A. S. Bradley, R. J. Ballagh

We perform finite-temperature dynamical simulations of the arrest of a rotating Bose-Einstein condensate by a fixed trap anisotropy, using a Hamiltonian classical-field method. We consider a quasi-two-dimensional condensate containing a single vortex in equilibrium with a rotating thermal cloud. Introducing an elliptical deformation of the trapping potential

Paolo E. Trevisanutto, Markus Holzmann, Michel Cote, Valerio Olevano

We present ab initio many-body calculations of the optical absorption in bulk graphite, graphene and bilayer of graphene. Electron-hole interaction is included solving the Bethe-Salpeter equation on top of a GW quasiparticle electronic structure. For all three systems, we observe strong excitonic effects at high energy, well beyond the continuum of π-> π* tr

K. Piasecki, T. Matulewicz, N. Yahlali, H. Delagrange

Differential cross sections of neutral pions emitted in 181Ta + 197Au collisions at a beam energy of 39.5A MeV have been measured with the photon spectrometer TAPS. The kinetic energy and transverse momentum spectra of neutral pions cannot be properly described in the framework of the thermal model, nor when the reabsorption of pions is accounted for in a ph

Sami Saxell

The three original publications in this thesis encompass various aspects in the still developing area of noncommutative quantum field theory, ranging from fundamental concepts to model building. One of the key features of noncommutative space-time is the apparent loss of Lorentz invariance that has been addressed in different ways in the literature. One rece

Sang Hoon Lee, Meesoon Ha, Hawoong Jeong, Jae Dong Noh

We study the critical behavior of the Ising model in annealed scale-free (SF) networks of finite system size with forced upper cutoff in degree. By mapping the model onto the weighted fully connected Ising model, we derive analytic results for the finite-size scaling (FSS) near the phase transition, characterized by the cutoff-dependent two-parameter scaling

Enrique González-Jiménez, Xavier Xarles

We give several criteria to show over which quadratic number fields Q(sqrt{D}) there should exists a non-constant arithmetic progressions of five squares. This is done by translating the problem to determining when some genus five curves C_D defined over Q have rational points, and then using a Mordell-Weil sieve argument among others. Using a elliptic Chaba

Luis Dieulefait, E. Gonzalez-Jimenez, J. Jimenez Urroz

For any elliptic curve E defined over the rationals with complex multiplication and for every prime p, we describe the image of the mod p Galois representation attached to E. We deduce information about the field of definition of torsion points of these curves, in particular we classify all cases where there are torsion points over Galois number fields not c

S. P. Cockburn, H. E. Nistazakis, T. P. Horikis, P. G. Kevrekidis

The dynamics of dark matter-wave solitons in elongated atomic condensates are discussed at finite temperatures. Simulations with the stochastic Gross-Pitaevskii equation reveal a noticeable, experimentally observable spread in individual soliton trajectories, attributed to inherent fluctuations in both phase and density of the underlying medium. Averaging ov

Marcello Ciafaloni, Paolo Ciafaloni, Denis Comelli

While radiative corrections of infrared origin normally depress high energy amplitudes (Sudakov form factors), we find that in some cases resummation of leading effects produces exponentials with positive exponents, giving rise to amplitudes that grow indefinitely with energy. The effect happens in broken gauge theories like the electroweak sector of the Sta

Dan Drake

We show combinatorially that the higher-order matching polynomials of several families of graphs are d-orthogonal polynomials. The matching polynomial of a graph is a generating function for coverings of a graph by disjoint edges; the higher-order matching polynomial corresponds to coverings by paths. Several families of classical orthogonal polynomials -- t

Zhi-Feng Sun, Xiang Liu

Inspired by the newly observed $D_{sJ}(3040)^+$ state, in this work we systemically study the two-body strong decays of P-wave charmed-strange mesons with the first radial excitation. Under the assignment of $1^{+}(j^P=1/2^+)$, i.e. the first radial excitation of $D_{s1}(2460)^+$, we find that the width of $D_{sJ}(3040)^+$ is close to the lower limit of the

C. Weber, A. Fuhrer, C. Fasth, G. Lindwall

Strong radial confinement in semiconductor nanowires leads to modified electronic and phononic energy spectra. We analyze the current response to the interplay between quantum confinement effects of the electron and phonon systems in a gate-defined double quantum dot in a semiconductor nanowire. We show that current spectroscopy of inelastic transitions betw

