March 2008 arXiv papers — page 41

Nancy E. Clarke, Samuel Fiorini, Gwenaël Joret, Dirk Oliver Theis

The Cops and Robber game is played on undirected finite graphs. A number of cops and one robber are positioned on vertices and take turns in sliding along edges. The cops win if they can catch the robber. The minimum number of cops needed to win on a graph is called its cop number. It is known that the cop number of a graph embedded on a surface $X$ of genus

R. Martinez-Casado, A. S. Sanz, S. Miret-Artes

A quantum Markovian activated atom-surface diffusion model with interacting adsorbates is proposed for the intermediate scattering function, which is shown to be complex-valued and factorizable into a classical-like and a quantum-mechanical factor. Applications to the diffusion of Na atoms on flat (weakly corrugated) and corrugated-Cu(001) surfaces at differ

Ji Oon Lee

It is well known that the ground state energy of a three dimensional dilute Bose gas in the thermodynamic limit is $E=4πa ρN$ when the particles interact via a non-negative, finite range, symmetric, two-body potential. Here, $N$ is the number of particles, $ρ$ is the density of the gas, and $a$ is the scattering length of the potential. In this paper, we pro

Bogdan A. Dobrescu, Andreas S. Kronfeld

The measured rate for D_s -> l nu decays, where l is a muon or tau, is larger than the standard model prediction, which relies on lattice QCD, at the 3.8 sigma level. We discuss how robust the theoretical prediction is, and we show that the discrepancy with experiment may be explained by a charged Higgs boson or a leptoquark.

S. M. Bilenky, F. von Feilitzsch, W. Potzel

Using the Mandelstam-Tamm method we derive time-energy uncertainty relations for neutrino oscillations. We demonstrate that the small energy uncertainty of antineutrinos in a recently considered experiment with recoilless resonant (Mössbauer) production and absorption of tritium antineutrinos is in conflict with the energy uncertainty which, according to the

Christoph Luhn, Pierre Ramond

We construct all quintic invariants in five variables with simple Non-Abelian finite symmetry groups. These define Calabi-Yau three-folds which are left invariant by the action of A_5, A_6 or PSL_2(11).

Mehmet B. Oktay, Andreas S. Kronfeld

We extend the Fermilab method for heavy quarks to include interactions of dimensions 6 and 7 in the action. There are, in general, many new interactions, but we carry out the calculations needed to match the lattice action to continuum QCD at the tree level, finding six non-zero couplings. Using the heavy-quark theory of cutoff effects, we estimate how large

Corrado Mascia, Kevin Zumbrun

Using a combination of Kawashima- and Goodman-type energy estimates, we establish spectral stability of general small-amplitude relaxation shocks of symmetric dissipative systems. This extends previous results obtained by Plaza and Zumbrun by singular perturbation techniques under an additional technical assumption, namely, that the background equation be no

A. Amariti, D. Forcella, L. Girardello, A. Mariotti

We study the geometric interpretation of metastable vacua for systems of D3 branes at non isolated toric deformable singularities. Using the L^{aba} examples, we investigate the relations between the field theoretic susy breaking and restoration and the complex deformations of the CY singularities.

Y. G. Tsamis, J. M. C. Rawlings, J. A. Yates, S. Viti

The evolution of star-forming core analogues undergoing inside-out collapse is studied with a multi-point chemodynamical model which self-consistently computes the abundance distribution of chemical species in the core. For several collapse periods the output chemistry of infall tracer species such as HCO+, CS, and N2H+, is then coupled to an accelerated Lam

J. Feist, S. Nagele, R. Pazourek, E. Persson

We present accurate time-dependent ab initio calculations on fully differential and total integrated (generalized) cross sections for the nonsequential two-photon double ionization of helium at photon energies from 40 to 54 eV. Our computational method is based on the solution of the time-dependent Schroedinger equation and subsequent projection of the wave

Hanno Essen

We calculate the energy of a homogeneous one component plasma and find that the energy is lower for correlated motions of the particles as compared to uncorrelated motion. Our starting point is the conserved approximately relativistic (Darwin) energy for a system of electromagnetically interacting particles that arises from the neglect of radiation. For the

Howard Baer, Heaya Summy

Simple SUSY GUT models based on the gauge group SO(10) require t-b-τYukawa coupling unification, in addition to gauge coupling and matter unification. The Yukawa coupling unification places strong constraints on the expected superparticle mass spectrum, with scalar masses \sim 10 TeV while gaugino masses are quite light. A problem generic to all supergravity

