March 2006 arXiv papers — page 34

Masahiro Takeoka, Masahide Sasaki, Norbert Lütkenhaus

We investigate the implementation of binary projective measurements with linear optics. This problem can be viewed as a single-shot discrimination of two orthogonal pure quantum states. We show that any two orthogonal states can be perfectly discriminated using only linear optics, photon counting, coherent ancillary states, and feedforward. The statement hol

K. Hagino, T. Takehi, N. Takigawa

We propose the no-recoil approximation, which is valid for heavy systems, for a double folding nucleus-nucleus potential. With this approximation, the non-local knock-on exchange contribution becomes a local form. We discuss the applicability of this approximation for the elastic scattering of $^6$Li + $^{40}$Ca system. We find that, for this system and heav

Shilun Chen, Aigen Li, Daming Wei

Dust in the host galaxies of gamma-ray bursts (GRBs) dims and reddens their afterglow spectra. Knowledge of the nature of this dust is crucial for correcting for extinction, providing clues to the nature of GRB progenitors, and probing the interstellar medium of high-redshift galaxies as well as the nature of cosmic dust when the universe was much younger an

Jonathan K. Adams

Significant research has been done in the area of Role Based Access Control [RBAC]. Within this research there has been a thread of work focusing on adding parameters to the role and permissions within RBAC. The primary benefit of parameter support in RBAC comes in the form of a significant increase in specificity in how permissions may be granted. This pape

A. Ishikawa

We report the first measurement of the forward-backward asymmetry and the ratios of Wilson coefficients $A_9/A_7$ and $A_{10}/A_7$ in $B \to K^* \ell^+ \ell^-$, where $\ell$ represents an electron or a muon. We observe a large integrated forward-backward asymmetry with a significance of 3.4$\sigma$. The results are obtained from a data sample containing 386

Jorge Melendez, Katie Dodds-Eden, Jose A. Robles, ;

Despite the observational effort carried out in the last few decades, no perfect solar twin has been found to date. An important milestone was achieved a decade ago by Porto de Mello & da Silva, who showed that 18 Sco is almost a solar twin. In the present work, we use extremely high resolution (R = 10^5) high S/N Keck HIRES spectra to carry out a differenti

Isao Kishimoto, Sanefumi Moriyama, Shunsuke Teraguchi

It has been suggested that matrix string theory and light-cone string field theory are closely related. In this paper, we investigate the relation between the twist field, which represents string interactions in matrix string theory, and the three-string interaction vertex in light-cone string field theory carefully. We find that the three-string interaction

H. Kroger, J. F. Laprise, G. Melkonyan, R. Zomorrodi

We discuss the questions: How to compare quantitatively classical chaos with quantum chaos? Which one is stronger? What are the underlying physical reasons?

T. Wilk, H. P. Specht, S. C. Webster, G. Rempe

Single-photons of well-defined polarisation that are deterministically generated in a single spatio-temporal field mode are the key to the creation of multi-partite entangled states in photonic networks. Here, we present a novel scheme to produce such photons from a single atom in an optical cavity, by means of vacuum-stimulated Raman transitions between the

Dianne P. O'Leary, Gavin K. Brennen, Stephen S. Bullock

Robust quantum computation with d-level quantum systems (qudits) poses two requirements: fast, parallel quantum gates and high fidelity two-qudit gates. We first describe how to implement parallel single qudit operations. It is by now well known that any single-qudit unitary can be decomposed into a sequence of Givens rotations on two-dimensional subspaces o

Martin Kiffner, Joerg Evers, Christoph H. Keitel

The fluorescence light emitted by a 4-level system in $J=1/2$ to $J=1/2$ configuration driven by a monochromatic laser field and in an external magnetic field is studied. We show that the spectrum of resonance fluorescence emitted on the $π$ transitions shows a signature of spontaneously generated interference effects. The degree of interference in the fluor

Joonwoo Bae, Antonio Acin

The impossibility of perfect cloning and state estimation are two fundamental results in Quantum Mechanics. It has been conjectured that quantum cloning becomes equivalent to state estimation in the asymptotic regime where the number of clones tends to infinity. We prove this conjecture using two known results of Quantum Information Theory: the monogamy of q