Krishnendu Chatterjee, Laurent Doyen, Thomas A. Henzinger

We study observation-based strategies for partially-observable Markov decision processes (POMDPs) with omega-regular objectives. An observation-based strategy relies on partial information about the history of a play, namely, on the past sequence of observations. We consider the qualitative analysis problem: given a POMDP with an omega-regular objective, whe

Pierre Thibault

We comment on the recent manuscript by Raines et al. [arXiv:0905.0269v2] (now published in Nature, vol. 463, p. 214-217, 2010), which suggests that in certain conditions a single diffraction measurement may be sufficient to reconstruct the full three-dimensional density of a scatterer. We show that past literature contains the tools to assess rigorously the

Amir Levinson

Global linear stability analysis of a self-similar solution describing the interaction of a relativistic shell with an ambient medium is performed. The solution is shown to be unstable to convective Rayleigh-Taylor modes having angular scales smaller than the causality scale. Longer wavelength modes are stable and decay with time. For modes of sufficiently l

Fu-Lin Zhang, Jing-Ling Chen, Chang-Liang Ren, Ming-Jun Shi

The quantum probability distribution arising from single-copy von Neumann measurements on an arbitrary two-qubit state is decomposed into the local and nonlocal parts, in the approach of Elitzur, Popescu and Rohrlich [A. Elitzur, S. Popescu, and D. Rohrlich, Phys. Lett. A 162, 25 (1992)]. A lower bound of the local weight is proved being connected with the c

Yu. Eltsev, S. Lee, K. Nakao, S. Tajima

We have studied electrical transport properties of a high quality Bi2Sr2Ca2Cu3O10+x crystal below a superconducting critical temperature, Tc. In magnetic fields B parallel to the c-axis just above a voltage response onset resistance vs temperature data are well fitted to the vortex-glass model. Obtained from the vortex-glass analysis a melting transition bou

Hiroki Matui

For almost finite groupoids, we study how their homology groups reflect dynamical properties of their topological full groups. It is shown that two clopen subsets of the unit space has the same class in H_0 if and only if there exists an element in the topological full group which maps one to the other. It is also shown that a natural homomorphism, called th

Toshihiro Matsuo

We calculate emission rates of a massless state from a highly excited rotating string in perturbative bosonic open string theory. By averaging huge degeneracies of initial string states with specifying the mass and a single component of the angular momentum, we find thermal spectrum in a wide range of the angular momentum. We derive the temperature that char

Yuli B. Rudyak

Farber introduced a notion of topological complexity $\TC(X)$ that is related to robotics. Here we introduce a series of numerical invariants $\TC_n(X), n=1,2, ...$ such that $\TC_2(X)=\TC(X)$ and $\TC_n(X)\le \TC_{n+1}(X)$. For these higher complexities, we define their symmetric versions that can also be regarded as higher analogs of the symmetric topologi

Michael Dine, John Kehayias

If nature exhibits low energy supersymmetry, discrete (non-$Z_2$) R symmetries may well play an important role. In this paper, we explore such symmetries. We generalize gaugino condensation, constructing large classes of models which are classically scale invariant, and which spontaneously break discrete R symmetries (but not supersymmetry). The order parame

Kyungyong Lee, Li Li

Let $I$ be the ideal generated by alternating polynomials in two sets of $n$ variables. Haiman proved that the $q,t$-Catalan number is the Hilbert series of the graded vector space $M(=\bigoplus_{d_1,d_2}M_{d_1,d_2})$ spanned by a minimal set of generators for $I$. In this paper we give simple upper bounds on $\text{dim}M_{d_1, d_2}$ in terms of partition nu

Hiroyuki Kamano

The master formula approach to chiral symmetry breaking proposed by Yamagishi and Zahed is extended to the U_R(3)xU_L(3) group, in which effects of the U_A(1) anomaly and the flavor symmetry breaking m_u \not= m_d \not= m_s are properly contained. New identities for the gluon topological susceptibility and pi^0, eta, eta' -> gamma^(*) gamma^(*) decays ar

