May 2008 arXiv papers — page 15

Florent Krzakala, Marco Tarzia, Lenka Zdeborová

We study a lattice model of attractive colloids. It is exactly solvable on sparse random graphs. As the pressure and temperature are varied it reproduces many characteristic phenomena of liquids, glasses and colloidal systems such as ideal gel formation, liquid-glass phase coexistence, jamming, or the reentrance of the glass transition.

M. A. Anacleto, C. Furtado, J. R. Nascimento, A. Yu. Petrov

In this paper, we use gauge embedding procedure and master action approach to establish the equivalence between the self-dual and Maxwell-Chern-Simons models with Lorentz symmetry breaking. As a result, new kinds of Lorentz-breaking terms arise.

E. Ryckman

For arbitrary $β> 0$, we use the orthogonal polynomials techniques developed by R. Killip and I. Nenciu to study certain linear statistics associated with the circular and Jacobi $β$ ensembles. We identify the distribution of these statistics then prove a joint central limit theorem. In the circular case, similar statements have been proved using different m

Lance J. Dixon, Lorenzo Magnea, George Sterman

We study the origin of subleading soft and collinear poles of form factors and amplitudes in dimensionally-regulated massless gauge theories. In the case of form factors of fundamental fields, these poles originate from a single function of the coupling, denoted G(alpha_s), depending on both the spin and gauge quantum numbers of the field. We relate G(alpha_

Abhay Ashtekar, Edward Wilson-Ewing

We examine Bousso's covariant entropy bound conjecture in the context of radiation filled, spatially flat, Friedmann-Robertson-Walker models. The bound is violated near the big bang. However, the hope has been that quantum gravity effects would intervene and protect it. Loop quantum cosmology provides a near ideal setting for investigating this issue. Fo

C. Tuchendler, A. M. Lance, A. Browaeys, Y. R. P. Sortais

We investigate experimentally the energy distribution of a single rubidium atom trapped in a strongly focused dipole trap under various cooling regimes. Using two different methods to measure the mean energy of the atom, we show that the energy distribution of the radiatively cooled atom is close to thermal. We then demonstrate how to reduce the energy of th

Joris Raeymaekers, Walter Van Herck, Bert Vercnocke, Thomas Wyder

We analyze the map between a class of `fuzzball' solutions in five dimensions and four-dimensional multicentered solutions under the 4D-5D connection, and interpret the resulting configurations in the framework of Denef and Moore. In five dimensions, we consider Kaluza-Klein monopole supertubes with circular profile which represent microstates of a small

Wei-Hao Wang, Amy J. Barger, Lennox L. Cowie

GOODS 850-5 is a hyperluminous radio-faint submillimeter source in the GOODS-N. Although it is generally agreed that GOODS 850-5 is at a high redshift z>~4, its exact redshift is unknown. While its stellar SED suggests z~6, its radio/FIR SED suggests a lower redshift of z~4. To better constrain its stellar SED and redshift, we carried out nano-Jansky sensiti

M. S. Baptista, F. Moukam Kakmeni, Gianluigi Del Magno, M. S. Hussein

Positive Lyapunov exponents measure the asymptotic exponential divergence of nearby trajectories of a dynamical system. Not only they quantify how chaotic a dynamical system is, but since their sum is an upper bound for the entropy by the Ruelle inequality, they also provide a convenient way to quantify the complexity of an active network. We present numeric

Damien Calaque, Carlo A. Rossi

In this paper we prove, with details and in full generality, that the isomorphism induced on tangent homology by the Shoikhet-Tsygan formality $L_\infty$-quasi-isomorphism for Hochschild chains is compatible with cap-products. This is a homological analog of the compatibility with cup-products of the isomorphism induced on tangent cohomology by Kontsevich fo

Ajay Majethiya, Bhavin Patel, P. C. Vinodkumar

Properties of single heavy flavor baryons in a non relativistic potential model with colour coulomb plus power law confinement potential have been studied. The ground state masses of single heavy baryons and the mass difference between the ($J^{P}={3/2}^{+}$ and $J^{P}={1/2}^{+}$) states are computed using a spin dependent two body potential. Using the spin-

A. S. Richardson, E. R. Tracy

The effects of quadratic order terms in the dispersion matrix near a mode conversion are considered. It is shown that including the corrections due to these quadratic terms gives a better matching between the local solution in the mode conversion region, and the far-field WKB solutions for the incoming and outgoing waves. This matching is demonstrated by com