Qi Zhang, Biao Wu

We present a general theoretical framework for the exact treatment of a hybrid system that is composed of a quantum subsystem and a classical subsystem. When the quantum subsystem is dynamically fast and the classical subsystem is slow, a vector potential is generated with a simple canonical transformation. This vector potential, on one hand, gives rise to t

R. Fermani, S. Scheel, P. L. Knight

We present a first-principles derivation of spatial atomic-sublevel decoherence near dielectric and metallic surfaces. The theory is based on the electromagnetic-field quantization in absorbing dielectric media. We derive an expression for the time-variation of the off-diagonal matrix element of the atomic density matrix for arbitrarily shaped substrates. Fo

Andrei P. Kirilyuk

Following Max Planck's hypothesis of quanta (quant-ph/0012069) and the matter wave idea of Louis de Broglie (quant-ph/9911107), Erwin Schroedinger proposed, at the beginning of 1926, the concept of wavefunction and wave equation for it. Though endowed with a realistic undular interpretation by its father, the wavefunction could not be considered as a rea

G. Abramson, L. Giuggioli, V. M. Kenkre, J. W. Dragoo

We analyze data from a long term field project in New Mexico, consisting of repeated sessions of mark-recaptures of Peromyscus maniculatus (Rodentia: Muridae), the host and reservoir of Sin Nombre Virus (Bunyaviridae: Hantavirus). The displacements of the recaptured animals provide a means to study their movement from a statistical point of view. We extract

Gordon Chalmers

The Poincare conjecture is analyzed in the context of Calabi-Yau $n$-folds. A simple treatment is given by embedding the three-manifolds into these CY manifolds, and then taking the orbifold limit. The higher-dimensional proofs are also available in this context.

Steven M Taylor

Incorporating the relativistic all-angle Doppler shift equation in the interpretation of astronomical Doppler shift may help explain the Pioneer anomaly and other phenomena.

Kirstine Berg-Sorensen, Erwin J. G. Peterman, Tom Weber, Christoph F. Schmidt

In a typical optical tweezers detection system, the position of a trapped object is determined from laser light impinging on a quadrant photodiode. When the laser is infrared and the photodiode is of silicon, they can act together as an unintended low-pass filter. This parasitic effect is due to the high transparency of silicon to near-infrared light. A simp

A. I. Milstein, C. Müller, K. Z. Hatsagortsyan, U. D. Jentschura

The optical theorem is applied to the process of electron-positron pair creation in the superposition of a nuclear Coulomb and a strong laser field. We derive new representations for the total production rate as two-fold integrals, both for circular laser polarization and for the general case of elliptic polarization, which has not been treated before. Our a

Hector Aceves, Maria Colosimo

An introductory exposition of Chandrasekhar's gravitational dynamical friction, appropriate for an undergraduate class in mec hanics, is presented. This friction results when a massive particle moving through a ``sea'' of much lighter star particles experiences a retarding force du to an exchange of energy and momentum. General features of dynami

A. M. Selvam

The day-to day fluctuations of Dow Jones Index exhibit fractal fluctuations, namely, a zigzag pattern of successive increases followed by decreases on all space-time scales. Self-similar fractal fluctuations are generic to dynamical systems in nature and imply long-range space-time correlations. The apparently unpredictable (chaotic) fluctuations of dynamica

J. N. Orce, V. Velazquez

Shell model calculations have been carried out using the m-scheme numerical code {\small ANTOINE} in order to elucidate the particular trend of the isoscalar matrix elements, $M_0$, for $A=4n+2$ isobaric triplets ranging from A=18 to A=42. The 2${_1^+}_{(T=1)}$ $\to$ 0${_1^+}_{(T=1)}$ transition energies, reduced transition probabilities and isoscalar matrix

Ulf-G. Meißner, Udit Raha, Akaki Rusetsky

The extraction of the S-wave kaon-nucleon scattering lengths a0 and a1 from a combined analysis of existing kaonic hydrogen and synthetic deuterium data has been carried out within the framework of a low-energy effective field theory. It turns out that with the present DEAR central values for the kaonic hydrogen ground-state energy and width, a solution for

D. H. E. Gross

The physical meaning of entropy is analyzed in the context of statistical, nuclear, atomic physics and cosmology. Only the microcanonical Boltzmann entropy leads to no contradictions in several simple, elementary and for thermodynamics important situations. The conventional canonical statistics implies several serious errors and misinterpretations. This has

