April 2010 arXiv papers — page 18
Showing 1,701–1,800 of 5,597 papers
Vitaly Osipov, Peter Sanders
We present a multi-level graph partitioning algorithm based on the extreme idea to contract only a single edge on each level of the hierarchy. This obviates the need for a matching algorithm and promises very good partitioning quality since there are very few changes between two levels. Using an efficient data structure and new flexible ways to break local s
Diego Luis Gonzalez Cabrera, Zoltan Racz, Frederic van Wijland
We present a fully microscopics-based calculation of the Casimir effect in a nonequilibrium system, namely an energy flux driven quantum XX chain. The force between the walls (transverse-field impurities) is calculated in a nonequilibrium steady state which is prepared by letting the system evolve from an initial state with the two halves of the chain prepar
Paul Lesov
The importance of security in database research has greatly increased over the years as most of critical functionality of the business and military enterprises became digitized. Database is an integral part of any information system and they often hold sensitive data. The security of the data depends on physical security, OS security and DBMS security. Datab
Grzegorz Karch, Kanako Suzuki
A class of nonlinear viscous transport equations describing aggregation phenomena in biology is considered. Optimal conditions on an interaction potential are obtained which lead either to the existence or to the nonexistence of global-in-time solutions.
Gottfried Lechner, Troels Pedersen, Gerhard Kramer
Binary message-passing decoders for low-density parity-check (LDPC) codes are studied by using extrinsic information transfer (EXIT) charts. The channel delivers hard or soft decisions and the variable node decoder performs all computations in the L-value domain. A hard decision channel results in the well-know Gallager B algorithm, and increasing the output
Richard Oberlin, Christoph Thiele
We prove old and new $L^p$ bounds for the quartile operator, a Walsh model of the bilinear Hilbert transform, uniformly in the parameter that models degeneration of the bilinear Hilbert transform. We obtain the full range of exponents that can be expected from known bounds in the degenerate and non-degenerate cases. For the new estimates with exponents p clo
Hubert L. Bray
Beginning with a geometric motivation for dark matter going back to the axioms of general relativity, we show how scalar field dark matter, which naturally forms dark matter density waves due to its wave nature, may cause the observed barred spiral pattern density waves in many disk galaxies and triaxial shapes with plausible brightness profiles in many elli
Nader Masmoudi
Systems coupling fluids and polymers are of great interest in many branches of sciences. One of the models to describe them is the FENE (Finite Extensible Nonlinear Elastic) dumbbell model. We prove global existence of weak solutions to the FENE dumbbell model of polymeric flows for a very general class of potentials. The main problem is the passage to the l
Estimates for the Spectral Condition Number of Cardinal B-Spline Collocation Matrices (Long version)
math.NAVedran Novakovic, Sanja Singer, Sasa Singer
The famous de Boor conjecture states that the condition of the polynomial B-spline collocation matrix at the knot averages is bounded independently of the knot sequence, i.e., depends only on the spline degree. For highly nonuniform knot meshes, like geometric meshes, the conjecture is known to be false. As an effort towards finding an answer for uniform mes
Doowon Koh, Chun-Yen Shen
In this paper we study the generalized Erdos-Falconer distance problems in the finite field setting. The generalized distances are defined in terms of polynomials, and various formulas for sizes of distance sets are obtained. In particular, we develop a simple formula for estimating the cardinality of distance sets determined by diagonal polynomials. As a re
Antonio Laface, Luca Ugaglia
We study conjectures on the dimension of linear systems on the blow-up of P^2 and P^3 at points in very general position. We provide algorithms and Maple codes based on these conjectures.
V. K. Sangwan, A. Behnam, V. W. Ballarotto, M. S. Fuhrer
In percolating networks of mixed metallic and semiconducting CNTs, there is a tradeoff between high on-current (dense networks) and high on/off ratio (sparse networks in which the metallic CNT fraction is not percolating). Experiments on devices in a transistor configuration and Monte Carlo simulations were performed to determine the scaling behavior of devi
M. T. Thomaz, A. C. Aguiar Pinto, M. Moutinho
We present the time evolution of the electronic two-level model in the rotating wave approximation (RWA). We calculate the Aharonov-Anandan phase of the vector states with cyclic evolution either within the period of an external monochromatic electric field or the period corresponding to Rabi's frequency. The Aharonov-Anandan phase is shown to be depende
C. J. Salter, D. J. Saikia, R. Minchin, T. Ghosh
We report the discovery of HI 21-cm absorption towards the well-studied GHz Peaked-Spectrum source CTA 21 (4C 16.09) using the Arecibo Telescope on 2009 September 20 and 21. Recently, the frequency band between 700 and 800 MHz was temporarily opened up to radio astronomy when US TV stations were mandated to switch from analog to digital transmissions, with n
Thomas Eggel, Masaki Oshikawa, Keiya Shirahama