Miao Li, Tower Wang

By turning on antisymmetric background fluxes, we study how multiple M2-branes are coupled to them. Our investigation concentrates on the gauge invariance conditions for the Myers-Chern-Simons action. Furthermore, the dimensional reduction of M2-branes to D2-branes introduces more constraints on the newly introduced tensors. Particularly, for the theory base

M. Ossadnik, C. Honerkamp, T. M. Rice, M. Sigrist

We use the functional renormalization group to analyze the temperature dependence of the quasi-particle scattering rates in the two-dimensional Hubbard model below half-filling. Using a band structure appropriate to overdoped Tl2Ba2CuO(6+x) we find a strongly angle dependent term linearly dependent on temperature which derives from an increasing scattering v

J. G. Russo, P. K. Townsend

We define the local acceleration and jerk of a relativistic brane in an ambient spacetime, and construct from them a dimensionless parameter lambda that must be small for an interpretation of brane acceleration as local Unruh temperature. As examples, we discuss (i) open rotating branes, for which lambda>1 (ii) closed spherical branes expanding in Minkowski

Yoshihiro Nambu

We present a new and feasible test proving quantum contextuality in four-dimensional Hiltbert space. In our scheme, a contradiction between quantum mechanics and noncontextual hidden variables is revealed through the measurement statistics of two joint measurements of an ensemble of non-entangled qubits. The origin of nonclassicality is fully attributed to t

P. Q. Hung

If right-handed neutrinos are {\em not} singlets under the electroweak gauge group as it was proposed in a recent model, they can acquire electroweak scale masses and are thus accessible experimentally in the near future. When this idea is combined with quark-lepton unification à la Pati-Salam, one is forced to introduce new neutral particles which are singl

T. Lund-Hansen, S. Stobbe, B. Julsgaard, H. Thyrrestrup

We present time-resolved spontaneous emission measurements of single quantum dots embedded in photonic crystal waveguides. Quantum dots that couple to the photonic crystal waveguide are found to decay up to 27 times faster than uncoupled quantum dots. From these measurements $β$-factors of up to 0.89 are derived, and an unprecedented large bandwidth of 20 nm

J. L. Cortes, J. Indurain

The possibility of having an extension of the cosmological standard model with a Hubble expansion rate $H$ constrained to a finite interval is considered. Two periods of accelerated expansion arise naturally when the Hubble expansion rate approaches to the two limiting values. The new description of the history of the universe is confronted with cosmological

R. R. Metsaev

Conformal totally symmetric arbitrary spin currents and shadow fields in flat space-time of dimension greater than or equal to four are studied. Gauge invariant formulation for such currents and shadow fields is developed. Gauge symmetries are realized by involving the Stueckelberg fields. Realization of global conformal boost symmetries is obtained. Gauge i

K. Atazadeh, F. Darabi, H. R. Sepangi

We study the correspondence between two theoretical frameworks for describing dark energy, $f(R)$ gravity and higher-dimensional Space-Time-Matter (STM) or induced-matter theory. We show that the Hubble expansion parameter in $f(R)$ gravity can be associated with a combination of metric functions in STM theory, and consider a specific example whose propertie

Charlie Conroy, Risa H. Wechsler

A simple, observationally-motivated model is presented for understanding how halo masses, galaxy stellar masses, and star formation rates are related, and how these relations evolve with time. The relation between halo mass and galaxy stellar mass is determined by matching the observed spatial abundance of galaxies to the expected spatial abundance of halos

Kevin Stokely, Marco G. Mazza, H. Eugene Stanley, Giancarlo Franzese

Four scenarios have been proposed for the low--temperature phase behavior of liquid water, each predicting different thermodynamics. The physical mechanism which leads to each is debated. Moreover, it is still unclear which of the scenarios best describes water, as there is no definitive experimental test. Here we address both open issues within the framewor

Federico A. Ceccopieri, Luca Trentadue

We evaluate in perturbative QCD the semi-inclusive Drell-Yan cross-section for the production of a single hadron accompaining the lepton pair. We demonstrate to one loop level a collinear factorization formula within the fracture functions approach. We propose such a process as a factorization analyzer in hadronic collisions. Phenomenological implications at

Andrea Casaccino, Ernesto F. Galvao, Simone Severini

We study the class of discrete Wigner functions proposed by Gibbons et al. [Phys. Rev. A 70, 062101 (2004)] to describe quantum states using a discrete phase-space based on finite fields. We find the extrema of such functions for small Hilbert space dimensions, and present a quantum information application: a construction of quantum random access codes. Thes

Changxing Miao, Gang Wu

We make use of the method of modulus of continuity \cite{K-N-S} and Fourier localization technique \cite{A-H} to prove the global well-posedness of the critical Burgers equation $\partial_{t}u+u\partial_{x}u+Λu=0$ in critical Besov spaces $\dot{B}^{\frac{1}{p}}_{p,1}(\mathbb{R})$ with $p\in[1,\infty)$, where $Λ=\sqrt{-\triangle}$.