Iacopo Carusotto, Serena Fagnocchi, Alessio Recati, Roberto Balbinot

We report numerical evidence of Hawking emission of Bogoliubov phonons from a sonic horizon in a flowing one-dimensional atomic Bose-Einstein condensate. The presence of Hawking radiation is revealed from peculiar long-range patterns in the density-density correlation function of the gas. Quantitative agreement between our fully microscopic calculations and

H. Reinhardt

It is shown that the inverse of the ghost form factor in the Hamilton approach to Yang-Mills theory in Coulomb gauge can be interpreted as the color dielectric function of the QCD vacuum. Furthermore the horizon condition to the ghost form factor implies that in the infrared the QCD vacuum is a perfect color diaelectric medium and therefore a dual supercondu

Cornelia A. Van Cott

We study the behavior of the Ozsvath-Szabo and Rasmussen knot concordance invariants tau and s on K(m,n), the (m,n)-cable of a knot K where m and n are relatively prime. We show that for every knot K and for any fixed positive integer m, both of the invariants evaluated on K(m,n) differ from their value on the torus knot T(m,n) by a fixed constant for all bu

Rupert L. Frank, Robert Seiringer

We determine the sharp constant in the Hardy inequality for fractional Sobolev spaces. To do so, we develop a non-linear and non-local version of the ground state representation, which even yields a remainder term. From the sharp Hardy inequality we deduce the sharp constant in a Sobolev embedding which is optimal in the Lorentz scale. In the appendix, we ch

Zhiqin Lu

In this paper, we proved the Normal Scalar Curvature Conjecture and the Bottcher-Wenzel Conjecture. We also established some new pinching theorems for minimal submanifolds in spheres.

J. L. Prieto, M. D. Kistler, T. A. Thompson, H. Yuksel

We report the discovery of the progenitor of the recent type IIn SN 2008S in the nearby galaxy NGC 6946. Surprisingly, it was not found in deep, pre-explosion optical images of its host galaxy taken with the Large Binocular Telescope, but only through examination of archival Spitzer mid-IR data. A source coincident with the SN 2008S position is clearly detec

Satoshi Okuzumi, Kunihito Ioka, Masa-aki Sakagami

We investigate the nonlinear evolution of black hole ringdown in the framework of higher-order metric perturbation theory. By solving the initial-value problem of a simplified nonlinear field model analytically as well as numerically, we find that (i) second-order quasinormal modes (QNMs) are indeed excited at frequencies different from those of first-order

P. Johnson, R. Pandharipande, H. -H. Tseng

Hodge classes on the moduli space of admissible covers with monodromy group G are associated to irreducible representations of G. We evaluate all linear Hodge integrals over moduli spaces of admissible covers with abelian monodromy in terms of multiplication in an associated wreath group algebra. In case G is cyclic and the representation is faithful, the ev

A. Feigel

A major obstacle in analyzing the evolution of information exchange and processing is our insufficient understanding of the underlying signaling and decision-making biological mechanisms. For instance, it is unclear why are humans unique in developing such extensive communication abilities. To treat this problem, a method based on the mutual information appr

Marek Gierlinski, Chris Done, Kim Page

The key aspect of the very successful truncated disc model for the low/hard X-ray spectral state in black hole binaries is that the geometrically thin disc recedes back from the last stable orbit at the transition to this state. This has recently been challenged by direct observations of the low/hard state disc from CCD data. We reanalyze the Swift and RXTE

Yasaman Farzan, Alexei Yu Smirnov

For cosmic neutrinos we study the conditions and the effects of the coherence loss as well as coherent broadening of the spectrum. We evaluate the width of the neutrino wavepacket produced by charged particles under various circumstances: in an interaction-free environment, in a radiation-dominated medium (typical of the sources of the gamma ray bursts) and

Tao Hu, B. I. Shklovskii

Translocation of a single stranded DNA through genetically engineered $α$-hemolysin channels with positively charged walls is studied. It is predicted that transport properties of such channels are dramatically different from neutral wild type $α$-hemolysin channel. We assume that the wall charges compensate the fraction $x$ of the bare charge $q_{b}$ of the

