March 2008 arXiv papers — page 33
Showing 3,201–3,300 of 4,524 papers
Collective multipole expansions and the perturbation theory in the quantum three-body problem
physics.atom-phA. V. Meremianin
The perturbation theory with respect to the potential energy of three particles is considered. The first-order correction to the continuum wave function of three free particles is derived. It is shown that the use of the collective multipole expansion of the free three-body Green function over the set of Wigner $D$-functions can reduce the dimensionality of
Raphaël Plasson, Hugues Bersini, Axel Brandenburg
The analysis of complex reaction networks is of great importance in several chemical and biochemical fields (interstellar chemistry, prebiotic chemistry, reaction mechanism, etc). In this article, we propose to simultaneously refine and extend for general chemical reaction systems the formalism initially introduced for the description of metabolic networks.
Abundance stratification in Type Ia Supernovae - II: The rapidly declining, spectroscopically normal SN 2004eo
astro-phP. A. Mazzali, D. N. Sauer, A. Pastorello, S. Benetti
The variation of properties of Type Ia supernovae, the thermonuclear explosions of Chandrasekhar-mass carbon-oxygen white dwarfs, is caused by different nucleosynthetic outcomes of these explosions, which can be traced from the distribution of abundances in the ejecta. The composition stratification of the spectroscopically normal but rapidly declining SN200
Yannick Sire, Enrico Valdinoci
We consider a quasilinear equation given in the half-space, i.e. a so called boundary reaction problem. Our concerns are a geometric Poincaré inequality and, as a byproduct of this inequality, a result on the symmetry of low-dimensional bounded stable solutions, under some suitable assumptions on the nonlinearities. More precisely, we analyze the following b
P. Rousselot
Context. More than ten Centaurs are now known to have cometary activity at large heliocentric distance (i.e. $\simeq$ 5-13 AU). Among these objects, 174P/Echeclus which showed cometary activity at 13 AU from the Sun, is a unique case, because of: (i) the amplitude of its outburst, (ii) the source of cometary activity that appears distinct from Echeclus itsel
N. Gonzalez-Lakunza, I. Fernandez-Torrente, K. J. Franke, N. Lorente
An electronic band with quasi-one dimensional dispersion is found at the interface between a monolayer of a charge-transfer complex (TTF-TCNQ) and a Au(111) surface. Combined local spectroscopy and numerical calculations show that the band results from a complex mixing of metal and molecular states. The molecular layer folds the underlying metal states and m
Shan-Gui Zhou, Jie Meng, Peter Ring
A deformed relativistic Hartree-Bogoliubov (DRHB) model is developed aiming at a proper description of exotic nuclei, particularly deformed ones with large spatial extension. In order to give an adequate description of both the contribution of the continuum and the large spatial distribution in exotic nuclei, the DRHB equations are solved in a Woods-Saxon ba
P. Oswiecimka, J. Kwapien, S. Drozdz, A. Z. Gorski
We perform an analysis of fractal properties of the positive and the negative changes of the German DAX30 index separately using Multifractal Detrended Fluctuation Analysis (MFDFA). By calculating the singularity spectra $f(α)$ we show that returns of both signs reveal multiscaling. Curiously, these spectra display a significant difference in the scaling pro
1E161348-5055 in the Supernova Remnant RCW 103: A Magnetar in a Young Low Mass Binary System?