Liping Wang

In this paper we compute the leading coefficients $μ(u,w)$ of the Kazhdan--Lusztig polynomials $P_{u,w}$ for an affine Weyl group of type $\tilde{B}_2$. By using the \textbf{a}-function of a Coxeter group defined by Lusztig (see [L1, \S2]), we compute most $μ(u,w)$ explicitly. With part of these values $μ(u,w)$, we show that a conjecture of Lusztig on distin

Alessandro Ferrante, Aniello Murano, Mimmo Parente

The model checking problem for open systems has been intensively studied in the literature, for both finite-state (module checking) and infinite-state (pushdown module checking) systems, with respect to Ctl and Ctl*. In this paper, we further investigate this problem with respect to the μ-calculus enriched with nominals and graded modalities (hybrid graded M

P. Simon, M. Hetterscheidt, C. Wolf, K. Meisenheimer

This paper studies the relative spatial distribution of red-sequence and blue-cloud galaxies, and their relation to the dark matter distribution in the COMBO-17 survey as function of scale down to z~1. We measure the 2nd-order auto- and cross-correlation functions of galaxy clustering and express the relative biasing by using aperture statistics. Also estima

Laurent Moret-Bailly, Alexandra Shlapentokh

Let $K$ be a one-variable function field over a field of constants of characteristic 0. Let $R$ be a holomorphy subring of $K$, not equal to $K$. We prove the following undecidability results for $R$: If $K$ is recursive, then Hilbert's Tenth Problem is undecidable in $R$. In general, there exist $x_1,...,x_n \in R$ such that there is no algorithm to tel

N. Bergeal, R. Vijay, V. E. Manucharyan, I. Siddiqi

Amplifiers are crucial in every experiment carrying out a very sensitive measurement. However, they always degrade the information by adding noise. Quantum mechanics puts a limit on how small this degradation can be. Theoretically, the minimum noise energy added by a phase preserving amplifier to the signal it processes amounts at least to half a photon at t

Andras Nemethi, Patrick Popescu-Pampu

The oriented link of the cyclic quotient singularity $\mathcal{X}_{p,q}$ is orientation-preserving diffeomorphic to the lens space $L(p,q)$ and carries the standard contact structure $ξ_{st}$. Lisca classified the Stein fillings of $(L(p,q), ξ_{st})$ up to diffeomorphisms and conjectured that they correspond bijectively through an {\it explicit} map to the M

David Gomez-Ullate, Niky Kamran, Robert Milson

A classical result due to Bochner characterizes the classical orthogonal polynomial systems as solutions of a second-order eigenvalue equation. We extend Bochner's result by dropping the assumption that the first element of the orthogonal polynomial sequence be a constant. This approach gives rise to new families of complete orthogonal polynomial systems

A. J. Ferguson

A superconducting tunnel junction is used to directly extract quasiparticles from one of the leads of a single-Cooper-pair-transistor. The consequent reduction in quasiparticle density causes a lower rate of quasiparticle tunneling onto the device. This rate is directly measured by radio-frequency reflectometry. Local cooling may be of direct benefit in redu

Nobuyuki Sakai, Kaiki Taro Inoue

We study the cosmic microwave background (CMB) anisotropy due to spherically symmetric nonlinear structures in flat universes with dust and a cosmological constant. By modeling a time-evolving spherical compensated void/lump by Lemaitre-Tolman-Bondi spacetimes, we numerically solve the null geodesic equations with the Einstein equations. We find that a nonli

A. V. Tsiganov

We propose new construction of the polynomial integrals of motion related to the addition theorems. As an example we reconstruct Drach systems and get some new two-dimensional superintegrable Stackel systems with third, fifth and seventh order integrals of motion.

