January 2003 arXiv papers — page 20
Showing 1,901–2,000 of 2,887 papers
John P. Wisniewski, Nancy D. Morrison, Karen S. Bjorkman, Anatoly S. Miroshnichenko
The spectroscopic and spectropolarimetric variability of the peculiar variable V838 Monocerotis during the brighter phases of its multiple outbursts in 2002 is presented. Significant line profile variability of H$α$ and Si II 6347.10Å& 6371.36Åoccurred in spectra obtained between 2002 February 5 and 2002 March 14, and a unique secondary absorption component
Takuji Tsujimoto, Toshikazu Shigeyama
The unique elemental abundance pattern of the carbon-rich stars CS29498-043 and CS22949-037 is characterized by a large excess of magnesium and silicon in comparison with iron. This excess is investigated in the context of a supernova-induced star formation scenario, and it is concluded that these stars were born from the matter swept up by supernova remnant
X-ray Studies of Two Neutron Stars in 47 Tucanae: Toward Constraints on the Equation of State
astro-phC. O. Heinke, J. E. Grindlay, D. A. Lloyd, P. D. Edmonds
We report spectral and variability analysis of two quiescent low mass X-ray binaries (X5 and X7, previously detected with the ROSAT HRI) in a Chandra ACIS-I observation of the globular cluster 47 Tuc. X5 demonstrates sharp eclipses with an 8.666+-0.01 hr period, as well as dips showing an increased N_H column. The thermal spectra of X5 and X7 are well-modele
H. V. Fagundes, E. Gausmann
The cosmic crystallography method of Lehoucq et al. [1] produces sharp peaks in the distribution of distances between the images of cosmic sources. But the method cannot be applied to universes with compact spatial sections of negative curvature. We apply to these a second order crystallographic effect, as evidenced by statistical parameters.
Jesus M. Mira, William A. Ponce, Diego A. Restrepo, Luis A. Sanchez
The Higgs potential and the mass spectrum of the N=1 supersymmetric extension of a recently proposed one-family model based on the local gauge group $SU(3)_c \otimes SU(3)_L \otimes U(1)_X$, which is a subgroup of the electroweak-strong unification group $E_6$, is analyzed. In this model the slepton multiplets play the role of the Higgs scalars and no Higgsi
Donu Arapura
Our goal is to prove that the Leray spectral sequence associated to a map of algebraic varieties is motivic in the following sense: If the singular cohomology groups of the category of quasiprojective varieties defined over a subfield of C can be canonically endowed with some additional structure, such as its mixed Hodge structure or its motive (in Nori'
Prashanth Jaikumar, Anupam Mazumdar
We propose that the origin of ultra-high energy cosmic rays beyond the GZK cutoff and the origin of small cosmological constant can both be explained by vacuum tunneling effects in a theory with degenerate vacua and fermionic doublets. By considering the possibility of tunneling from a particular winding number state, accompanied by violation of some global
Costas G. Strouthos
We discuss the critical properties of the three-dimensional NJL model at nonzero temperature. We show that the Z(2)-symmetric model undergoes a second order phase transition with 2d Ising exponents and its critical region is suppressed by a factor 1/N^{-0.5}. We also provide numerical evidence that the U(1)-symmetric model undergoes a BKT transition in accor
Sung Ho Wang
We prove a relative isoperimetric inequalities for Lagrangian half disks in $\mathbb{C}^2$ with respect to a Lagrangian plane, or a complex plane, or a union of any two of Lagrangian or complex planes that intersect transversally at the origin.
