Research archive
arXiv papers from June 2008
The most recent 100 records published that month. Open any paper for its original abstract, citation metadata, related research, and reading tools.
Daniel G. Figueroa, Licia Verde, Raul Jimenez
We discuss the cosmological degeneracy between the Hubble parameter H(z), the age of the universe and cosmological parameters describing simple variations from the minimal LCDM model. We show that independent determinations of the Hubble parameter H(z) such as those recently provided by Simon et al., Phys. Rev. D 71 (2005) 123001, combined with Cosmic Microw
Changyong Zhang
Link weights are the principal parameters of shortest path routing protocols, the most commonly used protocols for IP networks. The problem of optimally setting link weights for unique shortest path routing is addressed. Due to the complexity of the constraints involved, there exist challenges to formulate the problem properly, so that a solution algorithm m
R. Berman, S. Boucksom
We prove the several variable version of the classical equidistribution theorem for Fekete points of a compact subset of the complex plane, which settles a well-known conjecture in pluri-potential theory. The result is obtained as a special case of a general equidistribution theorem for Fekete points in the setting of a given holomorphic line bundle over a c
Spencer R. Klein
IceCube is a 1 km^3 neutrino detector now being built at the Amundsen-Scott South Pole Station. It consists of 4800 Digital Optical Modules (DOMs) which detect Cherenkov radiation from the charged particles produced in neutrino interactions. IceCube will observe astrophysical neutrinos with energies above about 100 GeV. IceCube will be able to separate \nu_\
T. Senthil, R. Shankar
Traditionally Fermi surfaces for problems in $d$ spatial dimensions have dimensionality $d-1$, i.e., codimension $d_c=1$ along which energy varies. Situations with $d_c >1$ arise when the gapless fermionic excitations live at isolated nodal points or lines. For $d_c > 1$ weak short range interactions are irrelevant at the non-interacting fixed point. Increas
V. M. Akulin, Yu. E. Lozzovik, I. E. Mazets, A. G. Rudavets
We consider interaction of an electron with a Bose condensate of atoms having electron affinity. Though states of the electron attached to atoms form a continuous band, tunneling through this band is strongly suppressed by quantum fluctuations of the condensate density. We adapt standard field theory methods originally developed for description of a particle
Juan M. Uson, W. D. Cotton
Radio telescopes with off-axis feeds, such as the (E)VLA, suffer from "beam squint" in which the two orthogonal circular polarizations sampled have different pointing centers on the sky. Its effects are weak near the beam center but become increasingly important towards the edge of the antenna power pattern where gains in the two polarizations at a given sky
- Cosmic ray protons in the energy range $10^{16}-10^{18.5}$ eV: stochastic gyroresonant acceleration in hypernova shocks?astro-ph
Yi-Zhong Fan
The hypernovae (HNe) associated with Gamma-ray Bursts (GRBs) may have a fairly steep energy-velocity distribution, i.e., $E(\geq \beta)\propto \beta^{-q}$ for $q<2$ and $\beta\geq \beta_o$, where $\beta$ is the velocity of the material and $\beta_o \sim 0.1$ is the velocity of the slowest ejecta of the HN explosion, both in units of the speed of light $(c)$.
M. Hajduk, A. A. Zijlstra, K. Gesicki
We study the post-AGB central star of the (bipolar) Galactic bulge planetary nebula M 2-29. We have obtained additional HST imaging and SAAO spectroscopy of the object. The star showed a pronounced, long-lasting occultation with subsequent recovery. The event lasted for almost 3 years, with a secondary minimum 9 years later. The photometric behaviour of M 2-
Gilles Halbout, Jean-Michel Oudom, Xiang Tang
Let $\Gamma$ be a finite group acting faithfully and linearly on a vector space $V$. Let $T(V)$ ($S(V)$) be the tensor (symmetric) algebra associated to $V$ which has a natural $\Gamma$ action. We study generalized quadratic relations on the tensor algebra $T(V)\rtimes \Gamma$. We prove that the quotient algebras of $T(V)\rtimes \Gamma$ by such relations sat
S. Bruce
We present a nonrelativistic wave equation for the electron in (3+1)-dimensions which includes negative-energy eigenstates. We solve this equation for three well-known instances, reobtaining the corresponding Pauli equation (but including negative-energy eigenstates) in each case.