astro-phFabio Pizzolato, Monica Colpi, Andrea De Luca, Sandro Mereghetti
We suggest that the unique X-ray source 1E161348-5055 at the centre of the supernova remnant RCW 103 consists of a neutron star in close orbit with a low mass main sequence star. The time signature of 6.67 hr is interpreted as the neutron star's spin period. This requires the neutron star to be endowed with a high surface magnetic field of~10^15 G. Magne
Yohsuke Murase, Takashi Shimada, Nobuyasu Ito, Per Arne Rikvold
Two mathematical models of macroevolution are studied. These models have population dynamics at the species level, and mutations and extinction of species are also included. The population dynamics are updated by difference equations with stochastic noise terms that characterize population fluctuations. The effects of the stochastic population fluctuations o
R. V. Gavai, Sourendu Gupta, R. Lacaze
We study screening correlators of quark-antiquark composites at T=2T_c, where T_c is the QCD phase transition temperature, using overlap quarks in the quenched approximation of lattice QCD. As the lattice spacing is changed from 1/4T to a=1/6T and 1/8T, we find that screening correlators change little, in contrast with the situation for other types of lattic
S. Yasui, S. H. Lee, K. Ohnishi, I. -K. Yoo
We propose the enhancement of $Λ_c$ yield in heavy ion collisions at RHIC and LHC as a novel signal for the existence of diquarks in the strongly coupled quark-gluon plasma produced in these collisions as well as in the $Λ_c$. Assuming that stable bound diquarks can exist in the quark-gluon plasma, we argue that the yield of $Λ_c$ would be increased by two-b
Markus Hegland, Robert S. Anderssen
Operationally, index functions of variable Hilbert scales can be viewed as generators for families of spaces and norms. Using a one parameter family of index functions based on the dilations of a given index function, a new class of scales (dilational Hilbert scales (DHS)) is derived which generates new interpolatory inequalities (dilational interpolatory in
A. Boer, S. Dumitru
The problem of first order phase transitions in nanoscopic systems is investigated in the framework of Hill's nanothermodynamics. We obtain the equilibrium conditions and a generalized version of the Clapeyron-Clausius equation for a nanoscopic system which contains two phases. Our study is exemplified for the case when one of the phases consists of an i
Nadja Kutz
The article collects arguments for the necessity of a global academic internet platform, which is organized as a kind of ``global scientific parliament''. With such a constitution educational and research institutions will have direct means for communicating scientific results, as well as a platform for representing academia and scientific life in th
On flows associated to Sobolev vector fields in Wiener spaces: an approach à la DiPerna-Lions
math.APLuigi Ambrosio, Alessio Figalli
In this paper we extend the DiPerna-Lions theory on ODEs with Sobolev vector fields to the setting of abstract Wiener spaces.
Resonant electron heating and molecular phonon cooling in single C$_{60}$ junctions
cond-mat.mtrl-sciG. Schulze, K. J. Franke, A. Gagliardi, G. Romano
We study heating and heat dissipation of a single \c60 molecule in the junction of a scanning tunneling microscope (STM) by measuring the electron current required to thermally decompose the fullerene cage. The power for decomposition varies with electron energy and reflects the molecular resonance structure. When the STM tip contacts the fullerene the molec
Parallelism of quantum computations from prequantum classical statistical field theory (PCSFT)
quant-phAndrei Khrennikov
This paper is devoted to such a fundamental problem of quantum computing as quantum parallelism. It is well known that quantum parallelism is the basis of the ability of quantum computer to perform in polynomial time computations performed by classical computers for exponential time. Therefore better understanding of quantum parallelism is important both for
Probabilistic signatures of spatiotemporal intermittency in the coupled sine circle map lattice
nlin.CDZahera Jabeen, Neelima Gupte
The phase diagram of the coupled sine circle map lattice exhibits a variety of interesting phenomena including spreading regions with spatiotemporal intermittency, non-spreading regions with spatial intermittency, and coherent structures termed solitons. A cellular automaton mapping of the coupled map lattice maps the spreading to non-spreading transition to
J. Goyon, A. Colin, G. Ovarlez, A. Ajdari
Amorphous glassy materials of diverse nature -- concentrated emulsions, granular materials, pastes, molecular glasses -- display complex flow properties, intermediate between solid and liquid, which are at the root of their use in many applications. A classical feature, well documented yet not really understood, is the very non-linear nature of the flow rule
Joonwoo Bae, Jeong San Kim
Quantum correlations as the resource for quantum communication can be distributed over long distances by quantum repeaters. In this Letter, we introduce the notion of a noisy quantum repeater, and examine its role in quantum communication. Quantum correlations shared through noisy quantum repeaters are then characterized and their secrecy properties are stud
Nir Barnea
Dynamical mean-field approximation with explicit pairing is utilized to study the properties of a two-component Fermi gas at unitarity. The problem is approximated by the lattice Hubbard Hamiltonian, and the continuum limit is realized by diluting the lattice. We have found that at zero temperature the predictions of this theory for the energy and the pairin
Jaya NN Iyer
In this note, we report on a work jointly done with C. Simpson on a generalization of Reznikov's theorem which says that the Chern-Simons classes and in particular the Deligne Chern classes (in degrees $> 1$) are torsion, of a flat vector bundle on a smooth complex projective variety. We consider the case of a smooth quasi--projective variety with an irr
Takuro Mochizuki
We prove the algebraic version of a conjecture of C. Sabbah on the existence of the good formal structure for meromorphic flat connections on surfaces after some blow up.
