August 2004 arXiv papers — page 12

Mike Develin, Bernd Sturmfels

The notions of convexity and convex polytopes are introduced in the setting of tropical geometry. Combinatorial types of tropical polytopes are shown to be in bijection with regular triangulations of products of two simplices. Applications to phylogenetic trees are discussed. Theorem 29 and Corollary 30 in the paper, relating tropical polytopes to injective

Chunhui Lai

In this paper we consider a variation of the classical Turán-type extremal problems. Let $S$ be an $n$-term graphical sequence, and $σ(S)$ be the sum of the terms in $S$. Let $H$ be a graph. The problem is to determine the smallest even $l$ such that any $n$-term graphical sequence $S$ having $σ(S)\ge l$ has a realization containing $H$ as a subgraph. Denote

Yuan-Ben Dai, Chun Liu, Y. -R. Liu, Shi-Lin Zhu

We analyze various possible interpretations of the narrow state $D_{sJ}^+(2632)$ observed by SELEX Collaboration recently, which lies above threshold and has abnormal decay pattern. These interpretations include: (1) several versions of tetraquarks; (2) conventional $c\bar s$ meson such as the first radial excitation of $D_s(2112)$ with abnormally large SU(3

Amir H. Rezaeian, Niels R. Walet, Michael C. Birse

We study the nucleon and diquarks in a non-local Nambu-Jona-Lasinio model. For certain parameters the model exhibits quark confinement, in the form of a propagator without real poles. After truncation of the two-body channels to the scalar and axial-vector diquarks, a relativistic Faddeev equation for nucleon bound states is solved in the covariant diquark-q

Jonathan L. Rosner

The non-$D \bar D$ decays of the $\ppp = ψ(3770)$ resonance are reviewed and possibilities for further measurements are noted. These decays can shed light on S--D mixing, the ``missing'' $ψ' = ψ(3686)$ decays, a possible discrepancy between the total and $D \bar D$ cross sections at the $\ppp$, and rescattering effects contributing to enhanced $b

Marek Tasevsky

The physics potential of the forward physics project at CMS is very rich. Some of the diffraction and low-x physics channels are briefly discussed.

K. Abe

We present results of a study of the charmless vector-vector decays B^0 -> K^{*0} rho^0 and B^+ ->K^{*0} rho^+. The results are based on a 140 fb^{-1} data sample collected by the Belle detector at the KEKB asymmetric e^+e^- collider. We obtain the branching fraction B(B^+ -> K^{*0} rho^+)=(6.6 +- 2.2(stat.) +- 0.8 (syst.)) x 10^{-6}, and set upper limits on

Daniel Yacob

The Metaphone algorithm applies the phonetic encoding of orthographic sequences to simplify words prior to comparison. While Metaphone has been highly successful for the English language, for which it was designed, it may not be applied directly to Ethiopian languages. The paper details how the principles of Metaphone can be applied to Ethiopic script and us

Zhimao Guo, Min Li, Xiaoling Wang, Aoying Zhou

XSLT is an increasingly popular language for processing XML data. It is widely supported by application platform software. However, little optimization effort has been made inside the current XSLT processing engines. Evaluating a very simple XSLT program on a large XML document with a simple schema may result in extensive usage of memory. In this paper, we p

Stephen Luttrell

In this paper it is shown how to map a data manifold into a simpler form by progressively discarding small degrees of freedom. This is the key to self-organising data fusion, where the raw data is embedded in a very high-dimensional space (e.g. the pixel values of one or more images), and the requirement is to isolate the important degrees of freedom which l

B. Andrei Bernevig, Oskar Vafek

We predict the appearance of a uniform magnetization in strained three dimensional p-doped semiconductors with inversion symmetry breaking subject to an external electric field. We compute the magnetization response to the electric field as a function of the direction and magnitude of the applied strain. This effect could be used to manipulate the collective

G. -H. Gweon, S. Y. Zhou, A. Lanzara

The sudden change of the velocity, so-called "kink," of the dispersing peak in angle resolved photoelectron spectroscopy is a well-known feature in the high temperature superconducting cuprates. Currently, the origin of the kink is being much debated, but a consensus has not emerged yet. Here, we present a study of the momentum evolution of the kink