T. Binoth, N. Kauer, P. Mertsch
A calculation of the loop-induced gluon-fusion process gg --> Z(photon)Z(photon) --> l anti-l l' anti-l' is presented, which provides an important background for Higgs boson searches in the H --> ZZ channel at the LHC. We find that the photon contribution is important for Higgs masses below the Z-pair threshold and that the gg-induced process yields a correc
Marko A. Rodriguez, Johan Bollen, Herbert Van de Sompel
In spite of its tremendous value, metadata is generally sparse and incomplete, thereby hampering the effectiveness of digital information services. Many of the existing mechanisms for the automated creation of metadata rely primarily on content analysis which can be costly and inefficient. The automatic metadata generation system proposed in this article lev
Gregory Soyez
We illustrate how the midpoint and iterative cone (with progressive removal) algorithms fail to satisfy the fundamental requirements of infrared and collinear safety, causing divergences in the perturbative expansion. We introduce SISCone and the anti-kt algorithms as respective replacements that do not have those failures without any cost at the experimenta
S. C. Lim, L. P. Teo
Two types of Gaussian processes, namely the Gaussian field with generalized Cauchy covariance (GFGCC) and the Gaussian sheet with generalized Cauchy covariance (GSGCC) are considered. Some of the basic properties and the asymptotic properties of the spectral densities of these random fields are studied. The associated self-similar random fields obtained by a
Gregory Soyez
We discuss the description of the proton structure function within the dipole factorisation framework. We parametrise the forward dipole amplitude to account for saturation as predicted by the small-x QCD evolution equations. Contrarily to previous models, the saturation scale does not decrease when taking heavy quarks into account. We show that the same dip
S. M. Gonek, A. H. Ledoan
We investigate the distribution of the zeros of partial sums of the Riemann zeta-function, sum_{n\leq X}n^{-s}, estimating the number of zeros up to height T, the number of zeros to the right of a given vertical line, and other aspects of their horizontal distribution.
- Spin Collective Modes of Two-Species Fermi Liquids: Helium-3 and Atomic Gases near the Feshbach Resonancecond-mat.other
H. P. Dahal, S. Gaudio, J. D. Feldmann, K. S. Bedell
We present theoretical findings on the spin collective modes of a two-species Fermi liquid, prepared alternatively in a polarized equilibrium or a polarized non-equilibrium state. We explore the effects on these modes of a diverging s-wave scattering length, as occurs near a Feshbach resonance in a Fermionic atomic gas. We compare these atomic gas modes with
Roberto Soria, Zdenka Kuncic
We summarize indirect empirical arguments used for estimating black hole (BH) masses in ultraluminous X-ray sources (ULXs). The interpretation of the X-ray data is still too model-dependent to provide tight constraints, but masses <~ 100 Msun seem the most likely. It is getting clearer that ULXs do not show the same evolutionary sequence between canonical sp
Roberto D. D. Costa, Oscar Cavichia, Walter J. Maciel
We report the spectrophotometric investigation of a planetary nebula sample located at the disk-bulge interface of the Milky Way. The main goal of this work was to determine the galactocentric distance where, according to the intermediate mass population, bulge and disk properties separate. In order to derive such distance, new abundances were derived for a
M. Williams, C. A. Meyer
A common goal in an experimental physics analysis is to extract information from a reaction with multi-dimensional kinematics. The preferred method for such a task is typically the unbinned maximum likelihood method. In fits using this method, the likelihood is a goodness-of-fit quantity in that it effectively discriminates between available hypotheses; howe
T. Maillart, D. Sornette, S. Spaeth, G. Von Krogh
The evolution of open source software projects in Linux distributions offers a remarkable example of a growing complex self-organizing adaptive system, exhibiting Zipf's law over four full decades. We present three tests of the usually assumed ingredients of stochastic growth models that have been previously conjectured to be at the origin of Zipf's law: (i)
Alejandro Gangui, Eduardo L. Ortiz
In an article published by Mauricio Nirenstein in 1925, a few months after the visit of Albert Einstein to Argentina, the author wrote various comments and references relative to the scientist's visit. In particular, Nirenstein mentioned a personal conversation he had with Einstein in which the sage expressed many interesting ideas on the epistemology of phy
Jorge Mondejar, Antonio Pineda
We consider deep inelastic scattering in the 't Hooft model. Being solvable, this model allows us to directly compute the moments associated with the cross section at next-to-leading order in the 1/Q^2 expansion. We perform the same computation using the operator product expansion. We find that all the terms match in both computations except for one in the h
David A. Weinberg, Nicholas J. Willis
There are 42 types of real singular points for irreducible real quintic curves and 49 types of real singular points for reducible real quintic curves. The classification of real singular points for irreducible real quintic curves is originally due to Golubina and Tai. There are 28 types of singular points for irreducible complex quintic curves and 33 types o
Alberto D. Bolatto, Adam K. Leroy, Erik Rosolowsky, Fabian Walter
We use high spatial resolution observations of CO to systematically measure the resolved size-line width, luminosity-line width, luminosity-size, and the mass-luminosity relations of Giant Molecular Clouds (GMCs) in a variety of extragalactic systems. Although the data are heterogeneous we analyze them in a consistent manner to remove the biases introduced b
Stephen R. Kane, Kaspar von Braun
The orbital parameters of extra-solar planets have a significant impact on the probability that the planet will transit the host star. This was recently demonstrated by the transit detection of HD 17156b whose favourable eccentricity and argument of periastron dramatically increased its transit likelihood. We present a study which provides a quantitative ana
David Eppstein
We prove that it is NP-complete, given a graph G and a parameter h, to determine whether G contains a complete graph K_h as a minor.
