August 2010 arXiv papers — page 31

M. A. Leutenegger, P. Beiersdorfer, G. V. Brown, R. L. Kelley

We have measured K-shell x-ray spectra of highly ionized argon and phosphorus following charge exchange with molecular hydrogen at low collision energy in an electron beam ion trap using an x-ray calorimeter array with $\sim$6 eV resolution. We find that the emission at the high-end of the Lyman series is greater by a factor of 2 for phosphorus than for argo

Renan Cabrera, Traci Strohecker, Herschel Rabitz

This paper reveals the relation between the canonical coset decomposition of unitary matrices and the corresponding decomposition via Householder reflections. These results can be used to parametrize unitary matrices via Householder reflections.

D. Dalmazi, Elias L. Mendonça

In $D=2+1$ dimensions there are two dual descriptions of parity singlets of helicity $\pm 1$, namely the self-dual model of first-order (in derivatives) and the Maxwell-Chern-Simons theory of second-order. Correspondingly, for helicity $\pm 2$ there are four models $S_{SD\pm}^{(r)}$ describing parity singlets of helicities $\pm 2$. They are of first-, second

Nicolas Rimbert, Guillaume Castanet

A thorough numerical, theoretical and experimental investigation of the liquid atomization in a full cone pressure swirl nozzle is presented. The first part is devoted to the study of the inner flow. CAD and CFD software are used in order to determine the most important parameters of the flow at the exit of nozzle. An important conclusion is the existence of

Pierre Gosselin, Hervé Mohrbach

We investigate the origin of quantum geometric phases, gauge fields and forces beyond the adiabatic regime. In particular, we extend the notions of geometric magnetic and electric forces discovered in studies of the Born-Oppenheimer approximation to arbitrary quantum systems described by matrix valued quantum Hamiltonians. The results are illustrated by seve

Clément Dombry, Ingemar Kaj

The result provided in this paper helps complete a unified picture of the scaling behavior in heavy-tailed stochastic models for transmission of packet traffic on high-speed communication links. Popular models include infinite source Poisson models, models based on aggregated renewal sequences, and models built from aggregated on-off sources. The versions of

Jacques Touboul

Projection Pursuit methodology permits to solve the difficult problem of finding an estimate of a density defined on a set of very large dimension. In his seminal article, Huber (see "Projection pursuit", Annals of Statistics, 1985) evidences the interest of the Projection Pursuit method thanks to the factorisation of a density into a Gaussian compon

V. Franklin, M. Paramasivam, S. Valarmathi, J. J. H. Miller

A singularly perturbed linear system of second order partial differential equations of parabolic reaction-diffusion type with given initial and boundary conditions is considered. The leading term of each equation is multiplied by a small positive parameter. These singular perturbation parameters are assumed to be distinct. The components of the solution exhi

Mario Koppen, Christiane Tretter, Monika Winklmeier

We consider the spectral problem associated with the Klein-Gordon equation for unbounded electric potentials. If the spectrum of this problem is contained in two disjoint real intervals and the two inner boundary points are eigenvalues, we show that these extremal eigenvalues are simple and possess strictly positive eigenfunctions. Examples of electric poten

D. K. Sinclair, J. B. Kogut

We study QCD with 2 and 3 flavours of colour-sextet quarks. The 2-flavour theory is a candidate Walking Technicolor theory. Since we are attempting to distinguish whether this theory is walking or conformal, we also study the 3-flavour theory, which is believed to be conformal, for comparison. We simulate lattice QCD with 2 and 3 flavours of colour-sextet st

Stephen Semmes

These informal notes are concerned with sums and averages in various situations in analysis.

Elena Poletaeva

We describe the infinitesimal deformations of the standard embedding of the Lie superalgebra $D(2, 1 ; α)$ into the Poisson superalgebra of pseudodifferential symbols on $S^{1|2}$. We show that for the standard embedding of $D(2, 1 ; α)$ into the Poisson superalgebra of differential operators on $S^{1|2}$, the infinitesimal deformations correspond to formal

Nikolaos Kidonakis

I present the latest calculations of total and differential cross sections for top-antitop pair production and single top quark production via all main partonic channels. Higher-order corrections from the resummation of soft gluons are added through NNLL accuracy. Detailed numerical results are presented for approximate NNLO cross sections and top quark tran

Stephen Semmes

These informal notes deal with a number of questions related to sums and integrals in analysis.