A. D. Drozdov

The elastic response is studied of a single flexible chain grafted on a rigid plane and an ensemble of non-interacting tethered chains. It is demonstrated that the entropic theory of rubber elasticity leads to conclusions that disagree with experimental data. A modification of the conventional approach is proposed, where the end-to-end distribution function

K. V. McCloud, U. Cardak, M. L. Kurnaz

The roughness exponent of surfaces obtained by dispersing silica spheres into a quasi-two-dimensional cell is examined using experimental and computational methods. The cell consists of two glass plates separated by a gap, which is comparable in size to the diameter of the beads. We have studied the effect of changing the gap between the plates to a limit of

S. Lehmann, A. D. Jackson, B. Lautrup

Scientific communities are characterized by strong stratification. The highly skewed frequency distribution of citations of published scientific papers suggests a relatively small number of active, cited papers embedded in a sea of inactive and uncited papers. We propose an analytically soluble model which allows for the death of nodes. This model provides a

G. -H. Gweon, S. -K. Mo, J. W. Allen, J. He

Angle resolved photoemission spectroscopy line shapes measured for quasi-one-dimensional Li$_{0.9}$Mo$_6$O$_{17}$ samples grown by a temperature gradient flux technique are found to show Luttinger liquid behavior, consistent with all previous data by us and other workers obtained from samples grown by the electrolyte reduction technique. This result eliminat

David Hiriart, Luis Salas, Irene Cruz-Gonzalez

We present the radial velocity structure of the molecular hydrogen outflows associated to the star forming region Cepheus A. This structure is derived from doppler shift of the H_2 v=1-0 S(1) emission line obtained by Fabry-Perot spectroscopy. The East and West regions of emission, called Cep A(E) and Cep A(W), show radial velocities in the range -20 to 0 km

Wenjin Mao, Dmitri V. Averin, Francesco Plastina, Rosario Fazio

We develop a theory of coherent quantum oscillations in two, in general interacting, qubits measured continuously by a mesoscopic detector with arbitrary non-linearity and discuss an example of SQUID magnetometer that can operate as such a detector. Calculated spectra of the detector output show that the detector non-linearity should lead to mixing of the os

Stefano Chiantese, Florian Gmeiner, Claus Jeschek

We consider topological sigma models with generalized Kahler target spaces. The mirror map is constructed explicitly for a special class of target spaces and the topological A and B model are shown to be mirror pairs in the sense that the observables, the instantons and the anomalies are mapped to each other. We also apply the construction to open topologica

Ruggero Ferrari, Andrea Quadri

We discuss the problem of unitarity for Yang-Mills theory in the Landau gauge with a mass term a la Stueckelberg. We assume that the theory (non-renormalizable) makes sense in some subtraction scheme (in particular the Slavnov-Taylor identities should be respected!) and we devote the paper to the study of the space of the unphysical modes. We find that the t

Wung-Hong Huang

The quantum stress-energy tensor of a massless scalar field propagating in the two-dimensional Vaidya-de Sitter metric, which describes a classical model spacetime for a dynamical evaporating black hole in an inflationary universe, is analyzed. We present a possible way to obtain the Hawking radiation terms for the model with arbitrary functions of mass. It

Tomoya Takiwaki, Kei Kotake, Shigehiro Nagataki, Katsuhiko Sato

We perform a series of two-dimensional magnetohydrodynamic simulations of the rotational core-collapse of a magnetized massive star. We employ a realistic equation of state and take into account the neutrino cooling by the so-called leakage scheme. In this study we systematically investigate how the strong magnetic field and the rapid rotation affect the pro

Y. Chao

We report evidence for direct CP violation in the decay B0 -> K+-pi-+ with 253/fb of data collected with the Belle detector at the KEKB e+e- collider. Using 275 million B B_bar pairs we observe a B -> K+-pi-+ signal with 2140+-53 events. The measured CP violating asymmetry is Acp(K+-pi-+) = -0.101+-0.025 (stat)+-0.005 (syst), corresponding to a significance

Adel Bririd, Simon C. Benjamin, Alastair Kay

An interesting concept in quantum computation is that of global control (GC), where there is no need to manipulate qubits individually. One can implement a universal set of quantum gates on a one-dimensional array purely via signals that target the entire structure indiscriminately. But large-scale quantum computation imposes several requirements in terms of

Reginald T. Cahill

The Gravity Probe B (GP-B) satellite experiment will measure the precession of on-board gyroscopes to extraordinary accuracy. Such precessions are predicted by General Relativity (GR), and one component of this precession is the `frame-dragging' or Lense-Thirring effect, which is caused by the rotation of the earth. A new theory of gravity, which passes

J. Adam, V. P. Garistov, M. Honusek, J. Dobes

Reduced probabilities B(E2) of γtransitions between states of positive parity in the ^160Dy nucleus are calculated within the framework of the interacting boson model (IBM-1). The results are compared with the experimental data.