- Strongly spin-polarized current generated in Zeeman-split unconventional superconductorscond-mat.supr-con
Jacob Linder, Takehito Yokoyama, Yukio Tanaka, Asle Sudbø
We consider a thin-film normal metal/superconductor junction in the presence of an externally applied in-plane magnetic field for several symmetries of the superconducting order parameter. For p-wave superconductors, a strongly spin-polarized current emerges due to an interplay between the nodal structure of the superconducting order parameter, the existence
Jasonjot S. Kalirai, Jay Strader, Harvey B. Richer, Jay Anderson
We present the serendipitous discovery of 195 extragalactic globular clusters (GCs) in one of the deepest optical images ever obtained, a 126 orbit HST/ACS imaging study of the nearby Galactic GC NGC 6397. The distant GCs are all found surrounding a bright elliptical galaxy in the field, and are among the faintest objects detected in the image, with magnitud
Tilman Enss, Wilhelm Zwerger
We study the transition to fermion pair superfluidity in a mixture of interacting bosonic and fermionic atoms. The fermion interaction induced by the bosons and the dynamical screening of the condensate phonons due to fermions are included using the nonperturbative Hamiltonian flow equations. We determine the bosonic spectrum near the transition towards phas
Shin'ichiro Ando, Ehud Nakar, Re'em Sari
We investigate the GeV emission from gamma-ray bursts (GRBs), using the results from the Energetic Gamma Ray Experimental Telescope (EGRET), and in view of the Gamma-ray Large Area Space Telescope (GLAST). Assuming that the conventional prompt and afterglow photons originate from synchrotron radiation, we compare an accompanying inverse-Compton component wit
- Quantum oscillations in the parent magnetic phase of an iron arsenide high temperature superconductorcond-mat.supr-con
Suchitra E. Sebastian, J. Gillett, N. Harrison, P. H. C. Lau
We report quantum oscillation measurements in SrFe2As2 - which is an antiferromagnetic parent of the iron-arsenide family of superconductors - known to become superconducting under doping and the application of pressure. The magnetic field and temperature dependences of the oscillations between 20 and 55 T in the liquid helium temperature range suggest that
Jun Nakabayashi, Daisuke Yamamoto, Susumu Kurihara
Electric transport of a zigzag graphene nanoribbon through a step-like potential or a barrier potential is investigated by using the recursive Green's function method. In the case of the step-like potential, we demonstrate numerically that scattering processes obey a selection rule for the band indices when the number of zigzag chains is even; the electrons
W. V. Pogosov, V. R. Misko, H. J. Zhao, F. M. Peeters
We study theoretically the simultaneous effect of a regular and a random pinning potentials on the vortex lattice structure at filling factor of 1. This structure is determined by a competition between the square symmetry of regular pinning array, by the intervortex interaction favoring a triangular symmetry, and by the randomness trying to depin vortices fr
- Deterministic Designs with Deterministic Guarantees: Toeplitz Compressed Sensing Matrices, Sequence Designs and System Identificationcs.IT
Venkatesh Saligrama
In this paper we present a new family of discrete sequences having "random like" uniformly decaying auto-correlation properties. The new class of infinite length sequences are higher order chirps constructed using irrational numbers. Exploiting results from the theory of continued fractions and diophantine approximations, we show that the class of sequences
Kazuo Hosomichi, Ki-Myeong Lee, Sangmin Lee, Sungjay Lee
We explore further our recent generalization of the $\mathcal{N}=4$ superconformal Chern-Simons theories of Gaiotto and Witten. We find and construct explicitly theories of enhanced $\mathcal{N}=5$ or 6 supersymmetry, especially $\mathcal{N}=5$, $Sp(2M)\times O(N)$ and $\mathcal{N}=6$, $Sp(2M)\times O(2)$ theories. The $U(M)\times U(N)$ theory coincides with
Adrian Dumitrescu, Csaba D. Tóth, Guangwu Xu
A {\em Steiner star} for a set $P$ of $n$ points in $\RR^d$ connects an arbitrary center point to all points of $P$, while a {\em star} connects a point $p\in P$ to the remaining $n-1$ points of $P$. All connections are realized by straight line segments. Fekete and Meijer showed that the minimum star is at most $\sqrt{2}$ times longer than the minimum Stein
Salim Y. El Rouayheb, C. N. Georghiades, E. Soljanin, A. Sprintson
Let $A_q(n,d)$ be the maximum order (maximum number of codewords) of a $q$-ary code of length $n$ and Hamming distance at least $d$. And let $A(n,d,w)$ that of a binary code of constant weight $w$. Building on results from algebraic graph theory and Erd\H{o}s-ko-Rado like theorems in extremal combinatorics, we show how several known bounds on $A_q(n,d)$ and
Matthew Daws
It is shown that the collection of weakly almost periodic functionals on the convolution algebra of a commutative Hopf von Neumann algebra is a C$^*$-algebra. This implies that the weakly almost periodic functionals on $M(G)$, the measure algebra of a locally compact group $G$, is a C$^*$-subalgebra of $M(G)^* = C_0(G)^{**}$. The proof builds upon a factoris
Jason Behrstock, Mladen Bestvina, Matt Clay
For a fully irreducible automorphism \phi of the free group F_k we compute the asymptotics of the intersection number n \mapsto i(T,T'\phi^n) for trees T,T' in Outer space. We also obtain qualitative information about the geometry of the Guirardel core for the trees T and T'\phi^n for n large.
