July 2009 arXiv papers — page 42
Showing 4,101–4,200 of 5,590 papers
Kaspar von Braun, Stephen R. Kane, David R. Ciardi
The probability that an existing planetary transit is detectable in one's data is sensitively dependent upon the window function of the observations. We quantitatively characterize and provide visualizations of the dependence of this probability as a function of orbital period upon several observing strategy and astrophysical parameters, such as length o
G. Nimtz
A macroscopic realization of the strange virtual particles is presented. The classical Helmholtz and the quantum mechanical Schrödinger equations are analogous differential equations. Their imaginary solutions are called evanescent modes in the case of elastic and electromagnetic fields. In the case of non-relativistic quantum mechanical fields they are call
Daniel Boer
Transverse polarization of Lambda hyperons produced in p p and p Pb collisions is discussed. A factorized description in the intermediate to high p_T region is considered that involves transverse momentum and spin dependence in the fragmentation process. Consequences and suggestions for investigations at LHC are pointed out for the process p + p -> Lambda^up
Raquel M. Lopez, Sergei K. Suslov, Erika T. Camacho
There are many natural, physical, and biological systems that exhibit multiple time scales. For example, the dynamics of a population of ticks can be described in continuous time during their individual life cycle yet discrete time is used to describe the generation of offspring. These characteristics cause the population levels to be reset periodically. A s
A. Cattaneo, S. M. Faber, J. Binney, A. Dekel
Virtually all massive galaxies, including our own, host central black holes ranging in mass from millions to billions of solar masses. The growth of these black holes releases vast amounts of energy that powers quasars and other weaker active galactic nuclei. A tiny fraction of this energy, if absorbed by the host galaxy, could halt star formation by heating
Valery Borovikov, Andrew Zangwill
The unique electronic properties of graphene offer the possibility that it could replace silicon when microelectronics evolves to nanoelectronics. Graphene grown epitaxially on silicon carbide is particularly attractive in this regard because SiC is itself a useful semiconductor and, by suitable manipulation of the growth conditions, epitaxial films can be p
Massimo Pica Ciamarra, Antonio Coniglio
Via molecular dynamics simulations, we unveil the hysteretic nature of the jamming transition of soft repulsive frictionless spheres, as it occurs varying the volume fraction or the shear stress. In a given range of control parameters the system may be found both in a flowing and in an jammed state, depending on the preparation protocol. The hysteresis is du
HJB Equations for the Optimal Control of Differential Equations with Delays and State Constraints, II: Optimal Feedbacks and Approximations
math.OCSalvatore Federico, Ben Goldys, Fausto Gozzi
This paper, which is the natural continuation of a previous paper by the same authors, studies a class of optimal control problems with state constraints where the state equation is a differential equation with delays. This class includes some problems arising in economics, in particular the so-called models with time to build. The problem is embedded in a s
Eric Schippers
The theory of formal power series and derivation is developed from the point of view of the power matrix. A Loewner equation for formal power series is introduced. We then show that the matrix exponential is surjective onto the group of power matrices, and the coefficients are entire functions of finitely many coefficients of the infinitesimal generator. Fur
Andrew D. Kent, Daniel L. Stein
An annular magnetic memory that uses a spin-polarized current to switch the magnetization direction or helicity of a magnetic region is proposed. The device has magnetic materials in the shape of a ring (1 to 5 nm in thickness, 20 to 250 nm in mean radius and 8 to 100 nm in width), comprising a reference magnetic layer with a fixed magnetic helicity and a fr
Zdenek Dvorak, Bojan Mohar
A conjecture of Richter and Salazar about graphs that are critical for a fixed crossing number $k$ is that they have bounded bandwidth. A weaker well-known conjecture of Richter is that their maximum degree is bounded in terms of $k$. In this note we disprove these conjectures for every $k\ge 171$, by providing examples of $k$-crossing-critical graphs with a
Rodrigo Banuelos, Pedro J. Mendez-Hernandez
It is shown that many of the classical generalized isoperimetric inequalities for the Laplacian when viewed in terms of Brownian motion extend to a wide class of Levy processes. The results are derived from the multiple integral inequalities of Brascamp, Lieb and Luttinger but the probabilistic structure of the processes plays a crucial role in the proofs.