Dan Radu Grigore

Quantum theory of the gravitation in the causal approach is studied up to the second order of perturbation theory. We prove gauge invariance and renormalizability in the second order of perturbation theory for the pure gravity system (massless and massive). Then we investigate the interaction of massless gravity with matter (described by scalars and spinors)

Kumar S. Gupta, Siddhartha Sen

We present a quantum analysis of the massless excitations in graphene with a charge impurity. When the effective charge exceeds a certain critical value, the spectrum is quantized and is unbounded from below. The corresponding eigenstates are square-integrable at infinity and have a rapidly oscillatory behaviour in the short distance, which can be interprete

Baojiu Li, David F. Mota, Douglas J. Shaw

We show that, within modified gravity, the non-linear nature of the field equations implies that the usual naive averaging procedure (replacing the microscopic energy-momentum by its cosmological average) is invalid. We discuss then how the averaging should be performed correctly and show that, as a consequence, at classical level the physical masses and geo

Nicole F. Bell, James B. Dent, Thomas D. Jacques, Thomas J. Weiler

A conservative upper bound on the total dark matter (DM) annihilation rate can be obtained by constraining the appearance rate of the annihilation products which are hardest to detect. The production of neutrinos, via the process $χχ\to \barνν$, has thus been used to set a strong general bound on the dark matter annihilation rate. However, Standard Model rad

Gregory Ginot, Melchior Grutzmann

We study the (standard) cohomology $H^\bullet_{st}(E)$ of a Courant algebroid $E$. We prove that if $E$ is transitive, the standard cohomology coincides with the naive cohomology $H_{naive}^\bullet(E)$ as conjectured by Stienon and Xu. For a general Courant algebroid we define a spectral sequence converging to its standard cohomology. If $E$ is with split ba

A. Fourrière, P. Claudin, B. Andreotti

It is widely accepted that both ripples and dunes form in rivers by primary linear instability, the wavelength of the former scaling on the grain size, that of the latter being controled by the water depth. We revisit here this problem, using the computation of the turbulent flow over a wavy bottom performed in Part 1. The details of the different mechanisms

Prasanna D. Kulkarni, U. V. Vaidya, V. C. Rakhecha, A. Thamizhavel

The results of dc and ac magnetization, electrical resistance and heat capacity studies in an admixed rare earth alloy Nd0.75Gd0.25Rh3B2, which is close to the zero magnetization limit, are reported. Novel observations include the two antiferromagnetic like transitions, concomitant repeated/multiple magnetic compensation behaviour and a characteristic oscill

De-Min Li, Shan Zhou

The strong decays of the $π(2070)$, $η(2010)$, $η(2100)$, $η(2190)$, and $η(2225)$ as the $4 ^1S_0$ quark-antiquark states are investigated in the framework of the $^3P_0$ meson decay model. It is found that the $π(2070)$, $η(2100)$, and $η(2225)$ appear to be the convincing $4 ^1S_0$ $q\bar{q}$ states while the assignment of the $η(2010)$ and $η(2190)$ as t

Dirk Helbing, Anders Johansson

Daganzo's criticisms of second-order fluid approximations of traffic flow [C. Daganzo, Transpn. Res. B. 29, 277-286 (1995)] and Aw and Rascle's proposal how to overcome them [A. Aw and M. Rascle, SIAM J. Appl. Math. 60, 916-938 (2000)] have stimulated an intensive scientific activity in the field of traffic modeling. Here, we will revisit their argum

Dinesh K. Srivastava

We recall the seminal developments in the study of radiation of direct photons from relativistic heavy ion collisions, which have helped to enhance the scope of single photons as a probe of the quark gluon plasma considerably. There is a mounting evidence that in addition to providing information about the initial temperature of the plasma as envisaged origi

Matus Medo, Chi Ho Yeung, Yi-Cheng Zhang

When assets are correlated, benefits of investment diversification are reduced. To measure the influence of correlations on investment performance, a new quantity - the effective portfolio size - is proposed and investigated in both artificial and real situations. We show that in most cases, the effective portfolio size is much smaller than the actual number

S. Gustavsson, M. Studer, R. Leturcq, T. Ihn

We use time-resolved charge detection techniques to probe virtual tunneling processes in a double quantum dot. The process involves an energetically forbidden state separated by an energy $δ$ from the Fermi energy in the leads. The non-zero tunneling probability can be interpreted as cotunneling, which occurs as a direct consequence of time-energy uncertaint

A. Ardizzoni

The main aim of this paper is to investigate the structure of primitively generated connected braided bialgebras $A$ with respect to the braided vector space $P$ consisting of their primitive elements. When the Nichols algebra of $P$ is obtained dividing out the tensor algebra $T(P) $ by the two-sided ideal generated by its primitive elements of degree at le

Majid Ghojavand

For technological purposes and theoretical curiosity, it is very interesting to have a building block that produces a considerable amount of entanglement between on-demand sites through a simple control of a few sites. Here, we consider permanently-coupled spin networks and study entanglement generation between qubit pairs to find low-complexity structures c