Atsushi Nakamula, Jun Sakaguchi

Analytic Nahm data is re-examined for SU(2) calorons, or periodic instantons, of instanton charge 2. The Nahm equations are solved analytically in terms of Jacobi elliptic functions and the possible matching conditions are classified. The dimensions of framed moduli space for charge 2 caloron is enumerated and the maximal parameter, which is 16 for charge 2,

Xiao-yu Chen

The entanglement of graph states up to eight qubits is calculated in the regime of iteration calculation. The entanglement measures could be the relative entropy of entanglement, the logarithmic robustness or the geometric measure. All 146 local inequivalent graphs are classified as two categories: graphs with identical upper LOCC entanglement bound and lowe

Ha Q. Nguyen, Vivek K Goyal, Lav R. Varshney

Frame permutation quantization (FPQ) is a new vector quantization technique using finite frames. In FPQ, a vector is encoded using a permutation source code to quantize its frame expansion. This means that the encoding is a partial ordering of the frame expansion coefficients. Compared to ordinary permutation source coding, FPQ produces a greater number of p

Shan-Gui Zhou, Jie Meng, P. Ring, En-Guang Zhao

Halo phenomena in deformed nuclei are investigated within a deformed relativistic Hartree Bogoliubov (DRHB) theory. These weakly bound quantum systems present interesting examples for the study of the interdependence between the deformation of the core and the particles in the halo. Contributions of the halo, deformation effects, and large spatial extensions

S. G. Schirmer, Xiaoting Wang

We study open quantum systems whose evolution is governed by a master equation of Kossakowski-Gorini-Sudarshan-Lindblad type and give a characterization of the convex set of steady states of such systems based on the generalized Bloch representation. It is shown that an isolated steady state of the Bloch equation cannot be a center, i.e., that the existence

Bryden Cais

Let A be the Néron model of an abelian variety A_K over the fraction field K of a discrete valuation ring R. Due to work of Mazur-Messing, there is a functorial way to prolong the universal extension of A_K by a vector group to a smooth and separated group scheme over R, called the canonical extension of A. In this paper, we study the canonical extension whe

Tarun Biswas

The Higgs mechanism is designed to generate mass for massless particles. The mass comes from the interaction of observed particles with an external field -- the Higgs field. In the past, several alternatives to the Higgs mechanism for mass generation have been proposed to avoid the postulation of the Higgs field. This article proposes yet another one. This a

A. D. Polyanin, S. N. Aristov

Systems of hydrodynamic type equations derived from the Navier-Stokes equations and the boundary layer equations are considered. A transformation of the Crocco type reducing the equation order for the longitudinal velocity component is described. The issues of nonlinear stability of the obtained solutions are studied. It is found that a specific feature of m

Barak Bringoltz, Stephen R. Sharpe

It has been proposed that four-dimensional QCD with fermions in the adjoint representation exhibits volume-independence in the large-N limit. If correct, this would mean that results for physical quantities could be obtained from the single-site version of the model. A necessary condition for volume-independence is that the (Z_N)^4 center-symmetry of the sin

Pavel Fileviez Perez, Sogee Spinner

Understanding the origin or absence of the R-parity violating interactions in the minimal supersymmetric Standard Model is a vital and open issue. Here we show that in the minimal B-L models, R-parity and B-L are spontaneously broken at the TeV scale. We also briefly discuss the phenomenological and cosmological aspects of these scenarios.

G. Ramos-Larios, J. P. Phillips

The motion of planetary nebulae (PNe) through the interstellar medium (ISM) is thought to lead to a variety of observational consequences, including the formation of bright rims; deformation and fragmentation of the shells; and a shift of the central stars away from the geometric centres of the envelopes. These and other characteristics have been noted throu

Erminia Calabrese, Joseph Smidt, Alexandre Amblard, Asantha Cooray

We measure the skewness power spectrum of the Cosmic Microwave Background (CMB) anisotropies optimized for a detection of the secondary bispectrum generated by the correlation of the CMB lensing potential with integrated Sachs-Wolfe effect and the Sunyaev-Zel'dovich effect. The covariance of our measurements is generated by Monte-Carlo simulations of Gau

Uma Gorti, Kees Dullemond, David Hollenbach

We present the time evolution of viscously accreting circumstellar disks as they are irradiated by ultraviolet and X-ray photons from a low-mass central star. Our model is a hybrid of a 1D time-dependent viscous disk model coupled to a 1+1D disk vertical structure model used for calculating the disk structure and photoevaporation rates. We find that disks of