M. Carmen Sánchez Gil, Emilio J. Alfaro, Enrique Pérez
The galaxy NGC 6946 contains a gas-star complex of 700 pc in diameter which appears populated by tens of young stellar clusters, and a Super Star Cluster (SSC) as massive as 10$^6$ M$\odot$. The ionized gas, as drawn by the H$α$ emission, delineates an almost circular shape which we show here to be in expansion. Previous studies have analyzed the stellar com
Renato Fedele, Bengt Eliasson, Fernando Haas, Padma Kant Shukla
We present a class of three-dimensional solitary waves solutions of the Gross-Pitaevskii (GP) equation, which governs the dynamics of Bose-Einstein condensates (BECs). By imposing an external controlling potential, a desired time-dependent shape of the localized BEC excitation is obtained. The stability of some obtained localized solutions is checked by solv
D. Baeriswyl, D. Eichenberger, M. Menteshashvili
Recent refinements of analytical and numerical methods have improved our understanding of the ground-state phase diagram of the two-dimensional (2D) Hubbard model. Here we focus on variational approaches, but comparisons with both Quantum Cluster and Gaussian Monte Carlo methods are also made. Our own ansatz leads to an antiferromagnetic ground state at half
Zdenek Dvorak, Bojan Mohar
It is well known that the spectral radius of a tree whose maximum degree is $D$ cannot exceed $2\sqrt{D-1}$. In this paper we derive similar bounds for arbitrary planar graphs and for graphs of bounded genus. It is proved that a the spectral radius $ρ(G)$ of a planar graph $G$ of maximum vertex degree $D\ge 4$ satisfies $\sqrt{D}\le ρ(G)\le \sqrt{8D-16}+7.75
Thermodynamics and Fluctuation Theorems for a Strongly Coupled Open Quantum System: An Exactly Solvable Case
cond-mat.stat-mechMichele Campisi, Peter Talkner, Peter Hänggi
We illustrate recent results concerning the validity of the work fluctuation theorem in open quantum systems [M. Campisi, P. Talkner, and P. Hänggi, Phys. Rev. Lett. {\bf 102}, 210401 (2009)], by applying them to a solvable model of an open quantum system. The central role played by the thermodynamic partition function of the open quantum system, -- a two le
T. Rajasekharan, V. Seshubai
Rajasekharan and Girgis reported that binary systems with intermetallic compounds of a particular crystal structure form a straight line on a map using Miedema parameters. In this paper, the universality of that observation is examined. Observations from a study of 143 binary systems that crystallize in six different crystal structures at AB3 composition are
S. Gandolfi, A. Yu. Illarionov, F. Pederiva, K. E. Schmidt
We report results of the equation of state of neutron matter in the low--density regime, where the Fermi wave vector ranges from $0.4 fm^{-1} \leq k_F \leq 1.0 fm^{-1}$. Neutron matter in this regime is superfluid because of the strong and attractive interaction in the $^1S_0$ channel. The properties of this superfluid matter are calculated starting from a r
Continuum multi-physics modeling with scripting languages: the Nsim simulation compiler prototype for classical field theory
physics.comp-phThomas Fischbacher, Hans Fangohr
We demonstrate that for a broad class of physical systems that can be described using classical field theory, automated runtime translation of the physical equations to parallelized finite-element numerical simulation code is feasible. This allows the implementation of multiphysics extension modules to popular scripting languages (such as Python) that handle
David M. South
High energy physics data is a long term investment and contains the potential for physics results beyond the lifetime of a collaboration. Many existing experiments are concluding their physics programs, and looking at ways to preserve their data heritage. Preservation of high-energy physics data and data analysis structures is a challenge, and past experienc
Marta Lewicka, Reza Pakzad
We summarize some recent results of the authors and their collaborators, regarding the derivation of thin elastic shell models (for shells with mid-surface of arbitrary geometry) from the variational theory of 3d nonlinear elasticity. We also formulate a conjecture on the form and validity of infinitely many limiting 2d models, each corresponding to its prop
Zdenek Dvorak, Bojan Mohar
Given a graphic degree sequence $D$, let $χ(D)$ (respectively $ω(D)$, $h(D)$, and $H(D)$) denote the maximum value of the chromatic number (respectively, the size of the largest clique, largest clique subdivision, and largest clique minor) taken over all simple graphs whose degree sequence is $D$. It is proved that $χ(D)\le h(D)$. Moreover, it is shown that
Wlodzimierz Zwonek
We extend and simplify results of \cite{Din~2009} where the asymptotic behavior of the holomorphic sectional curvature of the Bergman metric in annuli is studied. Similarly as in \cite{Din~2009} the description enables us to construct an infinitely connected planar domain (in our paper it is a Zalcman type domain) for which the supremum of the holomorphic se
Soon-Tae Hong
We exploit the 't Hooft-Polyakov monopole to define closed algebra of the quantum field operators and the BRST charge $Q_{BRST}$. In the first-class configuration of the Dirac quantization, by including the $Q_{BRST}$-exact gauge fixing term and the Faddeev-Popov ghost term, we find the BRST invariant Hamiltonian to investigate the de Rham-type cohomolog
Jacob D. Biamonte
The Lorentzian length of a timelike curve connecting both endpoints of a classical computation is a function of the path taken through Minkowski spacetime. The associated runtime difference is due to time-dilation: the phenomenon whereby an observer finds that another's physically identical ideal clock has ticked at a different rate than their own clock.