Stephen Semmes

This article was prepared in connection with the 2009 Barnett lecture at the University of Cincinnati, and deals with various classes of fractal sets and analysis on them.

V. B. Bobrov, S. A. Trigger, G. J. F. van Heijst

It is shown that the Hohenberg-Kohn lemma and theorem are direct consequences of the statement that the ground state energy (or free energy) of a system of interacting particles in an external field is a unique functional of the potential of this field. This means that, if the Hohenberg-Kohn theorem is valid, the nonuniform density in the equilibrium system

Andrei Iu. Bejan, Gavin J. Gibson, Stan Zachary

We consider problems of Bayesian inference for a spatial epidemic on a graph, where the final state of the epidemic corresponds to bond percolation, and where only the set or number of finally infected sites is observed. We develop appropriate Markov chain Monte Carlo algorithms, demonstrating their effectiveness, and we study problems of optimal experimenta

Irfan Syamsuddin, Tharam Dillon, Elizabeth Chang, Song Han

Security and privacy are the inherent problems in RFID communications. There are several protocols have been proposed to overcome those problems. Hash chain is commonly employed by the protocols to improve security and privacy for RFID authentication. Although the protocols able to provide specific solution for RFID security and privacy problems, they fail t

Z. L. Du, H. N. Wang

The maximum amplitude (Rm) of a solar cycle, in the term of mean sunspot numbers, is well-known to be positively correlated with the preceding minimum (Rmin). So far as the long term trend is concerned, a low level of Rmin tends to be followed by a weak Rm, and vice versa. In this paper, we found that the evidence is insufficient to infer a very weak Cycle 2

Oded Schramm, Scott Sheffield

Consider an instance $h$ of the Gaussian free field on a simply connected planar domain with boundary conditions $-λ$ on one boundary arc and $λ$ on the complementary arc, where $λ$ is the special constant $\sqrt{π/8}$. We argue that even though $h$ is defined only as a random distribution, and not as a function, it has a well-defined zero contour line conne

Kester W. Smith, Coryn A. L. Bailer-Jones, Rainer J. Klement, Xiang-Xiang Xue

We investigate the performance of some common machine learning techniques in identifying BHB stars from photometric data. To train the machine learning algorithms, we use previously published spectroscopic identifications of BHB stars from SDSS data. We investigate the performance of three different techniques, namely k nearest neighbour classification, kern

Anna Carbone, Cecilia Pennetta, Lino Reggiani

A trapping-detrapping model is proposed for explaining the current fluctuation behavior in organic semiconductors (polyacenes) operating under current-injection conditions. The fraction of ionized traps obtained from the current-voltage characteristics, is related to the relative current noise spectral density at the trap-filling transition. The agreement be

Slim Ibrahim, Rym Jrad, Mohamed Majdoub, Tarek Saanouni

We investigate the initial value problem for a semilinear heat equation with exponential-growth nonlinearity in two space dimension. First, we prove the local existence and unconditional uniqueness of solutions in the Sobolev space $H^1(\R^2)$. The uniqueness part is non trivial although it follows Brezis-Cazenave's proof \cite{Br} in the case of monomia

J. B. Marston

Large-scale atmospheric flows may not be so nonlinear as to preclude their statistical description by systematic expansions in cumulants. I extend previous work by examining a two-layer baroclinic model of the general circulation. The fixed point of the cumulant expansion describes the statistically steady state of the out-of-equilibrium model. Equal-time st

Y. Euh, J. H. Park, K. Sekigawa

We give a curvature identity derived from the generalized Gauss-Bonnet formula for 4-dimensional compact oriented Riemannian manifolds. We prove that the curvature identity holds on any 4-dimensional Riemannian manifold which is not necessarily compact. We also provide some applications of the identity.

John J. Horton

This paper reports the results of a series of field experiments designed to investigate how peer effects operate in a real work setting. Workers were hired from an online labor market to perform an image-labeling task and, in some cases, to evaluate the work product of other workers. These evaluations had financial consequences for both the evaluating worker

Charles Frances

We study the set of conformal immersions between two pseudo-Riemannian manifolds of same dimension. We characterize the closure of this set inside the space of continuous maps, and give some geometric consequences when this closure is nonempty.