Mahir Bilen Can, Lex E. Renner

The rook monoid $R_n$ is the finite monoid whose elements are the 0-1 matrices with at most one nonzero entry in each row and column. The group of invertible elements of $R_n$ is isomorphic to the symmetric group $S_n$. The natural extension to $R_n$ of the Bruhat-Chevalley ordering on the symmetric group is defined in \cite{Renner86}. In this paper, we find

A. Abada, C. Biggio, F. Bonnet, M. B. Gavela

In the framework of the seesaw models with triplets of fermions, we evaluate the decay rates of $μ\to e γ$ and $τ\to l γ$ transitions. We show that although, due to neutrino mass constraints, those rates are in general expected to be well under the present experimental limits, this is not necessarily always the case. Interestingly enough, the observation of

Alessandro Cafarella, Claudio Coriano, Marco Guzzi

We summarize the theoretical approach to the solution of the NNLO DGLAP equations using methods based on the logarithmic expansions in x-space and their implementation into the C program Candia 1.0. We present the various options implemented in the program and discuss the different solutions. The user can choose the order of the evolution, the type of the so

Z. Bern, S. Dittmaier, L. Dixon, G. Heinrich

This report summarizes the activities of the NLM working group of the Workshop "Physics at TeV Colliders", Les Houches, France, 11-29 June, 2007.

Alessio Filippetti, Giorgia M. Lopez, Mauro Mantega, Vincenzo Fiorentini

We describe from advanced first principles calculations the energetics of oxygen doping and its relation to insulator-metal transitions in underdoped YBa$_2$Cu$_3$O$_{6+x}$. We find a strong tendency of doping oxygens to order into non-magnetic Cu$^{1+}$O$_x$ chains at any $x$. Ordering produces one-dimensional metallic bands, while configurations with non-a

Leonardo Biliotti, Miguel Angel Javaloyes

In this paper we prove several multiplicity results of $t$-periodic light rays in conformally stationary spacetimes using the Fermat metric and the extensions of the classical theorems of Gromoll-Meyer and Bangert-Hingston to Finsler manifolds. Moreover, we exhibit some stationary spacetimes with a finite number of $t$-periodic light rays and compute a lower

Dong Wang, Tony Hansson, Asa Larson, Hans O. Karlsson

We apply wave packet methods to study an ion-trap system in the strong excitation regime imposing neither the rotating wave nor the Lamb-Dicke approximations. By this approach we show the existence of states with restricted phase space evolution, as a genuine consequence of quantum interference between wave packet fractions. A particular instance of such a s

B. Dierckx, M. Fannes, C. Vandenplas

We prove that the minimal Renyi entropy of order 2 (RE2) output of a positive-partial-transpose(PPT)-inducing channel joint to an arbitrary other channel is equal to the sum of the minimal RE2 output of the individual channels. PPT-inducing channels are channels with a Choi matrix which is bound entangled or separable. The techniques used can be easily recyc

H. Fujii, K. Itakura

We present an analytic study of the physics of the glasma which is a strong classical gluon field created at early stage of high-energy heavy-ion collisions. Our analysis is based on the picture that the glasma just after the collision is made of color electric and magnetic flux tubes extending in the longitudinal direction with their diameters of the order

R. H. Sanders, D. D. Land

Bolton et al. (2007) have derived a mass-based fundamental plane using photometric and spectroscopic observations of 36 strong gravitational lenses. The lensing allows a direct determination of the mass-surface density and so avoids the usual dependence on mass-to-light ratio. We consider this same sample in the context of modified Newtonian dynamics (MOND)

Vincent D. Blondel, Jean-Loup Guillaume, Renaud Lambiotte, Etienne Lefebvre

We propose a simple method to extract the community structure of large networks. Our method is a heuristic method that is based on modularity optimization. It is shown to outperform all other known community detection method in terms of computation time. Moreover, the quality of the communities detected is very good, as measured by the so-called modularity.