K. Szlachanyi
What are the fiber functors on small additive monoidal categories C which are not abelian? We give an answer which leads to a new Tannaka duality theorem for bialgebroids generalizing earlier results by Phung Ho Hai. The construction reveals a sheaf theoretic interpretation in so far as the reconstructed bialgebroid H has comodule category equivalent to the
Shmuel Nussinov, Robert Shrock
We discuss a notion of gluon-glueball duality analogous to quark-hadron duality. We apply this idea to the radiative decay of heavy orthoquarkonium, $Q\bar Q \to γg g$, which has been used to search for glueballs. The duality is first introduced in two simplified contexts: (i) a hypothetical version of QCD without any light quarks and (ii) QCD in the large-$
Kenjiro Yanagi
We give a trace inequality related to the uncertainty relation of Wigner-Yanase-Dyson skew information. This inequality corresponds to a generalization of the uncertainty relation derived by S. Luo for the quantum uncertainty quantity excluding the classical mixture.
Optical Properties of Correlated Materials -- or Why Intelligent Windows may look Dirty
cond-mat.str-elJan M. Tomczak, Silke Biermann
Materials with strong electronic Coulomb correlations play an increasing role in modern materials applications. "Thermochromic" systems, which exhibit thermally induced changes in their optical response, provide a particularly interesting case. The optical switching associated with the metal-insulator transition of vanadium dioxide, for example, has
Viktoriya V. Ivanovskaya, Alberto Zobelli, Odile Stephan, Patrick R. Briddon
We present a density functional theory study on the shape and arrangement of small BN domains embedded into single-walled carbon nanotubes. We show a strong tendency for the BN hexagons formation at the simultaneous inclusion of B and N atoms within the walls of carbon nanotubes. The work emphasizes the importance of a correct description of the BN-C frontie
Surface state bi-polarons formation on a triangular lattice in the sp-type alkali/Si(111) Mott insulator
cond-mat.str-elL. A. Cardenas, Y. Fagot-Revurat, L. Moreau, B. Kierren
We report on new LEED, STM and ARPES studies of alkali/Si(111) previously established as having a Mott insulating ground state at surface. The observation of a strong temperature dependent Franck-Condon broadening of the surface band together with the novel $\sqrt{3}\times\sqrt{3}\to2(\sqrt{3}\times\sqrt{3})$ charge and lattice ordering below 270 K evidence
Michel Weber
Let $ \{W(t), t\ge 0\}$ be a standard Brownian motion. If $I$ is a bounded interval on which $W $ has no zero, an almost sure lower bound to $\inf\{|W(t)|, t\in I\}$ can be provided, when $I$ is taken from a given countable family of intervals covering the positive half-line.
Artificial quantum-dot Helium molecules: Electronic spectra, spin structures, and Heisenberg clusters
cond-mat.mes-hallYing Li, Constantine Yannouleas, Uzi Landman
Energy spectra and spin configurations of a system of N=4 electrons in lateral double quantum dots (quantum dot Helium molecules) are investigated using exact diagonalization (EXD), as a function of interdot separation, applied magnetic field (B), and strength of interelectron repulsion. As a function of the magnetic field, the energy spectra exhibit a low-e
D. Lacoste, K. Mallick
Molecular motors convert chemical energy derived from the hydrolysis of ATP into mechanical energy. A well-studied model of a molecular motor is the flashing ratchet model. We show that this model exhibits a fluctuation relation known as the Gallavotti-Cohen symmetry. Our study highlights the fact that the symmetry is present only if the chemical and mechani
H. -H. Hasegawa, J. Ishikawa, K. Takara, D. J. Driebe
We generalize the second law of thermodynamics in its maximum work formulation for a nonequilibrium initial distribution. It is found that in an isothermal process, the Boltzmann relative entropy (H-function) is not just a Lyapunov function but also tells us the maximum work that may be gained from a nonequilibrium initial state. The generalized second law a
George Georgiou, Valeria L. Gili, Rodolfo Russo