Vladimir Kulinskii

We analyze the interrelation between the coexistence curve of the Lennard-Jones fluid and the Ising model in two and three dimensions within the global isomorphism approach proposed earlier [V. L. Kulinskii, J. Phys. Chem. B \textbf{114} 2852 (2010)]. In case of two dimensions we use the exact Onsager result to construct the binodal of the corresponding Lenn

Elena Poletaeva

We obtain a realization of the Lie superalgebra $D(2, 1 ; α)$ in differential operators on the supercircle $S^{1|2}$ and in $4\times 4$ matrices over a Weyl algebra. A contraction of $D(2, 1 ; α)$ is isomorphic to the universal central extension $\hat{\p\sł}(2|2)$ of $\p\sł(2|2)$. We realize it in $4\times 4$ matrices over the associative algebra of pseudodi

M. Ali-Akbari, K. Bitaghsir Fadafan

We use the AdS/CFT correspondence to study the DC conductivity of massive $\mathcal{N} = 2$ hypermultiplet fields in an $\mathcal{N} = 4\, SU(N_c)$ super-Yang-Mills theory plasma in the large $N_c$ and finite 't Hooft coupling. We also discuss general curvature-squared and Gauss-Bonnet corrections on the DC conductivity.

Ali A. Orouji, M. Jagadesh Kumar

This paper critically examines the leakage current reduction techniques for improving the performance of poly-Si TFTs used in active matrix liquid crystal displays. This is a first comprehensive study in literature on this topic. The review assesses important proposals to circumvent the leakage current problem in poly-Si TFTs and a short evaluation of streng

Anurag Chaudhry, M. Jagadesh Kumar

This paper examines the performance degradation of a MOS device fabricated on silicon-on-insulator (SOI) due to the undesirable short-channel effects (SCE) as the channel length is scaled to meet the increasing demand for high-speed high-performing ULSI applications. The review assesses recent proposals to circumvent the SCE in SOI MOSFETs and a short evalua

J. van den Berg, M. R. Hilário, Alexander E. Holroyd

In a distributed clustering algorithm introduced by Coffman, Courtois, Gilbert and Piret \cite{coffman91}, each vertex of $\mathbb{Z}^d$ receives an initial amount of a resource, and, at each iteration, transfers all of its resource to the neighboring vertex which currently holds the maximum amount of resource. In \cite{hlrnss} it was shown that, if the dist

Mikhail V. Volkov, Svetlana V. Goldberg, Stanislav I. Kublanovsky

We exhibit a 6-element semigroup that has no finite identity basis but nevertheless generates a variety whose finite membership problem admits a polynomial algorithm.

D. Vogt, P. S. Letelier

An identity that relates multipolar solutions of the Einstein equations to Newtonian potentials of bars with linear densities proportional to Legendre polynomials is used to construct analytical potential-density pairs of infinitesimally thin bars with a given linear density profile. By means of a suitable transformation, softened bars that are free of singu

Lancelot F. James

Exchangeable sequences of random probability measures (partitions of mass) and their corresponding exchangeable bridges play an important role in a variety of areas in probability, statistics and related areas, including Bayesian statistics, physics, finance and machine learning. An area of theoretical as well as practical interest, is the study of coagulati

Denes Petz, Catalin Ghinea

The subject of this paper is a mathematical transition from the Fisher information of classical statistics to the matrix formalism of quantum theory. If the monotonicity is the main requirement, then there are several quantum versions parametrized by a function. In physical applications the minimal is the most popular. There is a one-to-one correspondence be

Weijiang Gong, Hui Li, Guozhu Wei

Electronic transport through a triple-quantum-dot ring with three terminals is theoretically studied. By introducing local Rashba spin-orbit interaction on an individual quantum dot, we find that the spin bias in one terminal drives apparent charge currents in the other terminals, accompanied by the similar amplitude and opposite directions of them. Meanwhil

I. V. Khalzov, F. Ebrahimi, D. D. Schnack, V. V. Mirnov

Axisymmetric relaxed states of a cylindrical plasma column are found analytically in both standard and Hall magnetohydrodynamics (MHD) by complete minimization of energy with constraints imposed by invariants inherent in corresponding models. It is shown that the relaxed state in Hall MHD is the force-free magnetic field with uniform axial flow and/or rigid

