January 2005 arXiv papers — page 8

Florian Girelli, Etera R. Livine

Loop Quantum Gravity defines the quantum states of space geometry as spin networks and describes their evolution in time. We reformulate spin networks in terms of harmonic oscillators and show how the holographic degrees of freedom of the theory are described as matrix models. This allow us to make a link with non-commutative geometry and to look at the issu

Matthew T. Glossop, Kevin Ingersent

We extend the numerical renormalization-group method to Bose-Fermi Kondo models (BFKMs), describing a local moment coupled to a conduction band and a dissipative bosonic bath. We apply the method to the Ising-symmetry BFKM with a bosonic bath spectral function $η(ω)\propto ω^s$, of interest in connection with heavy-fermion criticality. For $0<s<1$, an intera

D. Khmelev, M. Yampolsky

It is shown that if $f$ and $g$ are any two analytic critical circle mappings with the same irrational rotation number, then the conjugacy that maps the critical point of $f$ to that of $g$ has regularity $C^{1+α}$ at the critical point, with a universal value of $α>0$. As a consequence, a new proof of the hyperbolicity of the full renormalization horseshoe

W. Lohmann

The electromagnetic and weak dipole moments of the Tau-lepton have been measured by experiments at e+e- colliders. Data samples of e+e- --> tau+tau-, e+e- --> tau+tau- gamma and e+e- --> e+e-tau+tau- events collected at centre-of-mass energies between 10 and 200 GeV are used. No deviation from the Standard Model is found. Limits on the moments are summarised

Dongsu Bak, Seok Kim, Kimyeong Lee

We consider supermembranes in the maximally supersymmetric plane wave geometry of the eleven dimensions and construct complete solutions of the continuum version of the 1/4 BPS equations. The supermembranes may have an arbitrary number of holes and arbitrary cross sectional shapes. In the matrix regularized version, we solve the matrix equations for several

M. Bauer, S. Coulomb, S. N. Dorogovtsev

We consider the ferromagnetic Ising model on a highly inhomogeneous network created by a growth process. We find that the phase transition in this system is characterised by the Berezinskii--Kosterlitz--Thouless singularity, although critical fluctuations are absent, and the mean-field description is exact. Below this infinite order transition, the magnetiza

Yang Gao, Chong Sheng Li, Jian Jun Liu

We present a universal formalism for transverse momentum resummation in the view of soft-collinear effective theory (SCET), and establish the relation between our SCET formula and the well known Collins-Soper-Sterman&#39;s pQCD formula at the next-to-leading logarithmic order (NLLO). We also briefly discuss the reformulation of joint resummation in SCET.

Shinya Kanemura, Koichi Matsuda, Toshihiko Ota, Tetsuo Shindou

We study phenomenological predictions in the scenario with the quasi-degenerate relation among neutrino Dirac masses, m_D1 simeq m_D2 < m_D3, assuming the bi-maximal mixing at the grand unification scale in supersymmetric standard models with right-handed neutrinos. A sufficient lepton number asymmetry can be produced for successful leptogenesis. The lepton

Jean-Guillaume Dumas, Clément Pernet, Zhendong Wan

This article deals with the computation of the characteristic polynomial of dense matrices over small finite fields and over the integers. We first present two algorithms for the finite fields: one is based on Krylov iterates and Gaussian elimination. We compare it to an improvement of the second algorithm of Keller-Gehrig. Then we show that a generalization

E. Habart, A. Abergel, C. M. Walmsley, D. Teyssier

We present high angular resolution images of the H$_2$ 1-0 S(1) line emission obtained with the Son of ISAAC (SOFI) at the New Technology Telescope (NTT) of the Horsehead nebula. These observations are analysed in combination with H$α$ line emission, aromatic dust, CO and dust continuum emissions. The Horsehead nebula illuminated by the O9.5V star $σ$ Ori ($

Victor J. W. Guo, Jiang Zeng

Let $$ S_{m,n}(q):=\sum_{k=1}^{n}\frac{1-q^{2k}}{1-q^2} (\frac{1-q^k}{1-q})^{m-1}q^{\frac{m+1}{2}(n-k)}. $$ Generalizing the formulas of Warnaar and Schlosser, we prove that there exist polynomials $P_{m,k}(q)\in\mathbb{Z}[q]$ such that $$ S_{2m+1,n}(q) =\sum_{k=0}^{m}(-1)^kP_{m,k}(q) \frac{(1-q^n)^{m+1-k}(1-q^{n+1})^{m+1-k}q^{kn}} {(1-q^2)(1-q)^{2m-3k}\prod