Mario Deile, Fritz Caspers, Tom Kroyer, Marco Oriunno
The longitudinal and transverse beam coupling impedance of the first final TOTEM Roman Pot unit has been measured in the laboratory with the wire method. For the evaluation of transverse impedance the wire position has been kept constant, and the insertions of the RP were moved asymmetrically. With the original configuration of the RP, resonances with fairly
Franck Doray, Oleg Karpenkov, Jan Schepers
Consider a graph G with n vertices. In this paper we study geometric conditions for an n-tuple of points in R^d to admit a tensegrity with underlying graph G. We introduce and investigate a natural stratification, depending on G, of the configuration space of all n-tuples in R^d. In particular we find surgeries on graphs that give relations between different
- Fermi Surface and Band Renormalization in (Sr,K)Fe$_2$As$_2$ Superconductor from Angle-Resolved Photoemission Spectroscopycond-mat.supr-con
Haiyun Liu, Wentao Zhang, Lin Zhao, Xiaowen Jia
High resolution angle-resolved photoemission measurements have been carried out on (Sr,K)Fe$_2$As$_2$ superconductor (Tc=21 K). Three hole-like Fermi surface sheets are clearly resolved for the first time around the Gamma point. The overall electronic structure shows significant difference from the band structure calculations. Qualitative agreement between t
- Study of the Detonation Phase in the Gravitationally Confined Detonation Model of Type Ia Supernovaeastro-ph
Casey A. Meakin, Ivo Seitenzahl, Dean Townsley, George C. Jordan
We study the gravitationally confined detonation (GCD) model of Type Ia supernovae through the detonation phase and into homologous expansion. In the GCD model, a detonation is triggered by the surface flow due to single point, off-center flame ignition in carbon-oxygen white dwarfs. The simulations are unique in terms of the degree to which non-idealized ph
Tatsuki Hayama
In this paper we will study the moduli spaces of log Hodge structures introduced by Kato-Usui. This moduli space is a partial compactification of a discrete quotient of a period domain. We treat the following 2 cases: (A) the case where the period domain is Hermitian symmetric, (B) the case where the Hodge structures are of the mirror quintic type. Especiall
James Bedford, David Berman
In this note we investigate quantum aspects of the newly proposed theory of multiple membranes put forward by Bagger and Lambert. In particular we analyse the possibility of a finite renormalisation of the coupling at one loop.
Teruhiko Kawano, Masahide Yamaguchi
A simple model is discussed to give rise to successful reheating in chaotic D-term inflation with a quadratic inflaton potential, introducing a trilinear coupling in the K\"ahler potential. Leptogenesis through the inflaton decay is also discussed in this model.
S. I. Veselov
Given linear diophantine equation Ax=b, rank A=m. Let d be the maximum of absolute values of the mxm minors of the matrix (A | b). It is shown that if M={x : Ax=b, x nonnegative and integer} is nonempty, then there exists x=(x1,...,xn) in M, such that xi does not exceed d (i=1,2,..,n).