Shiwei Wu, Wilson Ho

The junction of a scanning tunneling microscope (STM) operating in the tunneling regime was irradiated with femtosecond laser pulses. A photo-excited hot electron in the STM tip resonantly tunnels into an excited state of a single molecule on the surface, converting it from the neutral to the anion. The electron transfer rate depends quadratically on the inc

Molin Liu, Benhai Yu, Rumin Wang, Lixin Xu

We study the absorption and scattering of massless scalar waves propagating in spherically symmetric spacetimes with dynamical cosmological constant both in low-energy and high-energy zones. In the former low-energy regime, we solve analytically the Regge-Wheeler wave equation and obtain an analytic absorption probability expression which varies with $M\sqrt

Matthew G. Knepley

The Fast Multipole Method (FMM) is well known to possess a bottleneck arising from decreasing workload on higher levels of the FMM tree [Greengard and Gropp, Comp. Math. Appl., 20(7), 1990]. We show that this potential bottleneck can be eliminated by overlapping multipole and local expansion computations with direct kernel evaluations on the finest level gri

Yu-Ping Huang, Joseph B. Altepeter, Prem Kumar

We propose a novel interaction-free scheme for all-optical switching which does not rely on the physical coupling between signal and control waves. The interaction-free nature of the scheme allows it to overcome the fundamental photon-loss limit imposed by the signal-pump coupling. The same phenomenon protects photonic-signal states from decoherence, making

Mayumi Aoki, Shinya Kanemura, Osamu Seto

We discuss phenomenology in a new TeV scale model which would explain neutrino oscillation, dark matter, and baryon asymmetry of the Universe simultaneously by the dynamics of the extended Higgs sector and TeV-scale right-handed neutrinos. Tiny neutrino masses are generated at the three-loop level due to the exact $Z_2$ symmetry, by which the stability of th

H. Sameshima, K. Kawara, Y. Matsuoka, S. Oyabu

We investigate FeII emission in Broad Line Region (BLR) of AGNs by analyzing the FeII(UV), FeII(4570) and MgII emission lines in 884 quasars in the Sloan Digital Sky Survey (SDSS) Quasar catalog in a redshift range of 0.727 < z < 0.804. FeII(4570)/FeII(UV) is used to infer the column density of FeII-emitting clouds and explore the excitation mechanism of FeI

Jungkai Alfred Chen, Christopher D. Hacon

Let $f:X\to Y$ be an algebraic fiber space with general fiber $F$. If $Y$ is of maximal Albanese dimension, we show that $κ(X)\geq κ(Y)+κ(F)$.

David C. Collins, Paolo Padoan, Michael L. Norman, Hao Xu

In this work, we present the mass and magnetic distributions found in a recent Adaptive Mesh Refinement (AMR) MHD simulation of supersonic, \sa, self gravitating turbulence. Powerlaw tails are found in both volume density and magnetic field probability density functions, with $P(ρ) \propto ρ^{-1.67}$ and $P(B)\propto B^{-2.74}$. A power law is also found bet

Hooman Davoudiasl, David E. Morrissey, Kris Sigurdson, Sean Tulin

We present a novel mechanism for generating both the baryon and dark matter densities of the Universe. A new Dirac fermion X carrying a conserved baryon number charge couples to the Standard Model quarks as well as a GeV-scale hidden sector. CP-violating decays of X, produced non-thermally in low-temperature reheating, sequester antibaryon number in the hidd

Jake VanderPlas, Andrew Connolly, Bhuvnesh Jain, Mike Jarvis

We present a new method for constructing three-dimensional mass maps from gravitational lensing shear data. We solve the lensing inversion problem using truncation of singular values (within the context of generalized least squares estimation) without a priori assumptions about the statistical nature of the signal. This singular value framework allows a quan

Chong Gyu Lee

A polarizable endomorphism on a projective variety enables us to consider given morphism as constant multiplication in the height function. In this paper, we will generalize it for arbitrary dominant endomorphism by defining the height expansion and contraction coefficients.

Hang Dinh, Cristopher Moore, Alexander Russell

Quantum computers can break the RSA and El Gamal public-key cryptosystems, since they can factor integers and extract discrete logarithms. If we believe that quantum computers will someday become a reality, we would like to have \emph{post-quantum} cryptosystems which can be implemented today with classical computers, but which will remain secure even in the

E. M. Shahverdiev, P. A. Bayramov, K. A. Shore

We study a model for two lasers that are mutually coupled opto-electronically by modulating the pump of one laser with the intensity deviations from the steady-state output of the other. Such a model is analogous to the equations describing the spread of certain diseases such as dengue epidemics in human populations coupled by migration, transportation, etc.