P. Palaniyandi, P. Muruganandam, M. Lakshmanan

We analyze the size limits of coupled map lattices with diffusive coupling at the crossover of low-dimensional to high-dimensional chaos. We investigate the existence of standing-wave-type periodic patterns, within the low-dimensional limit, in addition to the stable synchronous chaotic states depending upon the initial conditions. Further, we bring out a co

Alan D. Rendall

It is shown that spatially homogeneous solutions of the Einstein equations coupled to a nonlinear scalar field and other matter exhibit accelerated expansion at late times for a wide variety of potentials $V$. These potentials are strictly positive but tend to zero at infinity. They satisfy restrictions on $V&#39;/V$ and $V&#39;&#39;/V&#39;$ related to the s

Michael Ching

We describe a cooperad structure on the simplicial bar construction on a reduced operad of based spaces or spectra and, dually, an operad structure on the cobar construction on a cooperad. We also show that if the homology of the original operad (respectively, cooperad) is Koszul, then the homology of the bar (respectively, cobar) construction is the Koszul

Takuya Mouri, Hayato Nakano, Hideaki Takayanagi

We study theoretically how decoherence affects superposition states composed of entangled states in inductively coupled two superconducting flux-qubits. We discover that the quantum fluctuation of an observable in a coupled flux-qubit system plays a crucial role in decoherence when the expectation value of the observable is zero. This examplifies that decohe

Stanislav Boldyrev, Arieh Konigl

It was recently suggested by Boldyrev & Gwinn that the characteristics of radio scintillations from distant pulsars are best understood if the interstellar electron-density fluctuations that cause the time broadening of the radio pulses obey non-Gaussian statistics. In this picture the density fluctuations are inferred to be strong on very small scales ($\si

N. N. Ajitanand, J. M. Alexander, P. Chung, W. G. Holzmann

Methodology is presented for analysis of two-particle azimuthal angle correlation functions obtained in collisions at ultra-relativistic energies. We show that harmonic and di-jet contributions to these correlation functions can be reliably decomposed by two techniques to give an accurate measurement of the jet-pair distribution. Results from detailed Monte

Kamiokande Collaboration

We present a combined analysis of fully-contained, partially-contained and upward-going muon atmospheric neutrino data from a 1489 day exposure of the Super--Kamiokande detector. The data samples span roughly five decades in neutrino energy, from 100 MeV to 10 TeV. A detailed Monte Carlo comparison is described and presented. The data is fit to the Monte Car

Cenke Xu, J. E. Moore

The phase diagram of the uniaxially anisotropic $s=1$ antiferromagnet on the kagomé lattice includes a critical line exactly described by the classical three-color model. This line is distinct from the standard geometric classical criticality that appears in the classical limit ($s \to \infty$) of the 2D XY model; the $s=1$ geometric T=0 critical line separa

J. K. Vizzotto, T. Altenkirch, A. Sabry

We show that the model of quantum computation based on density matrices and superoperators can be decomposed in a pure classical (functional) part and an effectful part modeling probabilities and measurement. The effectful part can be modeled using a generalization of monads called arrows. We express the resulting executable model of quantum computing in the

Pablo Arrighi, Gilles Dowek

With a view towards models of quantum computation and/or the interpretation of linear logic, we define a functional language where all functions are linear operators by construction. A small step operational semantic (and hence an interpreter/simulator) is provided for this language in the form of a term rewrite system. The linear-algebraic lambda-calculus h

Stefan Scheel, Per-Kristian Rekdal, Peter L. Knight, Edward A. Hinds

We derive scaling laws for the spin decoherence of neutral atoms trapped near conducting and superconducting plane surfaces. A new result for thin films sheds light on the measurement of Y.J. Lin, I. Teper, C. Chin, and V. Vuletić [Phys. Rev. Lett. \textbf{92}, 050404 (2004)]. Our calculation is based on a quantum-theoretical treatment of electromagnetic rad

Wang Guowen

A particle is described as a non-spreading wave packet satisfying a linear equation within the framework of special relativity. Young&#39;s and other interference experiments are explained with a hypothesis that there is a coupling interaction between the peaked and non-peaked pieces of the wave packet. This explanation of the interference experiments provid

Péter Lévay, Szilvia Nagy, János Pipek

An elementary formula for the von Neumann and Renyi entropies describing quantum correlations in two-fermionic systems having four single particle states is presented. An interesting geometric structure of fermionic entanglement is revealed. A connection with the generalized Pauli principle is established.