Masayuki Matsuo, Kazuhito Mizuyama, Yasuyoshi Serizawa

The neutron pairing correlation and the soft dipole excitation in medium-mass nuclei near drip-line are investigated from a viewpoint of the di-neutron correlation. Numerical analyses by means of the coordinate-space HFB and the continuum QRPA methods are performed for even-even $^{18-24}$O, $^{50-58}$Ca and $^{80-86}$Ni. A clear signature of the di-neutron

Thomas Guhr, Heiner Kohler

We show that Calogero-Sutherland models for interacting particles have a natural supersymmetric extension. For the construction, we use Jacobians which appear in certain superspaces. Some of the resulting Hamiltonians have a direct physics interpretation as models for two kinds of interacting particles. One model may serve to describe interacting electrons i

Artur Avila, Mikhail Lyubich

We show that contrary to anticipation suggested by the dictionary between rational maps and Kleinian groups and by the ``hairiness phenomenon'', there exist many Feigenbaum Julia sets $J(f)$ whose Hausdorff dimension is strictly smaller than two. We also prove that for any Feigenbaum Julia set, the Poincaré critical exponent $\de_\crit$ is equal to t

Alex Iosevich, Mischa Rudnev

We study the Erdos distance conjecture on the unit sphere in three dimensions using Fourier analytic methods.

Vicentiu Pasol, Alexander Polishchuk

Generalizing math.AG/0003076 we express universal triple Massey products between line bundles on elliptic curves in terms of Hecke's indefinite theta series. We show that all Hecke's indefinite theta series arise in this way.

Thomas W. Mattman, Ryan Ottman, Matt Rodrigues

We classify graphs that are 0, 1, or 2 edges short of being complete partite graphs with respect to intrinsic linking and intrinsic knotting. In addition, we classify intrinsic knotting of graphs on 8 vertices. For graphs in these families, we verify a conjecture presented in Adams' "The Knot Book": If a vertex is removed from an intrinsically kn

Samson Saneblidze, Ronald Umble

We construct an explicit diagonal Δ_P on the permutahedra P. Related diagonals on the multiplihedra J and the associahedra K are induced by Tonks' projection P --> K and its factorization through J. We introduce the notion of a permutahedral set Z and lift Δ_P to a diagonal on Z. We show that the double cobar construction Ω^2(C_*(X)) is a permutahedral s

Alexander Polishchuk

We apply the homological mirror symmetry for elliptic curves to the study of indefinite theta series. We prove that every such series corresponding to a quadratic form of signature (1,1) can be expressed in terms of theta series associated with split quadratic forms and the usual theta series. We also show that indefinite theta series corresponding to unival

Brian Forbes

We study geometric transitions on Calabi- Yau manifolds from the perspective of the $B$ model. Looking toward physically motivated predictions, it is shown that the traditional conifold transition is too simple a case to yield meaningful results. The mathematics of a nontrivial example (of Aganagic and Vafa) is worked out carefully, and the expected equivale

Chryssomalis Chryssomalakos

A number of problems in theoretical physics share a common nucleus of combinatoric nature. It is argued here that Hopf algebraic concepts and techiques can be particularly efficient in dealing with such problems. As a first example, a brief review is given of the recent work of Connes, Kreimer and collaborators on the algebraic structure of the process of re

Hsiang-nan Li

I review recent progress on exclusive $B$ meson decays made in the perturbative QCD approach, concentrating on the evolution of the $B$ meson wave function in $k_T$ factorization, radiative decays, polarizations in $VV$ modes, and new physics effect in $B\to ϕK_S$.

