March 2010 arXiv papers — page 42
Showing 4,101–4,200 of 5,984 papers
Characterization of horizontal flows around solar pores from high-resolution time series of images
astro-ph.SRS. Vargas Dominguez, A. de Vicente, J. A. Bonet, V. Martinez Pillet
Though there is increasing evidence linking the moat flow and the Evershed flow along the penumbral filaments, there is not a clear consensus regarding the existence of a moat flow around umbral cores and pores, and the debate is still open. Solar pores appear to be a suitable scenario to test the moat-penumbra relation as evidencing the direct interaction b
J. P. B. C. de Melo, T. Frederico
Electroweak transition form factors of heavy meson decays are important ingredients in the extraction of the Cabibbo-Kobayashi-Maskawa (CKM) matrix elements from experimental data. In this work, within a light-front framework, we calculate electroweak transition form factor for the semileptonic decay of $D$ mesons into a pion or a kaon. The model results und
Andrei Bytsko
The spectral resolution of a U_q(sl_2)-invariant solution R of the constant Yang-Baxter equation in the braid group form is considered. It is shown that, if the two highest coefficients in this resolution are not equal, then R is either the Drinfeld R-matrix or its inverse.
Aaron Lauve, Sarah Mason
We prove that the subset of quasisymmetric polynomials conjectured by Bergeron and Reutenauer to be a basis for the coinvariant space of quasisymmetric polynomials is indeed a basis. This provides the first constructive proof of the Garsia-Wallach result stating that quasisymmetric polynomials form a free module over symmetric polynomials and that the dimens
R. J. J. H. van Son
Attacks on cryptographic systems are limited by the available computational resources. A theoretical understanding of these resource limitations is needed to evaluate the security of cryptographic primitives and procedures. This study uses an Attacker versus Environment game formalism based on computability logic to quantify Shannon's work function and e
Mladen Savov, Matthias Winkel
This article is about right inverses of Levy processes as first introduced by Evans in the symmetric case and later studied systematically by the present authors and their co-authors. Here we add to the existing fluctuation theory an explicit description of the excursion measure away from the (minimal) right inverse. This description unifies known formulas i
Nick Halmagyi
We consider massive IIA supergravity on the resolved conifold with $SU(2)_L^2\times U(1)_R$ symmetry and $\N=1$ supersymmetry. A one dimensional family of such regular solutions was found by Brandhuber and we propose this to be the mirror to one dimension of the moduli space of IIB solutions on the deformed conifold found by Butti et al. This family provides
Attractor and Basin Entropies of Random Boolean Networks Under Asynchronous Stochastic Update
cond-mat.stat-mechAmer Shreim, Andrew Berdahl, Florian Greil, Jörn Davidsen
We introduce a numerical method to study random Boolean networks with asynchronous stochas- tic update. Each node in the network of states starts with equal occupation probability and this probability distribution then evolves to a steady state. Nodes left with finite occupation probability determine the attractors and the sizes of their basins. As for synch
S. Kıntaş, S. Turgut
The transformations of $W$-type entangled states by using local operations assisted with classical communication are investigated. For this purpose, a parametrization of the $W$-type states which remains invariant under local unitary transformations is proposed and a complete characterization of the local operations carried out by a single party is given. Th
Localization and Tensorization Properties of the Curvature-Dimension Condition for Metric Measure Spaces
math.DGKathrin Bacher, Karl-Theodor Sturm
This paper is devoted to the analysis of metric measure spaces satisfying locally the curvature-dimension condition CD(K,N) introduced by the second author and also studied by Lott & Villani. We prove that the local version of CD(K,N) is equivalent to a global condition CD*(K,N), slightly weaker than the (usual, global) curvature-dimension condition. This so
Kathrin Bacher, Karl-Theodor Sturm
We prove generalized lower Ricci bounds for Euclidean and spherical cones over compact Riemannian manifolds. These cones are regarded as complete metric measure spaces. We show that the Euclidean cone over an n-dimensional Riemannian manifold whose Ricci curvature is bounded from below by n-1 satisfies the curvature-dimension condition CD(0,n+1) and that the
Anthony F. J. van Raan, Thed N. van Leeuwen, Martijn S. Visser, Nees Jan van Eck
We reply to the criticism of Opthof and Leydesdorff [arXiv:1002.2769] on the way in which our institute applies journal and field normalizations to citation counts. We point out why we believe most of the criticism is unjustified, but we also indicate where we think Opthof and Leydesdorff raise a valid point.