Magnus T. L. Hsu, Warwick P. Bowen, Nicolas Treps, Ping Koy Lam

A light beam is said to be position squeezed if its position can be determined to an accuracy beyond the standard quantum limit. We identify the position and momentum observables for bright optical beams and show that position and momentum entanglement can be generated by interfering two position, or momentum, squeezed beams on a beam splitter. The position

Kenneth Brown, Aram Harrow, Isaac Chuang

Systematic errors in quantum operations can be the dominating source of imperfection in achieving control over quantum systems. This problem, which has been well studied in nuclear magnetic resonance, can be addressed by replacing single operations with composite sequences of pulsed operations, which cause errors to cancel by symmetry. Remarkably, this can b

Sohang C. Gandhi, Costas J. Efthimiou

The double-cone ascending an inclined V-rail is a common exhibit used for demonstrating concepts related to center-of-mass in introductory physics courses. While the conceptual explanation is well-known--the widening of the ramp allows the center of mass of the cone to drop, overbalancing the increase in altitude due to the inclination of the ramp--there rem

Ken Sekimoto

By a modular combination of mesoscopic detectors and gates, we present a thoughtful pump that transports gas particles against the difference of their density at the expense of the diffusion of another species of gas particles. We also discuss briefly the relevance of the model to the study of structure-function relationship of the biomolecular machines.

Volodymyr Krasnoholovets

The geometry of the elementary charge is studied in the framework of the concept of space considered as a tessellation lattice (&#39;tessellattice&#39;), which has recently been developed by M. Bounias and the author. The descriptive-geometric sense of the electric and magnetic fields and their carriers - photons - is analyzed. The notion of the scalar and v

Wang Guowen

A geometric illustration of the Lorentz transformations is given. According to similarity between space and time and correspondence between a ruler and a clock, like the division number in a moving ruler, the tick number of a moving clock is independent of its relative speed and hence invariant under the Lorentz transformations. So the hand of the moving clo

P. Agnoli, G. D&#39;Agostini

The French Academy units of time and length - the second and the meter - are traditionally considered independent from each other. However, it is a matter of fact that a meter simple pendulum beats virtually the second in each oscillation, a `surprising&#39; coincidence that has no physical reason. We shortly review the steps that led to the choice of the me

L. Zamick, A. Escuderos, A. Mekjian

In the single j-shell, the configuration of an even-even Ti isotope consists of 2 protons and n neutrons. The I=0 wave function can be written in terms of D(J,Jv)&#39;s, which are the probability amplitudes for the 2 protons to couple to J and the n neutrons to couple to Jv (where J stands for the angular momentum and v for the seniority quantum number). The

A. Escuderos, L. Zamick

We have found an alternate way of deriving the Ginocchio-Haxton relation [(2j-3)/6], where the square brackets mean the largest integer that is less than or equal to what is inside them. Our derivation involves the calculation of the number of states with total angular momentum J=j for 3 identical particles (e.g., neutrons) in a j-shell.

V. R. Pandharipande, D. R. Phillips, U. van Kolck

We consider the relationship between P-wave pi-N scattering and the strength of the P-wave two-pion-exchange three-nucleon interaction (TPE3NI). We explain why effective theories that do not contain the delta resonance as an explicit degree of freedom tend to overestimate the strength of the TPE3NI. The overestimation can be remedied by higher-order terms in

A. Kievsky, E. Pace, G. Salme`

An approach for the description of the final state interaction in the evaluation of inclusive electromagnetic responses of a polarized Helium-3 target, is briefly illustrated. Preliminary results of calculations, where the final state interaction is fully taken into account for the two-body break-up channel, are compared with experimental data, showing a ver

E. Oset, D. Cabrera, V. K. Magas, L. Roca

In this talk I report on selected topics of hadron modification in the nuclear medium using the chiral unitary approach to describe the dynamics of the problems. I shall mention how antikaons, $η$, and $ϕ$ are modified in the medium and will report upon different experiments done or planned to measure the $ϕ$ width in the medium.