Chien Yu Chen
In this paper, we consider a time dependent module field on spacetime extension without modifying commutative relation on noncommutative quantum plane. The significant idea is that $Lorentz$ symmetry is conserved in module and unmodule coordinate. We focus on the redefinition of spacetime structure without considering noncommutative bosonic gas in deforming
Vivek Mishra, P. J. Hirschfeld, Yu. S. Barash
We study a toy model for a superconductor on a bipartite lattice, where intrinsic pairing inhomogeneity is produced by two different coupling constants on the sublattices. The simplicity of the model allows for analytic solutions and tests of the consequences of atomic-scale variations in pairing interactions which have been considered recently in the cuprat
Liubin Pan, Paolo Padoan
To evaluate the effect of turbulent heating in the thermal balance of interstellar clouds, we develop an extension of the log-Poisson intermittency model to supersonic turbulence. The model depends on a parameter, d, interpreted as the dimension of the most dissipative structures. By comparing the model with the probability distribution of the turbulent diss
Alejandro Szynkman
It has been observed in B->phiK* and B^{0(+)}->rho^{0(+)}K^{*0} that the fraction of transverse decays, fT, and the fraction of longitudinal decays, fL, are roughly equal, in opposition to the naive expectation, fT/fL << 1. If one requires a single explanation of all polarization puzzles, two possibilities remain within the standard model (SM): penguin annih
W. A. Weidmann, R. Gamen, R. J. Diaz, V. S. Niemela
% context About 2500 planetary nebulae are known in our Galaxy but only 224 have central stars with reported spectral types in the Strasbourg-ESO Catalogue of Galactic Planetary Nebulae (Acker et al. 1992; Acker et al. 1996) % aims We have started an observational program aiming to increase the number of PN central stars with spectral classification. % metho
Claus M. Sorensen
In this paper, we associate Galois representations to globally generic cuspidal automorphic representations on GSp(4), over a totally real field F, which are Steinberg at some finite place. This association is compatible with the local Langlands correspondence for GSp(4) studied recently in a preprint of Gan and Takeda. As a corollary, we relate the rank of
Andre Gsponer
The electric and magnetic fields of a pole-dipole singularity attributed to a point-electron-singularity in the Maxwell field are expressed in a Colombeau algebra of generalized functions. This enables one to calculate dynamical quantities quadratic in the fields which are otherwise mathematically ill-defined: The self-energy (i.e., `mass'), the self-angular
- The effect of local dipole moments on the structure and lattice dynamics of K0.98Li0.02TaO3cond-mat.mtrl-sci
Jinsheng Wen, Guangyong Xu, C. Stock, P. M. Gehring
We present high energy x-ray (67 keV) and neutron scattering measurements on a single crystal of K$_{1-x}$Li$_x$TaO$_3$ for which the Li content ($x=0.02$) is less than $x_c = 0.022$, the critical value below which no structural phase transitions have been reported in zero field. While the crystal lattice does remain cubic down to T=10 K under both zero-fiel
L. M. Floria, C. Gracia-Lazaro, J. Gomez-Gardenes, Y. Moreno
In Evolutionary Dynamics the understanding of cooperative phenomena in natural and social systems has been the subject of intense research during decades. We focus attention here on the so-called "Lattice Reciprocity" mechanisms that enhance evolutionary survival of the cooperative phenotype in the Prisoner's Dilemma game when the population of darwinian rep
Makiko Nagashima
With U-spin symmetry, b->s and b->d penguin decays could be a subtle probe of CP violating new physics contributions. We show that, for B->PP (P stands for a pseudoscalar meson), the U-spin relation is expected to be violated for only one decay pair by assuming that new physics affects only b->s transition processes. We also very shortly discuss the polariza
- Spectral signatures of the Fulde-Ferrell-Larkin-Ovchinnikov order parameter in one-dimensional optical latticescond-mat.other
M. Reza Bakhtiari, M. J. Leskinen, P. Torma
We address an imbalanced two-component atomic Fermi gas restricted by a one-dimensional (1D) optical lattice and an external harmonic potential, within the mean-field Bogoliubov-de Gennes (BdG) formalism. We show that characteristic features of the Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) state are visible in the RF-spectra and in the momentum resolved photoe
Evgeny Andriyash, Gregory W. Moore
We study the wall-crossing behavior of the index of BPS states for D4-D2-D0 brane systems on a Calabi-Yau 3-fold at large radius and point out that not only is the ``BPS index at large radius'' chamber-dependent, but that the changes in the index can be large in the sense that they dominate single-centered black hole entropy. We discuss implications for the
Harald Dimmelmeier, Christian D. Ott, Andreas Marek, Hans-Thomas Janka
We present results from detailed general relativistic simulations of stellar core collapse to a proto-neutron star, using two different microphysical nonzero-temperature nuclear equations of state as well as an approximate description of deleptonization during the collapse phase. Investigating a wide variety of rotation rates and profiles as well as masses o
Luca de Alfaro, Rupak Majumdar, Vishwanath Raman, Mariëlle Stoelinga
We consider two-player games played over finite state spaces for an infinite number of rounds. At each state, the players simultaneously choose moves; the moves determine a successor state. It is often advantageous for players to choose probability distributions over moves, rather than single moves. Given a goal, for example, reach a target state, the questi
Amir Jafari
This is a sequel to our previous paper (joint with Furusho). It will give a more natural framework for constructing elements in the Hopf algebra of framed mixed Tate motives according to Bloch and Kriz. This framework allows us to extend our previous results to interpret all multiple zeta values (including the divergent ones) and the multiple polylogarithms
Jianqiang Zhao
We provide some examples which give evidence to the conjectures contained in my paper "Finiteness of $p$-Divisible Sets of Multiple Harmonic Sums" (math.NT/0303043). All the main theoretical results can be found in that paper.