Mahir Hadzic

We use the compactness result of A. Burchard and Y. Guo (cf. \cite{BuGu}) to analyze the reduced 'energy' functional arising naturally in the stability analysis of steady states of the Vlasov-Poisson system (cf. \cite{SaSo} and \cite{Ha}). We consider the associated variational problem and present a new proof that puts it in the general framework for

Alexander Golubev

We propose to replace the classical Lorentz group with a compact semisimple Lie group. The results are rendered via the formalism of superspinors - objects identifiable as particles or antiparticles, and governed by the Fermi-Dirac statistics.

Bin Zhou, Xiaohua Zhu

In this paper, we discuss the relative $K$-stability and the modified $K$-energy associated to the Calabi's extremal metric on toric manifolds. We give a sufficient condition in the sense of convex polytopes associated to toric manifolds for both the relative $K$-stability and the properness of modified $K$-energy. In particular, our results hold for tor

Su Gao, Arnold W. Miller, William A. R. Weiss

We prove that there does not exist a subset of the plane S that meets every isometric copy of the vertices of the unit square in exactly one point. We give a complete characterization of all three point subsets F of the reals such that there does not exists a set of reals S which meets every isometric copy of F in exactly one point. A finite set X in the pla

Anurag K. Singh, Uli Walther

Let $(R,m)$ be a complete local ring of positive dimension, which contains a separably closed coefficient field of prime characteristic. Using a vanishing theorem of Peskine-Szpiro, Lyubeznik proved that every element of the local cohomology module $H^1_m(R)$ is killed by an iteration of the Frobenius map if and only if $R$ has dimension at least two and its

Vincent Vargas

In this article, we derive strong localization results for directed polymers in random environment. We show that at "low temperature" the polymer measure is asymptotically concentrated at a few points of macroscopic mass (we call these points epsilon-atoms). These results are derived assuming weak conditions on the tail decay of the random environmen

Mihai Caragiu, Jacob L. Johanssen

Both Fibonacci and Lucas numbers can be described combinatorially in terms of 0-1 strings without consecutive ones. In the present article we explore the occupation numbers as well as the correlations between various positions in the corresponding configurations.

Yuan Xu, Oleg Tischenko, Christoph Hoeschen

Attenuated Radon projections with respect to the weight function $W_μ(x,y) = (1-x^2-y^2)^{μ-1/2}$ are shown to be closely related to the orthogonal expansion in two variables with respect to $W_μ$. This leads to an algorithm for reconstructing two dimensional functions (images) from attenuated Radon projections. Similar results are established for reconstruc

Marc A. Coram

A Bayesian approach to the classification problem is proposed in which random partitions play a central role. It is argued that the partitioning approach has the capacity to take advantage of a variety of large-scale spatial structures, if they are present in the unknown regression function $f_0$. An idealized one-dimensional problem is considered in detail.

E. Feigin

In this paper we study an approximation of tensor product of irreducible integrable $\hat{\mathfrak{sl}_2}$ representations by infinite fusion products. This gives an approximation of the corresponding coset theories. As an application we represent characters of spaces of these theories as limits of certain restricted Kostka polynomials. This leads to the bo

Toufik Mansour, Simone Severini

A grid polygon is a polygon whose vertices are points of a grid. We define an injective map between permutations of length n and a subset of grid polygons on n vertices, which we call consecutive-minima polygons. By the kernel method, we enumerate sets of permutations whose consecutive-minima polygons satisfy specific geometric conditions. We deal with 2-var

Francesco Russo, Pierre Vallois

This paper first summarizes the foundations of stochastic calculus via regularization and constructs through this procedure Itô and Stratonovich integrals. In the second part, a survey and new results are presented in relation with finite quadratic variation processes, Dirichlet and weak Dirichlet processes.