Massimo Tinto, Malik Rakhmanov

LISA is an array of three spacecraft flying in an approximately equilateral triangle configuration, which will be used as a low-frequency detector of gravitational waves. Recently a technique has been proposed for suppressing the phase noise of the onboard lasers by locking them to the LISA arms. In this paper we show that the delay-induced effects substanti

Stephen Luttrell

The theory of stochastic vector quantisers (SVQ) has been extended to allow the quantiser to develop invariances, so that only "large" degrees of freedom in the input vector are represented in the code. This has been applied to the problem of encoding data vectors which are a superposition of a "large" jammer and a "small" signal, so

Stephen Luttrell

In this paper a stochastic generalisation of the standard Linde-Buzo-Gray (LBG) approach to vector quantiser (VQ) design is presented, in which the encoder is implemented as the sampling of a vector of code indices from a probability distribution derived from the input vector, and the decoder is implemented as a superposition of reconstruction vectors. This

John David Funge

This paper describes a new breed of academic journals that use statistical machine learning techniques to make them more democratic. In particular, not only can anyone submit an article, but anyone can also become a reviewer. Machine learning is used to decide which reviewers accurately represent the views of the journal's readers and thus deserve to hav

Hiroyuki Yamase

Several instabilities competing with the d-wave singlet pairing were proposed for high-Tc cuprates. One of them is the d-wave Fermi surface deformation (dFSD), which is generated by forward scattering. In this paper, correlation functions of the dFSD are calculated within the random phase approximation. In the normal state, the excitation spectrum shows a lo

Tin-Lun Ho, Neldeltcho Zahariev

We show that the high temperature behavior of atomic gases near Feshbach Resonance with non-zero orbital angular momentum $(\ell >0)$ belong to a universality class different from that of s-wave resonances. The universal interaction energy is $2(2\ell +1)$ times larger than that of the s-wave when approaching the resonance from the atomic side, but is essent

Tin-Lun Ho, Roberto B. Diener

We study the pairing of Fermi gases near the scattering resonance of the $\ell\neq 0$ partial wave. Using a model potential which reproduces the actual two-body low energy scattering amplitude, we have obtained an analytic solution of the gap equation. We show that the ground state of $\ell=1$ and $\ell=3$ superfluid are orbital ferromagnets with pairing wav

W. B. Wu, D. J. Huang, J. Okamoto, A. Tanaka

Measurements of polarization-dependent soft x-ray absorption reveal that the electronic states determining the low-energy excitations of Na$_{x}$CoO$_2$ have predominantly $a_{1g}$ symmetry with significant O $2p$ character. A large transfer of spectral weight observed in O $1s$ x-ray absorption provides spectral evidence for strong electron correlations in

Matthias Vojta, Subir Sachdev

Motivated by recent neutron scattering experiments on the cuprate superconductors, we present a phenomenological framework describing the dynamics of collective spin excitations coupled to charge/bond order fluctuations. Our quantum lattice model contains two order parameter fields, and can capture spin excitations both in broken-symmetry states with static

Falk Herwig, Sam M. Austin

We have studied how the third dredge-up and the carbon star formation in low-mass Asymptotic Giant Branch stars depends on certain key nuclear reaction rates. We find from a set of complete stellar evolution calculations of a 2Msun model with Z=0.01 including mass loss, that varying either the N14(p,g)O15 or the 3-alpha reaction rate within their uncertainti

N. G. Guseva, P. Papaderos, Y. I. Izotov, K. G. Noeske

We present a ground-based optical spectroscopic and HST U, V, I photometric study of the blue compact dwarf (BCD) galaxy Pox 186. It is found that the emission of the low-surface brightness (LSB) component in Pox 186 at radii < 3&#39;&#39; (< 270 pc in linear scale) is mainly gaseous in origin. We detect Halpha emission out to radii as large as 6&#39;&#39;.

Y. I. Izotov, P. Papaderos, N. G. Guseva, K. J. Fricke

We present VLT spectroscopic observations with different spectral resolutions and different slit orientations of the two metal-deficient blue compact dwarf (BCD) galaxies Tol 1214-277 and Tol 65. The oxygen abundances in the brightest HII regions of Tol 1214-277 and Tol 65 are found to be 12+log O/H = 7.55+/-0.01 and 7.54+/-0.01, or Zsun/24. The nitrogen-to-

Y. I. Izotov, T. X. Thuan

We present V and I photometry of the resolved stars in the most metal-deficient blue compact dwarf galaxy known, I Zw 18 (Zsun/50), using Hubble Space Telescope/Advanced Camera for Surveys (ACS) images, the deepest ones ever obtained for this galaxy. The resulting I vs. V-I color-magnitude diagram (CMD) reaches limiting magnitudes V=I=29 mag. It reveals a yo