Chul Kim, Adam K. Leibovich
The lightcone formalism including SU(3) breaking effects for the light pseudoscalar mesons is studied using soft-collinear effective theory (SCET), where the conformal symmetries needed for the expansion can be clearly implemented. The lightcone distribution amplitudes (LCDAs) are well-defined at each order in the SCET power counting, lambda. Relations betwe
Gianluca Grignani, Troels Harmark, Marta Orselli
We examine the string dual of the recently constructed $\mathcal{N}=6$ superconformal Chern-Simons theory of Aharony, Bergman, Jafferis and Maldacena (ABJM theory). We focus in particular on the $SU(2)\times SU(2)$ sector. We find a sigma-model limit in which the resulting sigma-model is two Landau-Lifshitz models added together. We consider a Penrose limit
- The Huygens principle for a uniaxial dielectric-magnetic medium with gyrotropic-like magnetoelectric propertiesphysics.optics
Tom G. Mackay, Akhlesh Lakhtakia
The dyadic Green functions for a uniaxial dielectric-magnetic medium, together with a reversible field transformation, were implemented to derive a formulation of the Huygens principle appropriate to a uniaxial dielectric-magnetic medium with gyrotropic-like magnetoelectric properties.
Andrey Beylin, Thomas L. Curtright, Evgeny Ivanov, Luca Mezincescu
A Hilbert space metric is found for the SU(2|1)-invariant `superflag' Landau models, parametrized by integer 2N' and real number M, such that the Hilbert space norm is positive definite. The spectrum of these unitary super-Landau models is determined. The M=0 case yields a unitary Landau model on the supersphere SU(2|1)/U(1|1) with U(1) charge 2N=2N'+1. For
F. Ciccarello, S. Zammito, M. Zarcone
We investigate how hot-electron fluctuations in n-type Si are affected by the presence of an intense (static) magnetic field in a Hall geometry. By using the Monte Carlo method, we find that the known Hall-effect-induced redistribution of electrons among valleys can suppress electron fluctuations with a simultaneous enhancement of the drift velocity.
Antonio D. Montero-Dorta, Francisco Prada
We present number counts, luminosity functions (LFs) and luminosity densities of galaxies obtained using the Sloan Digital Sky Survey Sixth Data Release in all SDSS photometric bands. Thanks to the SDSS DR6, galaxy statistics have increased by a factor of ~9 in the u-band and by a factor of ~4-5 in the rest of the SDSS bands with respect to the previous work
Pradeep Kiran Sarvepalli, Andreas Klappenecker
In this paper we investigate the encoding of operator quantum error correcting codes i.e. subsystem codes. We show that encoding of subsystem codes can be reduced to encoding of a related stabilizer code making it possible to use all the known results on encoding of stabilizer codes. Along the way we also show how Clifford codes can be encoded. We also show
D. G. Aronson
We consider a porous mediaum flow in which the gas is initially distributed in the exterior of an empty region (a hole) and study the final stage of the hole-filling process. Hole-filling is asymptotically described by a self-similar solution which depends on a constant determined by the initial configuration. In general, this constant must be found numerica
Eduardo I. Guendelman, Idan Shilon
We study the properties of a system consisting of an uncharged spherically symmetric two dimensional extended object which encloses a stationary point charge placed in the shell's center. We show that there can be a static and stable configuration for the neutral shell, using only the gravitational field of the charged source as a stabilizing mechanism. In p
- Matrix factorizations and intertwiners of the fundamental representations of quantum group U_q (sl_n)math.QA
Yasuyoshi Yonezawa
We want to construct a homological link invariant whose Euler characteristic is MOY polynomial as Khovanov and Rozansky constructed a categorification of HOMFLY polynomial. The present paper gives the first step to construct a categorification of MOY polynomial. For the essential colored planar diagrams with additional data which is a sequence naturally indu
S. -B. Qian, W. -P. Liao, E. Fernandez-Lajus
Up to now, most stellar-mass black holes were discovered in X-ray emitting binaries, in which the black holes are formed through a common-envelope evolu tion. Here we give evidence for the presence of a massive black hole candidate as a tertiary companion in the massive eclipsing binary V Puppis. We found that the orbital period of this short-period binary (
Marek Karliner
I discuss several recent highly accurate theoretical predictions for masses of baryons containing the b quark, as well as an effective supersymmetry between heavy quark baryons and mesons. I also suggest some possibilities for observing exotic hadrons containing heavy quarks.