Diptiman Sen, Amit Agarwal
We present a microscopic model for a line junction formed by counter or co-propagating single mode quantum Hall edges corresponding to different filling factors. The ends of the line junction can be described by two possible current splitting matrices which are dictated by the conditions of both lack of dissipation and the existence of a linear relation betw
Sebastien G. R. Louis, Andrew D. Greentree, W. J. Munro, Kae Nemoto
We describe two protocols for efficient data transmission using a single passive bus. Different types of interactions are obtained enabling deterministic transfer and teleportation of composite quantum systems for arbitrary subsystem dimension and for arbitrary numbers of subsystems. The subsystems may become entangled in the transmission in which case the p
Jun-Jun Liang, Chao Zhang
As a limiting case of ultracold atoms trapped in deep optical lattices, we consider two interacting atoms trapped in a general anisotropic harmonic oscillator potential, and obtain exact solutions of the Schrodinger equation for this system. The energy spectra for different geometries of the trapping potential are compared.
Chong-Xing Yue, Jia Wen, Jin-Yan Liu, Wei Liu
Based on calculating the contributions of the littlest Higgs model with T-parity (called $LHT$ model) to the anomalous top coupling $tqγ$ ($q=u$ or $c$), we consider single top production via the t-channel partonic process $eq\to et$ at $ep$ collision. Our numerical results show that the production cross section in the $LHT$ model can be significantly enhanc
Alexandra Pettet, Juan Souto
We prove that the well-rounded retract of SO_n\SL_n(R) is a minimal SL_n(Z)-invariant spine.
Huy Tai Ha, Susan Morey, Rafael H. Villarreal
There is a one-to-one correspondence between square-free monomial ideals and clutters, which are also known as simple hypergraphs. It was conjectured that unmixed admissible clutters are Cohen-Macaulay. We prove the conjecture for uniform admissible clutters of heights 2 and 3. For admissible clutters of greater heights, we give a family of examples to show
Nir Avni
Let G be an arithmetic lattice in a semisimple algebraic group over a number field. We show that if G has the congruence subgroup property, then the number of n-dimensional irreducible representations of G grows like n^a, where a is a rational number.
Henri Moscovici, Bahram Rangipour
We associate to each infinite primitive Lie pseudogroup a Hopf algebra of `transverse symmetries', by refining a procedure due to Connes and the first author in the case of the general pseudogroup. The affiliated Hopf algebra can be viewed as a `quantum group' counterpart of the infinite-dimensional primitive Lie algebra of the pseudogroup. It is fir
Examples of area-minimizing surfaces in the subriemannian Heisenberg group H^1 with low regularity
math.DGManuel Ritoré
We give new examples of entire area-minimizing t-graphs in the subriemannian Heisenberg group H^1. Most of the examples are locally lipschitz in Euclidean sense. Some regular examples have prescribed singular set consisting of either a horizontal line or a finite number of horizontal halflines extending from a given point. Amongst them, a large family of are
Miguel Sánchez
We argue that, ideally, the ways to measure magnitudes in non-quantum theories of physics (spacetime, field theory), limit drastically their possible mathematical models. In particular, gauge invariance in the Yang-Mills framework, is a necessity of our way of measuring rather than an a priori imposition on symmetry. A general postulational basis for the geo
Simon Cox, François Graner, M. F. Vaz
Using the Surface Evolver software, we perform numerical simulations of point-like deformations in a two-dimensional foam. We study perturbations which are infinitesimal or finite, isotropic or anisotropic, and we either conserve or do not conserve the number of bubbles. We measure the displacement fields around the perturbation. Changes in pressure decrease
Serge Galam
The claimed unanimity of the scientific community about the human culpability for global warming is questioned. Up today there exists no scientific proof of human culpability. It is not the number of authors of a paper, which validates its scientific content. The use of probability to assert the degree of certainty with respect the global warming problem is
Andre Drews, Benjamin Krueger, Markus Bolte, Guido Meier
Antivortices in ferromagnetic thin-film elements are in-plane magnetization configurations with a core pointing perpendicular to the plane. By using micromagnetic simulations, we find that magnetic antivortices gyrate on elliptical orbits similar to magnetic vortices when they are excited by alternating magnetic fields or by spin-polarized currents. The phas
Paweł Konieczny
The paper examines the issue of existence of solutions to the steady Navier-Stokes equations in an exterior domain in $\mathbb{R}^2$. The system is studied with nonhomogeneous slip boundary conditions. The main results proves the existence of weak solutions for arbitrary data.