Margarida Mendes Lopes, Rita Pardini
Let $S$ be a minimal surface of general type with $p_g=0$ and $K^2=6$, such that its bicanonical map $\fie\colon S\to\pp^6$ is not birational. The map $\fie$ is a morphism of degree $\le 4$ onto a surface. The case of $°\fie=4$ is completely characterized in [Topology, {\bf 40} (5) (2001), 977--991] and the present paper completes the classification of these
C. M. Newman, D. L. Stein
We study chaotic size dependence of the low temperature correlations in the SK spin glass. We prove that as temperature scales to zero with volume, for any typical coupling realization, the correlations cycle through every spin configuration in every fixed observation window. This cannot happen in short-ranged models as there it would mean that every spin co
Mohsen Alishahiha, Ori J. Ganor
We study partially supersymmetric plane-wave like deformations of string theories and M-theory on brane backgrounds. These deformations are dual to nonlocal field theories. We calculate various expectation values of configurations of closed as well as open Wilson loops and Wilson surfaces in those theories. We also discuss the manifestation of the nonlocalit
J. S. Alcaniz, J. A. S. Lima, J. V. Cunha
The existence of old high-redshift objects provides an important tool for constraining the expanding age of the Universe and the formation epoch of the first objects. In a recent paper, Hasinger {\it et al.} (2002) reported the discovery of the quasar APM 08279+5255 at redshift $z=3.91$ with an extremely high iron abundance, and estimated age of 2 - 3Gyr. By
R. P. Fender
It is shown that the two-sided jet proper motions observed from the galactic microquasars GRS 1915+105 and GRO J1655-40 in practice only allow us to place lower limits on the Lorentz factors of the outflows. As a consequence, it is not possible to rule out the possibility that jets from X-ray binaries are just as relativistic as those from active galactic nu
Simulations of Galaxy Formation in a Lambda CDM Universe III: The Dissipative Formation of an Elliptical Galaxy
astro-phAndres Meza, Julio F. Navarro, Matthias Steinmetz, Vincent R. Eke
We examine in detail the dynamical structure of an elliptical galaxy simulated in the Lambda CDM scenario. The morphology of the galaxy evolves dramatically over time in response to the mode and timing of mass accretion; smooth deposition of cooled gas leads to the formation of centrifugally supported disks, whilst major mergers disperse stellar disks into s
P. Tumarkin
In this paper, we classify all the hyperbolic non-compact Coxeter polytopes of finite volume combinatorial type of which is either a pyramid over a product of two simplices or a product of two simplices of dimension greater than one. Combined with results of Kaplinskaja (1974) and Esselmann (1996) this completes the classification of hyperbolic Coxeter n-pol
Wolfgang Dobler, Peter Frick, Rodion Stepanov
The kinematic dynamo problem is investigated for the flow of a conducting fluid in a cylindrical, periodic tube with conducting walls. The methods used are an eigenvalue analysis of the steady regime, and the three-dimensional solution of the time-dependent induction equation. The configuration and parameters considered here are close to those of a dynamo ex
Irina Mocioiu, Yasushi Nara, Ina Sarcevic
In models with several large extra dimensions and fundamental Planck scale of the order of 1 TeV, black holes can be produced in large numbers at LHC energies. We compute the charged hadron spectra obtained from the decay of black holes created in p-p and Pb+Pb collisions at LHC. We show that hadrons from black hole decay dominate at transverse momenta p_T>3
Time correlations and 1/f behavior in backscattering radar reflectivity measurements from cirrus cloud ice fluctuations
cond-mat.stat-mechK. Ivanova, T. P. Ackerman, E. E. Clothiaux, P. Ch. Ivanov
The state of the atmosphere is governed by the classical laws of fluid motion and exhibits correlations in various spatial and temporal scales. These correlations are crucial to understand the short and long term trends in climate. Cirrus clouds are important ingredients of the atmospheric boundary layer. To improve future parameterization of cirrus clouds i
Victor Galitski, S. Das Sarma
We study the effect of superconducting fluctuations on the upper critical field of a disordered superconducting film at low temperatures. The first order fluctuation correction is found explicitly. In the framework of the perturbative analysis, superconducting fluctuations are shown to shift the upper critical field line toward lower fields and do not lead t
R. Raussendorf, D. E. Browne, H. J. Briegel
We give a detailed account of the one-way quantum computer, a scheme of quantum computation that consists entirely of one-qubit measurements on a particular class of entangled states, the cluster states. We prove its universality, describe why its underlying computational model is different from the network model of quantum computation and relate quantum alg
Tailorable acceptor ${\rm C}_{60-n}{\rm B}_{n}$ and donor ${\rm C}_{60-m}{\rm N}_{m}$ pairs for molecular electronics
cond-mat.mtrl-sciRui-Hua Xie, Garnett W. Bryant, Jijun Zhao, Vedene H. Smith
Our first-principles calculations demonstrate that ${\rm C}_{60-n}{\rm B}_{n}$ and ${\rm C}_{60-m}{\rm N}_{m}$ molecules can be engineered as the acceptors and donors, respectively, which are needed for molecular electronics, by properly controlling the number $n$ and $m$ of the substitutional dopants in ${\rm C}_{60}$. As an example, we show that acceptor $
David Campo, Renaud Parentani
In homogeneous universes the propagation of quantum fields gives rise to pair creation of quanta with opposite momenta. When computing expectation values of operators, the correlations between these quanta are averaged out and no space-time structure is obtained. In this article, by an appropriate use of wave packets, we reveal the space-time structure of th
Chandra X-ray analysis of the massive high-redshift galaxy clusters ClJ1113.1-2615 and ClJ0152.7-1357
astro-phB. J. Maughan, L. R. Jones, H. Ebeling, E. Perlman
We present an analysis of Chandra observations of two high-redshift clusters of galaxies, ClJ1113.1-2615 at z=0.725 and ClJ0152.7-1357 at z=0.833. We find ClJ1113 to be relaxed with kT=4.3^{+0.5}_{-0.4}keV and a mass (within the virial radius) of 4.3^{+0.8}_{-0.7}*10^{14}Msol. ClJ0152, by contrast, is resolved into a northern and southern subcluster, each ma
R. Mainini, L. P. L. Colombo, S. A. Bonometto
High sensitivity polarization measures, on wide angular scales, together with data on anisotropy, can be used to fix DE parameters. In this paper, first of all, we aim to determine the sensitivity needed to provide significant limits. Our analysis puts in evidence that there is a class of DE models that polarization measures can possibly exclude soon. This c
Addition Energies of Fullerenes and Nanotubes as Quantum Dots: The Role of Symmetry
cond-mat.mtrl-sciSan-Huang Ke, Harold U. Baranger, Weitao Yang
Using density-functional theory calculations, we investigate the addition energy (AE) of quantum dots formed of fullerenes or closed single-wall carbon nanotubes. We focus on the connection between symmetry and oscillations in the AE spectrum. In the highly symmetric fullerenes the oscillation period is large because of the large level degeneracy and Hund
B. L. G. Bakker, A. I. Veselov, M. A. Zubkov
We found an additional symmetry hidden in the fermion and Higgs sectors of the Standard Model. It is connected to the centers of the SU(3) and SU(2) subgroups of the gauge group. A lattice regularization of the whole Standard Model is constructed that possesses this symmetry.