Hector Freytes
An algebraic setting for the validity of Pavelka style completeness for some natural expansions of \L ukasiewicz logic by new connectives and rational constants is given. This algebraic approach is based on the fact that the standard MV-algebra on the real segment $[0, 1]$ is an injective MV-algebra. In particular the logics associated with MV-algebras with
Gleb Arutyunov, Sergey Frolov
According to the recent proposal by Aharony, Bergman, Jafferis and Maldacena the N=6 supersymmetric Chern-Simons theory in three dimensions has a 't Hooft limit whose holographic dual is described by type IIA superstings on AdS_4 x CP^3 background. We argue that the Green-Schwarz action for type IIA string theory on AdS_4 x CP^3 with kappa-symmetry partially
B. Stefanski
We present the Green-Schwarz action for Type IIA strings on $AdS_4\times CP^3$. The action is based on a $\Zop_4$ automorphism of the coset $OSp(4|6)/(SO(1,3)\times SU(3)\times U(1))$. The equations of motion admit a representation in terms of a Lax connection, showing that the system is classically integrable.
Hector Freytes
Injectives in several classes of structures associated with logic are characterized. Among the classes considered are residuated lattices, MTL-algebras, IMTL-algebras, BL-algebras, NM-algebras and bounded hoops.
- Testing Lorentz Invariance and CPT Conservation with NuMI Neutrinos in the MINOS Near Detectorhep-ex
P. Adamson
A search for a sidereal modulation in the MINOS near detector neutrino data was performed. If present, this signature could be a consequence of Lorentz and CPT violation as predicted by a class of extensions to the Standard Model. No evidence for a sidereal signal in the data set was found, implying that there is no significant change in neutrino propagation
- Optical absorption spectra and monomer interaction in polymers. Investigation of exciton coupling in DNA hairpinsphysics.chem-ph
A. L. Burin, J. A. Dickman, D. B. Uskov, C. F. F. Hebbard
We investigate the effect of exciton coupling on the optical absorption spectrum of polymer molecules under conditions of strong inhomogeneous broadening. We demonstrate that the dependence of the maximum in the rescaled absorption spectrum on the number of monomers is determined by the average monomer excitation energies and their resonant coupling and inse
- Double-Pionic Fusion of Nuclear Systems and the ABCEffect -- Aproaching a Puzzle by Exclusive and Kinematically Complete Measurementsnucl-ex
M. Bashkanov, C. Bargholtz, M. Berlowski, D. Bogoslawsky
The ABC effect - a puzzling low-mass enhancement in the $\pi\pi$ invariant mass spectrum - is well-known from inclusive measurements of two-pion production in nuclear fusion reactions. Here we report on first exclusive and kinematically complete measurements of the most basic double pionic fusion reaction $pn \to d \pi^0\pi^0$ at 1.03 and 1.35 GeV. The measu
X. Rouby
Photon interactions at the LHC result in striking final states with much lower hadronic activity in the central detectors than for pp interactions. In addition, the elastic exchange of a photon leads to a proton scattered at almost zero-degree angle. Tagging photon interactions relies on either the use of large rapidity gaps or on the detection of the scatte
- Crossover Between Organized and Disorganized States In Some Non-Equilibrium Systemscond-mat.stat-mech
D. L. Gonzalez, G. Tellez
We study numerically the crossover between organized and disorganized states of three non-equilibrium systems: the Poisson/coalesce random walk (PCRW), a one-dimensional spin system and a quasi one-dimensional lattice gas. In all cases, we describe this crossover in terms of the average spacing between particles/domain borders $< S(t) >$ and the spacing dist
Neil V. Budko
Since the 1983 definition of the speed of light in vacuum as a fundamental constant with the exact value of 299792458 m/s the question remains as to what apart from the wavefront travels at that speed. It is commonly assumed that the entire wave-packet or an impulse of the electromagnetic radiation in free space does. Here it is shown, both theoretically and
E. Tatulli, F. Malbet, F. Menard, C. Gil
51 Oph is one of the few young Be stars displaying a strong CO overtone emission at 2.3 microns in addition to the near infrared excess commonly observed in this type of stars. In this paper we first aim to locate the CO bandheads emitting region. Then, we compare its position with respect to the region emitting the near infrared continuum. We have observed
- A near-infrared interferometric survey of debris disc stars. II. CHARA/FLUOR observations of six early-type dwarfsastro-ph
O. Absil, E. Di Folco, A. Merand, J. -C. Augereau
High-precision interferometric observations of six early-type main sequence stars known to harbour cold debris discs have been obtained in the near-infrared K band with the FLUOR instrument at the CHARA Array. The measured squared visibilities are compared to the expected visibility of the stellar photospheres based on theoretical photospheric models taking