J. van den Berg, R. Brouwer, B. Vagvolgyi

A few years ago two of us introduced, motivated by the study of certain forest-fireprocesses, the self-destructive percolation model (abbreviated as sdp model). A typical configuration for the sdp model with parameters p and delta is generated in three steps: First we generate a typical configuration for the ordinary percolation model with parameter p. Next,

Lex E. Renner

The factorial hull of the projective variety X (or its cone) is a graded algebra R(X) that can be used in some situations to consider simultaneously all divisor classes on X. Associated with X is a certain cone H in the divisor class group Cl(X) of X. We calculate H explicitly in the case where X is the plongement magnifique for the simple goup G. In this ca

Matthieu Willems

The aim of this paper is to give a recursive formula to multiply a line bundle with the structure sheaf of a schubert variety in the equivariant $K$-theory of a flag variety.

Guy Fayolle, Cyril Furtlehner

This report is the foreword of a series dedicated to stochastic deformations of curves. Problems are set in terms of exclusion processes, the ultimate goal being to derive hydrodynamic limits for these systems after proper scalings. In this study, solely the basic \textsc{asep} system on the torus is analyzed. The usual sequence of empirical measures, conver

Antoine Lejay, Miguel Martinez

The aim of this article is to provide a scheme for simulating diffusion processes evolving in one-dimensional discontinuous media. This scheme does not rely on smoothing the coefficients that appear in the infinitesimal generator of the diffusion processes, but uses instead an exact description of the behavior of their trajectories when they reach the points

Lucien Guillou

Let H be a homeomorphism of the open annulus isotopic to the identity which admits a lift h to the plane without fixed point. We show that h admits a Brouwer line which is a lift of a properly imbedded line joining one end to the other in the annulus or H admits a free essential simple closed curve.

Erwin Bolthausen, Nicola Kistler

We introduce a natural nonhierarchical version of Derrida's generalized random energy model. We prove that, in the thermodynamical limit, the free energy is the same as that of a suitably constructed GREM.

Clare D'Cruz

In this paper we find a formula for the length of a finitely supported complete ideal in terms of the order of the strict transform of the ideal. This formula was known for complete ideals of height two in a two dimensional regular local ring and was proved independently by Hoskin and Deligne. Several consequences are deduced from this formula.

R. A. Doney, A. E. Kyprianou

We obtain a new fluctuation identity for a general Lévy process giving a quintuple law describing the time of first passage, the time of the last maximum before first passage, the overshoot, the undershoot and the undershoot of the last maximum. With the help of this identity, we revisit the results of Klüppelberg, Kyprianou and Maller [Ann. Appl. Probab. 14

Sharad Goel

A deck of $n$ cards is shuffled by repeatedly moving the top card to one of the bottom $k_n$ positions uniformly at random. We give upper and lower bounds on the total variation mixing time for this shuffle as $k_n$ ranges from a constant to $n$. We also consider a symmetric variant of this shuffle in which at each step either the top card is randomly insert

Niels Richard Hansen

We define the reflection of a random walk at a general barrier and derive, in case the increments are light tailed and have negative mean, a necessary and sufficient criterion for the global maximum of the reflected process to be finite a.s. If it is finite a.s., we show that the tail of the distribution of the global maximum decays exponentially fast and de

Jim E. Hoste, Patrick D. Shanahan

A diagonal surface in a link exterior M is a properly embedded, incompressible, boundary incompressible surface which furthermore has the same number of boundary components and same slope on each component of the boundary of M. We derive a formula for the boundary slope of a diagonal surface in the exterior of a 2-bridge link which is analogous to the formul

Weiping Yin

Firstly, we consider the unitary geometry of two exceptional Cartan domains $\Re_{V}(16)$ and $\Re_{VI}(27)$. We obtain the explicit formulas of Bergman kernal funtion, Cauchy-Szegö kernel, Poinsson kernel and Bergman metric for $\Re_{V}(16)$ and $\Re_{VI}(27)$. Secondly, we give a class of invariant differential operators for Cartan domain $\Re$ of dimensio

Dan Margalit, Jon McCammond

We give several new positive finite presentations for the pure braid group that are easy to remember and simple in form. All of our presentations involve a metric on the punctured disc so that the punctures are arranged "convexly", which is why we describe them as geometric presentaitons. Motivated by a presentation for the full braid group that we c

Wenchuan Hu

In the first part of this paper, we show that the assertion "T_pH_k(X,Q)=G_pH_k(X,Q)" (which is called the Friedlander-Mazur conjecture) is a birationally invariant statement for smooth projective varieties X when p=dim(X)-2 and when p=1. We also establish the Friedlander-Mazur conjecture in certain dimensions. More precisely, for a smooth projective

V. Nikiforov, R. H. Schelp

We derive a number of extremal and Ramsey stability results for cycles.