Chanju Kim, Hang Bae Kim, Yoonbai Kim, O-Kab Kwon
We study Born-Infeld type effective action for unstable D3-brane system including a tachyon and an Abelian gauge field, and find the rolling tachyon with constant electric and magnetic fields as the most general homogeneous solution. Tachyonic vacua are characterized by magnitudes of the electric and magnetic fields and the angle between them. Analysis of sm
Kim Bostroem
A quantum mechanical theory is proposed which abandons an external parameter ``time'' in favor of a self-adjoint operator on a Hilbert space whose elements represent measurement events rather than system states. The standard quantum mechanical description is obtained in the idealized case of measurements of infinitely short duration. A theory of pert
Yuan-Ben Dai, Chao-Shang Huang, Jian-Tao Li, Wen-Jun Li
We have calculated the Wilson coefficients $C_{10}, C_{Q_i}$ (i=1,2) in the $\bar{MS}$ renormalization scheme in the model III 2HDM. Using the obtained Wilson coefficients, we have analyzed the CP violation in decays $B^0_q\to l^+l^-$ (q=d,s) in the model. The CP asymmetry, $A_{CP}$, depends on the parameters of models and $A_{CP}$ in $B_d\to l^+l^-$ can be
Renormalization Group Analysis of the 2000-2002 anti-bubble in the US S&P 500 index: Explanation of the hierarchy of 5 crashes and Prediction
physics.soc-phW. -X. Zhou, D. Sornette
We propose a straightforward extension of our previously proposed log-periodic power law model of the ``anti-bubble'' regime of the USA market since the summer of 2000, in terms of the renormalization group framework to model critical points. Using a previous work by Gluzman and Sornette (2002) on the classification of the class of Weierstrass-like f
Ezio Vasselli
We introduce the notion of fibred action of a group bundle on a C(X)-algebra. By using such a notion, a characterization in terms of induced C*-bundles is given for C*-dynamical systems such that the relative commutant of the fixed-point algebra is minimal (i.e., it is generated by the centre of the given C*-algebra and the centre of the fixed-point algebra)
E. G. Berezhko, G. Puehlhofer, H. J. Voelk
The nonlinear kinetic model of cosmic ray (CR) acceleration in supernova remnants (SNRs) is used to describe the relevant properties of Cassiopeia A (Cas A). In order to reproduce the SNR's observed size, expansion rate and thermal X-ray emission we employ a piecewise homogeneous model for the progenitor's circumstellar medium developed by Borkowski
L. Dong, G. Q. Gu, K. W. Yu
We have studied the effective response of composites of spherical particles each having a dielectric profile which varies along the radius of the particles. We developed a first-principles approach to compute the dipole moment of the individual spherical particle and hence the effective dielectric response of a dilute suspension. The approach has been applie
Taejun Lee, Chaiho Rim
(R-channel) TBA is elaborated to find the effective central charge dependence on the boundary parameters for the massless boundary sine-Gordon model with the coupling constant $(8π) /β^2 = 1+ λ$ with $λ$ a positive integer. Numerical analysis of the massless boundary TBA demonstrates that at an appropriate boundary parameter range (cusp point) there exists a
What can the quantum liquid say on the brane black hole, the entropy of extremal black hole and the vacuum energy?