We study the three-point functions between two BPS and one non-BPS local gauge invariant operators in N=4 Super Yang-Mills theory. In particular we show, in explicit 1-loop examples, that the operator mixing discussed in arXiv:0810.0499 plays an important role in the computations of the correlators and is necessary to cancel contributions that would violate
Tinggui Wang, Hongyan Zhou, Weimin Yuan, Honglin Lu
Quasar outflows may play important role in the evolution of its host galaxy and central black hole. In this paper, we present a detailed study of multiple outflows in the obscured ultra-luminous infrared quasar Q1321+058. The outflows reveal themselves in the complex optical and UV emission line spectrum, with a broad component blueshifted by 1650 km/s and a
Michał Karski, Leonid Förster, Jai-Min Choi, Andreas Steffen
The quantum walk is the quantum analogue of the well-known random walk, which forms the basis for models and applications in many realms of science. Its properties are markedly different from the classical counterpart and might lead to extensive applications in quantum information science. In our experiment, we implemented a quantum walk on the line with sin
R. Laugesen, B. Siudeja
We prove sharp isoperimetric inequalities for Neumann eigenvalues of the Laplacian on triangular domains. The first nonzero Neumann eigenvalue is shown to be maximal for the equilateral triangle among all triangles of given perimeter, and hence among all triangles of given area. Similar results are proved for the harmonic and arithmetic means of the first tw
Filippo Visco Comandini, Mazyar Mirrahimi, Michel Sorine
The Frequency Domain Reflectometry (FDR) is studied as a powerful tool to detect hard or soft faults in star-shaped networks of nonuniform lossless transmission lines. Processing the FDR measurements leads to solve an inverse scattering problem for a Schrodinger operator on a star-shaped graph. Throughout this paper, we restrict ourselves to the case of mini
Comment on "Spin-rotation coupling in non-exponential decay of hydrogenlike heavy ions" by G. Lambiase et al
nucl-thThomas Faestermann
I note that the explanation of a recently posted paper by Lambiase et al. [arXiv:0811.2302] for the oscillations in the electron capture decay rate, reported by Litvinov et al.[arXiv:0801.2079], requires the cancellation of a difference by eleven orders of magnitude for the two independent measurements. Such a cancellation is (impossible)^2.
A. Perez-Madrid, I. Santamaria-Holek
Based on Newton's laws reformulated in the Hamiltonian dynamics combined with statistical mechanics, we formulate a statistical mechanical theory supporting the hypothesis of a closed oscillating universe. We find that the behaviour of the universe as a whole can be represented by a free entropic oscillator whose lifespan is nonhomogeneous, thus implying
The Hamiltonian formulation of N-bein, Einstein-Cartan, gravity in any dimension: the Progress Report (Extended version of a talk given on CAIMS-2009, June 11-14, London, Canada)
gr-qcN. Kiriushcheva, S. V. Kuzmin
The Hamiltonian formulation of N-bein, Einstein-Cartan, gravity, using its first order form in any dimension higher than two, is analyzed. This Hamiltonian formulation allows to explicitly show where peculiarities of three dimensional case (\textit{A.M.Frolov et al, 0902.0856 [gr-qc]}) occur and make a conjecture, based on presented in this report results, t
R. Laugesen, B. Siudeja
The first nonzero eigenvalue of the Neumann Laplacian is shown to be minimal for the degenerate acute isosceles triangle, among all triangles of given diameter. Hence an optimal Poincaré inequality for triangles is derived. The proof relies on symmetry of the Neumann fundamental mode for isosceles triangles with aperture less than $π/3$. Antisymmetry is prov
Mohamed Elhamdadi, Abdenacer Makhlouf
The purpose of this paper is to introduce an algebraic cohomology and formal deformation theory of left alternative algebras. Connections to some other algebraic structures are given also.
Jesus Guillera
In this paper we prove theorems related to the Ramanujan-type series for $1/π$ (type $_3F_2$) and to the Ramanujan-like series, discovered by the author, for $1/π^2$ (type $_5F_4$). Our developments for the cases $_3 F_2$ and $_5 F_4$ connect with the theory of modular functions and with the theory of Calabi-Yau differential equations, respectively.