E. M. Tursunov, D. Baye, P. Descouvemont

Three variational approaches, the hyperspherical-harmonics, Gaussian-basis and Lagrange-mesh methods involving different coordinate systems, are compared in studies of $0^+$ bound-state energies in 3$α$ models. Calculations are performed with different versions of the shallow Ali-Bodmer potential (with and without Coulomb) and with the deep Buck-Friedrich-Wh

E. M. Tursunov

The energy spectrum of the $^{12}C$ nucleus with $(J^π, T)=(0^+,0)$ and $(2^+,0)$ is investigated in the framework of the multicluster dynamical model by using a deep $αα$-potential with forbidden states in the S and D waves. A very high sensitivity of the compact ground and first excited $2^+_1$ states energy levels to the description of the two-body forbid

V K Chandrasekar, M Senthilvelan, M Lakshmanan

We discuss a method of solving $n^{th}$ order scalar ordinary differential equations by extending the ideas based on the Prelle-Singer (PS) procedure for second order ordinary differential equations. We also introduce a novel way of generating additional integrals of motion from a single integral. We illustrate the theory for both second and third order equa

A. I. Nikishov, V. I. Ritus

The asymptotic representations of the functions ${\rm Ai}_1(x), {\rm Gi}(x), {\rm Ai}&#39;(x), {\rm Ai}^2(x), {\rm Bi}^ 2(x)$ are obtained. As a by-product, the factorial identity (21&#39;) is found. The derivation of asymptotic representations of the integral $\int_v^{\infty}dx{\rm Ai}(x)h(x,v)$ for $v\to-\infty$ and integrals, differing from it by the chan

Yeontaek Choi, Yuri V. Lvov, Sergey Nazarenko

In this paper we review recent developments in the statistical theory of weakly nonlinear dispersive waves, the subject known as Wave Turbulence (WT). We revise WT theory using a generalisation of the random phase approximation (RPA). This generalisation takes into account that not only the phases but also the amplitudes of the wave Fourier modes are random

Nikolai Nadirashvili, Yu Yuan

We classify homogeneous degree $d\neq2$ solutions to fully nonlinear elliptic equations.

Friedrich Wehrung

Let $(G,u)$ be an archimedean norm-complete dimension group with order unit. Continuing a previous paper, we study intervals (i.e., nonempty upward directed lower subsets) of $G$ which are closed with respect to the canonical norm of $(G,u)$. In particular, we establish a canonical one-to-one correspondence between closed intervals of $G$ and certain affine

Miroslav Ploscica, Jiri Tuma, Friedrich Wehrung

We prove that for any free lattice F with at least $\aleph\_2$ generators in any non-distributive variety of lattices, there exists no sectionally complemented lattice L with congruence lattice isomorphic to the one of F. This solves a question formulated by Grätzer and Schmidt in 1962. This yields in turn further examples of simply constructed distributive

Friedrich Wehrung

The Congruence Lattice Problem asks whether every algebraic distributive lattice is isomorphic to the congruence lattice of a lattice. It was hoped that a positive solution would follow from E. T. Schmidt&#39;s construction or from the approach of P. Pudlak, M. Tischendorf, and J. Tuma. In a previous paper, we constructed a distributive algebraic lattice $A$

Mikhail Zaidenberg

This is a renovated list of open problems, to appear in: &#34;Affine Algebraic Geometry&#34; conference Proceedings volume in Contemporary Mathematics series of the Amer. Math. Soc. Ed. by Jaime Gutierrez, Vladimir Shpilrain, and Jie-Tai Yu.

Yu Yuan

We show that any global solution to the special Lagrangian equations with the phase larger than a critical value must be quadratic.