Wenchuan Hu

Let X be a smooth projective variety of dimension n on which rational and homological equivalence coincide for algebraic p-cycles in the range 0\leq p\leq s. We show that the homologically trivial sector of rational Lawson homology L_pH_k(X,Q)_{hom} vanishes for 0\leq n-p\leq s+2. This is an analogue of a theorem of C. Peters in "dual dimensions". To

Debashish Goswami, Lingaraj Sahu

We investigate certain classes of normal completely positive (CP) maps on the hyperfinite $II_1$ factor $\mathcal A$. Using the representation theory of a suitable irrational rotation algebra, we propose some computable invariants for such CP maps.

Taeyoung Lee, Melvin Leok, N. Harris McClamroch

A global model is presented that can be used to study attitude maneuvers of a rigid spacecraft in a circular orbit about a large central body. The model includes gravity gradient effects that arise from the non-uniform gravity field and characterizes the spacecraft attitude with respect to the uniformly rotating local vertical local horizontal coordinate fra

Amir Dembo, Nina Gantert, Yuval Peres, Zhan Shi

Let $ξ(n, x)$ be the local time at $x$ for a recurrent one-dimensional random walk in random environment after $n$ steps, and consider the maximum $ξ^*(n) = \max_x ξ(n,x)$. It is known that $\limsup ξ^*(n)/n$ is a positive constant a.s. We prove that $\liminf_n (\log\log\log n)ξ^*(n)/n$ is a positive constant a.s.; this answers a question of P. Révész (1990)

Gabriel Baditoiu, Richard H. Escobales, Stere Ianus

Let $(M^{n},g)$ be a closed, connected, oriented, $C^{\infty}$, Riemannian, n-manifold with a transversely oriented foliation $\boldkey F$. We show that if $\lbrace X,Y \rbrace$ are basic vector fields, the leaf component of $[X,Y]$, $\Cal{V}[X,Y]$, has vanishing leaf divergence whenever $κ\wedge χ_{\boldkey F}$ is a closed (possibly zero) de Rham cohomology

Sarah J. Witherspoon

We obtain deformations of a crossed product of a polynomial algebra with a group, under some conditions, from universal deformation formulas. We show that the resulting deformations are nontrivial by a comparison with Hochschild cohomology. The universal deformation formulas arise from actions of Hopf algebras generated by automorphisms and skew derivations,

Gregory Gutin, Nick S. Jones, Arash Rafiey, Simone Severini

A digraph D=(V,A) is mediated if, for each pair x,y of distinct vertices of D, either xy belongs to A or yx belongs to A or there is a vertex z such that both xz,yz belong to A. For a digraph D, DELTA(D) is the maximum in-degree of a vertex in D. The "nth mediation number" mu(n) is the minimum of DELTA(D) over all mediated digraphs on n vertices. Med

David Gamarnik, Assaf Zeevi

We consider a single class open queueing network, also known as a generalized Jackson network (GJN). A classical result in heavy-traffic theory asserts that the sequence of normalized queue length processes of the GJN converge weakly to a reflected Brownian motion (RBM) in the orthant, as the traffic intensity approaches unity. However, barring simple instan

Tommaso de Fernex, Ernesto Lupercio, Thomas Nevins, Bernardo Uribe

Motivic integration and MacPherson's transformation are combined in this paper to construct a theory of "stringy" Chern classes for singular varieties. These classes enjoy strong birational invariance properties, and their definition encodes data coming from resolution of singularities. The singularities allowed in the theory are those typical of

D. Kaledin

We consider symplectic singularities in the sense of A. Beauville as examples of Poisson schemes. Using Poisson methods, we prove that a symplectic singularity admits a finite stratification with smooth symplectic strata. We also prove that in the formal neighborhood of a closed point in some stratum, the singularity is a product of the stratum and a transve