gr-qcG. E. Volovik
Using quantum liquids one can simulate the behavior of the quantum vacuum in the presence of the event horizon. The condensed matter analogs demonstrate that in most cases the quantum vacuum resists to formation of the horizon, and even if the horizon is formed different types of the vacuum instability develop, which are faster than the process of Hawking ra
Wave Packet Spreading: Temperature and Squeezing Effects with Applications to Quantum Measurement and Decoherence
quant-phG. W. Ford, R. F. O'Connell
A localized free particle is represented by a wave packet and its motion is discussed in most quantum mechanics textbooks. Implicit in these discussions is the assumption of zero temperature. We discuss how the effects of finite temperature and squeezing can be incorporated in an elementary manner. The results show how the introduction of simple tools and id
Kurt Jacobs
When one performs a continuous measurement, whether on a classical or quantum system, the measurement provides a certain average rate at which one becomes certain about the state of the system. For a quantum system this is an average rate at which the system is projected onto a pure state. We show that for a standard kind of continuous measurement, for a qub
G. W. Ford, J. T. Lewis, R. F. O'Connell
Distribution functions defined in accord with the quantum theory of measurement are combined with results obtained from the quantum Langevin equation to discuss decoherence in quantum Brownian motion. Closed form expressions for wave packet spreading and the attenuation of coherence of a pair of wave packets are obtained. The results are exact within the con
G. W. Ford, R. F. O'Connell
The prototypical Schrödinger cat state, i.e., an initial state corresponding to two widely separated Gaussian wave packets, is considered. The decoherence time is calculated solely within the framework of elementary quantum mechanics and equilibrium statistical mechanics. This is at variance with common lore that irreversible coupling to a dissipative enviro
G. W. Ford, R. F. O'Connell
The Hu-Paz-Zhang equation is a master equation for an oscillator coupled to a linear passive bath. It is exact within the assumption that the oscillator and bath are initially uncoupled . Here an exact general solution is obtained in the form of an expression for the Wigner function at time t in terms of the initial Wigner function. The result is applied to
Andrei Khrennikov
By analysing probabilistic foundations of quantum theory we understood that the so called quantum calculus of probabilities (including Born's rule) is not the main distinguishing feature of "quantum". This calculus is just a special variant of a contextual probabilistic calculus. In particular, we analysed the EPR-Bohm-Bell approach by using cont
M. Murakami, G. W. Ford, R. F. O'Connell
Much of the discussion of decoherence has been in terms of a particle moving in one dimension that is placed in an initial superposition state (a Schrödinger "cat" state) corresponding to two widely separated wave packets. Decoherence refers to the destruction of the interference term in the quantum probability function. Here, we stress that a quanti
Qing-yu Cai
Based on an EPR pair of qubits and allowing asymptotically secure key distribution, a secure communication protocol is presented. Bob sends either of the EPR pair qubits to Alice. Alice receives the travel qubit. Then she can encode classical information by local unitary operations on this travel qubit. Alice send the qubit back to Bob. Bob can get Alice'
Y. Ben-Aryeh
A theoretical analysis of Pancharatnam and Berry phases is made for biphoton three-level systems, which are produced via frequency degenerate co-linear spontaneous parametric down conversion (SPDC). The general theory of Pancharatnam phases is discussed with a special emphasis on geodesic 'curves'in Hilbert space. Explicit expressions for Pancharatna
George Svetlichny
A physical theory of experiments carried out in a space-time region can accommodate a detector localized in another space-like separated region, in three, not necessarily exclusive, ways: 1) the detector formally collapses physical states across space-like separations, 2) the detector enables superluminal signals, and 3) the theory becomes logically inconsis
Weiren Chou
This lecture is an introduction to the design of a spallation neutron source and other high intensity proton sources. It discusses two different approaches: linac-based and synchrotron-based. The requirements and design concepts of each approach are presented. The advantages and disadvantages are compared. A brief review of existing machines and those under
D. Asthagiri, Lawrence R. Pratt
Be$^{2+}$(aq) hydrolysis can to lead to the formation of multi-beryllium clusters, but the thermodynamics of this process has not been resolved theoretically. We study the hydration state of an isolated Be$^{2+}$ ion using both the quasi-chemical theory of solutions and ab initio molecular dynamics. These studies confirm that Be$^{2+}$(aq) is tetra-hydrated.
R. Delbourgo, Brian G. Kenny
We describe the morphology of the universal function for the critical (cubic) circle map at the golden mean, paying particular attention to the birth of inflection points and their reproduction. In this way one can fully understand its intricacies.