Toshifumi Jittoh, Kazunori Kohri, Masafumi Koike, Joe Sato

A scenario of the Big-Bang Nucleosynthesis is analyzed within the Minimal Supersymmetric Standard Model which is consistent with a stau-neutralino coannihilation scenario to explain the relic abundance of dark matter. We find that we can account for the possible descrepancy of the abundance of $\mathrm{^{7}Li}$ between the observation and the prediction of t

Belle Collaboration, S. Uehara, Y. Watanabe

We present a high-statistics measurement of differential cross sections and the total cross section for the process gamma gamma -> pi^0 pi^0 in the kinematic range 0.6 GeV <= W <= 4.0 GeV and |cos theta*| <= 0.8, where W and theta* are the energy and pion scattering angle, respectively, in the gamma gamma center-of-mass system. Differential cross sections ar

Fu-Gao Song

At present, it is widely believed that the phenomenon of the gamma-ray burst redshift is cosmological origin. From a theoretical point of view, this redshift has either a cosmological or a cause that is related to gravity. However, the question of whether the gamma-ray burst redshift has a cosmological origin or not should be answerable in no uncertain terms

Tatsuya Tate

We define the notion of Bernstein measures and Bernstein approximations over general convex polytopes. This generalizes well-known Bernstein polynomials which are used to prove the Weierstrass approximation theorem on one dimensional intervals. We discuss some properties of Bernstein measures and approximations, and prove an asymptotic expansion of the Berns

Yoshiaki Maeda, Akifumi Sako

We construct instanton solutions on noncommutative Euclidean 4-space which are deformations of instanton solutions on commutative Euclidean 4-space. We show that the instanton numbers of these noncommutative instanton solutions coincide with the commutative solutions and conjecture that the instanton number in R^4 is preserved for general noncommutative defo

I. Casinos

The nuclear interaction is responsible for keeping neutrons and protons joined in an atomic nucleus. Phenomenological nuclear potentials, fitted to experimental data, allow one to know about the nuclear behaviour with more or less success where quantum mechanics is hard to be used. A nuclear potential is suggested and an expression for the potential energy o

D0 Collaboration, V. Abazov

Data recorded by the D0 experiment at the Fermilab Tevatron Collider are analyzed to search for neutral Higgs bosons produced in association with $b$ quarks. This production mode can be enhanced in the minimal supersymmetric standard model (MSSM). The search is performed in the three $b$ quark channel using multijet triggered events corresponding to an integ

M. A. Urbaneja, R. -P. Kudritzki, F. Bresolin, N. Przybilla

The quantitative analysis of low resolution spectra of A and B supergiants is used to determine a distance modulus of 24.99 +/- 0.10 mag (995 +/- 46 Kpc) to the Local Group galaxy WLM. The analysis yields stellar effective temperatures and gravities, which provide a distance through the Flux weighted Gravity--Luminosity Relationship (FGLR). Our distance is 0

Tuncay Aktosun, Vassilis G. Papanicolaou

The time evolution of the scattering and spectral data is obtained for the differential operator $\displaystyle\frac{d^4}{dx^4} +\displaystyle\frac{d}{dx} u(x,t)\displaystyle\frac{d}{dx}+v(x,t),$ where $u(x,t)$ and $v(x,t)$ are real-valued potentials decaying exponentially as $x\to\pm\infty$ at each fixed $t.$ The result is relevant in a crucial step of the

S. A. Pustilnik, A. L. Tepliakova, A. Y. Kniazev, A. N. Burenkov

The Local Volume dwarf galaxy DDO 68, from the spectroscopy of its two brightest HII regions (Knots 1 and 2) was designated as the second most metal-poor star-forming galaxy [12+log(O/H)=7.14]. In the repeated spectral observations in 2008 January with the 6-m telescope (BTA) of the HII region Knot 3 [having 12+log(O/H)=7.10+-0.06], we find a strong evidence

S. R. Hassan, L. de&#39; Medici

A new slave-spin representation of fermion operators has recently been proposed for the half-filled Hubbard model. We show that with the addition of a gauge variable, the formalism can be extended to finite doping. The resulting spin problem can be solved using the cluster mean-field approximation. This approximation takes short-range correlations into accou

Katherine Freese, Paolo Gondolo, J. A. Sellwood, Douglas Spolyar

The first stars in the universe form inside $\sim 10^6 M_\odot$ dark matter (DM) haloes whose initial density profiles are laid down by gravitational collapse in hierarchical structure formation scenarios. During the formation of the first stars in the universe, the baryonic infall compresses the dark matter further. The resultant dark matter density is pres