W. K. M. Rice, G. Lodato, J. E. Pringle, P. J. Armitage

In this paper we consider the evolution of small planetesimals in marginally stable, self-gravitating protoplanetary discs. The drag force between the disc gas and the embedded planetesimals generally causes the planetesimals to drift inwards through the disc at a rate that depends on the particle size. In a marginally stable, self-gravitating disc, however,

N. Christlieb, T. C. Beers, P. S. Barklem, M. Bessell

We report on a dedicated effort to identify and study metal-poor stars strongly enhanced in r-process elements ([r/Fe] > 1 dex; hereafter r-II stars), the Hamburg/ESO R-process Enhanced Star survey (HERES). Moderate-resolution (~2A) follow-up spectroscopy has been obtained for metal-poor giant candidates selected from the Hamburg/ESO objective-prism survey (

K. Tsuji, S. Nakamura, T. Sato, K. Kubodera

We study the effect of the neutrino magnetic moment on the neutrino-deuteron breakup reaction, using a method called the standard nuclear physics approach, which has already been well tested for several electroweak processes involving the deuteron.

Joseph M. Renes

We prove the existence of equiangular tight frames having n=2d-1 elements drawn from either C^d or C^(d-1) whenever n is either 2^k-1 for k in N, or a power of a prime such that n=3 mod 4. We also find a simple explicit expression for the prime power case by establishing a connection to a 2d-element equiangular tight frame based on quadratic residues.

R. O&#39;Shaughnessy, V. Kalogera, K. Belczynski

Formation rates of compact-object binaries are often derived from population synthesis calculations. However, such calculations depend sensitively on a relatively large number of model input parameters. Given considerable uncertainty in those model parameters, the predicted inspiral rates for double compact objects relevant to gravitational-wave interferomet

A. Mandilara, J. W. Clark

The most basic scenario of quantum control involves the organized manipulation of pure dynamical states of the system by means of unitary transformations. Recently, Vilela Mendes and Mank&#39;o have shown that the conditions for controllability on the state space become less restrictive if unitary control operations may be supplemented by projective measurem

Shardha Jogee

In this chapter, I review the fueling and evolution of active galactic nuclei (AGN) under the influence of internal and external triggers, namely intrinsic properties of host galaxies (morphological or Hubble type, color, presence of bars and other non-axisymmetric features, etc) and external factors such as environment and interactions. The most daunting ch

S. Jogee, F. D. Barazza, H. -W. Rix, I. Shlosman

One third of present-day spirals host optically visible strong bars that drive their dynamical evolution. However, the fundamental question of how bars evolve over cosmological times has yet to be addressed, and even the frequency of bars at intermediate redshifts remains controversial. We investigate the frequency of bars out to z~1.0 drawing on a sample of

Konstantin G. Zloshchastiev

The exactly solvable scalar hairy black hole model (originated from the modern high-energy theory) is proposed. It turns out that the existence of black holes (BH) is strongly correlated to global scalar field, in a sense that they mutually impose bounds upon their physical parameters like the BH mass (lower bound) or the cosmological constant (upper bound).

Edwin Barnes, Ken Intriligator, Brian Wecht, Jason Wright

In earlier work, we (KI and BW) gave a two line &#34;almost proof&#34; (for supersymmetric RG flows) of the weakest form of the conjectured 4d a-theorem, that a_{IR}<a_{UV}, using our result that the exact superconformal R-symmetry of 4d SCFTs maximizes a=3Tr R^3-Tr R. The proof was incomplete because of two identified loopholes: theories with accidental sym

L. D. Carr, Charles W. Clark

The form and stability properties of axisymmetric and spherically symmetric stationary states in two and three dimensions, respectively, are elucidated for Bose-Einstein condensates. These states include the ground state, central vortices, and radial excitations of both. The latter are called ring solitons in two dimensions and spherical shells in three. The

Nelia Mann, Joseph Polchinski

We study states of large charge density in integrable conformal coset models. For the O(2) coset, we consider two different S-matrices, one corresponding to a Thirring mass perturbation and the other to the continuation to O(2+epsilon). The former leads to simplification in the conformal limit; the latter gives a more complicated description of the O(2) syst

John Greaves

A list of 705 new Northern Celestial Hemisphere common proper motion pairs as derived from the Second U.S. Naval Observatory CCD Astrograph Catalog is presented, along with details of their separation, motion, brightness and colour. Objects of particular interest are noted, and the use of the catalogue for such work gauged.