Se Baek Oh, George Barbastathis, Ramesh Raskar
The ray-based 4D light field representation cannot be directly used to analyze diffractive or phase--sensitive optical elements. In this paper, we exploit tools from wave optics and extend the light field representation via a novel "light field transform". We introduce a key modification to the ray--based model to support the transform. We insert a &
Lower bound on the spectrum of the Schrödinger operator in the plane with delta-potential supported by a curve
math.SPIgor Lobanov, Vladimir Lotoreichik, Igor Popov
We consider the Schrödinger operator in the plane with delta-potential supported by a curve. For the cases of an infinite curve and a finite loop we give estimates on the lower bound of the spectrum expressed explicitly through the strength of the interaction and a parameter which characterizes geometry of the curve. Going further we cut the curve into finit
Victor B. Putz, Julia M. Yeomans
We define a model microswimmer with a variable cycle time, thus allowing the possibility of phase locking driven by hydrodynamic interactions between swimmers. We find that, for extensile or contractile swimmers, phase locking does occur, with the relative phase of the two swimmers being, in general, close to 0 or pi, depending on their relative position and
A. M. D. McDougall, A. W. Hood
Mode conversion occurs when a wave passes through a region where the sound and Alfven speeds are equal. At this point there is a resonance, which allows some of the incident wave to be converted into a different mode. We study this phenomenon in the vicinity of a two-dimensional, coronal null point. As a wave approaches the null it passes from low- to high-b
Sonja Georgievska, Suzana Andova
A central paradigm behind process semantics based on observability and testing is that the exact moment of occurring of an internal nondeterministic choice is unobservable. It is natural, therefore, for this property to hold when the internal choice is quantified with probabilities. However, ever since probabilities have been introduced in process semantics,
H. S. Kohler
A microscopic theory of nuclei based on a 'free' scattering NN-potential is meaningful only if this potential fits on-shell scattering data.This is a necessary but not sufficient condition for the theory to be successful.It has been demonstrated repeatedly in the past that 2-body off-shell adjustments or many-body forces are necessary.It has been sho
Th. Jolicoeur
Some recently observed fractional quantum Hall states are not easily explained in standard hierarchy/composite fermion schemes. This paper gives a brief introduction to some wavefunctions involving non-Abelian Read-Rezayi states with negative flux that have been proposed as candidates for these new quantum Hall fractions.
Xiaoyan Gao, Jiancheng Wang, Jianping Yang
The spectral energy distribution (SED) of TeV blazars has a double-humped shape that is usually interpreted as Synchrotron Self Compton (SSC) model. The one zone SSC model is used broadly but cannot fit the high energy tail of SED very well. It need bulk Lorentz factor which is conflict with the observation. Furthermore one zone SSC model can not explain the
Antonio Racioppi
This Thesis reviews an extension of the MSSM by the addition of an anomalous abelian vector multiplet and contains some original results concerning the phenomenology of an anomalous $Z'$. The review part covers an introduction of the MSSM focusing on its main features, a discussion on the chiral anomalies and how to cancel them in the Standard Model and
A diffuse bubble-like radio-halo source MRC 0116+111: imprint of AGN feedback in a low-mass cluster of galaxies
astro-ph.COJoydeep Bagchi, Joe Jacob, Gopal-Krishna, Norbert Werner
We present detailed observations of MRC 0116+111, revealing a luminous, mini radio-halo of ~240 kpc diameter located at the centre of a cluster of galaxies at redshift z = 0.131. Our optical and multi-wavelength GMRT and VLA radio observations reveal a highly unusual radio source: showing a pair of giant (~100 kpc diameter) bubble-like diffuse structures, th
A new protein binding pocket similarity measure based on comparison of 3D atom clouds: application to ligand prediction
stat.MLBrice Hoffmann, Mikhail Zaslavskiy, Jean-Philippe Vert, Véronique Stoven
Motivation: Prediction of ligands for proteins of known 3D structure is important to understand structure-function relationship, predict molecular function, or design new drugs. Results: We explore a new approach for ligand prediction in which binding pockets are represented by atom clouds. Each target pocket is compared to an ensemble of pockets of known li
E. Macías-Virgós, M. J. Pereira-Sáez
We prove that given four arbitrary quaternion numbers of norm 1 there always exists a $2\times 2$ symplectic matrix for which those numbers are left eigenvalues. The proof is constructive. An application to the LS category of Lie groups is given.
B. De Marco, K. Iwasawa, M. Cappi, M. Dadina
The unprecedented sensitivity of current X-ray telescopes allows for the first time to address the issue of the Fe K line complex variability patterns in bright, nearby AGNs. We examine XMM-Newton observations of the brightest sources of the FERO sample of radio-quiet type 1 AGNs with the aim of characterizing the temporal behaviour of Fe K complex features.
Guy Metivier, Kevin Zumbrun
Using a weighted $H^s$-contraction mapping argument based on the macro-micro decomposition of Liu and Yu, we give an elementary proof of existence, with sharp rates of decay and distance from the Chapman--Enskog approximation, of small-amplitude shock profiles of the Boltzmann equation with hard-sphere potential, recovering and slightly sharpening results ob
Robert Schrader
Laplace operators on metric graphs give rise to Klein-Gordon and wave operators. Solutions of the Klein-Gordon equation and the wave equation are studied and finite propagation speed is established. Massive, free quantum fields are then constructed, whose commutator function is just the Klein-Gordon kernel. As a consequence of finite propagation speed Einste
Abhas Mitra
We start with a new version of Newtonian cosmology by incorporating the fact that the galaxies are losing mass due to emission of radiation. This yields accelerated recession for the galaxies. We point out that in the presence of accelerated expansion, the universe can be infinitely old and suggest that the observable universe is only a speckle of the true u
Mohamed El Machkouri, Radu Stoica
We establish the asymptotic normality of the regression estimator in a fixed-design setting when the errors are given by a field of dependent random variables. The result applies to martingale-difference or strongly mixing random fields. On this basis, a statistical test that can be applied to image analysis is also presented.