Andrea Bruno, Alessandro Verra

The authors prove that $\Cal M_{15}$ is rationally connected

Francisco Urbano

We show that the Clifford torus and the totally geodesic real projective plane RP^2 in the complex projective plane CP^2 are the unique Hamiltonian stable minimal Lagrangian compact surfaces of CP^2 with genus less than or equal to 4, when the surface is orientable, and with Euler characteristic greater than or equal to -1, when the surface is nonorientable.

Detlef Mueller

This is a the first in a series of two articles devoted to the question of local solvability of doubly characteristic second order differential operators. For a large class of such operators, we show that local solvability at a given point implies &#34;essential dissipativity&#34; of the operator at this point. By means of Hoermander&#39;s classical necessar

Eugene Lytvynov

In [Yu.M. Berezansky, E. Lytvynov, D. A. Mierzejewski, Ukrainian Math. J. 55 (2003), 853--858 ], the Jacobi field of a Lévy process was derived. This field consists of commuting self-adjoint operators acting in an extended (interacting) Fock space. However, these operators have a quite complicated structure. In this note, using ideas from [L. Accardi. U. Fra

Jane Gilman, Linda Keen

Determining the space of free discrete two generator groups of Möbius transformations is an old and difficult problem. In this paper we show how to construct large balls of full dimension in this space. To do this, we begin with a marked discrete group of non-separating disjoint circle type. Such a group determines three disjoint or tangent planes. We prove

Jesús A. De Loera, Tyrrell B. McAllister

We investigate the problem of computing tensor product multiplicities for complex semisimple Lie algebras. Even though computing these numbers is #P-hard in general, we show that if the rank of the Lie algebra is assumed fixed, then there is a polynomial time algorithm, based on counting the lattice points in polytopes. In fact, for Lie algebras of type A_r,

James Nolen, Jack Xin

Speed ensemble of bistable (combustion) fronts in mean zero stationary Gaussian shear flows inside two and three dimensional channels is studied with a min-max variational principle. In the small root mean square regime of shear flows, a new class of multi-scale test functions are found to yield speed asymptotics. The quadratic speed enhancement law holds wi

P. Bantay

We discuss some properties of the tower of mapping class group representations associated to a Rational Conformal Field Theory. In particular, after reviewing the elementary properties of the modular representation, we discuss the Galois action, the structure of the projective kernel, and the trace identities generalizing the formula of Verlinde.

R. J. Flores, J. Scherer

One way to understand the mod p homotopy theory of classifying spaces of finite groups is to compute their BZ/p-cellularization. In the easiest cases this is a classifying space of a finite group (always a finite p-group). If not, we show that it has infinitely many non-trivial homotopy groups. Moreover they are either p-torsion free or else infinitely many

Sara Brofferio, Wolfgang Woess

We determine all positive harmonic functions for a large class of &#34;semi-isotropic&#34; random walks on the lamplighter group, i.e., the wreath product of the cyclic group of order q with the infinite cyclic group. This is possible via the geometric realization of a Cayley graph of that group as the Diestel-Leader graph DL(q,q). More generally, DL(q,r) is

Pierre Andreoletti

We consider Sinai&#39;s random walk in random environment. We prove that infinitely often (i.o.) the size of the concentration neighborhood of this random walk is almost surely bounded. As an application we get that i.o. the maximal distance between two favorite sites is almost surely bounded.

George Grätzer, Friedrich Wehrung

We prove that every lattice with more than one element has a proper congruence-preserving extension.

Friedrich Wehrung

We introduce the dimension monoid of a lattice L, denoted by Dim L. The monoid Dim L is commutative and conical, the latter meaning that the sum of any two nonzero elements is nonzero. Furthermore, Dim L is given along with the dimension map, $\Dim$, from L x L to Dim L, which has the intuitive meaning of a distance function. The maximal semilattice quotient

George Grätzer, Friedrich Wehrung

Let A and B be lattices with zero. The classical tensor product, $A\otimes B$, of A and B as join-semilattices with zero is a join-semilattice with zero; it is, in general, not a lattice. We de&#64257;ne a very natural condition: $A \otimes B$ is capped (that is, every element is a &#64257;nite union of pure tensors) under which the tensor product is always

Aleksandar Ivić

Several results are obtained concerning multiplicities of zeros of the Riemann zeta-function $ζ(s)$. They include upper bounds for multiplicities, showing that zeros with large multiplicities have to lie to the left of the line $σ= 1$. A zero-density counting function involving multiplicities is also discussed.