Sergio Dain, Carlos O. Lousto, Yosef Zlochower

We evolve equal-mass, equal-spin black-hole binaries with specific spins of a/mH 0.925, the highest spins simulated thus far and nearly the largest possible for Bowen-York black holes, in a set of configurations with the spins counter-aligned and pointing in the orbital plane, which maximizes the recoil velocities of the merger remnant, as well as a configur

Edith Cohen, Nick Duffield, Haim Kaplan, Carsten Lund

From a high volume stream of weighted items, we want to maintain a generic sample of a certain limited size $k$ that we can later use to estimate the total weight of arbitrary subsets. This is the classic context of on-line reservoir sampling, thinking of the generic sample as a reservoir. We present an efficient reservoir sampling scheme, $\varoptk$, that d

A. Vinante, M. Bignotto, M. Bonaldi, M. Cerdonio

We apply a feedback cooling technique to simultaneously cool the three electromechanical normal modes of the ton-scale resonant-bar gravitational wave detector AURIGA. The measuring system is based on a dc Superconducting Quantum Interference Device (SQUID) amplifier, and the feedback cooling is applied electronically to the input circuit of the SQUID. Start

Thomas Becher, Matthew D. Schwartz

Starting from a factorization theorem in Soft-Collinear Effective Theory, the thrust distribution in e+e- collisions is calculated including resummation of the next-to-next-to-next-to leading logarithms. This is a significant improvement over previous calculations which were only valid to next-to-leading logarithmic order. The fixed-order expansion of the re

R. K. Rakshit, S. K. Bose, R. Sharma, N. K. Pandey

The effect of strain due to lattice mismatch and of ferromagnetic (FM) exchange field on superconductivity (SC) in NbN-CoPt bilayers is investigated. Two different bilayer systems with reversed deposition sequence are grown on MgO (001) single crystals. While robust superconductivity with high critical temperature (T_c ~ 15.3 K) and narrow transition width D

Mohsen Asgharzadeh, Kamran Divaani-Aazar, Massoud Tousi

Let \fa be an ideal of a commutative Noetherian ring R and M a finitely generated R-module. We explore the behavior of the two notions f_{\fa}(M), the finiteness dimension of M with respect to \fa, and, its dual notion q_{\fa}(M), the Artinianess dimension of M with respect to \fa. When (R,\fm) is local and r:=f_{\fa}(M) is less than f_{\fa}^{\fm}(M), the \f

S. Moch

We review the status of QCD at hadron colliders with emphasis on precision predictions and the latest theoretical developments for cross sections calculations to higher orders. We include an overview of our current information on parton distributions and discuss various Standard Model reactions such as W/Z-boson, Higgs boson or top quark production.

Minos A. Neto, Jürgen F. Stilck

We consider the entropy of polydisperse chains placed on a lattice. In particular, we study a model for equilibrium polymerization, where the polydispersivity is determined by two activities, for internal and endpoint monomers of a chain. We solve the problem exactly on a Bethe lattice with arbitrary coordination number, obtaining an expression for the entro

Ivan Nourdin, Giovanni Peccati

We show how to detect optimal Berry--Esseen bounds in the normal approximation of functionals of Gaussian fields. Our techniques are based on a combination of Malliavin calculus, Stein's method and the method of moments and cumulants, and provide de facto local (one-term) Edgeworth expansions. The findings of the present paper represent a further refinem

Christian Engstrom, Markus Richter

We study wave propagation in periodic and frequency dependent materials. The approach in this paper leads to spectral analysis of a quadratic operator pencil where the spectral parameter relates to the quasimomentum and the frequency is a parameter. We show that the underlying operator has a discrete spectrum, where the eigenvalues are symmetrically placed w

Lihui Liu, Bin Wang

We study the dynamical stability of the BTZ black string against fermonic and gravitational perturbations. The BTZ black string is not always stable against these perturbations. There exist threshold values for $m^2$ related to the compactification of the extra dimension for fermonic perturbation, scalar part of the gravitational perturbation and the tensor

Yoshimasa Hidaka, Robert D. Pisarski

We consider QCD at temperatures T near Tc, where the theory deconfines. We distinguish between a "complete" Quark Gluon Plasma (QGP), where the vacuum expectation value of the renormalized Polyakov loop is near unity, essentially constant with T, and the "semi"-QGP, where the loop changes strongly with T. Lattice simulations indicate that in

Grigori G. Amosov, Stefano Mancini

We argue that a fundamental (conjectured) property of memoryless quantum channels, namely the strong superadditivity, is intimately related to the decreasing property of the quantum relative entropy. Using the latter we first give, for a wide class of input states, an estimation of the output entropy for phase damping channels and some Weyl quantum channels.