Alexander Pushnitski, Dmitri Yafaev
In the smooth scattering theory framework, we consider a pair of self-adjoint operators $H_0$, $H$ and discuss the spectral projections of these operators corresponding to the interval $(-\infty,λ)$. The purpose of the paper is to study the spectral properties of the difference $D(λ)$ of these spectral projections. We completely describe the absolutely conti
Alvaro Caso, Liliana Arrachea, Gustavo S. Lozano
We introduce thermometers to define the local temperature of an electronic system driven out-of-equilibrium by local AC fields. We also define the effective temperature in terms of a local fluctuation-dissipation-relation. We show that within the weak driving regime these two temperatures coincide. We also discuss the behavior of the local temperature along
Charge mobility determination by current extraction under linear increasing voltages: the case of non-equilibrium charges and field-dependent mobilities
cond-mat.mtrl-sciSebastian Bange, Marcel Schubert, Dieter Neher
The method of current extraction under linear increasing voltages (CELIV) allows for the simultaneous determination of charge mobilities and charge densities directly in thin films as used in organic photovoltaic cells (OPV). In the past, it has been specifically applied to investigate the interrelation of microstructure and charge transport properties in su
Kasper Peeters, Jonathan Powell, Marija Zamaklar
We explore a class of holographic superconductors built using non-abelian condensates on probe branes in conformal and non-conformal backgrounds. These are shown to exhibit behaviour of the specific heat which resembles that of heavy fermion compounds in the superconducting phase. Instead of showing BCS-like exponential behaviour, the specific heat is polyno
Connection with parallel totally skew-symmetric torsion on almost complex manifolds with Norden metric
math.DGDimitar Mekerov
In the present work we consider an almost complex manifold with Norden metric (i.e. a metric with respect to which the almost complex structure is an antiisometry). On such a manifold we study a linear connection preserving the almost complex structure and the metric and having a totally skew-symmetric torsion tensor. We consider the case when the manifold a
Osamu Fujino
We describe the foundation of the log minimal model program for log canonical pairs according to Ambro's idea. We generalize Kollár's vanishing and torsion-free theorems for embedded simple normal crossing pairs. Then we prove the cone and contraction theorems for quasi-log varieties, especially, for log canonical pairs.
The Spitzer c2d Survey of Nearby Dense Cores: VI. The Protostars of Lynds Dark Nebula 1221
astro-ph.GAChadwick H. Young, Tyler L. Bourke, Michael M. Dunham, Neal J. Evans
Observations of Lynds Dark Nebula 1221 from the Spitzer Space Telescope are presented. These data show three candidate protostars towards L1221, only two of which were previously known. The infrared observations also show signatures of outflowing material, an interpretation which is also supported by radio observations with the Very Large Array. In addition,
O. Gamayun, A. Marshakov
The first-order bosonic string theory, perturbed by primary operator, corresponding to the deformation of target-space complex structure is considered. We compute the correlation functions in this theory and study their divergencies. It is found, that consistency of these correlation functions with the world-sheet conformal invariance requires the Kodaira-Sp
Dimitar Mekerov
In the present work, we introduce a linear connection (preserving the almost product structure and the Riemannian metric) on Riemannian almost product manifolds. This connection, called P-connection, is an analogue of the first canonical connection of Lichnerowicz in the Hermitian geometry and the B-connection in the geometry of the almost complex manifolds
N. A. Krivova, S. K. Solanki, T. Wenzler, B. Podlipnik
Variations of the solar UV irradiance are an important driver of chemical and physical processes in the Earth's upper atmosphere and may also influence global climate. Here we reconstruct solar UV irradiance in the range 115-400 nm over the period 1974-2007 by making use of the recently developed empirical extension of the SATIRE models employing SUSIM data.