Wojciech Mazurczyk, Krzysztof Szczypiorski

In this paper, we evaluate available steganographic techniques for SIP (Session Initiation Protocol) that can be used for creating covert channels during signaling phase of VoIP (Voice over IP) call. Apart from characterizing existing steganographic methods we provide new insights by introducing new techniques. We also estimate amount of data that can be tra

Fang Wu, Bernardo A. Huberman

We performed a massive study of the dynamics of group deliberation among several websites containing millions of opinions on topics ranging from books to media. Contrary to the common phenomenon of group polarization observed offline, we measured a strong tendency towards moderate views in the course of time. This phenomenon possibly operates through a self-

Z. Han, Ph. Podsiadlowski

In this talk, we present the general principles of binary evolution and give two examples. The first example is the formation of subdwarf B stars (sdBs) and their application to the long-standing problem of ultraviolet excess (also known as UV-upturn) in elliptical galaxies. The second is for the progenitors of type Ia supernovae (SNe Ia). We discuss the mai

Stefano De Marchi, Marco Vianello, Yuan Xu

A new algebraic cubature formula of degree $2n+1$ for the product Chebyshev measure in the $d$-cube with $\approx n^d/2^{d-1}$ nodes is established. The new formula is then applied to polynomial hyperinterpolation of degree $n$ in three variables, in which coefficients of the product Chebyshev orthonormal basis are computed by a fast algorithm based on the 3

Congjun Wu

We investigate the topological insulating states of the $p$-band systems in optical lattices induced by the onsite orbital angular momentum polarization, which exhibit gapless edge modes in the absence of Landau levels. This effect arises from the energy level splitting between the onsite $p_x+ip_y$ and $p_x-ip_y$ orbitals by rotating each optical lattice si

Kevin K. Lin, Eric Shea-Brown, Lai-Sang Young

We study the reliability of large networks of coupled neural oscillators in response to fluctuating stimuli. Reliability means that a stimulus elicits essentially identical responses upon repeated presentations. We view the problem on two scales: neuronal reliability, which concerns the repeatability of spike times of individual neurons embedded within a net

Yahya Ould Hamidoune

We introduce the notion of a hyper-atom. One of the main results of this paper is the $\frac{2|G|}3$--Theorem: Let $S$ be a finite generating subset of an abelian group $G$ of order $\ge 2$. Let $T$ be a finite subset of $G$ such that $2\le |S|\le |T|$, $S+T$ is aperiodic, $0\in S\cap T$ and $$ \frac{2|G|+2}3\ge |S+T|= |S|+|T|-1.$$ Let $H$ be a hyper-atom of

W. -M. Wang, Zhifei Zhang

We prove long time Anderson localization for nonlinear random Schroedinger equation in $\ell^2$ by making a Birkoff normal form type transform to creat an energy barrier where there is essentially no mode propagation. One of the new features is that this transform is in a small neighborhood enabling us to treat &#34;rough&#34; data, where there are no moment

P. Cladé, C. Ryu, A. Ramanathan, K. Helmerson

We present experimental results on a Bose gas in a quasi-2D geometry near the Berezinskii, Kosterlitz and Thouless (BKT) transition temperature. By measuring the density profile, \textit{in situ} and after time of flight, and the coherence length, we identify different states of the gas. In particular, we observe that the gas develops a bimodal distribution

Francesco Buccafurri, Gianluca Caminiti

In everyday life it happens that a person has to reason about what other people think and how they behave, in order to achieve his goals. In other words, an individual may be required to adapt his behaviour by reasoning about the others&#39; mental state. In this paper we focus on a knowledge representation language derived from logic programming which both

A. Botvina, G. Chaudhuri, S. Das Gupta, I. Mishustin

The statistical multifragmentation model (SMM) has been widely used to explain experimental data of intermediate energy heavy ion collisions. A later entrant in the field is the canonical thermodynamic model (CTM) which is also being used to fit experimental data. The basic physics of both the models is the same, namely that fragments are produced according

Waclaw Szymanski

Motivated by importance of operator spaces contained in the set of all scalar multiples of isometries ($MI$-spaces) in a separable Hilbert space for $C^*$-algebras and E-semigroups we exhibit more properties of such spaces. For example, if an $MI$-space contains an isometry with shift part of finite multiplicity, then it is one-dimensional. We propose a simp

Fabio Reale, Salvatore Orlando

Impulsive nanoflares are expected to transiently heat the plasma confined in coronal loops to temperatures of the order of 10 MK. Such hot plasma is hardly detected in quiet and active regions, outside flares. During rapid and short heat pulses in rarified loops the plasma can be highly out of equilibrium of ionization. Here we investigate the effects of the