Lior Bary-Soroker

The main goal of this work is to answer a question of P. D`ebes and D. Haran by relaxing the condition for Hilbertianity. Namely we prove that for a field K to be Hilbertian it suffices that K has the irreducible specialization property merely for absolutely irreducible polynomials.

Debprakash Patnaik, P. S. Sastry, K. P. Unnikrishnan

Understanding the functioning of a neural system in terms of its underlying circuitry is an important problem in neuroscience. Recent developments in electrophysiology and imaging allow one to simultaneously record activities of hundreds of neurons. Inferring the underlying neuronal connectivity patterns from such multi-neuronal spike train data streams is a

Patrick Clarke

We introduce a duality construction for toric Landau-Ginzburg models, applicable to complete intersections in toric varieties via the sigma model / Landau-Ginzburg model correspondence. This construction is shown to reconstruct those of Batyrev-Borisov, Berglund-H"ubsch, Givental, and Hori-Vafa. It can be done in more general situations, and provides par

Emil Avsar

In this paper we perform a numerical study of the tranverse expansion of hadronic scattering amplitudes in the dipole picture of high energy QCD. We go beyond the mean field approximation by including fluctuations and also wave function saturation effects, and the evolution with both a fixed and a running coupling is investigated. We also study the nonpertur

Yeneng Sun, Yongchao Zhang

Many economic models include random shocks imposed on a large number (continuum) of economic agents with individual risk. In this context, an exact law of large numbers and its converse is presented in Sun (2006) to characterize the cancelation of individual risk via aggregation. However, it is well known that the Lebesgue unit interval is not suitable for m

Michael Assaf, Alex Kamenev, Baruch Meerson

We investigate how a catastrophic event (modeled as a temporary fall of the reproduction rate) increases the extinction probability of an isolated self-regulated stochastic population. Using a variant of the Verhulst logistic model as an example, we combine the probability generating function technique with an eikonal approximation to evaluate the exponentia

Tomohiro Yamada

Some new results concerning the equation $\sigma(N)=aM, \sigma(M)=bN$ are proved. As a corollary, there are only finitely many odd superperfect numbers with a fixed number of distinct prime factors.

Roberto Di Criscienzo, Luciano Vanzo

The instability against emission of fermionic particles by the trapping horizon of an evolving black hole is analyzed using the Hamilton-Jacobi tunneling method. This method automatically selects one special expression for the surface gravity of a changing horizon. The results also apply to point masses embedded in an expanding universe. As a bonus of the tu

B. D. Gerardot, D. Brunner, P. A. Dalgarno, K. Karrai

We observe dressed states and quantum interference effects in a strongly driven three-level quantum dot ladder system. The effect of a strong coupling field on one dipole transition is measured by a weak probe field on the second dipole transition using differential reflection. When the coupling energy is much larger than both the homoge-neous and inhomogene

D. J. Singh, M. H. Du

Density functional studies of 26K superconducting LaFeAs(O,F) are reported. We find a low carrier density, high density of states, $N(E_F)$ and modest phonon frequencies relative to $T_c$. The high $N(E_F)$ leads to proximity to itinerant magnetism, with competing ferromagnetic and antiferromagnetic fluctuations and the balance between these controlled by do

Sander Wahls, Holger Boche, Volker Pohl

We consider zero-forcing equalization of frequency selective MIMO channels by causal and linear time-invariant precoders in the presence of intersymbol interference. Our motivation is twofold. First, we are concerned with the optimal performance of causal precoders from a worst case point of view. Therefore we construct an optimal causal precoder, whereas co

Letizia Brunetti, Anna Maria Pastore

We present a compared analysis of some properties of indefinite almost $\mathcal{S}$-manifolds and indefinite $\mathcal{S}$-manifolds. We give some characterizations in terms of the Levi-Civita connection and of the characteristic vector fields. We study the sectional and $ϕ$-sectional curvature of indefinite almost $\mathcal{S}$-manifolds and state an expre

Sandhya Choubey, Viviana Niro, Werner Rodejohann

Among all neutrino mixing parameters, the atmospheric neutrino mixing angle theta_{23} introduces the strongest variation on the flux ratios of ultra high energy neutrinos. We investigate the potential of these flux ratio measurements at neutrino telescopes to constrain theta_{23}. We consider astrophysical neutrinos originating from pion, muon-damped and ne