- Matrix Model For Polyakov Loops, String Field Theory In The Temporal Gauge, Winding String Condensation In Anti-de Sitter Space And Field Theory Of D-braneshep-th
Kazuyuki Furuuchi
Closed string field theory is constructed by stochastically quantizing a matrix model for Polyakov loops that describes phases of a large N gauge theory at finite temperature. Coherent states in this string field theory describes winding string condensation which has been expected to cause a topology change from thermal AdS geometry to AdS-Schwarzschild blac
Toshifumi Itakura
In this study, we examine decoherence of qubits system coupled independently by using influence functional. We especially concentrated on the effect of qubit flip process. We examine the zero-dimensional qubit and one-dimensional qubits system coupled with multi-band one-dimensional system. The qubit flip process leads to oscillation and self-excitation. We
Bruno Galvan
A new formulation of quantum mechanics is proposed based on a new principle that can be considered a generalization of the Born rule. The principle is composed of a mathematical expression and an associated interpretation, and establishes a correlation between the positions of a particle at two different times. Under reasonable conditions for the wave functi
Peng Gao
The Density Conjecture of Katz and Sarnak associates a classical compact group to each reasonable family of $L$-functions. Under the assumption of the Generalized Riemann Hypothesis, Rubinstein computed the $n$-level density of low-lying zeros for the family of quadratic Dirichlet $L$-functions in the case that the Fourier transform $\hat{f}(u)$ of any test
Xiao-Hui Bao, Yong Qian, Jian Yang, Han Zhang
We report an experimental realization of a narrow-band polarization-entangled photon source with a linewidth of 9.6 MHz through cavity-enhanced spontaneous parametric down-conversion. This linewidth is comparable to the typical linewidth of atomic ensemble based quantum memories. Single-mode output is realized by setting a reasonable cavity length difference
- Site Dilution in the Half-Filled One-Band Hubbard Model: Ring Exchange, Charge Fluctuations and Application to La2Cu_{1-x}(Mg/Zn)_xO4cond-mat.stat-mech
J. -Y. P. Delannoy, A. G. Del Maestro, M. J. P. Gingras, P. C. W. Holdsworth
We study the ground state quantum spin fluctuations around the N\'eel ordered state for the one-band ($t,U$) Hubbard model on a site-diluted square lattice. An effective spin Hamiltonian, $H_{\rm s}^{(4)}$, is generated using the canonical transformation method, expanding to order $t(t/U)^3$. $H_{\rm s}^{(4)}$ contains four-spin ring exchange terms as well a
C. A. Aidala
A unique new facility, capable of colliding beams of electrons with a wide range of nuclei as well as polarized protons and light ions, has been proposed to study the role of gluons in matter and perform precision mapping of the structure of nucleons and nuclei. The physics prospects of the proposed Electron-Ion Collider (EIC) are discussed.
G. Watt, A. D. Martin, W. J. Stirling, R. S. Thorne
We discuss selected topics in the forthcoming MSTW 2008 determination of parton distributions by global analysis. The tolerance parameter controlling the uncertainties on the parton distributions is now determined by a new dynamic procedure for each eigenvector of the covariance matrix. New data sets fitted include Tevatron Run II data on inclusive jet produ
- Ultrafast manipulation of electron spins in a double quantum dot device: A real-time viewcond-mat.mes-hall
Gianluca Stefanucci, Enrico Perfetto, Michele Cini
We consider a double quantum dot system with two embedded and non-aligned spin impurities to manipulate the magnitude and polarization of the electron spin density. The device is attached to semi-infinite one-dimensional leads which are treated exactly. We provide a real-time description of the electron spin dynamics when a sequence of ultrafast voltage puls
- Diffusional Nucleation of Nanocrystals and Their Self-Assembly into Uniform Colloidscond-mat.stat-mech
Vladimir Privman
We review theoretical explanation of mechanisms of control of uniformity in growth of nanosize particles and colloids. The nanoparticles are synthesized as nanocrystals, by burst nucleation from solution. The colloids are self-assembled by aggregation of these nanocrystals. The two kinetic processes are coupled, and both are driven by diffusional transport.
S. J. van Enk
I consider two identical quantum particles in two boxes. We can split each box, and thereby the wavefunction of each particle, into two parts. When two half boxes are interchanged and combined with the other halves, where do the two particles end up? I solve this problem for two identical bosons and for two identical fermions. The solution can be used to def