Friedrich Wehrung

We extend the usual de&#64257;nition of coherence, for modules over rings, to partially ordered right modules over a large class of partially ordered rings, called po-rings. In this situation, coherence is equivalent to saying that solution sets of &#64257;nite systems of inequalities are &#64257;nitely generated semimodules. Coherence for ordered rings and

Jean-François Caillot, Friedrich Wehrung

We study notions such as &#64257;nite presentability and coherence, for partially ordered abelian groups and vector spaces. Typical results are the following: (i) A partially ordered abelian group G is &#64257;nitely presented if and only if G is &#64257;nitely generated as a group, the positive cone G^+ is well-founded as a partially ordered set, and the se

George Grätzer, Friedrich Wehrung

Let $A$, $B$, and $S$ be (v,0)-semilattices and let $f: A\to B$ be a (v,0)-embedding. Then the canonical map, $f \otimes \id\_S$, of the tensor product $A \otimes S$ into the tensor product $B \otimes S$ is not necessarily an embedding. The (v,0)-semilattice $S$ is flat, if for every embedding $f : A\to B$, the canonical map $f\otimes\id$ is an embedding. We

George Grätzer, Friedrich Wehrung

In 1968, E. T. Schmidt introduced the M\_3[D] construction, an extension of the &#64257;ve-element nondistributive lattice M\_3 by a bounded distributive lattice D, de&#64257;ned as the lattice of all triples $(x, y, z) \in D^3$ satisfying $x \mm y = x \mm z = y \mm z$. The lattice M\_3[D] is a modular congruence-preserving extension of D. In this paper, we

Kouichi Takemura

Several results on Heun&#39;s equation are generalized to a certain class of Fuchsian differential equations. Namely, we obtain integral representations of solutions and develop Hermite-Krichever Ansatz on them. In particular, we investigate linear differential equations that produce Painlevé equation by monodromy preserving deformation and obtain solutions

Bogdan Oporowski, David Zhao

We generalize the Five Color Theorem by showing that it extends to graphs with two crossings. Furthermore, we show that if a graph has three crossings, but does not contain K_6 as a subgraph, then it is also 5-colorable. We also consider the question of whether the result can be extended to graphs with more crossings.

Federico Ardila, Richard P. Stanley

A survey of tilings in the plane for a general audience.

Holger Brenner

We prove that the tight closure and the graded plus closure of a homogeneous ideal coincide for a two-dimensional N-graded domain of finite type over the algebraic closure of a finite field. This answers in this case a ``tantalizing question&#39;&#39; of Hochster.

Holger Brenner

We study computational aspects of the tight closure of a homogeneous primary ideal in a two-dimensional normal standard-graded domain. We show how to use slope criteria for the sheaf of syzygies for generators of the ideal to compute the tight closure. Our method gives in particular an algorithm to compute the tight closure of three elements under the condit

Holger Brenner

We characterize the tight closure of graded primary ideals in a homogeneous coordinate ring over an elliptic curve by numerical conditions and we show that it is in positive characteristic the same as the plus closure.

Ion I. Cotăescu

A method is proposed for generalizing the Euclidean Taub-NUT space, regarded as the appropriate background of the Dirac magnetic monopole, to non-Abelian Kaluza-Klein theories involving potentials of generalized monopoles. Usual geometrical methods combined with a recent theory of the induced representations governing the Taub-NUT isometries lead to a genera

Stephen C. Davis, Pierre Binetruy, Anne-Christine Davis

Axionic cosmic string solutions are investigated in a superstring motivated model with a pseudo-anomalous U(1) gauge symmetry. The inclusion of a gauge field and spatially varying dilaton allow local defect solutions with finite energy per unit length to be found. Fermion zero modes (whose presence is implied by supersymmetry) are also analysed. The correspo

Jose A. de Azcarraga

We discuss the rôle of enlarged superspaces in two seemingly different contexts, the structure of the $p$-brane actions and that of the Cremmer-Julia-Scherk eleven-dimensional supergravity. Both provide examples of a common principle: the existence of an {\it enlarged superspaces coordinates/fields correspondence} by which all the (worldvolume or spacetime)