D. M. S. Johnson, J. M. Hogan, S. -w. Chiow, M. A. Kasevich

We demonstrate serrodyne frequency shifting of light from 200 MHz to 1.2 GHz with an efficiency of better than 60 percent. The frequency shift is imparted by an electro-optic phase modulator driven by a high-frequency, high-fidelity sawtooth waveform that is passively generated by a commercially available Non-Linear Transmission Line (NLTL). We also implemen

Michal Feckan, Vassilis Rothos

Existence and bifurcation results are derived for quasi periodic traveling waves of discrete nonlinear Schrodinger equations with nonlocal interactions and with polynomial type potentials. Variational tools are used. Several concrete nonlocal interactions are studied as well.

Yacov Kantor, Mehran Kardar

We study thermodynamics properties of a one dimensional gas of hard elongated particles. The particle centers are restricted to a line, while they can rotate in two-dimensional space. Correlations between orientations of the objects are studied (by transfer matrix method) as a function of density and aspect ratio. The behavior in the extreme high-density (ja

Ngo Minh Toan, D. Thirumalai

We provide a unified theory for the high force elasticity of biopolymers solely in terms of the persistence length, $ξ_p$, and the monomer spacing, $a$. When the force $f>\fh \sim k_BTξ_p/a^2$ the biopolymers behave as Freely Jointed Chains (FJCs) while in the range $\fl \sim k_BT/ξ_p < f < \fh$ the Worm-like Chain (WLC) is a better model. We show that $ξ_p$

Deniz Ustebay, Boris Oreshkin, Mark Coates, Michael Rabbat

This paper presents greedy gossip with eavesdropping (GGE), a novel randomized gossip algorithm for distributed computation of the average consensus problem. In gossip algorithms, nodes in the network randomly communicate with their neighbors and exchange information iteratively. The algorithms are simple and decentralized, making them attractive for wireles

J. P. Phillips, G. Ramos-Larios, K. -P. Schroeder, J. L. Verbena Contreras

We present images of the planetary nebulae (PNe) NGC 7354 and NGC 3242 in four mid-infrared (MIR) photometric bands centred at 3.6, 4.5, 5.8 and 8.0 microns; the results of observations undertaken using the Spitzer Space Telescope (SST). The resulting images show the presence of a halo and rings in NGC 3242, as previously observed through narrow band imaging

Greg Knese

A certain kernel (sometimes called the Pick kernel) associated to Schur functions on the disk is always positive semi-definite. A generalization of this fact is well-known for Schur functions on the polydisk. In this article, we show that the Pick kernel on the polydisk has a great deal of structure beyond being positive semi-definite. It can always be split

Nicole Ackerman

EXO-200 is the first phase of the Enriched Xenon Observatory (EXO) experiment, which searches for neutrinoless double beta decay in 136Xe to measure the mass and probe the Majorana nature of the neutrino. EXO-200 consists of 200 kg of liquid Xe enriched to 80% in 136Xe in an ultra-low background TPC. Energy resolution is enhanced through the simultaneous col

Pavel Lukashev, Renat F. Sabirianov, Kirill Belashchenko

In this paper we present results of our calculations of the non-collinear spin density distribution in the systems with frustrated triangular magnetic structure (Mn-based antiperovskite compounds, Mn_{3}AN (A=Ga, Zn)) in the ground state and under external mechanical strain. We show that the spin density in the (111)-plane of the unit cell forms a &#34;domai

Greg Knese

We prove a detailed sums of squares formula for two variable polynomials with no zeros on the bidisk $\mathbb{D}^2$ extending previous versions of such a formula due to Cole-Wermer and Geronimo-Woerdeman. The formula is related to the Christoffel-Darboux formula for orthogonal polynomials on the unit circle, but the extension to two variables involves issues

Christopher C. Stark, Marc J. Kuchner, Wesley A. Traub, John D. Monnier

We present observations of the 51 Ophiuchi circumstellar disk made with the Keck interferometer operating in nulling mode at N-band. We model these data simultaneously with VLTI-MIDI visibility data and a Spitzer IRS spectrum using a variety of optically-thin dust cloud models and an edge-on optically-thick disk model. We find that single-component optically