Microwave driven arbitrary coupling between trapped charge resonances in a silicon single electron transistor
cond-mat.mes-hallMorteza Erfani, David G. Hasko, Alessandro Rossi, Wan Sik Cho
In quantum computation, information is processed by gates that must coherently couple separate qubits. In many systems the qubits are naturally coupled, but such an always-on interaction limits the algorithms that may be implemented. Coupling interactions may also be directed in devices and circuits that are provided with additional control wiring. This can
Hong-Viet V. Ngo, Jan Köhler, Jörg Mayer, Jens Christian Claussen
Slow-wave sleep in mammalians is characterized by a change of large-scale cortical activity currently paraphrased as cortical Up/Down states. A recent experiment demonstrated a bistable collective behaviour in ferret slices, with the remarkable property that the Up states can be switched on and off with pulses, or excitations, of same polarity; whereby the e
Tracking of individual freely diffusing fluorescent protein molecules in the bacterial cytoplasm
q-bio.QMBrian P. English, Arash Sanamrad, Stoyan Tankov, Vasili Hauryliuk
We combine stroboscopic laser excitation with stochastic photoactivation and super-resolution fluorescence imaging. This makes it possible to record hundreds of diffusion trajectories of small protein molecules in single bacterial cells with millisecond time resolution and sub-diffraction limited spatial precision. We conclude that the small protein mEos2 ex
Peter Jossen
Let A be a geometrically simple abelian variety over a number field k, let X be a subgroup of A(k) and let P be an element of A(k). We prove that if P belongs to X modulo almost all primes of k then P already belongs to X.
Oliver C. Schnürer, Felix Schulze, Miles Simon
We study the Ricci flow of initial metrics which are C^0-perturbations of the hyperbolic metric on H^n. If the perturbation is bounded in the L^2-sense, and small enough in the C^0-sense, then we show the following: In dimensions four and higher, the scaled Ricci harmonic map heat flow of such a metric converges smoothly, uniformly and exponentially fast in
M. Cattani
We use the basic equations that predict the emission of gravitational waves according to the Einstein gravitation theory to calculate the luminosities and the amplitudes of the waves generated by binary stars, pulsations of neutron stars, wobbling of deformed neutron stars, oscillating quadrupoles, rotating bars and collapsing and bouncing cores of supernova
Dawei Yang
We prove that for any $C^1$-stably weakly shadowing transitive set $Λ$, either $Λ$ is a sink or a source, or $Λ$ admits a dominated splitting.
Mikhail Skopenkov
Given a cake in form of a triangle and a box that fits the mirror image of the cake, how to cut the cake into a minimal number of pieces so that it can be put into the box? The cake has an icing, so that we are not allowed to put it into the box upside down. V.G. Boltyansky asked this question in 1977 and showed that three pieces always suffice. In this pape
Ruy Exel, Astrid an Huef, Iain Raeburn
Given an n x n integer matrix A whose eigenvalues are strictly greater than 1 in absolute value, let σ_A be the transformation of the n-torus T^n=R^n/Z^n defined by σ_A(e^{2πix})=e^{2πiAx} for x\in R^n. We study the associated crossed-product C*-algebra, which is defined using a certain transfer operator for σ_A, proving it to be simple and purely infinite a
Anders Kock
The projective line over a field carries structure of a groupoid with a certain correspondence between objects and arrows. We discuss to what extent the field can be reconstructed from the groupoid.
J. P. Coe, I. D'Amico
In this chapter we discuss methods to calculate the entanglement of a system using density-functional theory. We firstly introduce density-functional theory and the local-density approximation (LDA). We then discuss the concept of the `interacting LDA system'. This is characterised by an interacting many-body Hamiltonian which reproduces, uniquely and ex
Jörg Lehmann, Jakob Bernasconi
We study fracture processes within a stochastic fiber-bundle model where it is assumed that after the failure of a fiber, each intact fiber obtains a random fraction of the failing load. Within a Markov approximation, the breakdown properties of this model can be reduced to the solution of an integral equation. As examples we consider two different versions
Effective time-reversal symmetry breaking in the spin relaxation in a graphene quantum dot
cond-mat.mes-hallP. R. Struck, Guido Burkard
We study the relaxation of a single electron spin in a circular gate-tunbable quantum dot in gapped graphene. Direct coupling of the electron spin to out-of-plane phonons via the intrinsic spin-orbit coupling leads to a relaxation time T_1 which is independent of the B-field at low fields. We also find that Rashba spin-orbit induced admixture of opposite spi
Gabriela Barreto Lemos, Giuliano Benenti
In this article we treat the subject of chaotic environments with few degrees of freedom in quantum communication by investigating a conservative dynamical map as a model of a dephasing quantum channel. When the channel's dynamics is chaotic, we investigate the model's semi-classical limit and show that the entropy exchange grows at a constant rate w
Joost Melai, Amos Breskin, Marco Cortesi, Yevgen Bilevych
This article presents a detector system consisting of three components, a CMOS imaging array, a gaseous-detector structure with a Micromegas layout and a UV-photon sensitive CsI reflective photocathode. All three elements have been monolithically integrated using simple post-processing steps. The Micromegas structure and the CMOS imaging chip are not impacte
Evidence for triplet superconductivity in Josephson junctions with ferromagnetic Cu$_{2}$MnAl-Heusler barriers
cond-mat.supr-conD. Sprungmann, K. Westerholt, H. Zabel, M. Weides