Optical properties of silicon carbide for astrophysical applications I. New laboratory infrared reflectance spectra and optical constants
astro-phK. M. Pitman, A. M. Hofmeister, A. B. Corman, A. K. Speck
Silicon Carbide (SiC) optical constants are fundamental inputs for radiative transfer models of astrophysical dust environments. However, previously published values contain errors and do not adequately represent the bulk physical properties of the cubic (beta) SiC polytype usually found around carbon stars. We provide new, uncompromised optical constants fo
Iosif Bena, Nikolay Bobev, Nicholas P. Warner
We discuss "spectral flow" coordinate transformations that take asymptotically four-dimensional solutions into other asymptotically four-dimensional solutions. We find that spectral flow can relate smooth three-charge solutions with a multi-center Taub-NUT base to solutions where one or several Taub-NUT centers are replaced by two-charge supertubes,
J. E. Hirsch
In recent work we formulated a new set of electrodynamic equations for superconductors as an alternative to the conventional London equations, compatible with the prediction of the theory of hole superconductivity that superconductors expel negative charge from the interior towards the surface. Charge expulsion results in a macroscopically inhomogeneous char
Simeon Hellerman, Martin Schnabl
We use open string field theory to study the dynamics of unstable branes in the bosonic string theory, in the background of a generic linear dilaton. We find a simple exact solution describing a dynamical interpolation between the perturbative vacuum and the recently discovered nonperturbative tachyon vacuum. In our solution, the open string tachyon increase
Andrei Gruzinov
We describe a scenario for large-scale magnetic field generation and particle acceleration in a collisionless collision of cold plasma clouds. A first-principle (i.e. using particles) numerical simulation of this process might be possible. Our scenario is essentially 3D. We argue that {\it large-scale} magnetic fields are not generated in 2D, even in collisi
J. F. Chapman, M. Wardle, T. J. Millar, M. G. Burton
We present results from a time dependent gas phase chemical model of a hot core based on the physical conditions of G305.2+0.2. While the cyanopolyyne HC_3N has been observed in hot cores, the longer chained species, HC_5N, HC_7N, and HC_9N have not been considered typical hot core species. We present results which show that these species can be formed under
M. Domokos
A close connection between the no-name lemma (concerning algebraic groups acting on vector bundles) and the existence of sufficiently many independent rational covariants is pointed out. In particular, this leads to a new natural proof of the no-name lemma. For linearly reductive groups, the approach has a refined variant based on integral covariants. This f
Eugene V. Stefanovich
The Darwin-Breit Hamiltonian is applied to the Aharonov-Bohm experiment. In agreement with the standard Maxwell-Lorentz theory, the force acting on electrons from infinite solenoids or ferromagnetic rods vanishes. However, the interaction energies and phase factors of the electron wave packets are non-zero. This allows us to explain the Aharonov-Bohm effect
H. Park, K. Haule, G. Kotliar
We address the nature of the Mott transition in the Hubbard model at half-filling using cluster Dynamical Mean Field Theory (DMFT). We compare cluster DMFT results with those of single site DMFT. We show that inclusion of the short range correlations on top of the on-site correlations, already treated exactly in single site DMFT, do not change the nature of
Samir Medina Perlaza, Laura Cottatellucci, Merouane Debbah
In this contribution we present a decentralized power allocation algorithm for the uplink interleave division multiple access (IDMA) channel. Within the proposed optimal strategy for power allocation, each user aims at selfishly maximizing its own utility function. An iterative chip by chip (CBC) decoder at the receiver and a rational selfish behavior of all
Heesang Park, Jongil Park, Dongsoo Shin
This paper is an addendum to [4], in which the authors constructed a simply connected minimal complex surface of general type with p_g=0 and K^2=3. In this paper we construct a new non-simply connected minimal surface of general type with p_g=0, K^2=3 and H_1=Z/2Z using a rational blow-down surgery and Q-Gorenstein smoothing theory.