Thomas Szkopek, Vwani Roychowdhury, Eli Yablonovitch, Daniel S. Abrams

We demonstrate how linear differential operators could be emulated by a quantum processor, should one ever be built, using the Abrams-Lloyd algorithm. Given a linear differential operator of order 2S, acting on functions psi(x_1,x_2,...,x_D) with D arguments, the computational cost required to estimate a low order eigenvalue to accuracy Theta(1/N^2) is Theta

Eric Braaten

If the X(3872) is a loosely-bound D^{*0} Dbar^0 / D^0 Dbar^{*0} molecule, its inclusive production rate can be described by the NRQCD factorization formalism that applies to inclusive quarkonium production. We argue that if the molecule has quantum numbers J^{PC} = 1^{++}, the most important term in the factorization formula should be the color-octet ^3S_1 t

Paolo Messina

Few examples of the exploitation of molecular magnetic properties in molecular electronics are known to date. Here we propose the realization of Self assembled monolayers (SAM) of a particular stable organic radical. This radical is meant to be used as a standard molecule on which to prove the validity of a single spin reading procedure known as ESR-STM. We

Paolo Messina, Paolo Sigalotti, Lorenzo Lenci, Matteo Mannini

Reading and manipulating the spin status of single magnetic molecules is of paramount importance both for applicative and fundamental purposes. The possibility to combine Electron Spin Resonance (ESR) and Scanning Tunnelling Microscopy (STM) has been explored one decade ago. A few experiments have raised the question whether or not an EPR spectrum of single

Michael T. Anderson

A new proof of Friedrich&#39;s theorem on the existence and stability of asymptotically de Sitter spaces in 3+1 dimensions is given, which extends to all even dimensions. In addition, we characterize the possible limits of spaces which are globally asymptotically de Sitter, to the past and future.

Thomas Heistracher, Thomas Kurz, Claudius Masuch, Pierfranco Ferronato

In this paper we present ideas and architectural principles upon which we are basing the development of a distributed, open-source infrastructure that, in turn, will support the expression of business models, the dynamic composition of software services, and the optimisation of service chains through automatic self-organising and evolutionary algorithms deri

Oleg Andreev

We study the Regge limit of string amplitudes within the model of Polchinski-Strassler for string scattering in warped spacetimes. We also present some numerical estimations of the Regge slopes. It is quite remarkable that the real values of the slopes are inside a range of ours.

K. I. Caputi, J. S. Dunlop, R. J. McLure, N. D. Roche

We present estimated redshifts and derived properties for a sample of 1663 galaxies with Ks <= 22 (Vega), selected from 50.4 sq.arcmin of the GOODS/CDFS field with deep ISAAC imaging, and make an extensive comparison of their properties with those of the extremely red galaxies (ERGs) selected in the same field. We study in detail the evolution of Ks-selected

Christian Schori, Thilo Stöferle, Henning Moritz, Michael Köhl

We prepare a Bose-Einstein condensed gas in a three-dimensional optical lattice and study the excitation spectrum of the superfluid phase for different interaction strengths. We probe the response of the system by modulating the depth of the optical lattice along one axis. The interactions can be controlled independently by varying the tunnel coupling along

Leszek Roszkowski, Roberto Ruiz de Austri, Ki-Young Choi

In the framework of the CMSSM we study the gravitino as the lightest supersymmetric particle and the dominant component of cold dark matter in the Universe. We include both a thermal contribution to its relic abundance from scatterings in the plasma and a non--thermal one from neutralino or stau decays after freeze--out. In general both contributions can be

C. Semay, F. Brau, B. Silvestre-Brac

The masses of pentaquarks $uudd\bar s$ are calculated within the framework of a semirelativistic effective QCD Hamiltonian, using a diquark picture. This approximation allows a correct treatment of the confinement, assumed here to be similar to a Y-junction. With only color antitriplet diquarks, the mass of the pentaquark candidate $Θ$ with positive parity i

Yuuiti Sendouda, Kazunori Kohri, Shigehiro Nagataki, Katsuhiko Sato

We investigate cosmic-ray antiprotons emitted from the galactic primordial black holes in the Randall-Sundrum type-2 braneworld. The recent results of the BESS antiproton observation implies the existence of exotic primary sub-GeV antiprotons, one of whose most probable origin is PBHs in Our Galaxy. We show that the magnitude of antiproton flux from PBHs in