We have studied Josephson junctions with barriers prepared from the Heusler compound Cu$_2$MnAl. In the as-prepared state the Cu$_2$MnAl layers are non ferromagnetic and the critical Josephson current density $j_{c}$ decreases exponentially with the thickness of the Heusler layers $d_{F}$. On annealing the junctions at 240\degree C the Heusler layers develop
Tyler Foster
In this note, we construct and study an algebraic system similar to the natural numbers, but with noncommutative addition. The addition we introduce is a binary operation that commutes with itself in the sense of N. Durov. Neverheless, the multiplication in this system (defined by iterating the noncommutative addition) turns out to be associative, commutativ
C. C. Chou, C. L. Huang, S. Mukherjee, Q. Y. Chen
The magnetic phase variations under hydrostatic pressure on multiferroic BiMnO3 have been examined by the dc magnetization [Mg(T)], magnetic hysteresis [Ueff(H)], and ac susceptibility [X'g(T)]. Three magnetic transitions, manifested as kinks I, II, and III on the Mg(T)], curves, were identified at 8.7 and 9.4 kbar. With increasing pressure, transition t
Absence of charge-density-wave sliding in epitaxial charge-ordered Pr0.48Ca0.52MnO3 films
cond-mat.str-elB. Fisher, J. Genossar, L. Patlagan, S. Kar-Narayan
For an epitaxial Pr0.48Ca0.52MnO3 film on NdGaO3, we use transmission electron microscopy to observe a "charge-ordered" superlattice along the in-plane direction a. The same film shows no electrical signatures of charge order. The in-plane electrical anisotropy (rho)a/(rho)c = 28 is constant, and there is no evidence of sliding charge density waves u
Valerio Capraro
In a very celebrated paper A. Connes has formulated a conjecture which is now one of the most important open problem in Operator Algebras. This importance comes from the works of many mathematicians who have found some unexpected equivalent statements showing as this conjecture is transversal to almost all the sub-specialization of Operator Algebras. In this
A. Es-Sarhir, M. -K. von Renesse
We study a model of the motion by mean curvature of an (1+1) dimensional interface in a 2D Brownian velocity field. For the well-posedness of the model we prove existence and uniqueness for certain degenerate nonlinear stochastic evolution equations in the variational framework of Krylov Rozovskii, replacing the standard coercivity assumption by a Lyapunov t
Simulation of 4d N=1 supersymmetric Yang-Mills theory with Symanzik improved gauge action and stout smearing
hep-latK. Demmouche, F. Farchioni, A. Ferling, I. Montvay
We report on the results of a numerical simulation concerning the low-lying spectrum of four-dimensional N=1 SU(2) Supersymmetric Yang-Mills (SYM) theory on the lattice with light dynamical gluinos. In the gauge sector the tree-level Symanzik improved gauge action is used, while we use the Wilson formulation in the fermion sector with stout smearing of the g
Current-voltage characteristics of graphene devices: interplay between Zener-Klein tunneling and defects
cond-mat.mtrl-sciNiels Vandecasteele, Amelia Barreiro, Michele Lazzeri, Adrian Bachtold
We report a theoretical/experimental study of current-voltage characteristics (I-V) of graphene devices near the Dirac point. The I-V can be described by a power law (I \propto V^α, with 1< α<= 1.5). The exponent is higher when the mobility is lower. This superlinear I-V is interpreted in terms of the interplay between Zener-Klein transport, that is tunnelin
M. Gupta, A. Gupta, R. Gupta, J. Stahn
Fe and N self-diffusion in non-magnetic FeN has been studied using neutron reflectivity. The isotope labelled multilayers, FeN/57Fe:N and Fe:N/Fe:15N were prepared using magnetron sputtering. It was remarkable to observe that N diffusion was slower compared to Fe while the atomic size of Fe is larger compared to N. An attempt has been made to understand the
C. C. Chou, S. Taran, J. L. Her, C. P. Sun
We report the magnetic field dependent dc magnetization and the pressure-dependent (pmax ~ 16 kbar) ac susceptibilities Xp(T) on both powder and bulk multiferroic BiMnO3 samples, synthesized in different batches under high pressure. A clear ferromagnetic (FM) transition is observed at TC ~ 100 K, and increases with magnetic field. The magnetic hysteresis beh
L. Neslusan
On the basis of general relativity and quantum statistics, it was shown (Neslušan L.: 2009, Phys. Rev. D 80, 024015, arxiv:0808.3484) that the equation of state (ES) of extremely hot Fermi-Dirac gas in the surface layer of an ultra-relativistic compact object converges to the same form as the relativistic equation of thermodynamical equilibrium (RETE), which
Covariant Constitutive Relations, Landau Damping and Non-stationary Inhomogeneous Plasmas
physics.plasm-phJonathan Gratus, Robin W Tucker
Models of covariant linear electromagnetic constitutive relations are formulated that have wide applicability to the computation of susceptibility tensors for dispersive and inhomogeneous media. A perturbative framework is used to derive a linear constitutive relation for a globally neutral plasma enabling one to describe in this context a generalized Landau
Diego Kienle, Mani Vaidyanathan, François Léonard
We develop an approach for self-consistent ac quantum transport in the presence of time-dependent potentials at non-transport terminals. We apply the approach to calculate the high-frequency characteristics of a nanotube transistor with the ac signal applied at the gate terminal. We show that the self-consistent feedback between the ac charge and potential i
Gaussian Curvature estimates for the convex level sets of solutions for some nonlinear elliptic partial differential equations
math.APPei-He Wang, Wei Zhang
We give a lower bound for the Gaussian curvature of convex level sets of minimal graphs and the solutions to semilinear elliptic equations with the norm of boundary gradient and the Gaussian curvature of the boundary.