Sachiko Oshima, Takeshi Nihei, Takehisa Fujita

The nucleon EDM is shown to be directly related to the EDM of atomic systems. From the observed EDM values of the atomic Hg system, the neutron EDM can be extracted, which gives a very stringent constraint on the supersymmetry parameters. It is also shown that the measurement of Nitrogen and Thallium atomic systems should provide important information on the

Gouranga C. Nayak, Jian-Wei Qiu, George Sterman

We explore the role of soft gluon exchange in heavy quarkonium production at large transverse momentum. We find uncanceled infrared poles at NNLO that are not matched by conventional NRQCD matrix elements. We show, however, that gauge invariance and factorization require that conventional NRQCD production operators be modified to include nonabelian phases or

Cristina Volpe

We propose to use charged-current neutrino-nucleus interactions as a probe of the many virtual transitions involved in neutrinoless double-beta decay. By performing neutrino and anti-neutrino interaction studies on the initial and final nucleus respectively, one can get information on the two branches involved in the double-beta decay process. The measuremen

Mark Hindmarsh, Owe Philipsen

Weakly Interacting Massive Particles (WIMPs) of mass m freeze out at a temperature T_f ~ m/25, i.e. in the range 400 MeV -- 40 GeV for a particle in the typical mass range 10 -- 1000 GeV. The WIMP relic density, which depends on the effective number of relativistic degrees of freedom at T_f, may be measured to better than 1% by Planck, warranting comparable

Raul Acosta, Ruben Flores-Mendieta

The derivation of the 1/N_c expansions for the baryon vector and axial-vector currents, in the SU(3) symmetry limit and including perturbative SU(3) breaking, is reviewed. Symmetry breaking effects in the hyperon semileptonic decay form factors are reanalyzed. Fits to experimental data yield corrections to the leading vector and axial-vector form factors con

Andrzej J. Buras, Anton Poschenrieder, Selma Uhlig

We point out that in the case of a heavy top quark T, present in the Littlest Higgs model (LH), and the t-T mixing parameter x_L > 0.90 the contribution to B^0_{d,s}-\bar B^0_{d,s} mixing from box diagrams with two T exchanges cannot be neglected. Although formally O(v^4/f^4) with v = 246 GeV and f > 1 TeV, this contribution increases linearly with x_T = m_T

Ting-Wai Chiu, Tung-Han Hsieh

We investigate the mass spectrum of the pentaquark baryon ($ udud \bar s $) in quenched lattice QCD with exact chiral symmetry. Using 3 different interpolating operators, we measure their $ 3 \times 3 $ correlation matrix and obtain the eigenvalues $ A^{\pm} (t) $ with $ \pm $ parity, for 100 gauge configurations generated with Wilson gauge action at $ β= 6.

M. F. M. Lutz, E. E. Kolomeitsev

We discuss the formation of s- and d-wave baryon resonances as predicted by the chiral SU(3) symmetry of QCD. Based on the leading order term of the chiral Lagrangian a rich spectrum of molecules is generated, owing to final-state interactions. The spectrum of s- and d-wave baryon states with zero and non-zero charm is remarkably consistent with the empirica

Prasanta Das, Santosh Kumar Rai, Sreerup Raychaudhuri

We make a fresh evaluation of contributions to (g-2) of the muon in the framework of a preonic model with coloured vectorlike leptons and heavy coloured Z bosons and discuss their implications in the light of the recent Brookhaven measurement. It is shown that the observed deviation can be explained within this framework with masses and couplings consistent

K. Okada

This report presents the preliminary result for the prompt photon production cross section in proton-proton collisions in the mid-rapidity region using the PHENIX detector. The NLO pQCD calculation is in good agreement with the data. The measurement was made with and without an isolation cut. The isolation cut significantly improves the signal purity without

Etera R. Livine

One of the most important issues in quantum gravity is to identify its semi-classical regime. First the issue is to define for we mean by a semi-classical theory of quantum gravity, then we would like to use it to extract physical predictions. Writing an effective theory on a flat background is a way to address this problem and I explain how the non-commutat

Brien C. Nolan, Raül Vera

The studies in general relativity of rotating finite objects in equilibrium have usually focused on the case when they are truly isolated, this is, the models to describe finite objects are embedded in an asymptotically flat exterior vacuum. Known results ensure the uniqueness of the vacuum exterior field by using the boundary data for the exterior field giv