Jacqueline Chen, Savvas M. Koushiappas

We investigate the feasibility of extracting the gravitational nanolensing signal due to the presence of subsolar mass halos within galaxy-sized dark matter halos. We show that subsolar mass halos in a lensing galaxy can cause strong nanolensing events with shorter durations and smaller amplitudes than microlensing events caused by stars. We develop techniqu

Juna A. Kollmeier, Andrew Gould, Constance Rockosi, Timothy C. Beers

We present new limits on the ejection of metal-rich old-population hypervelocity stars from the Galactic center (GC) as probed by the SEGUE-2 survey. Our limits are a factor of 3-10 more stringent than previously reported, depending on stellar type. Compared to the known population of B-star ejectees, there can be no more than 30 times more metal-rich old-po

Laura A. Lopez, Mark R. Krumholz, Alberto D. Bolatto, J. Xavier Prochaska

Observations show that star formation is an inefficient and slow process. This result can be attributed to the injection of energy and momentum by stars that prevents free-fall collapse of molecular clouds. The mechanism of this stellar feedback is debated theoretically: possible sources of pressure include the classical warm HII gas, the hot gas generated b

Wayne M. Witzel, Malcolm S. Carroll, Andrea Morello, Lukasz Cywinski

Silicon is promising for spin-based quantum computation because nuclear spins, a source of magnetic noise, may be eliminated through isotopic enrichment. Long spin decoherence times, $T_2$, have been measured in isotope-enriched silicon but come far short of the $T_2 = 2 T_1$ limit. The effect of nuclear spins on $T_2$ is well established. However, the effec

N. A. Carella

Assuming the Riemann hypothesis, this article discusses a new elementary argument that seems to prove that the maximal prime gap of a finite sequence of primes p_1, p_2, ..., p_n <= x, satisfies max {p_(n+1) - p_n : p_n <= x} <= c1((logx)^2)/loglogx, c1 > 0 constant. Equivalently, it shows that the very short intervals (x, x + y] contain prime numbers for al

Brian Harbourne, Hal Schenck, Alexandra Seceleanu

Migliore-Miró-Roig-Nagel [Trans. A.M.S. 2011, arXiv: 0811.1023] show that the weak Lefschetz property (WLP) can fail for an ideal I in K[x_1,x_2,x_3,x_4] generated by powers of linear forms. This is in contrast to the analogous situation in K[x_1,x_2,x_3], where WLP always holds [H.Schenck, A.Seceleanu, Proc. A.M.S. 2010, arXiv:0911.0876]. We use the inverse

G. Cordourier-Maruri, F. Ciccarello, Y. Omar, M. Zarcone

We investigate whether a two-qubit quantum gate can be implemented in a scattering process involving a flying and a static qubit. To this end, we focus on a paradigmatic setup made out of a mobile particle and a quantum impurity, whose respective spin degrees of freedom couple to each other during a one-dimensional scattering process. Once a condition for th

Alain Couvreur

In the present article, we consider Algebraic Geometry codes on some rational surfaces. The estimate of the minimum distance is translated into a point counting problem on plane curves. This problem is solved by applying the upper bound &#34;à la Weil&#34; of Aubry and Perret together with the bound of Homma and Kim for plane curves. The parameters of severa

Ashutosh Kumar Alok, Alakabha Datta, Amol Dighe, Murugeswaran Duraisamy

We perform a comprehensive study of the impact of new-physics operators with different Lorentz structures on decays involving the b -> s mu+ mu- transition. We examine the effects of new vector-axial vector (VA), scalar-pseudoscalar (SP) and tensor (T) interactions on the differential branching ratios and forward-backward asymmetries (A_{FB}&#39;s) of Bsbar

Michael Levitin, Dmitri Vassiliev

This is the editors' preface to the volume "Operator theory and its applications, in memory of V. B. Lidskii (1924-2008)". The volume was published by the American Mathematical Society in the series AMS Translations, series 2, volume 231 (2010).