Francesca D'Antona, Vittoria Caloi, Paolo Ventura
Core helium burning is the dominant source of energy of extreme horizontal branch stars, as the hydrogen envelope is too small to contribute to the nuclear energy output. The evolution of each mass in the HR diagram occurs along vertical tracks that, when the core helium is consumed, evolve to higher Teff and then to the white dwarf stage. The larger is the
A connection with parallel totally skew-symmetric torsion on a class of almost hypercomplex manifolds with Hermitian and anti-Hermitian metrics
math.DGMancho Manev, Kostadin Gribachev
The subject of investigations are the almost hypercomplex manifolds with Hermitian and anti-Hermitian (Norden) metrics. A linear connection D is introduced such that the structure of these manifolds is parallel with respect to D and its torsion is totally skew-symmetric. The class of the nearly Kaehler manifolds with respect to the first almost complex struc
Radja Boughezal, Frank Petriello
We compute the next-to-next-to-leading order QCD corrections to the gluon-fusion production of a Higgs boson in models with massive color-octet scalars in the ${\bf (8,1)_0}$ representation using an effective-theory approach. We derive a compact analytic expression for the relevant Wilson coefficient, and explain an interesting technical aspect of the calcul
Mehmet Önder, Hüseyin Kocayiğit, Mustafa Kazaz
In this paper, we give the characterizations of spacelike B2-slant helix by means of curvatures of the spacelike curve in Minkowski 4-space. Furthermore, we give the integral characterization of the spacelike B2-slant helix.
Electronic Structure Calculations of Magnetic Exchange Interactions in Europium Monochalcogenides
cond-mat.mtrl-sciXiangang Wan, Jinming Dong, Sergej Y. Savrasov
Using a combination of local spin density and Hubbard 1 approximations we study the mechansim of exchange interacion in EuX (X=O, S, Se and Te). We reproduce known experimental results about bulk modulus, critical pressure for structural phase transition, magnetic ordering temperature, spin--wave dispersions as well as momentum-- and tempearuture--dependent
Quantum Phase Transition in Coupled Superconducting Quantum Dots Array with Charge Frustration
cond-mat.mes-hallSujit Sarkar
We present the quantum phase transition in two capacitively coupled arrays of superconducting quantum dots (SQD). We consider the presence of gate voltage in each superconducting island. We show explicitly that the co-tunneling process involves with two coupled SQD arrays, near the maximum charge frustration line is not sufficient to explain the correct quan
L. Shvedov, M. Colonna, M. Di Toro
We investigate reaction mechanisms occurring in heavy ion collisions at low energy (around 20 MeV/u). In particular, we focus on the competition between fusion and break-up processes (Deep-Inelastic and fragmentation) in semi-peripheral collisions, where the formation of excited systems in various conditions of shape and angular momentum is observed. Adoptin
Crumpling transition of the triangular lattice without open edges: effect of a modified folding rule
cond-mat.stat-mechYoshihiro Nishiyama
Folding of the triangular lattice in a discrete three-dimensional space is investigated by means of the transfer-matrix method. This model was introduced by Bowick and co-workers as a discretized version of the polymerized membrane in thermal equilibrium. The folding rule (constraint) is incompatible with the periodic-boundary condition, and the simulation h
Gautam I. Menon
The term active matter describes diverse systems, spanning macroscopic (e.g. shoals of fish and flocks of birds) to microscopic scales (e.g. migrating cells, motile bacteria and gels formed through the interaction of nanoscale molecular motors with cytoskeletal filaments within cells). Such systems are often idealizable in terms of collections of individual
Mahito Sasada, Makoto Uemura, Akira Arai, Yasushi Fukazawa
We report on optical-near-infrared photopolarimetric observations of a blazar 3C 454.3 over 200 d. The object experienced an optical outburst in July 2007. This outburst was followed by a short state fainter than $V=15.2$ mag lasting $\sim 25$ d. The object, then, entered an active state during which we observed short flares having a timescale of 3-10 d. The
The STAR Collaboration, B. I. Abelev