Fedor V. Fomin, Yngve Villanger
For a given graph G and integers b,f >= 0, let S be a subset of vertices of G of size b+1 such that the subgraph of G induced by S is connected and S can be separated from other vertices of G by removing f vertices. We prove that every graph on n vertices contains at most n\binom{b+f}{b} such vertex subsets. This result from extremal combinatorics appears to
Shuo Yang, Shi-Jian Gu, Chang-Pu Sun, Hai-Qing Lin
We study exactly both the ground-state fidelity susceptibility and bond-bond correlation function in the Kitaev honeycomb model. Our results show that the fidelity susceptibility can be used to identify the topological phase transition from a gapped A phase with Abelian anyon excitations to a gapless B phase with non-Abelian anyon excitations. We also find t
Manuel Ritoré
Let $D$ be a closed disk centered at the origin in the horizontal hyperplane $\{t=0\}$ of the sub-Riemannian Heisenberg group $\hh^n$, and $C$ the vertical cylinder over $D$. We prove that any finite perimeter set $E$ such that $D\subset E\subset C$ has perimeter larger than or equal to the one of the rotationally symmetric sphere with constant mean curvatur
D. J. P. Morris, M. Roger, M. J. Gutmann, J. P. Goff
The sodium reordering in NaxCoO2 in the vicinity of room temperature is rationalized at high x in terms of phase transitions between square and striped phases. A striking hexagon-of-hexagons diffraction pattern observed for x=0.78 can be reproduced using coexisting square and striped phases that are related by simple shear deformations. All compositions exhi
Reconstructing the universe history, from inflation to acceleration, with phantom and canonical scalar fields
hep-thEmilio Elizalde, Shin'ichi Nojiri, Sergei D. Odintsov, Diego Sáez-Gómez
We consider the reconstruction technique in theories with a single or multiple (phantom and/or canonical) scalar fields. With the help of several examples, it is demonstrated explicitly that the universe expansion history, unifying early-time inflation and late-time acceleration, can be realized in scalar-tensor gravity. This is generalized to the theory of
Jean-François Jaulent
We compute the Galois group of the maximal 2-ramified pro-2-extension of a 2-rational number field
Zeldovich Lambda and Weinberg Relation: An Explanation for the Cosmological Coincidences
physics.gen-phAntonio Alfonso-Faus
In 1937 Dirac proposed the large number hypothesis (LNH). The idea was to explain that these numbers were large because the Universe is old. A time variation of certain constants was assumed. So far, no experimental evidence has significantly supported this time variation. Here we present a simplified cosmological model. We propose a new cosmological system
Stefan Christlmeier, Harald W. Griesshammer
In view of its relation to Big-Bang Nucleo-Synthesis and a reported discrepancy between nuclear models and data taken at S-DALINAC, electro-induced deuteron break-up 2H(e,e' p)n is studied at momentum transfer q<100MeV and close to threshold in the low-energy nuclear Effective Field Theory without dynamical pions. The result at N2LO for electric dipole c
Sergei A. Klioner
This work gives an explicit exact expression for the Thomas precession arising in the framework of Special Theory of Relativity as the spatial rotation resulting from two subsequence Lorentz boosts. The final result for the orthogonal matrix of Thomas precession is given by Eqs. (21)--(25). A trivial calculation leads to the compact formula (26) for the angl
Rational structure on algebraic tangles and closed incompressible surfaces in the complements of algebraically alternating knots and links
math.GTMakoto Ozawa
Let $F$ be an incompressible, meridionally incompressible and not boundary-parallel surface with boundary in the complement of an algebraic tangle $(B,T)$. Then $F$ separates the strings of $T$ in $B$ and the boundary slope of $F$ is uniquely determined by $(B,T)$ and hence we can define the slope of the algebraic tangle. In addition to the Conway's tang
Dean Lee
We consider two-component fermions on the lattice in the unitarity limit. This is an idealized limit of attractive fermions where the range of the interaction is zero and the scattering length is infinite. Using Euclidean time projection, we compute the ground state energy using four computationally different but physically identical auxiliary-field methods.
Leonardo Marazzi
We study inverse scattering for $Δ_g+V$ on $(X,g)$ a conformally compact manifold with metric $g,$ with variable sectional curvature $-\alf^2(y)$ at the boundary and $V\in C^\infty(X)$ not vanishing at the boundary. We prove that the scattering matrix at a fixed energies $(λ_1,$ $λ_2)$ in a suitable subset of $\mc$, determines $\alf,$ and the Taylor series o
Xiang Liu, Yan-Rui Liu, Wei-Zhen Deng, Shi-Lin Zhu
We reexamine whether $Z^+(4430)$ could be a $D_1'-{D}^*$ or $D_1-{D}^*$ molecular state after considering both the pion and $σ$ meson exchange potentials and introducing the form factor to take into account the structure effect of the interaction vertex. Our numerical analysis with Matlab package MATSLISE indicates the contribution from the sigma meson e
Tigran Hakobyan, Armen Nersessian