W. Buchmuller, K. Schmitz, G. Vertongen

We study tachyonic preheating associated with the spontaneous breaking of B-L, the difference of baryon and lepton number. Reheating occurs through the decays of heavy Majorana neutrinos which are produced during preheating and in decays of the Higgs particles of B-L breaking. Baryogenesis is an interplay of nonthermal and thermal leptogenesis, accompanied b

V. Gonzalez-Perez, F. J. Castander, G. Kauffmann

The evolutionary path followed by a galaxy shapes its internal structure, and, in particular, its internal colour variation. We present a study of the internal colour variation within galaxies from the Seventh Data Release of the Sloan Digital Sky Survey (SDSS DR7). We statistically study the connection between the internal colour variation and global galact

Gordon Blower

Let v be a real polynomial of even degree, and let \rho be the equilibrium probability measure for v with support S; so that v(x)\geq 2\int \log |x-y| \rho (dy)+C_v for some constant C_v with support S. Then S is the union of finitely many bounded intervals with endpoints delta_j, and \rho is given by an algebrais weight w(x) on S. The system of orthogonal p

Yi-Zhi Huang

Let $V$ be a grading-restricted vertex algebra and $W$ a $V$-module. We show that for any $m\in \mathbb{Z}_{+}$, the first cohomology $H^{1}_{m}(V, W)$ of $V$ with coefficients in $W$ introduced by the author is linearly isomorphic to the space of derivations from $V$ to $W$. In particular, $H^{1}_{m}(V, W)$ for $m\in \mathbb{N}$ are equal (and can be denote

Eddye Bustamante, Pedro Isaza, Jorge Mejía

In this article we prove that sufficiently smooth solutions of the Zakharov-Kuznetsov equation that have compact support for two different times are identically zero.

A. B. Orue, G. Alvarez, A. Guerra, G. Pastor

This article describes a new family of cryptographically secure pseudorandom number generators, based on coupled chaotic maps, that will serve as keystream in a stream cipher. The maps are a modification of a piecewise linear map, by dynamic changing of the coefficient values and perturbing its lesser significant bits.

Alberto Favaro, Luzi Bergamin

Based on a recent work by Schuller et al., a geometric representation of all skewonless, non-birefringent, linear media is obtained. The derived constitutive law is based on a &#34;core&#34;, encoding the optical metric up to a constant. All further corrections are provided by two (anti-)selfdual bivectors, and an &#34;axion&#34;. The bivectors are found to

Jan-Hendrik Evertse, Roberto G. Ferretti

In 2002, Evertse and Schlickewei obtained a quantitative version of the so-called Absolute Parametric Subspace Theorem. This result deals with a parametrized class of twisted heights. One of the consequences of this result is a quantitative version of the Absolute Subspace Theorem, giving an explicit upper bound for the number of subspaces containing the sol

Nick Devereux, Michael Eracleous, Paul Hriljac, Andrew Shearer

M84 is a giant elliptical galaxy located in the Virgo cluster. Prior imaging with the Hubble Space Telescope (HST) revealed a small, highly inclined, nuclear ionized gas disk, the kinematics of which indicate the presence of a 0.4 -1.5 billion solar mass black hole. Two prominent radio jets emerge perpendicular to the nuclear ionized gas disk terminating in

Bjoern Baeuchle, Marcus Bleicher

The microscopic transport model UrQMD and a micro+macro hybrid model are used to calculate direct photon spectra from U+U-collisions at Elab = 35 AGeV as will be measured by the CBM-collaboration at FAIR. In the hybrid model, the intermediate high-density part of the nuclear interaction is described with ideal 3+1-dimensional hydrodynamics. Different equatio

Luca Mezincescu, Paul K. Townsend

The Nambu-Goto string in a 3-dimensional (3D) Minkowski spacetime is quantized preserving Lorentz invariance and parity. The spectrum of massive states contains anyons. An ambiguity in the ground state energy is resolved by the 3D N=1 Green-Schwarz superstring, which has massless ground states describing a dilaton and dilatino, and first-excited states of sp

A. T. Filippov

We discuss new models of an `affine&#39; theory of gravity in multidimensional space-times with symmetric connections. We use and develop ideas of Weyl, Eddington, and Einstein, in particular, Einstein&#39;s proposal to specify the space - time geometry by use of the Hamilton principle. More specifically, the connection coefficients are determined using a `g

John Cardy

I discuss various aspects of the role of the conformal anomaly number c in 2- and 1+1-dimensional critical behaviour: its appearance as the analogue of Stefan&#39;s constant, its fundamental role in conformal field theory, in the classification of 2d universality classes, and as a measure of quantum entanglement, among other topics.