Andre Sopczak
For the preparation of the experimental search for charged Higgs bosons at the LHC detailed studies have been made to determine the expected charged Higgs boson production cross-sections and decay branching ratios at sqrts = 14 TeV. In the mass regime below the t-quark mass the expected production cross-sections are discussed using PYTHIA and FeynHiggs progr
Pierre Nolin
We further study the interfaces arising in a situation of inhomogeneity. More precisely, we identify a characteristic length for the gradient percolation model, that enables us to tighten previous estimates established for it. This allows to construct non-trivial scaling limits: the limiting objects share some properties with critical percolation interfaces,
Pawel Klaja
The COSY-11 collaboration measured the pp -> ppeta and pp -> ppeta' reactions in order to perform comparative studies of the interactions within the proton-proton-meson system. This thesis presents in detail the analysis of the pp -> ppeta' reaction which was measured at the proton beam momentum of 3.260 GeV/c. The elaboration results in differential
Robust coupling of superconducting order parameter in a mesoscale NbN-Fe-NbN epitaxial structure
cond-mat.supr-conS. K. Bose, R. C. Budhani
We report an unconventional and promising route to self-assemble distributed superconductor-ferromagnet-superconductor (S-F-S) Josephson Junctions on single crystal [100] MgO. These structures consist of [110] epitaxial nano-plaquettes of Fe covered with superconducting NbN films of varying thickness. The S-F-S structures are characterized by strong magnetor
C. G. Mundell, P. Ferruit, N. Nagar, A. S. Wilson
Comparison of 8.4-GHz radio images of a sample of 11 early-type Seyfert galaxies with previous observations reveals possible variation in the nuclear radio flux density in 5 of them over a 7-yr period. We find no correlation between radio variability and nuclear radio luminosity or Seyfert nuclear type, although the sample is small and dominated by type 2 Se
Goro Ishiki, Sang-Woo Kim, Jun Nishimura, Asato Tsuchiya
Recently a novel large-N reduction has been proposed as a maximally supersymmetric regularization of N=4 super Yang-Mills theory on RxS^3 in the planar limit. This proposal, if it works, will enable us to study the theory non-perturbatively on a computer, and hence to test the AdS/CFT correspondence analogously to the recent works on the D0-brane system. We
W. D. Apel
Extensive air showers are generated through interactions of high-energy cosmic rays impinging the Earth's atmosphere. A new method is described to infer the attenuation of hadrons in air showers. The numbers of electrons and muons, registered with the scintillator array of the KASCADE experiment are used to estimate the energy of the shower inducing prim
Arno Pauly
We investigate the degree of discontinuity of several solution concepts from non-cooperative game theory. While the consideration of Nash equilibria forms the core of our work, also pure and correlated equilibria are dealt with. Formally, we restrict the treatment to two player games, but results and proofs extend to the n-player case. As a side result, the
Carlo Hamalainen
In this note we introduce the concept of the trade space of a latin square. Computations using Sage and the GAP package Simplicial Homology are presented.
Ground states of anisotropic antiferromagnets with single ion and cubic anisotropy
cond-mat.stat-mechT. -C. Dinh, R. Folk
Anisotropic antiferromagnets in an external magnetic field show a rich variety of different ground states meeting in transition lines and multicritical points. We study the dependence of the ground states of these systems in the three dimensional space on physical parameters as exchange, single ion and cubic anisotropy. One identifies four different ground s
Onuttom Narayan, Iraj Saniee
Understanding key structural properties of large scale networks are crucial for analyzing and optimizing their performance, and improving their reliability and security. Here we show that these networks possess a previously unnoticed feature, global curvature, which we argue has a major impact on core congestion: the load at the core of a network with N node
Characterization by a time-frequency method of classical waves propagation in one-dimensional lattice : effects of the dispersion and localized nonlinearities
physics.class-phOlivier Richoux, Claude Depollier, Jean Hardy
This paper presents an application of time-frequency methods to characterize the dispersion of acoustic waves travelling in a one-dimensional periodic or disordered lattice made up of Helmholtz resonators connected to a cylindrical tube. These methods allow (1) to evaluate the velocity of the wave energy when the input signal is an acoustic pulse ; (2) to di
Jian-ping Chen
Recent precision spin-structure data from Jefferson Lab have significantly advanced our knowledge of nucleon structure at low $Q^2$. Results on the neutron spin sum rules and polarizabilities in the low to intermediate $Q^2$ region are presented. The Burkhardt-Cuttingham Sum Rule was verified within experimental uncertainties. When comparing with theoretical
C. Godreche, H. Grandclaude, J. M. Luck
This paper presents a comprehensive analysis of the degree statistics in models for growing networks where new nodes enter one at a time and attach to one earlier node according to a stochastic rule. The models with uniform attachment, linear attachment (the Barabási-Albert model), and generalized preferential attachment with initial attractiveness are succe