Nuclear collisions recreate conditions in the universe microseconds after the Big Bang. Only a very small fraction of the emitted fragments are light nuclei, but these states are of fundamental interest. We report the observation of antihypertritons - composed of an antiproton, antineutron, and antilambda hyperon - produced by colliding gold nuclei at high e
Yasuhiro Yamaguchi, Takaaki Sogo, Toru Ito, Takahiko Miyakawa
We consider a uniform dipolar Fermi gas in two-dimensions (2D) where the dipole moments of fermions are aligned by an orientable external field. We obtain the ground state of the gas in Hartree-Fock approximation and investigate RPA stability against density fluctuations of finite momentum. It is shown that the density wave instability takes place in a broad
Francesco Barioli, Wayne Barrett, Shaun M. Fallat, H. Tracy Hall
The zero forcing number Z(G), which is the minimum number of vertices in a zero forcing set of a graph G, is used to study the maximum nullity / minimum rank of the family of symmetric matrices described by G. It is shown that for a connected graph of order at least two, no vertex is in every zero forcing set. The positive semidefinite zero forcing number Z_
Zachary Mesyan
Let X be a countably infinite set, and let f, g, and h be any three injective self-maps of X, each having at least one infinite cycle. (For instance, this holds if f, g, and h are not bijections.) We show that there are permutations a and b of X such that h=afa^{-1}bgb^{-1} if and only if |X\Xf|+|X\Xg|=|X\Xh|. We also prove a version of this statement that h
Diffuse Neutron Scattering Study of Magnetic Correlations in half-doped La0.5Ca0.5-xSrxMnO3 (x = 0.1, 0.3 and 0.4) Manganites
cond-mat.mtrl-sciI. Dhiman, A. Das, R. Mittal, Y. Su
The short range ordered magnetic correlations have been studied in half doped La0.5Ca0.5-xSrxMnO3 (x = 0.1, 0.3 and 0.4) compounds by polarized neutron scattering technique. On doping Sr2+ for Ca2+ ion, these compounds with x = 0.1, 0.3, and 0.4 exhibit CE-type, mixture of CE-type and A-type, and A-type antiferromagnetic ordering, respectively. Magnetic diff
Xueda Wen, Yiwen Wang, Shanhua Cong, Guozhu Sun
Landau-Zener-Stuckelberg interferometry has been extensively investigated in quantum two-level systems, with particular interests on artificial system such as superconducting flux qubits. With increasing the driving field amplitude, more energy levels will be involved into the quantum evolution, which results in population inversion and many interesting inte
Pressure effects on the magnetic structure in La0.5Ca0.5-xSrxMnO3 (0.1 -< x -< 0.4) manganites
cond-mat.mtrl-sciIndu Dhiman, Thierry Strässle, L. Keller, B. Padmanabhan
The effect of high pressure (0 - 8 GPa) on the magnetic structure of polycrystalline samples of La0.5Ca0.5-xSrxMnO3 (0.1 -< x -< 0.4) manganites at 5 K is investigated using neutron diffraction technique. Application of pressure is found to modify the previously reported magnetic structure, observed under ambient conditions, in these compounds [I. Dhiman et
Guozhu Sun, Xueda Wen, Yiwen Wang, Shanhua Cong
Microwave resonances between discrete macroscopically distinct quantum states with single photon and multiphoton absorption are observed in a strongly driven radio frequency superconducting quantum interference device flux qubit. The amplitude of the resonant peaks and dips are modulated by the power of the applied microwave irradiation and a population inve
Marcella Grasso, Danilo Gambacurta, Francesco Catara
We derive the expression for the residual interaction to be used in the framework of the Second RPA with density-dependent forces. The adopted procedure is based on a variational approach. It is found that the residual interaction to be used in RPA and beyond RPA matrix elements is not the same as far as the rearrangement terms are concerned. A detailed deri
Bilinear Equations and Bäcklund Transformation for Generalized Ultradiscrete Soliton Solution
nlin.SIHidetomo Nagai, Daisuke Takahashi
Ultradiscrete soliton equations and Bäcklund transformation for a generalized soliton solution are presented. The equations include the ultradiscrete KdV equation or the ultradiscrete Toda equation in a special case. We also express the solution by the ultradiscrete permanent, which is defined by ultradiscretizing the signature-free determinant, that is, the
James Z. M. Gao, Linda Y. M. Li, Christian M. Reidys