I. F. Rúa, E. F. Combarro

A finite semifield is a finite nonassociative ring with identity such that the set of its nonzero elements is closed under the product. From any finite semifield a projective plane can be constructed. In this paper we obtain new semifield planes of orders 81 by means of computational methods. These computer-assisted results yield to a complete classification

Isabel Sainz, Gunnar Bjork

Dissipation may cause two initially entangled qubits to evolve into a separable state in a finite time. This behavior is called entanglement sudden death (ESD). We study to what extent quantum error correction can combat ESD. We find that in some cases quantum error correction can delay entanglement sudden death but in other cases quantum error correction ma

Miloslav Znojil

Quantum systems with real energies generated by an apparently non-Hermitian Hamiltonian may re-acquire the consistent probabilistic interpretation via an ad hoc metric which specifies the set of observables in the updated Hilbert space of states. The recipe is extended here to quantum toboggans. In the first step the tobogganic integration path is rectified

Luke A. Prendergast

In this paper we introduce an influence measure based on second order expansion of the RV and GCD measures for the comparison between unperturbed and perturbed eigenvectors of a symmetric matrix estimator. Example estimators are considered to highlight how this measure compliments recent influence analysis. Importantly, we also show how a sample based versio

Eric Fusy, Dominique Poulalhon, Gilles Schaeffer

A bijection $Φ$ is presented between plane bipolar orientations with prescribed numbers of vertices and faces, and non-intersecting triples of upright lattice paths with prescribed extremities. This yields a combinatorial proof of the following formula due to R. Baxter for the number $Θ_{ij}$ of plane bipolar orientations with $i$ non-polar vertices and $j$

Domenico Fiorenza, Marco Manetti, Elena Martinengo

We identify Cech cocycles in nonabelian (formal) group cohomology with Maurer-Cartan elements in a suitable L-infinity algebra. Applications to deformation theory are described.

Jian Li, K. Chalapat, G. S. Paraoanu

We study analytically and numerically the problem of two qubits with fixed coupling irradiated with quantum or classical fields. In the classical case, we derive an effective Hamiltonian, and construct composite pulse sequences leading to a CNOT gate. In the quantum case, we show that qubit-qubit-photon multiparticle entanglement and maximally entangled two-

Anne-Laure Dalibard

The goal of this paper is to describe in mathematical terms the effect on the ocean circulation of a random stationary wind stress at the surface of the ocean. In order to avoid singular behaviour, non-resonance hypotheses are introduced, which ensure that the time frequencies of the wind-stress are different from that of the Earth rotation. We prove a conve

Z. Osmanov

For studying how the field lines are twisting nearby the light cylinder surface, which provides the free motion of AGN winds through the mentioned area, the investigation of the centrifugally driven curvature drift instability is presented. Studying the dynamics of the relativistic MHD flow close to the light cylinder surface, by applying a single particle a

Sofia Olhede, Adam Sykulski, Grigorios Pavliotis

This paper proposes a novel multiscale estimator for the integrated volatility of an Ito process, in the presence of market microstructure noise (observation error). The multiscale structure of the observed process is represented frequency-by-frequency and the concept of the multiscale ratio is introduced to quantify the bias in the realized integrated volat

Frederic Bourgeois, Otto van Koert

We show that on any closed contact manifold of dimension greater than 1 a contact structure with vanishing contact homology can be constructed. The basic idea for the construction comes from Giroux. We use a special open book decomposition for spheres. The page is the cotangent bundle of a sphere and the monodromy is given by a left-handed Dehn twist. In the

Donato Bini, Christian Cherubini, Carmen Chicone, Bahram Mashhoon

We study the linear post-Newtonian approximation to general relativity known as gravitoelectromagnetism (GEM); in particular, we examine the similarities and differences between GEM and electrodynamics. Notwithstanding some significant differences between them, we find that a special nonstationary metric in GEM can be employed to show {\it explicitly} that i

Mehdi Nadjafikhah, Seyed-Reza Hejazi

Symmetries of a differential equations is one of the most important concepts in theory of differential equations and physics. One of the most prominent equations is KdV (Kortwege-de Vries) equation with application in shallow water theory. In this paper we are going to explain a particular method for finding symmetries of KdV equation, which is called Harris

Anna Fino, Luigi Vezzoni

We obtain a generalization of the Kodaira-Morrow stability theorem for cosymplectic structures. We investigate cosymplectic geometry on Lie groups and on their compact quotients by uniform discrete subgroups. In this way we show that a compact solvmanifold admits a cosymplectic structure if and only if it is a finite quotient of a torus.