O. E. Aiello, M. A. A. da Silva
In this work we introduce a new approach to Dynamical Monte Carlo methods to simulate markovian processes. We apply this approach to formulate and study an epidemic generalized SIRS model. The results are in excellent agreement with the fourth order Runge-Kutta method in a region of deterministic solution. Introducing local stochastic interactions, the Runge
Al. H. Raduta, Ad. R. Raduta
The effects of (in)homogeneity and size on the phase diagram of Lennard-Jones fluids are investigated. It is shown that standard multifragmentation scenarios (finite equilibrated systems with conserved center of mass position and momentum) are implying a strong radial inhomogeneity of the system strongly affecting the phase diagram. The homogeneity constrain
The $A_y$-Problem in Refined Resonating Group Model calculations for ($p-^3{\rm He}$) Scattering
nucl-thC. Reiss, H. M. Hofmann
We report on a microscopic Refined Resonating Group Model (RRGM) calculation of scattering of $p$ off ${}^3{\rm He}$ employing the Argonne-$v_{14}$ and the Bonn nucleon-nucleon potentials without three-nucleon forces at low energies up to 30 MeV. The calculated phase-shifts verify the well-known proton analyzing power $A_y$-problem. We demonstrate that with
Trap Activation Energy and Transport Parameters of HgI$_2$ Crystals for Bubble-Plasma Diagnostics
nucl-exM. B. Miller, V. F. Kushniruk, A. V. Sermyagin
In recent data on neutron induced acoustic cavitation in deuterium--containing liquids obtained by neutron measurements it was shown that very high temperatures could arise in some special cases. To study temperature of so--called bubble plasma it is desirable to have micro--detectors of X-rays, which can be prepared on the basis of room--temperature semicon
Kathleen Cotrill-Shepherd, Mark NAber
This work further develops the properties of fractional differential forms. In particular, finite dimensional subspaces of fractional form spaces are considered. An inner product, Hodge dual, and covariant derivative are defined. Coordinate transformation rules for integral order forms are also computed. Matrix order fractional calculus is used to define mat
R. Alicki, M. Fannes, B. Haegeman, D. Vanpeteghem
This paper consists in two parts. First we set up a general scheme of local traps in an homogeneous deterministic quantum system. The current of particles caught by the trap is linked to the dynamical behaviour of the trap states. In this way, transport properties in an homogeneous system are related to spectral properties of a coherent dynamics. Next we app
Eugene Lerman
We define contact fiber bundles and investigate conditions for the existence of contact structures on the total space of such a bundle. The results are analogous to minimal coupling in symplectic geometry. The two applications are construction of K-contact manifolds generalizing Yamazaki's fiber join construction and a cross-section theorem for contact m
Thomas Strohmer, Robert Heath
For a given class ${\cal F}$ of uniform frames of fixed redundancy we define a Grassmannian frame as one that minimizes the maximal correlation $|< f_k,f_l >|$ among all frames $\{f_k\}_{k \in {\cal I}} \in {\cal F}$. We first analyze finite-dimensional Grassmannian frames. Using links to packings in Grassmannian spaces and antipodal spherical codes we deriv
A. J. E. M. Janssen, Thomas Strohmer
We show that $(g_2,a,b)$ is a Gabor frame when $a>0, b>0, ab<1$ and $g_2(t)=({1/2}πγ)^{1/2} (\cosh πγt)^{-1}$ is a hyperbolic secant with scaling parameter $γ>0$. This is accomplished by expressing the Zak transform of $g_2$ in terms of the Zak transform of the Gaussian $g_1(t)=(2γ)^{1/4} \exp (-πγt^2)$, together with an appropriate use of the Ron-Shen crite
Santiago Morales
The main goal of this paper is to show a counterexample to the following conjecture: {\bf Conjecture} [Meeks, Sullivan]: If $f:M\to \mathbb{R}^3$ is a complete proper minimal immersion where $M$ is a Riemannian surface without boundary and with finite genus, then $M$ is parabolic. We have proved: {\bf Theorem:} There exists $χ: D\longrightarrow \mathbb{R}^3$
M. I. Neiman-zade, A. A. Shkalikov
We study the operator $L=-Δ+q$ on a bounded domain $Ω\subset\mathbb R^n$, where $q(x)$ is a distributional potential. We find sufficient conditions for $q(x)$ which guarantee that $L$ is well--defined with Dirichlet and generalized Neumann boundary conditions. The asymptotics of the eigenvalues and the basis properties of the eigen- and associated functions
M. I. Neiman-zade, A. A. Shkalikov
We study operators of the form $$ L=\sum_{|α|,|β|\le n} D^αc_{α,β} D^β, x\in\mathbb R^n $$ provided that the coefficients of the main symbol corresponding to the indices $|α|=|β|=m$ are continuous while the other ones are distributions. Assuming that the main symbol defines the strongly elliptic operator we find sufficient conditions for the coefficients $c_
Matthias Kuenzer