Federico Bassetti, Lucia Ladelli, Eugenio Regazzini

This paper deals with a one--dimensional model for granular materials, which boils down to an inelastic version of the Kac kinetic equation, with inelasticity parameter $p>0$. In particular, the paper provides bounds for certain distances -- such as specific weighted $χ$--distances and the Kolmogorov distance -- between the solution of that equation and the

A. Mondragon, M. Mondragon, E. Peinado

A variety of lepton flavour violating effects related to the recent discovery of neutrino oscillations and mixings is here systematically discussed in terms of an S_3-flavour permutational symmetry. After presenting some relevant results on lepton masses and mixings, previously derived in a minimal S_3-invariant extension of the Standard Model, we compute th

Alexander Belyaev, Stefan Hesselbach, Sami Lehti, Stefano Moretti

We study the potential of the h_1 -> a_1 a_1 -> 4 tau signal from the lightest scalar (h_1) and pseudoscalar (a_1) Higgs bosons to cover the parameter space of the Next-to-Minimal Supersymmetric Standard Model (NMSSM) at the Large Hadron Collider (LHC). We exploit a 2 mu + 2 jets signature from four taus decays (accompanied by missing transverse energy), res

J. Patience, R. L. Akeson, E. L. N. Jensen

Four Ophiuchus binaries, two Class I systems and two Class II systems, with separations of ~450-1100 AU, were observed with the Owens Valley Radio Observatory (OVRO) millimeter interferometer. In each system, the 3 mm continuum maps show dust emission at the location of the primary star, but no emission at the position of the secondary. This result is differ

Avi M. Mandell, Michael J. Mumma, Goeffrey A. Blake, Boncho P. Bonev

We detect emission from multiple low-excitation ro-vibrational transitions of OH from the two Herbig Ae stars AB Aurigae and MWC 758 in the 3.0 - 3.7 micron wavelength range (L-band), using the NIRSPEC instrument on Keck II. The inner radius for the emitting region in both stars is close to 1 AU. We compare an optically thin LTE model and a thin-wedge fluore

Hakim Atek, Daniel Kunth, Matthew Hayes, Goeran Ostlin

Lyman-alpha is now widely used to investigate the galaxy formation and evolution in the high redshift universe. However, without a rigorous understanding of the processes which regulate the Lya escape fraction, physical interpretations of high-z observations remain questionable. We examine six nearby star-forming galaxies to disentangle the role of the dust

M. Chaichian, K. Nishijima, T. Salminen, A. Tureanu

The concept of a noncommutative field is formulated based on the interplay between twisted Poincaré symmetry and residual symmetry of the Lorentz group. Various general dynamical results supporting this construction, such as the light-wedge causality condition and the integrability condition for Tomonaga-Schwinger equation, are presented. Based on this analy

P. D Klaassen, C. D Wilson

We present maps of seven sources selected from Klaassen & Wilson (2007a) in SiO (J=8-7) and HCO$^+$ and H$^{13}$CO$^+$ (J=4-3) which were obtained using HARP-B on the James Clerk Maxwell Telescope. We find that four out of our seven sources have infall signatures based on their HCO$^+$ emission profiles. From our maps, we have determined the extent of both t

D. Garcia-Sanchez, A. M. van der Zande, A. San Paulo, B. Lassagne

We carried out measurements on nanoelectromechanical systems based on multilayer graphene sheets suspended over trenches in silicon oxide. The motion of the suspended sheets was electrostatically driven at resonance using applied radio-frequency voltages. The mechanical vibrations were detected using a novel form of scanning probe microscopy, which allowed i

Alexander A. Ermolitsky

Some geometric structures with associated Riemannian metrics have been considered in the book.

A. B. Klimov, A. Fernández, C. Muñoz, C. Saavedra

We study the physical implementation of an optimal tomographic reconstruction scheme for the case of determining the state of a multi-qubit system, where trapped ions are used for defining qubits. The protocol is based on the use of mutually unbiased measurements and on the physical information described in H. Häffner \emph{et. al} [Nature \textbf{438}, 643-

J. Walowski, M. Djordjevic Kaufmann, B. Lenk, C. Hamann

The use of femtosecond laser pulses generated by a Ti:Sapphire laser system allows us to gain an insight into the magnetization dynamics on time scales from sub-picosecond up to 1 ns directly in the time domain. This experimental technique is used to excite a polycrystalline nickel (Ni) film optically and probe the dynamics afterwards. Different spin wave mo