R. Loll, W. Westra, S. Zohren

The recent progress in the Causal Dynamical Triangulations (CDT) approach to quantum gravity indicates that gravitation is nonperturbatively renormalizable. We review some of the latest results in 1+1 and 3+1 dimensions with special emphasis on the 1+1 model. In particular we discuss a nonperturbative implementation of the sum over topologies in the gravitat

Eugenio R. Bezerra de Mello, Betti Hartmann

We study a 7-dimensional brane world scenario with a Ricci-flat 3-brane residing in the core of a composite monopole defect, i.e. a defect composed of a 'tHooft-Polyakov and a global monopole. Admitting a direct interaction between the two bosonic sectors of the theory, we analyse the structure of the space-time in the limits of small, respectively large

Yu-ichi Takamizu, Kei-ichi Maeda

We study collision of two domain walls in 5-dimensional asymptotically Anti de Sitter spacetime. This may provide the reheating mechanism of an ekpyrotic (or cyclic) brane universe, in which two BPS branes collide and evolve into a hot big bang universe. We evaluate a change of scalar field making the domain wall and can investigate the effect of a negative

Martin Land

In a relativistic classical and quantum mechanics with Poincare-invariant parameter, particle worldlines are traced out by the evolution of spacetime events. In pre-Maxwell electrodynamics -- the local gauge theory associated with this framework -- events induce five local off-shell fields, which mediate interactions between instantaneous events, not between

Marijn Davidse

We investigate membrane and fivebrane instanton effects in type IIA string theory compactified on rigid Calabi-Yau manifolds. These effects contribute to the low-energy effective action of the universal hypermultiplet, in four dimensional spacetime. To compute the nonperturbative effects due to the fivebrane instanton to the universal hypermultiplet, an inst

Eugen Radu, D. H. Tchrakian

Subjecting the SU(2) Yang--Mills system to azimuthal symmetries in both the $x-y$ and the $z-t$ planes results in a residual subsystem described by a U(1) Higgs like model with two complex scalar fields on the quarter plane. The resulting instantons are labeled by integers $(m,n_1,n_2)$ with topological charges $q=\frac12 [1-(-1)^m]n_1n_2$. Solutions are con

Noriko Shiiki, Nobuyuki Sawado, Shinsho Oryu

We consider the ${\cal N}=1$ Skyrme model and obtain supersymmetric skyrmion solutions numerically. The model necessarily contains higher derivative terms and as a result the field equation becomes a fourth-order differential equation. Solving the equation directly leads to runaway solutions as expected in higher derivative theories. We, therefore, apply the

A. B. Balantekin, J. H. de Jesus, R. Lazauskas, C. Volpe

We discuss the possibility of testing the weak currents and, in particular, the weak magnetism term through the measurement of the electron anti-neutrinos capture by protons at a low energy beta-beam facility. We analyze the sensitivity using both the total number of events and the angular distribution of the positrons emitted in a water Cerenkov detector. W

G. Bozzi, B. Fuks, M. Klasen

We perform a first precision calculation of the transverse-momentum (q_T) distribution of slepton pair and slepton-sneutrino associated production at the CERN Large Hadron Collider (LHC). We implement soft-gluon resummation at the next-to-leading logarithmic (NLL) level and consistently match the obtained result to the pure fixed-order perturbative result at

G. S. Danilov, L. N. Lipatov

We consider scattering amplitudes in string models in the Regge limit of high energies and fixed momentum transfers with the use of the unitarity in direct channels. Intermediate states are taken in the multi-Regge kinematics corresponding to the production of resonances with fixed invariant masses and large relative rapidities. In QCD such kinematics leads

K. J. Ozeren, W. J. Stirling

We study the QCD scattering amplitudes for \bar{q}q \to gg and \bar{q}q \to ggg where q is a massive fermion. Using a particular choice of massive fermion spinor we are able to derive very compact expressions for the partial spin amplitudes for the 2 \to 2 process. We then investigate the corresponding 2 \to 3 amplitudes using the BCFW recursion technique. F

Yoshio Koide

A shape of the unitary triangle versus a CP violating parameter δdepends on the phase conventions of the CKM matrix, because the CP violating parameter δcannot directly be observed, so that it is not rephasing-invariant. In order to seek for a clue to the quark mass matrix structure and the origin of the CP violation, the dependence of the unitary triangle s