Background: RNA exhibits a variety of structural configurations. Here we consider a structure to be tantamount to the noncrossing Watson-Crick and \pairGU-base pairings (secondary structure) and additional cross-serial base pairs. These interactions are called pseudoknots and are observed across the whole spectrum of RNA functionalities. In the context of st
Johan Brannlund, Robert van den Hoogen, Alan Coley
We construct a framework within which a mathematically precise, fully covariant, and exact averaging procedure for tensor fields on a manifold can be formulated. In particular, we introduce the Weitzenböck connection for parallel transport and argue that, within the context of averaging, frames and connections are the natural geometrical objects on the manif
Wolfgang Steffen, Nicholas Koning, Stephan Wenger, Christophe Morisset
We present a flexible interactive 3D morpho-kinematical modeling application for astrophysics. Compared to other systems, our application reduces the restrictions on the physical assumptions, data type and amount that is required for a reconstruction of an object's morphology. It is one of the first publicly available tools to apply interactive graphics
F. C. Lombardo, F. D. Mazzitelli, P. I. Villar
We discuss new approaches to compute numerically the Casimir interaction energy for waveguides of arbitrary section, based on the boundary methods traditionally used to compute eigenvalues of the 2D Helmholtz equation. These methods are combined with the Cauchy's theorem in order to perform the sum over modes. As an illustration, we describe a point-matc
S. V. Astashkin, D. V. Zanin, E. M. Semenov, F. A. Sukochev
The Kruglov property and the Kruglov operator play an important role in the study of geometric properties of r.i. function spaces. We prove that the boundedness of the Kruglov operator in a r.i. space is equivalent to the uniform boundedness on this space of a sequence of operators defined by random permutations. It is shown also that there is no minimal r.i
Ion Garate, M. Franz
We derive compact analytical expressions for the coupled spin-charge susceptibility of a clean helical metal at the surface of a three dimensional topological insulator (TI). These expressions lead to unconventional non-collinear RKKY interactions between two impurity magnetic moments placed on the surface of a TI, and predict the generation of electric curr
L. Tian
Superconducting qubits connected in an array can form quantum many-body systems such as the quantum Ising model. By coupling the qubits to a superconducting resonator, the combined system forms a circuit QED system. Here, we study the nonlinear behavior in the many-body state of the qubit array using a semiclassical approach. We show that sudden switchings a
Discovery of a superluminal Fe K echo at the Galactic Center: The glorious past of Sgr A* preserved by molecular clouds
astro-ph.HEGabriele Ponti, Regis Terrier, Andrea Goldwurm, Guillaume Belanger
We present the result of a study of the X-ray emission from the Galactic Centre (GC) Molecular Clouds (MC) within 15 arcmin from Sgr A*. We use XMM-Newton data (about 1.2 Ms of observation time) spanning about 8 years. The MC spectra show all the features characteristic of reflection: i) intense Fe Kalpha, with EW of about 0.7-1 keV, and the associated Kbeta
Felix Lindner, René L. Schilling
Considering a linear parabolic stochastic partial differential equation driven by impulsive space time noise, dX_t+AX_t dt= Q^{1/2}dZ_t, X_0=x_0\in H, t\in [0,T], we approximate the distribution of X_T. (Z_t)_{t\in[0,T]} is an impulsive cylindrical process and Q describes the spatial covariance structure of the noise; Tr(A^{-α})<\infty for some α>0 and A^βQ
Run-and-tumble particles with hydrodynamics: sedimentation, trapping and upstream swimming
cond-mat.stat-mechR. W. Nash, R. Adhikari, J. Tailleur, M. E. Cates
We simulate by lattice Boltzmann the nonequilibrium steady states of run-and-tumble particles (inspired by a minimal model of bacteria), interacting by far-field hydrodynamics, subject to confinement. Under gravity, hydrodynamic interactions barely perturb the steady state found without them, but for particles in a harmonic trap such a state is quite changed
Alexandru E. Stanculescu
The category of small 2-categories has two monoidal structures due to John Gray: one biclosed and one closed. We propose a formalisation of the construction of the right internal and internal homs of these monoidal structures.