Romesh K. Kaul

The Principle of Naturalness of small parameters of a theory is reviewed. While quantum field theories constructed from gauge fields and fermions only are natural, those containing elementary scalar fields are not. In particular the Higgs boson mass in the Standard Model of electro-weak forces is not stable against radiative corrections. Two old canonical so

Nobuhito Maru

We show that the gluon fusion amplitude in the gauge-Higgs unification scenario is finite in any dimension regardless of its nonrenormalizability. This result is supported by the fact that the local operator describing the gluon fusion process is forbidden by the higher dimensional gauge invariance. We explicitly calculate the gluon fusion amplitude in an ar

J. A. Bergstra, C. A. Middelburg

Threads as considered in basic thread algebra are primarily looked upon as behaviours exhibited by sequential programs on execution. It is a fact of life that sequential programs are often fragmented. Consequently, fragmented program behaviours are frequently found. In this paper, we consider this phenomenon. We extend basic thread algebra with the barest me

V. L. Mironov, S. V. Mironov

In this paper we represent the generalization of relativistic quantum mechanics on the base of eght-component values "octons", generating associative noncommutative spatial algebra. It is shown that the octonic second-order equation for the eight-component octonic wave function, obtained from the Einshtein relation for energy and momentum, describes

J. T. Lu, Jian-Sheng Wang

Based on generalized quantum Langevin equations for the tight-binding wave function amplitudes and lattice displacements, electron and phonon quantum transport are obtained exactly using molecular dynamics (MD) in the ballistic regime. The electron-phonon interactions can be handled with a quasi-classical approximation. Both charge and energy transport and t

A. A. Vasiliev, A. E. Miroshnichenko, M. Ruzzene

We construct a two-field higher-order gradient micropolar model for Cosserat media on the basis of a square lattice of elements with rotational degrees of freedom. This model includes equations of single-field higher-order gradient micropolar theory, and additional ones, which allow modelling of short wavelength phenomena. We demonstrate an example of short

Reginald D. Smith

A common feature of mycorrhizal observation is the growth of the infection on the plant root as a percent of the infected root or root tip length. Often, this is measured as a logistic curve with an eventual, though usually transient, plateau. It is shown in this paper that the periods of stable percent infection in the mycorrhizal growth cycle correspond to

Philippe Di Francesco, Rinat Kedem

We define the cluster algebra associated with the Q-system for the Kirillov-Reshetikhin characters of the quantum affine algebra $U_q(\hat{\g})$ for any simple Lie algebra g, generalizing the simply-laced case treated in [Kedem 2007]. We describe some special properties of this cluster algebra, and explain its relation to the deformed Q-systems which appeare

Aleksandar Donev, Berni J. Alder, Alejandro L. Garcia

A novel stochastic fluid model is proposed with non-ideal structure factor consistent with compressibility, and adjustable transport coefficients. This Stochastic Hard Sphere Dynamics (SHSD) algorithm is a modification of the Direct Simulation Monte Carlo (DSMC) algorithm and has several computational advantages over event-driven hard-sphere molecular dynami

Masahiro Hotta

We propose a protocol for quantum energy teleportation which transports energy in spin chains to distant sites only by local operations and classical communication. By utilizing ground-state entanglement and notion of negative energy density region, energy is teleported without breaking any physical laws including causality and local energy conservation. Bec

Steve Croft, Wil van Breugel, Michael J. I. Brown, Wim de Vries

We used the Near Infrared Camera on Keck I to obtain Ks-band images of four candidate high-redshift radio galaxies selected using optical and radio data in the NOAO Deep Wide-Field Survey in Bootes. Our targets have 1.4 GHz radio flux densities greater than 1 mJy, but are undetected in the optical to fainter than 24 Vega mag. Spectral energy distribution fit

Marta Lewicka, Stefan Müller

We study the Korn-Poincaré inequality: \|u\|_{W^{1,2}(S^h)} < C_h \|D(u)\|_{L^2(S^h)}, in domains S^h that are shells of small thickness of order h, around an arbitrary smooth and closed hypersurface S in R^n. By D(u) we denote the symmetric part of the gradient \nabla u, and we assume the tangential boundary conditions: u\vec n^h = 0 on \partial S^h. We pro