B. P. Kersevan I. Hinchliffe

This paper addresses the issue of production of charm or bottom quarks in association with a high pT process in hadron hadron collision. These quarks can be produced either as part of the hard scattering process or as a remnant from the structure functions. The latter sums terms of the type (alpha_s log(pT/mq))^n. If structure functions of charm or bottom qu

Jose A. R. Cembranos, Jonathan L. Feng, Arvind Rajaraman, Bryan T. Smith

SuperWeakly-Interacting Massive Particles (superWIMPs) produced in the late decays of other particles are well-motivated dark matter candidates and may be favored over standard Weakly-Interacting Massive Particles (WIMPs) by small scale structure observations. Among the most promising frameworks that incorporate superWIMPs are R-parity conserving supersymmet

Christopher Lee, George Sterman

Nonperturbative effects in event shape distributions can be characterized by shape functions derived in the eikonal approximation or, equivalently, from soft-collinear effective theory. The use of energy flow operators and the boost invariance of the Wilson lines of soft gluons in the shape functions leads to a proof of universality for power corrections to

Christopher Lee

Soft-collinear effective theory (SCET) is used to demonstrate factorization for event shape distributions in the two-jet region. The leading nonperturbative power corrections to these distributions can be characterized as shape functions defined in terms of Wilson lines of soft gluons. The relation of these results to the well-known predictions for shifts in

Miguel A. Sanchis-Lozano

Heavy quarkonium decays can be used to search for New Physics beyond the Standard Model. In particular, a light Higgs boson could induce a slight (but observable) lepton universality breaking in Upsilon decays. In fact, current experimental data from CLEO presented in this Conference seem to point out to this direction within experimental accuracy. Moreover,

Kaustubh Agashe, Michele Papucci, Gilad Perez, Dan Pirjol

The flavor structure of a wide class of models, denoted as next to minimal flavor violation (NMFV), is considered. In the NMFV framework, new physics (NP), which is required for stabilization of the electroweak symmetry breaking (EWSB) scale, naturally couples (dominantly) to the third generation quarks and is quasi-aligned with the Yukawa matrices. Conseque

S. Dobbs, CLEO Collaboration

Using a sample of 3.08 million psi(2S) decays collected at sqrt{s} = 3.686 GeV with the CLEO detector at the Cornell Electron Storage Ring, we have measured the branching fractions for psi(2S) decays to pseudoscalar pairs pi+pi-, K+K-, and KsKl. We obtain B(psi(2S) -> pi+pi-) < 2.1 x 10^{-5} (90% C.L.), B(psi(2S) -> K+K-) = (6.3 +- 0.6(stat) +- 0.3(syst)) x

Teresa Barillari

The exclusive production of baryon-antibaryon pairs in the collisions of two quasi-real photons has been studied using different detectors at e+e- colliders. Results are presented for $γγ\to$ proton antiproton, $γγ\toΛ\barΛ$, and $γγ\to Σ^{0}\bar{Σ^{0}}$ final states. The cross-section measurements are compared with all the existing experimental data and wit

M. Tajmar, F. Plesescu, K. Marhold, C. J. de Matos

It is well known that a rotating superconductor produces a magnetic field proportional to its angular velocity. The authors conjectured earlier, that in addition to this so-called London moment, also a large gravitomagnetic field should appear to explain an apparent mass increase of Niobium Cooper-pairs. This phenomenon was indeed observed and induced accele

E. Huguet, J. Queva, J. Renaud

In this paper we write down the equation for a scalar conformally coupled field simultaneously for de Sitter (dS), anti-de Sitter (AdS) and Minkowski spacetime in d-dimensions. The curvature dependence appears in a very simple way through a conformal factor. As a consequence the process of curvature free limit, including wave functions limit and two-points f

V. J. Bolós

We state a condition for an observer to be comoving with another observer in general relativity, based on the concept of lightlike simultaneity. Taking into account this condition, we study relative velocities, Doppler effect and light aberration. We obtain that comoving observers observe the same light ray with the same frequency and direction, and so gravi

Willie L. Scott

A method of autonomic face recognition based on the biologically plausible network of networks (NoN) model of information processing is presented. The NoN model is based on locally parallel and globally coordinated transformations in which the neurons or computational units form distributed networks, which themselves link to form larger networks. This models