Wenwei Zheng, Dagong Fan, Min Feng, ZhisongWang
Conventional kinesin is a homodimeric motor protein that is capable of walking unidirectionally along a cytoskeletal filament. While previous experiments indicated unyielding unidirectionality against an opposing load up to the so-called stall force, recent experiments also observed limited processive backwalking under superstall loads. This theoretical stud
I. Takahashi, M. Kawaharada, K. Makishima, K. Matsushita
X-ray data of the Centaurus cluster, obtained with {\it XMM-Newton} for 45 ksec, were analyzed. Deprojected EPIC spectra from concentric thin shell regions were reproduced equally well by a single-phase plasma emission model, or by a two-phase model developed by {\it ASCA}, both incorporating cool (1.7--2.0 keV) and hot ($\sim 4$ keV) plasma temperatures. Ho
Jian-Zu Zhang
In two-dimensional noncommutive space for the case of both position - position and momentum - momentum noncommuting, the consistent deformed bosonic algebra at the non-perturbation level described by the deformed annihilation and creation operators is investigated. A general relation between noncommutative parameters is fixed from the consistency of the defo
L. S. Dubrovinsky, N. A. Dubrovinskaia, V. Swamy, J. Muscat
Despite great technological importance and many investigations, a material with measured hardness comparable to that of diamond or cubic boron nitride has yet to be identified. Combined theoretical and experimental investigations led to the discovery of a new polymorph of titanium dioxide with titanium nine-coordinated to oxygen in the cotunnite (PbCl2) stru
Ignacio Ferreras, Nick E. Mavromatos, Mairi Sakellariadou, Muhammad Furqaan Yusaf
We constrain the one-parameter class of TeVeS models by testing the theory against both rotation curve and strong gravitational lensing data on galactic scales, remaining fully relativistic in our formalism. The upshot of our analysis is that -- at least in its simplest original form, which is the only one studied in the literature so far -- TeVeS is ruled o
Hiroyuki Hagiwara, Hirohiko Sato, Masahiro Iwaki, Yasuo Narumi
Co$_{4}$B$_{6}$O$_{13}$ contains undistorted tetrahedral clusters of magnetic Co$^{2+}$ ions. The high-field magnetization of this magnet exhibits a periodic undulation indicating quantization of the total spin number per cluster. Measurements of magnetic susceptibility and specific heat reveal that the ground state is composed of several different singlet s
Anderson localization in a two-particle continuous model with an alloy-type external potential
math-phA. Boutet de Monvel, V. Chulaevsky, P. Stollmann, Y. Suhov
We establish exponential localization for a two-particle Anderson model in a Euclidean space ${\mathbb R}^{d}$, $d\ge 1$, in presence of a non-trivial short-range interaction and a random external potential of the alloy type. Specifically, we prove that all eigenfunctions with eigenvalues near the lower edge of the spectrum decay exponentially in $L^2$-norm.
Sergey Neshveyev
We show that the KMS_beta-states of Bost-Connes type systems for number fields in the region 0<beta\le 1, as well as of the Connes-Marcolli GL_2-system for 1<beta\le 2, have type III_1. This is equivalent to ergodicity of various actions on adelic spaces. For example, the case beta=2 of the GL_2-system corresponds to ergodicity of the action of GL_2(Q) on Ma
Is scientific literature subject to a sell-by-date? A general methodology to analyze the durability of scientific documents
physics.soc-phRodrigo Costas, Thed N. van Leeuwen, Anthony F. J. van Raan
The study of the citation histories and ageing of documents are topics that have been addressed from several perspectives, especially in the analysis of documents with delayed recognition or sleeping beauties. However, there is no general methodology that can be extensively applied for different time periods and/or research fields. In this paper a new method
Sensitive detection of photoexcited carriers by resonant tunneling through a single quantum dot
cond-mat.mes-hallE. E. Vdovin, O. Makarovsky, A. Patane, L. Eaves
We show that the resonant tunnel current through a single energy level of an individual quantum dot within an ensemble of dots is strongly sensitive to photoexcited holes that become bound in the close vicinity of the dot. The presence of these holes lowers the electrostatic energy of the quantum dot state and switches the current carrying channel from fully
Detecting Relic Gravitational Waves in the CMB: Comparison of Planck and Ground-based Experiments
astro-ph.COW. Zhao, W. Zhang
We compare the detection abilities for the relic gravitational waves by two kinds of forthcoming cosmic microwave background radiation (CMB) experiments, space-based Planck satellite and the various ground-based experiments. Comparing with the ground-based experiments, Planck satellite can observe all the CMB power spectra in all the multipole range, but hav
Eugen Radu, D. H. Tchrakian
A classification of gravitating Yang--Mills systems in all dimensions is presented. These systems are set up so that they support finite energy solutions. Both regular and black hole solutions are considered, the former being the limit of the latter for vanishing event horizon radius. Special attention is paid to systems necessarily involving higher order Ya