K. Gallmeister, W. Cassing

Within a hadron-string dynamical transport approach (HSD) we investigate the attenuation of high transverse momentum ($\pT$) hadrons as well as the suppression of &#39;near-side&#39; and &#39;far-side&#39; jets in $Au+Au$ collisions at invariant energies $\sqrt{s}$ = 200 GeV and $\sqrt{s}$ = 62.4 GeV in comparison to the data available from the Relativistic

Lu Guo, Fumihiko Sakata, Enguang Zhao

Within the constrained Hartree-Fock (CHF) theory, an analytic condition is derived to estimate whether a concept of the self-consistent mean field is realized or not in level repulsive region. The derived condition states that an iterative calculation of CHF equation does not converge when the quantum fluctuations coming from two-body residual interaction an

Yuzuru Sato, Eizo Akiyama, James P. Crutchfield

We derive a class of macroscopic differential equations that describe collective adaptation, starting from a discrete-time stochastic microscopic model. The behavior of each agent is a dynamic balance between adaptation that locally achieves the best action and memory loss that leads to randomized behavior. We show that, although individual agents interact w

Hiromi Otsuka, Yutaka Okabe

We study a square-lattice three-state Potts antiferromagnet with a staggered polarization field at finite temperature. Numerically treating the transfer matrices, we determine two phase boundaries separating the model-parameter space into three parts. We confirm that one of them belongs to the ferromagnetic three-state Potts criticality, which is in accord w

Jing Cheng, Shensheng Han

Entangled-photon coincidence imaging is a method to nonlocally image an object by transmitting a pair of entangled photons through the object and a reference optical system, respectively. The image of the object can be extracted from the coincidence rate of these two photons. From a classical perspective, the image is proportional to the fourth-order correla

Jaroslav Řeháček, Berthold-Georg Englert, Dagomir Kaszlikowski

We present an iterative algorithm that finds the optimal measurement for extracting the accessible information in any quantum communication scenario. The maximization is achieved by a steepest-ascent approach toward the extremal point, following the gradient uphill in sufficiently small steps. We apply it to a simple ad-hoc example, as well as to a problem w

A. Ruschhaupt, J. G. Muga

An atom diode, i.e., a device that lets the ground state atom pass in one direction but not in the opposite direction in a velocity range is devised. It is based on the adiabatic transfer achieved with two lasers and a third laser potential that reflects the ground state.

Ali Mostafazadeh, Ahmet Batal

For a non-Hermitian Hamiltonian H possessing a real spectrum, we introduce a canonical orthonormal basis in which a previously introduced unitary mapping of H to a Hermitian Hamiltonian h takes a simple form. We use this basis to construct the observables O of the quantum mechanics based on H. In particular, we introduce pseudo-Hermitian position and momentu

Shao-Ming Fei, Zhi-Xi Wang, Hui Zhao

We discuss a kind of generalized concurrence for a class of high dimensional quantum pure states such that the entanglement of formation is a monotonically increasing convex function of the generalized concurrence. An analytical expression of the entanglement of formation for a class of high dimensional quantum mixed states is obtained.

Christopher M. Dawson, Henry L. Haselgrove, Andrew P. Hines, Duncan Mortimer

What is the computational power of a quantum computer? We show that determining the output of a quantum computation is equivalent to counting the number of solutions to an easily computed set of polynomials defined over the finite field Z_2. This connection allows simple proofs to be given for two known relationships between quantum and classical complexity

P. Coullet, L. Mahadevan, C. S. Riera

We give a hydrodynamical explanation for the chaotic behaviour of a dripping faucet using the results of the stability analysis of a static pendant drop and a proper orthogonal decomposition (POD) of the complete dynamics. We find that the only relevant modes are the two classical normal forms associated with a Saddle-Node-Andronov bifurcation and a Shilniko

P. P. J. M. Schram, A. S. Usenko, I. P. Yakimenko

An alternative method is suggested for the description of the velocity and pressure fields in an unbounded incompressible viscous fluid induced by an arbitrary number of spheres moving and rotating in it. Within the framework of this approach, we obtain the general relations for forces and torques exerted by the fluid on the spheres. The behavior of the tran