We generalize certain parts of the theory of group rings to the twisted case. Let G be a finite group acting (possibly trivially) on a field L of characteristic coprime to the order of the kernel of this operation. Let K in L be the fixed field of this operation, let S be a discrete valuation ring with field of fractions K, maximal ideal generated by pi and
Tomasz Brzezinski, Ludwik Dabrowski, Bartosz Zielinski
Noncommutative geometry of quantised contact spheres introduced by Omori, Maeda, Miyazaki and Yoshioka is studied. In particular it is proven that these spheres form a noncommutative Hopf fibration in the sense of Hopf-Galois extensions. The monopole (strong) connection is constructed, and projectors describing projective modules of all monopole charges are
M. I. Neiman-zade, A. A. Shkalikov
A function $q(x)$ is said to be a multiplier from the Sobolev space $H^\al_p(R^n)$ into $H^{-\al}_p(R^n)$ if the operator $Lf(x)=q(x)f(x)$ is a bounded operator from the first space into the second one. Let $M^\al_p$ the the space of such multipliers. In this paper we give the description of the spaces $M^\al_p$ provided the condition $\al>min(n/p,n/p')$
Andrew Ranicki
Novikov initiated the study of the algebraic properties of quadratic forms over polynomial extensions by a far-reaching analogue of the Pontrjagin-Thom transversality construction of a Seifert surface of a knot and the infinite cyclic cover of the knot exterior. In this paper the analogy is applied to explain the relationship between the Seifert forms over a
Ely Kerman, Francois Lalonde
In this paper we consider the length minimizing properties of Hamiltonian paths generated by quasi-autonomous Hamiltonians on symplectically aspherical manifolds. Motivated by the work of L. Polterovich and M. Schwarz, we study the role of the fixed global extrema in the Floer complex of the generating Hamiltonian. Our main result determines a natural condit
Yakov Sinai
Take an odd number x >0. Then 3x+1 is even and one can find an integer k> 0 so that y= 3x+1/2^k is again odd. We get in this way the mapping T, Tx=y. The paper contains two theorems describing statistical properties of T. The first describes statistical properties of trajectories for large x. The second gives some information about the probability distributi
Robert Friedman, John W. Morgan
Given a minuscule representation of a simple Lie algebra, we find an algebraic model for the action of a regular element and show that these models can be glued together over the adjoint quotient, viewed as the set of all regular conjugacy classes of the Lie algebra. There are partial results in the case of a quasiminuscule representation, and a conjecture i
Suphot Musiri, George Siopsis
We develop a perturbative approach to the solution of the scalar wave equation for a large AdS black hole. In three dimensions, our method coincides with the known exact solution. We discuss the five-dimensional case in detail and apply our procedure to the Heun equation. We calculate the quasi-normal modes analytically and obtain good agreement with numeric
Nadav Drukker
We study a family of kinetic operators in string field theory describing the theory around the closed string vacuum. Those operators are based on the analytical classical solutions of Takahashi and Tanimoto and are analogous to the pure ghost action usually referred to as "vacuum string field theory," but are much more general, and less singular than the pur
A. Levin, M. Olshanetsky
Starting with a Lie algebroid ${\cal A}$ over a space $M$ we lift its action to the canonical transformations on the affine bundle ${\cal R}$ over the cotangent bundle $T^*M$. Such lifts are classified by the first cohomology $H^1({\cal A})$. The resulting object is a Hamiltonian algebroid ${\cal A}^H$ over ${\cal R}$ with the anchor map from $\G({\cal A}^H)
E. V. Orlov, A. I. Sokolov
The renormalization-group functions of the two-dimensional n-vector λϕ^4 model are calculated in the five-loop approximation. Perturbative series for the β-function and critical exponents are resummed by the Pade-Borel-Leroy techniques. An account for the five-loop term shifts the Wilson fixed point location only briefly, leaving it outside the segment forme
Sergei V. Ketov
The non-perturbative (D-instanton corrected) low-energy effective action of the universal hypermultiplet in the type-IIA string theory compactified on a Calabi-Yau threefold is calculated in 4d, N=2 supergravity. The action is given by the quaternionic non-linear sigma-model whose metric is governed by the Eisenstein series E_{3/2}. The U(1)xU(1) isometry an
Y. S. Myung
We introduce the relation between the holographic entropy bounds and the inflationary universe. First the holographic entropy bounds for radiation-dominated universe, radiation-dominated universe with a positive cosmological constant are introduced. For an exact de Sitter phase, we use the maximal entropy bound. We classify the inflation based on the quasi-d
A. Gorsky
We briefly review the recent progress concerning the application of the hidden integrability to the derivation of the stringy/brane picture for the high energy QCD.