T. Adams, P. Batra, L. Bugel, L. Camilleri

This article presents the physics case for a new high-energy, ultra-high statistics neutrino scattering experiment, NuSOnG (Neutrino Scattering on Glass). This experiment uses a Tevatron-based neutrino beam to obtain over an order of magnitude higher statistics than presently available for the purely weak processes $ν_μ+e^- \to ν_μ+ e^-$ and $ν_μ+ e^- \to ν_

Namig J. Guliyev

Inverse problems of recovering the coefficients of Sturm-Liouville problems with the eigenvalue parameter linearly contained in one of the boundary conditions are studied: (1) from the sequences of eigenvalues and norming constants; (2) from two spectra. Necessary and sufficient conditions for the solvability of these inverse problems are obtained.

D. A. Braje, M. S. Kirchner, S. Osterman, T. Fortier

Broadband femtosecond-laser frequency combs are filtered to spectrographically resolvable frequency-mode spacing, and the limitations of using cavities for spectral filtering are considered. Data and theory are used to show implications to spectrographic calibration of high-resolution, astronomical spectrometers.

M. Kiguchi, O. Tal, S. Wohlthat, F. Pauly

Highly conductive molecular junctions were formed by direct binding of benzene molecules between two Pt electrodes. Measurements of conductance, isotopic shift in inelastic spectroscopy and shot noise compared with calculations provide indications for a stable molecular junction where the benzene molecule is preserved intact and bonded to the Pt leads via ca

Yue-Kin Tsang, William R. Young

We develop a new nonlinear stability method, the Energy-Enstrophy (EZ) method, that is specialized to two-dimensional hydrodynamics; the method is applied to a beta-plane flow driven by a sinusoidal body force, and retarded by drag with damping time-scale mu^{-1}. The standard energy method (Fukuta and Murakami, J. Phys. Soc. Japan, 64, 1995, pp 3725) shows

Joseph Polchinski

The evolution of cosmic string networks is an interesting dynamical problem. The equations governing these networks are classical and fully specified, but the length scale at which cosmic string loops form has been uncertain to tens of orders of magnitude. Numerical simulations are limited in the range of length and time scales they can reach, while analytic

James Q. Feng, C. F. Gallo

The measured rotation velocity profiles of mature spiral galaxies are successfully described with a gravitational model consisting of a thin axisymmetric disk of finte radius. The disk is assumed uniformly thin but with variable radial mass density. The governing integral equation is based on mechanical balance between Newtonian gravitational and centrifugal

Krzysztof T. Chyzy, Ronald J. Buta

We report the discovery of a coherent magnetic spiral structure within the nearby ringed Sab galaxy NGC 4736. High sensitivity radio polarimetric data obtained with the VLA at 8.46GHz and 4.86GHz show a distinct ring of total radio emission precisely corresponding to the bright inner pseudoring visible in other wavelengths. However, unlike the total radio em

Ping Nang Ma, Kai Yu Yang, Lode Pollet, J. V. Porto

The coexistence of superfluid and Mott insulator, due to the quadratic confinement potential in current optical lattice experiments, makes the accurate detection of the superfluid-Mott transition difficult. Studying alternative trapping potentials which are experimentally realizable and have a flatter center, we find that the transition can be better resolve

Michael Marks, Pavel Kroupa, Holger Baumgardt

Recently de Marchi, Paresce & Pulone (2007) studied a sample of twenty globular clusters and found that all clusters with high concentrations have steep stellar mass-functions while clusters with low concentration have comparatively shallow mass-functions. No globular clusters were found with a flat mass-function and high concentration. This seems curious si

D. W. Utami, A. A. Clerk

We study entanglement dynamics in a system consisting of a qubit dispersively coupled to a finite-temperature, dissipative, driven oscillator. We show that there are two generic ways to generate entanglement: one can entangle the qubit either with the phase or the amplitude of the oscillator&#39;s motion. Using an exact solution of the relevant quantum maste

Claudio Ugalde, Richard Azuma, Aaron Couture, Joachim Görres

The $^{19}$F($α$,p)$^{22}$Ne reaction is considered to be one of the main sources of fluorine depletion in AGB and Wolf-Rayet stars. The reaction rate still retains large uncertainties due to the lack of experimental studies available. In this work the yields for both exit channels to the ground state and first excited state of $^{22}$Ne have been measured a