Minghui Jiang
Given two genomes with duplicate genes, \textsc{Zero Exemplar Distance} is the problem of deciding whether the two genomes can be reduced to the same genome without duplicate genes by deleting all but one copy of each gene in each genome. Blin, Fertin, Sikora, and Vialette recently proved that \textsc{Zero Exemplar Distance} for monochromosomal genomes is NP
More than two equally probable variants of signal in Kauffman networks as an important overlooked case, negative feedbacks allow life in chaos
cond-mat.dis-nnAndrzej Gecow
There are three main aims of this paper. 1- I explain reasons why I await life to lie significantly deeper in chaos than Kauffman approach does, however still in boundary area near `the edge of chaos and order'. The role of negative feedbacks in stability of living objects is main of those reasons. In Kauffman's approach regulation using negative fee
T. C. Ralph, C. R. Myers
Recently, the quantum information processing power of closed timelike curves have been discussed. Because the most widely accepted model for quantum closed timelike curve interactions contains ambiguities, different authors have been able to reach radically different conclusions as to the power of such interactions. By tracing the information flow through su
Kevin T. Engel
We present a new type of brane inflation motivated by multi-kink solitonic solutions of a scalar field in five dimensions. In the thin brane limit, we analyze a non-static configuration in which the distance between two parallel domain walls decreases. We show that the ensuing spacetime is inflationary, both on the branes, and, for certain potentials, in the
Microwave-assisted transport via localized states in degenerately doped Si single electron transistors
cond-mat.mes-hallA. Rossi, D. G. Hasko
Resonant microwave-assisted and DC transport are investigated in degenerately doped silicon single electron transistors. A model based on hopping via localized impurity states is developed and first used to explain both the DC temperature dependence and the AC response. In particular, the non-monotonic power dependence of the resonant current under irradiati
Stability of exfoliated Bi$_2$Sr$_2$Dy$_x$Ca$_{1-x}$Cu$_2$O$_{8+δ}$ studied by Raman microscopy
cond-mat.supr-conL. J. Sandilands, J. X. Shen, G. M. Chugunov, F. Zhao
Nanometer thick cuprates are an appealing platform for devices as well as exploring the roles of dimensionality, disorder, and free carrier density in these compounds. To this end we have produced exfoliated crystals of Bi2Sr2CaCu2O8 on oxidized silicon substrates. The exfoliated crystals were characterized via Atomic Force and polarized Raman microscopies.
Brett Parker
This paper extends de Rham theory of smooth manifolds to exploded manifolds. Included are versions of Stokes' theorem, De Rham cohomology, Poincare duality, and integration along the fiber. The resulting cohomology theory is used to define Gromov Witten invariants of exploded manifolds in a separate paper.
Brian A. Ruzicka, Lalani K. Werake, Hui Zhao, Shuai Wang
The dynamics of photocarriers in reduced graphene oxide thin films is studied by using ultrafast pump-probe spectroscopy. Time dependent differential transmissions are measured with sample temperatures ranging from 9 to 300 K. At each sample temperature and probe delay, the sign of differential transmission remains positive. A fast energy relaxation of hot c
G. L. Cardoso, B. de Wit, S. Mahapatra
The Hesse potential is constructed for a class of four-dimensional N=2 supersymmetric effective actions with S- and T-duality by performing the relevant Legendre transform by iteration. It is a function of fields that transform under duality according to an arithmetic subgroup of the classical dualities reflecting the monodromies of the underlying string com
Shmuel Friedland
We study tensors in $\C^{m\times n\times l}$ whose border rank is $l$. We characterize the tensors in $\C^{3\times 3\times 4}$ and in $\C^{4\times 4\times 4}$ of border rank 4 at most.
Ying Ran, Pavan Hosur, Ashvin Vishwanath
A central theme in many body physics is emergence - new properties arise when several particles are brought together. Particularly fascinating is the idea that the quantum statistics may be an emergent property. This was first noted in the Skyrme model of nuclear matter, where a theory formulated entirely in terms of a bosonic order parameter field contains
Multiple scattering of ultrasound in weakly inhomogeneous media: application to human soft tissues
physics.class-phAlexandre Aubry, Arnaud Derode
Waves scattered by a weakly inhomogeneous random medium contain a predominant single scattering contribution as well as a multiple scattering contribution which is usually neglected, especially for imaging purposes. A method based on random matrix theory is proposed to separate the single and multiple scattering contributions. The experimental set up uses an
F. M. Day, Y. M. Pihlstrom, M. J. Claussen, R. Sahai
We report on the results of two epochs of Very Long Baseline Array (VLBA) observations of the 22 GHz water masers toward IRAS 19190+1102. The water maser emission from this object shows two main arc-shaped formations perpendicular to their NE-SW separation axis. The arcs are separated by ~280 mas in position, and are expanding outwards at an angular rate of
Christian S. Fischer, Axel Maas, Jens A. Mueller
We study a gauge invariant order parameter for deconfinement and the chiral condensate in SU(2) and SU(3) Yang-Mills theory in the vicinity of the deconfinement phase transition using the Landau gauge quark and gluon propagators. We determine the gluon propagator from lattice calculations and the quark propagator from its Dyson-Schwinger equation, using the
Estimation of Rényi Entropy and Mutual Information Based on Generalized Nearest-Neighbor Graphs
stat.MLDávid Pál, Barnabás Póczos, Csaba Szepesvári