Jacek Jezierski, Jerzy Kijowski

A new parameterization of unconstrained degrees of freedom for gravitational field, used in Classical and Quantum Gravity {\bf 11}, 1055-1068 (1994), has been generalized to one-parameter family of such parameterizations, depending on a real parameter $β\in [0,2]$. The description introduced in CQG 11, 1055 corresponds to the special choice $β=0$. The method

Dörte Hansen

A binary system composed of an oscillating and rotating coplanar dusty disk and a point mass is considered. The conservative dynamics is treated on the Newtonian level. The effects of gravitational radiation reaction and wave emission are studied to leading quadrupole order. The related waveforms are given. The dynamical evolution of the system is determined

P. P. Fiziev, T. L. Bojadjiev, D. A. Georgieva

We consider for the first time the solutions of Klein-Gordon equation in gravitational field of {\em a massive} point source in GR. We examine numerically the basic bounded quantum state and the next few states in the discrete spectrum for different values of the orbital momentum. A novel feature of the solutions under consideration is the essential dependen

M. Anderson, P. T. Chrusciel, E. Delay

We show that the recent work of Lee [23] implies existence of a large class of new singularity-free strictly static Lorentzian vacuum solutions of the Einstein equations with a negative cosmological constant. This holds in all space-time dimensions greater than or equal to four, and leads both to strictly static solutions and to black hole solutions. The con

Tom Schrijvers, Thom Fruehwirth

Constraint Handling Rules (CHR) is a committed-choice rule-based language that was originally intended for writing constraint solvers. In this paper we show that it is also possible to write the classic union-find algorithm and variants in CHR. The programs neither compromise in declarativeness nor efficiency. We study the time complexity of our programs: th

Dominique Dutoit, Thierry Poibeau

In this paper, we present a rich semantic network based on a differential analysis. We then detail implemented measures that take into account common and differential features between words. In a last section, we describe some industrial applications.

W. Drabent, M. Milkowska

We advocate a declarative approach to proving properties of logic programs. Total correctness can be separated into correctness, completeness and clean termination; the latter includes non-floundering. Only clean termination depends on the operational semantics, in particular on the selection rule. We show how to deal with correctness and completeness in a d

Jose Ghislain Quenum Samir Aknine

in this paper we describe a method which allows agents to dynamically select protocols and roles when they need to execute collaborative tasks

C. dela Cruz, F. Yen, B. Lorenz, Y. Q. Wang

Evidence for a strong spin-lattice coupling in multiferroic HoMnO_3 is derived from thermal expansion measurements along a- and c-axis. The magnetoelastic effect results in sizable anomalies of the thermal expansivities at the antiferromagnetic (T_N) and the spin rotation (T_{SR}) transition temperatures as well as in a negative c-axis expansivity below room

Boris Kastening, Dirk K. Morr, Dirk Manske, Karl Bennemann

We predict a novel type of Josephson effect to occur in triplet superconductor - ferromagnet - triplet superconductor Josephson junctions. We show that the Josephson current, I_J, exhibits a rich dependence on the relative orientation between the ferromagnetic moment and the d-vectors of the superconductors. This dependence can be used to build several types

J. S. Brown

Attention is drawn to recent observation of a fluid phase of hydrogen nucleii in transition metal hydrides. It is suggested that phonon exchange processes might be responsible for the phase transition since bound pair states, analogous to Cooper pairs, would possess the required mobility and might moreover render the phase transition energetically favourable

P. A. Khomyakov, G. Brocks, V. Karpan, M. Zwierzycki

Landauer&#39;s formula relates the conductance of a quantum wire or interface to transmission probabilities. Total transmission probabilities are frequently calculated using Green function techniques and an expression first derived by Caroli. Alternatively, partial transmission probabilities can be calculated from the scattering wave functions that are obtai

Fernando A. Oliveira, Rafael Morgado, Alex Hansen, J. M. Rubi

We present evidence of the existence of a superdiffusive regime in systems with correlated disorder for which localization is suppressed. An expression for anomalous electrical conductivity at low frequencies is found by using a generalized Langevin equation whose memory function accounts for the interactions between the carriers. New mechanisms inducing a s