S. Hemachander, Amit Verma, Siddharth Arora, Prasanta K. Panigrahi

We present an algorithm that enables one to perform locally adaptive block thresholding, while maintaining image continuity. Images are divided into sub-images based some standard image attributes and thresholding technique is employed over the sub-images. The present algorithm makes use of the thresholds of neighboring sub-images to calculate a range of val

Wei Dai, Youjian Liu, Vincent K. N. Lau, Brian Rider

It is well known that Multiple-Input Multiple-Output (MIMO) systems have high spectral efficiency, especially when channel state information at the transmitter (CSIT) is available. When CSIT is obtained by feedback, it is practical to assume that the channel state feedback rate is finite and the CSIT is not perfect. For such a system, we consider beamforming

Haya El-Ghalayini, Mohammed Odeh, Richard McClatchey

This paper studies the role that ontologies can play in establishing conceptual data models during the process of information systems development. A mapping algorithm has been proposed and embedded in a special purpose Transformation-Engine to generate a conceptual data model from a given domain ontology. In addition, this paper focuses on applying the propo

Andreas Herzig, Ivan Varzinczak

Consistency check has been the only criterion for theory evaluation in logic-based approaches to reasoning about actions. This work goes beyond that and contributes to the metatheory of actions by investigating what other properties a good domain description in reasoning about actions should have. We state some metatheoretical postulates concerning this sore

Vaghinak Petrosyan

Modern frameworks for development of graphical interfaces are using the native controls of the operating system. Because of that they are using operating system events model for inter-component communication. We consider a method to increase inter-component communication speed by sending messages from one component to the other passing over the operating sys

Wei Dai, Youjian Liu, Brian Rider

We analyze the performance of CDMA signature optimization with finite rate feedback. For a particular user, the receiver selects a signature vector from a signature codebook to avoid the interference from other users, and feeds the corresponding index back to this user through a finite rate and error-free feedback link. We assume the codebook is randomly con

Michael T. Gastner, M. E. J. Newman

We consider the problem of constructing public facilities, such as hospitals, airports, or malls, in a country with a non-uniform population density, such that the average distance from a person&#39;s home to the nearest facility is minimized. Approximate analytic arguments suggest that the optimal distribution of facilities should have a density that increa

Moon-Ho Jo, Jacob E. Grose, Kanhayalal Baheti, Mandar M. Deshmukh

Single-molecule transistors provide a unique experimental tool to investigate the coupling between charge transport and the molecular degrees of freedom in individual molecules. One interesting class of molecules for such experiments are the single-molecule magnets, since the intramolecular exchange forces present in these molecules should couple strongly to

Sara E. Mason, Ilya Grinberg, Andrew M. Rappe

We demonstrate that variations in molecular chemisorption energy on different metals, different surface terminations, and different strain conditions can be accounted for by orbital-specific changes in the substrate electronic structure. Our density functional theory data set, spanning three metals, two surface terminations, and five strain states, is fit to

Andre A. Moreira, Demetrius R. Paula, Raimundo N. Costa Filho, Jose S. Andrade

Understanding the process by which the individuals of a society make up their minds and reach opinions about different issues can be of fundamental importance. In this work we propose an idealized model for competitive cluster growth in complex networks. Each cluster can be thought as a fraction of a community that shares some common opinion. Our results sho

Rahul Roy

A square lattice model which exhibits a nonzero quantized Hall conductance in a zero net magnetic field at certain values of the parameters is presented. The quantization is due to the existence of a topological winding number that characterizes the quantum Hall phases and is expected to survive the effects of weak disorder.

G. M. Falco, H. T. C. Stoof

We present a detailed analysis of the two-channel atom-molecule effective Hamiltonian for an ultracold two-component homogeneous Fermi gas interacting near a Feshbach resonance. We particularly focus on the two-body and many-body properties of the dressed molecules in such a gas. An exact result for the many-body T-matrix of the two-channel theory is derived

Peter D. Duncan, Philip J. Camp

The kinetics of aggregation in a monolayer of magnetic particles are studied using stochastic dynamics computer simulations. At low densities (<8% coverage) the equilibrium structure is made up of chains and rings; the primary mechanisms by which these motifs form are described. At higher densities (>15% coverage), we observe large transient concentrations o