We present simple and computationally efficient nonparametric estimators of Rényi entropy and mutual information based on an i.i.d. sample drawn from an unknown, absolutely continuous distribution over $\R^d$. The estimators are calculated as the sum of $p$-th powers of the Euclidean lengths of the edges of the `generalized nearest-neighbor' graph of the
Joseph Levy
Assuming the existence of a preferred aether frame and the anisotropy of the one-way speed of light in platforms different from the aether frame, we derive the space and time transformations relative to bodies moving in any direction of space and not only in the direction of the common x-axis of the co-ordinate systems under consideration. Taking for granted
Andrew Ledoan, Marco Merkli, Shannon Starr
We consider random analytic functions defined on the unit disk of the complex plane as power series such that the coefficients are i.i.d., complex valued random variables, with mean zero and unit variance. For the case of complex Gaussian coefficients, Peres and Virág showed that the zero set forms a determinantal point process with the Bergman kernel. We sh
An Axiomatic Setup for Algorithmic Homological Algebra and an Alternative Approach to Localization
math.ACMohamed Barakat, Markus Lange-Hegermann
In this paper we develop an axiomatic setup for algorithmic homological algebra of Abelian categories. This is done by exhibiting all existential quantifiers entering the definition of an Abelian category, which for the sake of computability need to be turned into constructive ones. We do this explicitly for the often-studied example Abelian category of fini
Gavin D. Scott, Douglas Natelson
Molecular electronic devices currently serve as a platform for studying a variety of physical phenomena only accessible at the nanometer scale. One such phenomenon is the highly correlated electronic state responsible for the Kondo effect, manifested here as a "Kondo resonance" in the conductance. Because the Kondo effect results from strong electron
Tuning Fermilab Heavy Quarks in 2+1 Flavor Lattice QCD with Application to Hyperfine Splittings
hep-latC. Bernard, C. DeTar, M. Di Pierro, A. X. El-Khadra
We report the non-perturbative tuning of parameters--- kappa_c, kappa_b, and kappa_crit ---that determine the heavy-quark mass in the Fermilab action. This requires the computation of the masses of Ds^(*) and Bs^(*) mesons comprised of a Fermilab heavy quark and a staggered light quark. Additionally, we report the hyperfine splittings for Ds and Bs mesons as
Phonon switching and combined Fano-Rice effect in optical spectra of bilayer graphene
cond-mat.str-elE. Cappelluti, L. Benfatto, A. B. Kuzmenko
Recent infrared measurements of phonon peaks in gated bilayer graphene reveal two striking signatures of electron-phonon interaction: an asymmetric Fano lineshape and a giant variation of the peak intensity as a function of the applied gate voltage. In this Letter we provide a unified theoretical framework which accounts for both these effects and unveils th
Quantum spin chains of Temperley-Lieb type: periodic boundary conditions, spectral multiplicities and finite temperature
cond-mat.stat-mechBritta Aufgebauer, Andreas Kluemper
We determine the spectra of a class of quantum spin chains of Temperley-Lieb type by utilizing the concept of Temperley-Lieb equivalence with the S=1/2 XXZ chain as a reference system. We consider open boundary conditions and in particular periodic boundary conditions. For both types of boundaries the identification with XXZ spectra is performed within isomo
J. Martin-Camalich, L. S. Geng, M. J. Vicente Vacas
We present an analysis of the baryon-octet and -decuplet masses using covariant SU(3)-flavor chiral perturbation theory up to next-to-leading order. Besides the description of the physical masses we address the problem of the lattice QCD extrapolation. Using the PACS-CS collaboration data we show that a good description of the lattice points can be achieved
Exponential convergence for a convexifying equation and a non-autonomous gradient flow for global minimization
math.APGuillaume Carlier, Alfred Galichon
We consider an evolution equation similar to that introduced by Vese and whose solution converges in large time to the convex envelope of the initial datum. We give a stochastic control representation for the solution from which we deduce, under quite general assumptions that the convergence in the Lipschitz norm is in fact exponential in time. We then intro
O. J. Lipscombe, Leland W. Harriger, P. G. Freeman, M. Enderle
We use polarized inelastic neutron scattering to show that the neutron spin resonance below $T_c$ in superconducting BaFe$_{1.9}$Ni$_{0.1}$As$_2$ ($T_c=20$ K) is purely magnetic in origin. Our analysis further reveals that the resonance peak near 7~meV only occurs for the planar response. This challenges the common perception that the spin resonance in the p
D. Perna, E. Dotto, M. Lazzarin, S. Magrin
CONTEXT: In July 2010 the ESA spacecraft Rosetta will fly-by the main belt asteroid 21 Lutetia. Several observations of this asteroid have been so far performed, but its surface composition and nature are still a matter of debate. For long time Lutetia was supposed to have a metallic nature due to its high IRAS albedo. Later on it has been suggested to have
Thomas Dedieu, Fabio Perroni
We prove a structure theorem for the fundamental group of the quotient $X$ of a product of curves by the action of a finite group $G$, hence for that of any resolution of the singularities of $X$.
Alain Bruguières, Steve Lack, Alexis Virelizier
We define Hopf monads on an arbitrary monoidal category, extending the definition given previously for monoidal categories with duals. A Hopf monad is a bimonad (or opmonoidal monad) whose fusion operators are invertible. This definition can be formulated in terms of Hopf adjunctions, which are comonoidal adjunctions with an invertibility condition. On a mon