R. Folch, E. Alvarez-Lacalle, J. Ortin, J. Casademunt

The dynamics of the interface between two immiscible fluids in a rotating Hele-Shaw cell are studied experimentally, theoretically and by phase-field simulations of the H-S equations. As the central, denser fluid is centrifuged, it forms fingering patterns with long, thin radial filaments ended by a droplet, alternating with incoming fingers of the outer flu

V. V. Ivanov, R. A. Cornelussen, H. B. van Linden van den Heuvell, R. J. C. Spreeuw

We have observed a distance-dependent absorption linewidth of cold $^{87}$Rb atoms close to a dielectric-vacuum interface. This is the first observation of modified radiative properties in vacuum near a dielectric surface. A cloud of cold atoms was created using a magneto-optical trap (MOT) and optical molasses cooling. Evanescent waves (EW) were used to obs

R. P. Malik

In view of the recent interest in a short proof of the Jacobi identity for the Poisson-brackets, we provide an alternative simple proof for the same. Our derivation is based on the validity of the Leibnitz rule in the context of dynamical evolution.

Marc Toussaint

In order to analyze and extract different structural properties of distributions, one can introduce different coordinate systems over the manifold of distributions. In Evolutionary Computation, the Walsh bases and the Building Block Bases are often used to describe populations, which simplifies the analysis of evolutionary operators applying on populations.

Margarida de Faria, Maria Joao Oliveira, Ludwig Streit

The Feynman integral for the Schroedinger propagator is constructed as a generalized function of white noise, for a linear space of potentials spanned by measures and Laplace transforms of measures, i.e., locally singular as well as rapidly growing at infinity. Remarkably, all these propagators admit a perturbation expansion.

S. H. Djah, H. Gottschalk, H. Ouerdiane

A representation of the perturbation series of a general functional measure is given in terms of generalized Feynman graphs and -rules. The graphical calculus is applied to certain functional measures of Lévy type. A graphical notion of Wick ordering is introduced and is compared with orthogonal decompositions of the Wiener-Itô-Segal type. It is also shown t

Blake Mellor

In previous work, we defined the intersection graph of a chord diagram associated with a string link (as in the theory of finite type invariants). In this paper, we look at the case when this graph is a tree, and we show that in many cases these trees determine the chord diagram (modulo the usual 1-term and 4-term relations).

R. J. Miatello, R. A. Podesta, J. P. Rossetti

We obtain a simple formula for the multiplicity of eigenvalues of the Hodge-Laplace operator, $Δ_f$, acting on sections of the full exterior bundle over an arbitrary compact flat Riemannian n-manifold M with holonomy group Z_2^k, with 0<k<n. This formula implies that any two compact flat manifolds with holonomy group Z_2^k having isospectral lattices of tran

Igor V. Dolgachev

We discuss Luigi Cremona&#39;s contribution to the early development of the theory of cubic surfaces.

D. N. Azarov, D. Tieudjo

Root-class residuality of free product of root-class residual groups is demonstrated. A sufficient condition for root-class residuality of generalized free product $G$ of groups $A$ and $B$ amalgamating subgroups $H$ and $K$ through the isomorphism $ϕ$ is derived. For the particular case when $A=B$, $H=K$ and $ϕ$ is the identity mapping, it is shown that gro

Daniel Egloff

We extend the Longstaff-Schwartz algorithm for approximately solving optimal stopping problems on high-dimensional state spaces. We reformulate the optimal stopping problem for Markov processes in discrete time as a generalized statistical learning problem. Within this setup we apply deviation inequalities for suprema of empirical processes to derive consist

Andrew Hassell, Terence Tao, Jared Wunsch

We obtain the Strichartz inequalities $$ \| u \|_{L^q_t L^r_x([0,1] \times M)} \leq C \| u(0) \|_{L^2(M)}$$ for any smooth $n$-dimensional Riemannian manifold $M$ which is asymptotically conic at infinity (with either short-range or long-range metric perturbation) and non-trapping, where $u$ is a solution to the Schrödinger equation $iu_t + {1/2} Δ_M u = 0$,

Katsuhisa Mimachi, Masaaki Yoshida

We study the twisted homology group attached to a Selberg type integral under some resonance condition, which naturally appears in the su_2-conformal field theory and the representation of the Iwahori-Hecke algebra. We determine the dimension of the space of the regularizable cycles. The dimension-formula is given in terms of the generalized hypergeometric s