M. Alvioli, M. Strikman

We develop a new approach to production of the spectator nucleons in the heavy ion collisions. The energy transfer to the spectator system is calculated using the Monte Carlo based on the updated version of our generator of configurations in colliding nuclei which includes a realistic account of short-range correlations in nuclei. The transferred energy dist

Paola Gori-Giorgi, Michael Seidl

Improving the accuracy and thus broadening the applicability of electronic density functional theory (DFT) is crucial to many research areas, from material science, to theoretical chemistry, biophysics and biochemistry. In the last three years, the mathematical structure of the strong-interaction limit of density functional theory has been uncovered, and exa

Efrat Shimshoni, Giovanna Morigi, Shmuel Fishman

A string of trapped ions at zero temperature exhibits a structural phase transition to a zigzag structure, tuned by reducing the transverse trap potential or the interparticle distance. The transition is driven by transverse, short wavelength vibrational modes. We argue that this is a quantum phase transition, which can be experimentally realized and probed.

Thorsten Wengler

The ATLAS experiment has been taking data efficiently since LHC collisions started, first at the injection energy of 450 GeV/beam and at 1.18 TeV/beam in 2009, then at 3.5 TeV/beam in 2010. Many results have already been obtained based on this data demonstrating the performance of the detector, as well as first physics measurements. Only a selection of highl

Tomasz Świsłocki, Tomasz Sowiński, Mirosław Brewczyk, Mariusz Gajda

We study a square plaquette of four optical microtraps containing ultracold $^{87}$Rb atoms in F=1 hyperfine state. In a presence of external resonant magnetic field the dipolar interactions couple initial $m_F=1$ component to other Zeeman sublevels. This process is a generalization of the Einstein-de Haas effect to the case when the external potential has o

S. V. Molodtsov, G. M. Zinovjev

Some features of hot and dense gas of quarks which are considered as the quasi-particles of the model Hamiltonian with four-fermion interaction are studied. Being adapted to the Nambu-Jona-Lasinio model this approach allows us to accommodate a phase transition similar to the nuclear liquid-gas one at the proper scale. It allows us to argue an existence of th

Frank Simon

The CALICE collaboration has constructed highly granular electromagnetic and hadronic calorimeter prototypes to evaluate technologies for the use in detector systems at a future Linear Collider. The hadron calorimeter uses small scintillator cells individually read out with silicon photomultipliers. The system with 7608 channels has been successfully operate

Wojciech Broniowski, Enrique Ruiz Arriola

We explore the BaBar puzzle within the Regge approach. After reviewing the chiral quark models in applications to PDF and PDA of the pion, we argue that variants of these models, fulfilling the chiral anomaly, may in fact violate the second Terazawa-West unitarity bound, which is based on unverified assumptions for the real part of the amplitude. Consequentl

Rachael M. Kratzer, Gordon T. Richards, David M. Goldberg, Masamune Oguri

Using a high resolution radio image, we successfully resolve the two fold image components B and C of the quasar lens system SDSS J1029+2623. The flux anomalies associated with these two components in the optical regime persist, albeit less strongly, in our radio observations, suggesting that the cluster must be modeled by something more than a single centra

J. S. Klar, J. P. Mücket

Numerical simulations predict a considerable fraction of the missing baryons at redshift z ~ 0 resting in the so called warm-hot intergalactic medium (WHIM). The filaments and sheets of the WHIM have high temperatures 10^5 - 10^7 K) and a high degree of ionization while having only low to intermediate densities. The particular physical conditions of the WHIM

Sunil Chhita

We study a low temperature anisotropic anti-ferromagnetic 2D Ising model through the guise of a certain dimer model. This model has a bijection with a one-dimensional particle system equipped with creation and annihilation. In the thermodynamic limit, we determine the explicit phase diagrams as functions of temperature and anisotropy. Two values of the aniso

Jochen Zahn

We study quantum electrodynamics on the noncommutative Minkowski space in the Yang-Feldman formalism. Local observables are defined by using covariant coordinates. We compute the two-point function of the interacting field strength to second order and find the infrared divergent terms already known from computations using the so-called modified Feynman rules

Motoi Endo, Koichi Hamaguchi, Kouhei Nakaji

We investigate the possibility of probing high reheating temperature scenarios at the LHC, in supersymmetric models where the gravitino is the lightest supersymmetric particle, and the stau is the next-to-lightest supersymmetric particle. In such scenarios, the big-bang nucleosynthesis and the gravitino abundance give a severe upper bound on the gluino mass.