D. Blaschke, H. Grigorian, D. N. Aguilera, S. Yasui
The equation of state for quark matter is derived for a nonlocal, chiral quark model within the mean field approximation. We investigate the effects of a variation of the form factors of the interaction on the phase diagram of quark matter under the condition of beta-equilibrium and charge neutrality. Special emphasis is on the occurrence of a diquark conden
Frank Daniel Steffen
We develop a loop-loop correlation model for a unified description of static color dipole potentials, confining QCD strings, and hadronic high-energy reactions with special emphasis on saturation effects manifesting S-matrix unitarity at ultra-high energies. The model combines perturbative gluon exchange with the non-perturbative stochastic vacuum model whic
C. K. Bowdery
There could be a Higgs boson with a mass less than 100 GeV/c2 in the LEP data if its decay width and modes are not dominated by b quarks. At present, the quantum interference between signal and background processes has not been considered in flavour independent searches but when it is, the long-sought particle may appear.
J. R. Andersen, W. J. Stirling
We study the associated jet multiplicity arising from t-channel BFKL gluon evolution in forward dijet production at hadron colliders. Previous results have shown that the effect of conserving overall energy and momentum is to introduce a pdf suppression that completely compensates the predicted exponential BFKL rise with rapidity difference between the leadi
Lindhard Factors and Concentrations of Primary Defects in Semiconductor Materials for uses in HEP
hep-phI. Lazanu, S. Lazanu
This report is a compilation of authors' calculations of the Lindhard factors, and of the concentration of primary radiation defects per unit particle fluence in different materials for HEP uses.
Margarete Herz
We present constraints on products of two leptoquark (LQ) coupling constants. The bounds are obtained from meson decays, in particular leptonic π, K, D, D_s, B, B_s decays. Furthermore semileptonic meson decays and mixing in neutral meson systems are discussed. We use the Buchmueller-Rueckl-Wyler-model for scalar and vector LQs. Bounds on R-parity violation
Variation of the relative yield of charged and neutral B mesons across the Upsilon(4S) resonance
hep-phM. B. Voloshin
It is shown that the ratio of the production rates of the pairs (B+ B-) and (B0 anti-B0) should experience a substantial and rapid variation with energy within the width of the Upsilon(4S) resonance, crossing the value of one near the center of the resonance. This behavior is due to an interference of the rapidly changing with energy Breit-Wigner phase with
M. Dey, V. L. Eletsky, B. L. Ioffe
It is shown, that the correlators of vector and axial-vector currents at finite temperature T in order T^2 reduce to mixing of vacuum VV and AA correlators with universal mixing coefficient given by the parameter ε= T^2/6 F^2_π, unlike the claim in the recent paper by Mallik and Sarkar [1].
H. Kröger, X. Q. Luo, K. J. M. Moriarty
In order to solve quantum field theory in a non-perturbative way, Lagrangian lattice simulations have been very successful. Here we discuss a recently proposed alternative Hamiltonian lattice formulation - the Monte Carlo Hamiltonian. In order to show its working in the case of the scalar $Φ^{4}_{1+1}$ model, we have computed thermodynamic functions like fre
T. Kamon
We summarize a discovery potential for supersymmetric particles at the \ppbar collider of Tevatron with center-of-mass energy \sqrt{s} = 2 TeV and integrated luminosity $\intlum$ = 15-30 \invfb. Any direct search is kinematically limited to below 450 \mgev. We, however, have a unique opportunity to test various supersymmetric scenarios by a measurement of th
The OPAL collaboration, G. Abbiendi
The decay chain b -> Bbar -> D^{**0} l nu X, D^{**0} -> D^{*+} pi^-, D^{*+} -> D^0 pi^+, D^0 ->(Kpi or K3pi) is identified in a sample of 3.9 million hadronic Z decays collected with the OPAL detector at LEP. The branching ratio BR (b -> Bbar) x BR (Bbar -> D^0_1 l nu X) x BR (D^0_1 -> D^{*+} pi^-) is measured to be (2.64 +- 0.79 (stat) +- 0.39 (syst)) X 10^
M. Apollonio, A. Baldini, C. Bemporad, E. Caffau
This final article about the CHOOZ experiment presents a complete description of the electron antineutrino source and detector, the calibration methods and stability checks, the event reconstruction procedures and the Monte Carlo simulation. The data analysis, systematic effects and the methods used to reach our conclusions are fully discussed. Some new rema
L. H. Ford
The singularity theorems of classical general relativity are briefly reviewed. The extent to which their conclusions might still apply when quantum theory is taken into account is discussed. There are two distinct quantum loopholes: quantum violation of the classical energy conditions, and the presence of quantum fluctuations of the spacetime geometry. The p
Qingguo Zheng
A Script Language in this paper is designed to transform the original data into the target data by the computing formula. The Script Language can be translated into the corresponding SQL Language, and the computation is finally implemented by the first type of dynamic SQL. The Script Language has the operations of insert, update, delete, union, intersect, an