Gueorgui Todorov

We prove an analogue of Fujino and Mori&#39;s ``bounding the denominators&#39;&#39; in the log canonical bundle formula (see also Prokhorov and Shokurov) for Kawamata log terminal pairs of relative dimension one. As an application we prove that for a klt pair $(X,Δ)$ of Kodaira codimension one and dimension at most three such that the coefficients of $Δ$ are

Jeremy Marzuola, Andy Miller

A numerical set $S$ with Frobenius number $g$ is a set of integers with $\min(S) = 0$ and $\max(\Zbb - S)=g$, and its atom monoid is $A(S) = \setpres{n \in \Zbb}{$n+s \in S$ for all $s \in S$}$. Let $γ_g$ be the number of numerical sets $S$ having $A(S) = \set{0} \cup (g,\infty)$ divided by the total number of numerical sets with Frobenius number $g$. We sho

Adelchi Fabrocini, Stefano Fantoni, Alexey Yu. Illarionov, Kevin E. Schmidt

S-wave pairing in neutron matter is studied within an extension of correlated basis function (CBF) theory to include the strong, short range spatial correlations due to realistic nuclear forces and the pairing correlations of the Bardeen, Cooper and Schrieffer (BCS) approach. The correlation operator contains central as well as tensor components. The correla

R. Chitra, M. J. Rozenberg

Motivated by the recent experiments on the new spin half Kagome compound ZnCu3(OH)6Cl2, we study a phenomenological model of a frustrated quantum magnet. The model has a spin liquid groundstate and is constructed so as to mimic the macroscopically large quasi-degeneracies expected in the low-lying energy structure of a Kagome system. We use numerical studies

Heide Gluesing-Luerssen, Gert Schneider

A MacWilliams Identity for convolutional codes will be established. It makes use of the weight adjacency matrices of the code and its dual, based on state space realizations (the controller canonical form) of the codes in question. The MacWilliams Identity applies to various notions of duality appearing in the literature on convolutional coding theory.

M. J. Rozenberg, R. Chitra

The recent NMR experiments on ZnCu3(OH)6Cl2 motivate our study of the effect of non- magnetic defects on the antiferromagnetic spin-1/2 kagome lattice. We use exact diagonalization methods to study the effect of two such defects on finite size systems. Our results, obtained without adjustable parameters, are in good quantitative agreement with recent Oxygen

S. A. Stern

We examine the ability of impacts by Kuiper Belt debris to cause regolith exchange between objects in the Pluto system. We find that ejecta velocities from KB impacts are too low to escape from Pluto and Charon. However, ejecta can escape Nix and Hydra, and is capable of covering one another to depths as high as 10s of meters, and Charon and Pluto, perhaps t

S. Bellucci, S. Krivonos, A. Sutulin

We constructed the most general N=4 superconformal 3-particles systems with translation invariance. In the basis with decoupled center of mass the supercharges and Hamiltonian possess one arbitrary function which defines all potential terms. We have shown that with the proper choice of this function one may describe the standard, $A_2$ Calogero model as well

B. Monson, Egon Schulte

When the standard representation of a crystallographic Coxeter group G (with string diagram) is reduced modulo the integer d>1, one obtains a finite group G^d which is often the automorphism group of an abstract regular polytope. Building on earlier work in the case that d is an odd prime, we here develop methods to handle composite moduli and completely des

Andre Sopczak

The importance of collimator R&D with test beam facilities is demonstrated with the example of ILC collimator studies at SLAC End Station A. Related LHC collimator aspects and longer term plans are addressed.

Rafael de la Llave, Nikola P. Petrov

Siegel disks are domains around fixed points of holomorphic maps in which the maps are locally linearizable (i.e., become a rotation under an appropriate change of coordinates which is analytic in a neighborhood of the origin). The dynamical behavior of the iterates of the map on the boundary of the Siegel disk exhibits strong scaling properties which have b

Marianna Bolla, Katalin Friedl, Andras Kramli

Asymptotic behavior of the singular value decomposition (SVD) of blown up matrices and normalized blown up contingency tables exposed to Wigner-noise is investigated.It is proved that such an m\times n matrix almost surely has a constant number of large singular values (of order \sqrt{mn}), while the rest of the singular values are of order \sqrt{m+n} as m,n

Edwige Chapillon, Stéphane Guilloteau, Anne Dutrey, Vincent Piétu

The overall properties of disks surrounding intermediate PMS stars (HAe) are not yet well constrained by current observations. The disk inclination, which significantly affect SED modeling, is often unknown. We attempted to resolve the disks around CQ Tau and MWC 758, to provide accurate constraints on the disk parameters, in particular the temperature and s