We give a simple geometric explanation for the similarity transformation mapping one-dimensional conformal mechanics to free-particle system. Namely, we show that this transformation corresponds to the inversion of the Klein model of Lobachevsky space (non-compact complex projective plane). We also extend this picture to the N=2k superconformal mechanics des
Takuya Matsumoto, Sanefumi Moriyama
In the su(2|2) spin chain motivated by the AdS/CFT correspondence, a novel symmetry extending the superalgebra su(2|2) into u(2|2) was found. We pursue the origin of this symmetry in the exceptional superalgebra d(2,1;epsilon), which recovers su(2|2) when the parameter epsilon is taken to zero. Especially, we rederive the Yangian symmetries of the AdS/CFT sp
Upper critical field, Hall effect and magnetoresistance in the iron-based layered superconductor LaFeAsO_{0.9}F_{0.1-δ}
cond-mat.supr-conXiyu Zhu, Huan Yang, Lei Fang, Gang Mu
By using a two-step method, we successfully synthesized the iron based new superconductor LaFeAsO_{0.9}F_{0.1-δ}$. The resistive transition curves under different magnetic fields were measured, leading to the determination of the upper critical field Hc2(T) of this new superconductor. The value of Hc2 at zero temperature is estimated to be about 50 Tesla rou
M. Mohammadi Najafabadi, S. Paktinat Mehdiabadi
In theories with large extra dimension and with low quantum gravity scale near a TeV, it is expected that TeV-scale black holes to be produced in proton-proton collisions at the LHC with the center of mass energy of 14 TeV. Since the black holes temperature can be around 1 TeV, top quark production is expected from them via Hawking radiation. Within the Stan
Doping-dependent Phase Diagram of LaO{\it M}As ({\it M}=V--Cu) and Electron-type Superconductivity near Ferromagnetic Instability
cond-mat.supr-conGang Xu, Wenmei Ming, Yugui Yao, Xi Dai
By first-principles calculations, we present a doping-dependent phase diagram of LaO{\it M}As ({\it M}=V--Cu) family. It is characterized as antiferromagnetic semiconductor around LaOMnAs side and ferromagnetic metal around LaOCoAs. Both LaOFeAs and LaONiAs, where superconductivity were discovered, are located at the borderline of magnetic phases. Extensive
Jean Ruppenthal
Let X be a regular irreducible variety in CP^{n-1}, Y the associated homogeneous variety in C^n, and N the restriction of the universal bundle of CP^{n-1} to X. In the present paper, we compute the obstructions to solving the d-bar-equation in the L^p-sense on Y for 1<=p<=\infty in terms of cohomology groups H^q(X,O(N^m)). That allows to identify obstruction
Jean Ruppenthal
In this paper, we define a Dolbeault complex with weights according to normal crossings, which is a useful tool for studying the d-bar-equation on singular complex spaces by resolution of singularities (where normal crossings appear naturally). The major difficulty is to prove that this complex is locally exact. We do that by constructing a local d-bar-solut
Mrinal Raghupathi
Given an inner function $B$ we classify the invariant subspaces of the algebra $H^\infty_B:=\mathbb{C}+BH^\infty$. We derive a formula in terms of these invariant subspaces for the distance of an element in $L^\infty$ to a certain weak*-closed ideal in $H^\infty_B$ and use this to prove an analogue of the Nevanlinna-Pick interpolation theorem.
Maxim V. Polyakov, Marc Vanderhaeghen
We study recent Deeply Virtual Compton scattering (DVCS) data within a dual parameterization of the Generalized Parton Distributions (GPDs). This parameterization allows to quantify the maximum amount of information, that can be extracted from DVCS data, in a ``quintessence'' function. We present a ``zero step'' model for the latter solely ba
Entropy driven stabilization of energetically unstable crystal structures explained from first principles theory
cond-mat.stat-mechP. Souvatzis, O. Eriksson, M. I. Katsnelson, S. P. Rudin
Conventional methods to calculate the thermodynamics of crystals evaluate the harmonic phonon spectra and therefore do not work in frequent and important situations where the crystal structure is unstable in the harmonic approximation, such as the body-centered cubic (bcc) crystal structure when it appears as a high-temperature phase of many metals. A method
Bernhard Steffen, Armin Seyfried
Pedestrian movements can be modeled at different degrees of detail. While flux models (Predeshensky/Milinski 1971) and cellular automata models (Schreckenberg 2002) give answers to some important questions and are fast and easy to use, continuous space modeling has the potential of full flexibility in geometry and realistic description of individual movement
Peter Constantin, Gautam Iyer, Jiahong Wu
In this paper, we consider the modified quasi-geostrophic equation \begin{gather*} \del_t θ+ (u \cdot \grad) θ+ κΛ^αθ= 0 u = Λ^{α- 1} R^{\perp}θ. \end{gather*} with $κ> 0$, $α\in (0,1]$ and $θ_0 \in \lp{2}(\R^2)$. We remark that the extra $Λ^{α- 1}$ is introduced in order to make the scaling invariance of this system similar to the scaling invariance of the
Igor Rivin
In this note we show the n-2-dimensional volumes of codimension 2 faces of an n-dimensional simplex are algebraically independent functions of the lengths of edges. In order to prove this we compute the complete spectrum of a combinatorially interesting graph.