Superfluid--Insulator Transition in Commensurate Disordered Bosonic Systems:Large-Scale Worm-Algorithm Simulations
cond-matNikolay Prokof'ev, Boris Svistunov
We report results of large-scale Monte Carlo simulations of superfluid--insulator transitions in commensurate 2D bosonic systems. In the case of off-diagonal disorder (quantum percolation), we find that the transition is to a gapless incompressible insulator, and its dynamical critical exponent is $z=1.65 \pm 0.2$. In the case of diagonal disorder, we prove
Dirk Helbing
Physical concepts developed to describe instabilities in traffic flows can be generalized in a way that allows one to understand the well-known instability of supply chains (the so-called ``bullwhip effect''). That is, small variations in the consumption rate can cause large variations in the production rate of companies generating the requested prod
Coexistence of Composite-Bosons and Composite-Fermions in nu=1/2 + 1/2 Quantum Hall Bilayers
cond-mat.mes-hallSteven H. Simon, E. H. Rezayi, Milica Milovanovic
In bilayer quantum Hall systems at filling fractions near nu=1/2+1/2, as the spacing d between the layers is continuously decreased, intra-layer correlations must be replaced by inter-layer correlations, and the composite fermion (CF) Fermi seas at large d must eventually be replaced by a composite boson (CB) condensate or "111 state" at small d. We
Impulse distributions in dense granular flows: signatures of large-scale spatial structures
cond-mat.softA. Ferguson, B. Fisher, B. Chakraborty
In this paper we report the results of simulations of a 2D gravity driven, dissipative granular flow through a hopper system. Measurements of impulse distributions P(I) on the simulated system show flow-velocity-invariant behavior of the distribution for impulses larger than the average impulse <I>. For small impulses, however, P(I) decreases significantly w
Th. Busch, G. Huyet
We investigate degenerate quantum gases in one dimension trapped in a harmonic potential that is split in the centre by a pointlike potential. Since the single particle eigenfunctions of such a system are known for all strengths of the central potential, the dynamics for non-interacting fermionic gases and low-density, strongly interacting bosonic gases can
First-Principles Investigation of Perfect and Diffuse Anti-Phase Boundaries in HCP-Based Ti-Al Alloys
cond-mat.stat-mechA. van de Walle, M. Asta
First-principles thermodynamic models based on the cluster expansion formalism, monte-carlo simulations and quantum-mechanical total energy calculations are employed to compute short-range-order parameters and diffuse-antiphase-boundary energies in hcp-based $α$-Ti-Al alloys. Our calculations unambiguously reveal a substantial amount of SRO is present in $α$
Electron-Hole Correlations and Optical Excitonic Gaps in Quantum-Dot Quantum Wells: Tight-Binding Approach
cond-mat.mtrl-sciRui-Hua Xie, Garnett W. Bryant, Seungwon Lee, W. Jaskolski
Electron-hole correlation in quantum-dot quantum wells (QDQW's) is investigated by incorporating Coulomb and exchange interactions into an empirical tight-binding model. Sufficient electron and hole single-particle states close to the band edge are included in the configuration to achieve convergence of the first spin-singlet and triplet excitonic energi
First-principles calculation of the effect of strain on the diffusion of Ge adatoms on Si and Ge (001) surfaces
cond-mat.stat-mechA. van de Walle, M. Asta, P. W. Voorhees
First-principles calculations are used to calculate the strain dependencies of the binding and diffusion-activation energies for Ge adatoms on both Si(001) and Ge(001) surfaces. Our calculations reveal that the binding and activation energies on a strained Ge(001) surface increase and decrease, respectively, by 0.21 eV and 0.12 eV per percent compressive str
Systematic theoretical study of the spin and orbital magnetic moments of 4d and 5d interfaces with Fe films
cond-mat.mtrl-sciR. Tyer, G. van der Laan, W. M. Temmerman, Z. Szotek
Results of ab initio calculations using the relativistic Local Spin Density theory are presented for the magnetic moments of periodic 5d and 4d transition metal interfaces with bcc Fe(001). In this systematic study we calculated the layer-resolved spin and orbital magnetic moments over the entire series. For the Fe/W(001) system, the Fe spin moment is reduce
Electronic, vibrational and magnetic properties of a novel C_{48}N_{12} aza-fullerene
cond-mat.mtrl-sciRui-Hua Xie, Garnett W. Bryant, Vedene H. Smith
We study the structural, electronic, vibrational and magnetic properties of a novel ${\rm C}_{48}{\rm N}_{12}$ aza-fullerene using density functional theory and restricted Hartree-Fock theory. Optimized geometries and total energy of this fullerene have been calculated. We find that for ${\rm C}_{48}{\rm N}_{12}$ the total ground state energy is about -67617
P. Rodiere, J. P. Brison, A. D. Huxley, F. Rullier Albenque
We present transport and specific heat measurements on high quality single crystals of UPt$_3$ before and after irradiation by high energy electrons. We observe a strong dependence of the critical temperature with the sample thickness. The dramatic effects of the irradiation on the specific heat in the superconducting state can then be simply explained in te