John Fuini, Nasser S. Demir, Dinesh K. Srivastava, Steffen A. Bass

Among the key features of hot and dense QCD matter produced in ultra-relativistic heavy-ion collisions at RHIC is its very low shear viscosity, indicative of the properties of a near-ideal fluid, and a large opacity demonstrated by jet energy loss measurements. In this work, we utilize a microscopic transport model based on the Boltzmann equation with quark

E. G. Highcock, M. Barnes, A. A. Schekochihin, F. I. Parra

The effect of flow shear on turbulent transport in tokamaks is studied numerically in the experimentally relevant limit of zero magnetic shear. It is found that the plasma is linearly stable for all non-zero flow shear values, but that subcritical turbulence can be sustained nonlinearly at a wide range of temperature gradients. Flow shear increases the nonli

Devranjan Samanta, Alberto de Lozar, Bjoern Hof

In shear flows turbulence first occurs in the form of localized structures (puffs/spots) surrounded by laminar fluid. We here investigate such spatially intermittent flows in a pipe experiment showing that turbulent puffs have a well defined interaction distance, which sets the minimum spacing of puffs as well as the maximum observable turbulent fraction. Tw

Scott A. Wolpert

An expansion is developed for the Weil-Petersson Riemann curvature tensor in the thin region of the Teichmüller and moduli spaces. The tensor is evaluated on the gradients of geodesic-lengths for disjoint geodesics. A precise lower bound for sectional curvature in terms of the surface systole is presented. The curvature tensor expansion is applied to establi

Lucio Cerrito

We present preliminary measurements of $Z/\gamma^*$+jets, $W+c$ and $Z+b+X$ at the Tevatron, and review recent measurements of vector boson plus inclusive and heavy-flavor jets production. All measurements are in agreement with next-to-leading-order QCD calculations within the experimental and theoretical uncertainties. We also point to comparisons of the pr

David Tsiklauri

1.5D Vlasov-Maxwell simulations are employed to model electromagnetic emission generation in a fully self-consistent plasma kinetic model for the first time in the solar physics context. The simulations mimic the plasma emission mechanism and Larmor drift instability in a plasma thread that connects the Sun to Earth with the spatial scales compressed appropr

Robin John, A Ashokreddy, C Vijayan, T Pradeep

Steeping interest on graphene research in basic sciences and applications emphasizes the need for an economical means of synthesizing it. We report a method for the synthesis of graphene on commercially available stainless steel foils using direct thermal chemical vapor deposition. Our method of synthesis and the use of relatively cheap precursors such as et

Annalisa Cerquetti

We introduce a new parametrization for the two-parameter species sampling model with {\it finite} but {\it random} number of different species recently introduced in Gnedin (2010a). We show the reparametrization yields a representation in terms of generalized Waring mixture of Fisher species sampling models and derive the structural distribution of the model

Tudor S. Ratiu, Madeleine Jotz

The purpose of this paper is to generalize the regular Optimal Reduction Theorem to general proper Dirac actions, formulated both in terms of point and orbit reduction. A comparison to general standard singular Dirac reduction is given emphasizing the desingularization role played by optimal reduction.

Tudor S. Ratiu, Madeleine Jotz

A new method of singular reduction is extended from Poisson to Dirac manifolds. Then it is shown that the Dirac structures on the strata of the quotient coincide with those of the only other known singular Dirac reduction method.

Alexander Schnurr

Let U be an open set in R^d. We show that under a mild assumption on the richness of the generator a Feller process in U with (predictable) killing is a semimartingale. To this end we generalize the notion of semimartingales in a natural way to those &#39;with killing&#39;. Furthermore we calculate the semimartingale characteristics of the Feller process exp

L. Rondin, G. Dantelle, A. Slablab, F. Grosshans

We present a study of the charge state conversion of single nitrogen-vacancy (NV) defects hosted in nanodiamonds (NDs). We first show that the proportion of negatively-charged NV$^{-}$ defects, with respect to its neutral counterpart NV$^{0}$, decreases with the size of the ND. We then propose a simple model based on a layer of electron traps located at the