Marcus K. Benna, Igor R. Klebanov
The first part of these lectures contains an introductory review of the AdS/CFT duality and of its tests. Applications to thermal gauge theory are also discussed briefly. The second part is devoted to a review of gauge-string dualities based on various warped conifold backgrounds, and to their cosmological applications.
Pierre Delage, Christian Schroeder, Yu Jun Cui
Based on the concepts of the mechanics of unsaturated soils where capillary phenomena arise between the wetting fluid (water) and the non-wetting one (air), the subsidence of chalks containing oil (non-wetting fluid) during water injection (wetting fluid) is analysed. It is shown that the collapse phenomenon of unsaturated soils under wetting provides a phys
Pierre Delage, Yu Jun Cui
Experimental techniques of testing the mechanical properties of unsaturated soils are complex and difficult to conduct. As a consequence, complete sets of parameters that characterise the behaviour of unsaturated soils remain scarce and necessary. In this context, it has been found useful to gather the information obtained after some years of practice of the
More on Algebraic Structure of the Complete Partition Function for the $ Z_n $ - Potts Model, Part 1
math.GMA. K. Kwasniewski, W. Bajguz
In this first part of a larger review undertaking the results of the first author and a part of the second author doctor dissertation are presented. Next we plan to give a survey of a nowadays situation in the area of investigation. Here we report on what follows. Calculation of the partition function for any vector potts model is at first reduced to the cal
Donal F. Connon
In this paper we derive two expressions for the Hurwitz zeta function involving the complete Bell polynomials in the restricted case where q is a positive integer greater than 1. The arguments of the complete Bell polynomials comprise the generalised harmonic number functions. These in turn give rise to Euler-Hurwitz series which may then be used to determin
K. I. Kellermann, M. L. Lister, D. C. Homan, Y. Y. Kovalev
The major multi-epoch VLBA programs are described and discussed in terms of relativistic beaming models. Broadly speaking the observed kinematics are consistent with models having a parent population which is only mildly relativistic but with Lorentz factors extending up to about 30. While the collimation and acceleration appears to mainly occur close to the
Ion I. Cotaescu, Adrian Palcu
The Pisano-Pleitez-Frampton 3-3-1 model is revisited here within the framework of the general method for solving gauge models with high symmetries. This exact algebraical approach - proposed several years ago by one of us - was designed to include a minimal Higgs mechanism that spontaneously breaks the gauge symmetry up to the universal $U(1)_{em}$ electroma
Li-Hua Lu, You-Quan Li
The efficiency of converting two-species fermionic atoms into bosonic molecules is investigated in terms of mean-field Lagrangian density. We find that the STIRAP technique aided by Feshbach resonance is more effective than the bare Fechbach resonance for $^6$Li atoms rather than $^{40}$K atoms. We also make general consideration on the symmetry and its rele
On the Topology of the Restricted Delaunay Triangulation and Witness Complex in Higher Dimensions
cs.CGSteve Y. Oudot
It is a well-known fact that, under mild sampling conditions, the restricted Delaunay triangulation provides good topological approximations of 1- and 2-manifolds. We show that this is not the case for higher-dimensional manifolds, even under stronger sampling conditions. Specifically, it is not true that, for any compact closed submanifold M of R^n, and any
R. Liseau, C. Risacher, A. Brandeker, C. Eiroa
Only very few solar-type stars exhibiting an infrared excess and harbouring planets are known to date. Indeed, merely a single case of a star-planet-disk system has previously been detected at submillimeter (submm) wavelengths. Consequently, one of our aims is to understand the reasons for these poor statistics, i.e., whether these results reflected the comp
P. Visco, F. van Wijland, E. Trizac
We investigate the probability distribution function of the free flight time and of the number of collisions in a hard sphere gas at equilibrium. At variance with naive expectation, the latter quantity does not follow Poissonian statistics, even in the dilute limit which is the focus of the present analysis. The corresponding deviations are addressed both nu
Reply on ``Comment on neutrino-mixing interpretation of the GSI time anomaly''by C. Giunti, arXiv:0801.4639 [nucl-th]
nucl-thA. N. Ivanov, R. Reda, P. Kienle
Here we reply critically to the comments by Giunti (arXiv:0801.4639 [nucl-th]) and justify our explanation of the experimentally observed periodic interference term in the rate of the K-shell electron capture decay of the H-like ions 140Pr58+ and 142Pm60+ as a neutrino-flavour mixing.
Leonard Daus
We use the concept of a regular object with respect to another object in an arbitrary category, defined in \cite{dntd}, in order to obtain the transfer of regularity in the sense of Zelmanowitz between the categories $R-$mod and $S-$mod, when $S$ is an excellent extension of the ring $R$. Consequently, we obtain a result of \cite{ps}: if $S$ is an excellent
Quo-Shin Chi
The classification of isoparametric hypersurfaces with four principal curvatures in spheres in [2] hinges on a crucial characterization, in terms of four sets of equations of the 2nd fundamental form tensors of a focal submanifold, of an isoparametric hypersurface of the type constructed by Ferus, Karcher and Münzner. The proof of the characterization in [2]
A. Neklyudov
We consider the abstract Cauchy problem x'=Ax, x(0)=x_0\in D(A) for linear operators A on a Banach space X. We prove uniqueness of the (local) solution of this problem for a natural class of operators A. Moreover, we establish that the solution x(\cdot) can be represented as a limit of sequence F(t/n)^{n} as n\to\infty in the weak operator topology, wher
Asit K. De, A. Harindranath, Jyotirmoy Maiti
Dependence of $a/r_c$ (inverse Sommer parameter in units of lattice spacing $a$) on $am_q$ (quark mass in lattice unit) has been observed in all lattice QCD simulations with sea quarks including the ones with improved actions. How much of this dependence is a scaling violation has remained an intriguing question. Our approach has been to investigate the issu
K. Haule, J. H. Shim, G. Kotliar
We compute the electronic structure, momentum resolved spectral function and optical conductivity of the new superconductor LaO$_{1-x}$F$_x$FeAs within the combination of the Density functional theory and the Dynamical Mean Field Theory. We find that the compound in the normal state is a strongly correlated metal and the parent compound is a bad metal at the
Yuzo Maruyama, William E. Strawderman
We derive minimax generalized Bayes estimators of regression coefficients in the general linear model with spherically symmetric errors under invariant quadratic loss for the case of unknown scale. The class of estimators generalizes the class considered in Maruyama and Strawderman (2005) to include non-monotone shrinkage functions.
Ying Zhang, Shun-Zhi Wang, Qing Wang
Traditional Stueckelberg Mechanism is shown equivalent to set up a gauged U(1) chiral Lagrangian and fix special gauge. With this mechanism, the original electro-weak chiral Lagrangian is inlarged by including an extra U(1) symmetry to represent physics for $Z'$ boson. We build up complete list of electro-weak chiral Lagrangian up to order of $p^4$ inclu
Jeremy Bailin, William E. Harris
We present a new method to classify galaxies from large surveys like the Sloan Digital Sky Survey using inclination-corrected concentration, inclination-corrected location on the color-magnitude diagram, and apparent axis ratio. Explicitly accounting for inclination tightens the distribution of each of these parameters and enables simple boundaries to be dra
Composition Profiles within Al3Li and Al3Sc/Al3Li Nanoscale Precipitates in Aluminum
cond-mat.mtrl-sciMatthew E. Krug, David C. Dunand, David N. Seidman
An Al-11.3Li-0.11Sc (at. %) alloy was double-aged to induce first alpha'-Al3Sc and then delta'-Al3Li precipitates. Atom-probe tomography revealed both single-phase delta'-precipitates and core-shell alpha'/delta'-precipitates (with respective average radii of 16 and 27 nm, and respective volume fractions of 12 and 9%) conferring a high st
Hsin-Fang Chiang, Leslie W. Looney, Konstantinos Tassis, Lee G. Mundy
Using interferometric data from BIMA observations, combined with detailed modeling in Fourier space of the physical structures predicted by models, we constrain the circumstellar envelope parameters for four Class 0 young stellar objects, as well as their embedded circumstellar disks. The envelopes of these objects are still undergoing collapse, and theoreti
Michael Baake
It is a well-known fact that genetic sequences may contain sections with repeated units, called repeats, that differ in length over a population, with a length distribution of geometric type. A simple class of recombination models with single crossovers is analysed that result in equilibrium distributions of this type. Due to the nonlinear and infinite-dimen
LensPerfect: Gravitational Lens Massmap Reconstructions Yielding Exact Reproduction of All Multiple Images
astro-phD. Coe, E. Fuselier, N. Benitez, T. Broadhurst
We present a new approach to gravitational lens massmap reconstruction. Our massmap solutions perfectly reproduce the positions, fluxes, and shears of all multiple images. And each massmap accurately recovers the underlying mass distribution to a resolution limited by the number of multiple images detected. We demonstrate our technique given a mock galaxy cl
Cesar A. Rodriguez-Rosario, E. C. G. Sudarshan
We construct a non-Markovian canonical dynamical map that accounts for systems correlated with the environment. The physical meaning of not completely positive maps is studied to obtain a theory of non-Markovian quantum dynamics. The relationship between inverse maps and correlations with the environment is established. A generalized non-Markovian master equ