The superfluid transition in liquid 4He filled in Gelsil glass observed in recent experiments is discussed in the framework of quantum critical phenomena. We show that quantum fluctuations of phase are indeed important at the experimentally studied temperature range owing to the small pore size of Gelsil, in contrast to 4He filled in previously studied porou
John J. Bochanski, Suzanne L. Hawley, Kevin R. Covey, Andrew A. West
We report on new measurements of the luminosity function (LF) and mass function (MF) of field low-mass dwarfs derived from Sloan Digital Sky Survey (SDSS) Data Release 6 (DR6) photometry. The analysis incorporates ~15 million low-mass stars (0.1 Msun < M < 0.8 Msun), spread over 8,400 square degrees. Stellar distances are estimated using new photometric para
HD 101088, An Accreting 14 AU Binary in Lower Centaurus Crux With Very Little Circumstellar Dust
astro-ph.SRMartin A. Bitner, Christine H. Chen, James Muzerolle, Alycia J. Weinberger
We present high resolution (R=55,000) optical spectra obtained with MIKE on the 6.5 m Magellan Clay Telescope as well as Spitzer MIPS photometry and IRS low resolution (R~60) spectroscopy of the close (14 AU separation) binary, HD 101088, a member of the ~12 Myr old southern region of the Lower Centaurus Crux (LCC) subgroup of the Scorpius-Centaurus OB assoc
Clemens P. Kiessig, Markus H. Thoma, Michael Pluemacher
We calculate the decay rate of the lightest heavy Majorana neutrino in a thermal bath using finite temperature cutting rules and effective Green's functions according to the hard thermal loop resummation technique. Compared to the usual approach where thermal masses are inserted into the kinematics of final states, we find that deviations arise through t
The San Pedro Mártir Planetary Nebula Kinematic Catalogue: Extragalactic Planetary Nebulae
astro-ph.SRM. G. Richer, J. A. López, E. Díaz-Méndez, H. Riesgo
We present kinematic data for 211 bright planetary nebulae in eleven Local Group galaxies: M31 (137 PNe), M32 (13), M33 (33), Fornax (1), Sagittarius (3), NGC 147 (2), NGC 185 (5), NGC 205 (9), NGC 6822 (5), Leo A (1), and Sextans A (1). The data were acquired at the Observatorio Astronómico Nacional in the Sierra de San Pedro Mártir using the 2.1m telescope
Adam Moss, Douglas Scott, Kris Sigurdson
Recent claims in the literature have suggested that the {\it WMAP} quadrupole is not primordial in origin, and arises from an aliasing of the much larger dipole field because of incorrect satellite pointing. We attempt to reproduce this result and delineate the key physics leading to the effect. We find that, even if real, the induced quadrupole would be sma
An Oracle Strongly Separating Deterministic Time from Nondeterministic Time, via Kolmogorov Complexity
cs.CCDavid Doty
Hartmanis used Kolmogorov complexity to provide an alternate proof of the classical result of Baker, Gill, and Solovay that there is an oracle relative to which P is not NP. We refine the technique to strengthen the result, constructing an oracle relative to which a conjecture of Lipton is false.
R. A. Treumann, R. Nakamura, W. Baumjohann
The spontaneous onset of magnetic reconnection in thin collisionless current sheets is shown to result from a thermal-anisotropy driven magnetic Weibel-mode, generating seed-magnetic field {\sf X}-points in the centre of the current layer.
Interdependent networks: Reducing the coupling strength leads to a change from a first to second order percolation transition
physics.data-anRoni Parshani, Sergey V. Buldyrev, Shlomo Havlin
We study a system composed from two interdependent networks A and B, where a fraction of the nodes in network A depends on the nodes of network B and a fraction of the nodes in network B depends on the nodes of network A. Due to the coupling between the networks when nodes in one network fail they cause dependent nodes in the other network to also fail. This
Density of States Modulations from Oxygen Phonons in d-wave Superconductors: Reconciling Angle-Resolved Photoemission Spectroscopy and Scanning Tunneling Microscopy
cond-mat.supr-conS. Johnston, T. P. Devereaux
Scanning tunneling microscopy (STM) measurements have observed modulations in the density of states (DOS) of a number of high-T$_c$ cuprates. These modulations have been interpreted in terms of electron-boson coupling analogous to the dispersion "kinks" observed by angle-resolved photoemission spectroscopy (ARPES). However, a direct a reconciliation
Tibab McNeish, Godfrey Gumbs, Antonios Balassis
We calculate the plasma excitations in a bundle as well as a two-dimensional (2D) periodic array of aligned parallel multishell nanotubes on a substrate. The carbon nanotubes are oriented perpendicular to the substrate. The model we use for the system is an electron gas confined to the surface of an infinitely long cylinder embedded in a background dielectri
Mithun Das Gupta
In this paper we present a Bayesian image zooming/super-resolution algorithm based on a patch based representation. We work on a patch based model with overlap and employ a Locally Linear Embedding (LLE) based approach as our data fidelity term in the Bayesian inference. The image prior imposes continuity constraints across the overlapping patches. We apply
N. A. Poklonski, E. F. Kislyakov, Nguyen Ngoc Hieu, O. N. Bubel'
The Kekule structure of the ground state of (5,5) armchair carbon nanotube is revealed by semiempirical molecular orbital calculations. This structure has bonds with two different bond lengths, differing by 0.003 nm. The ground state has tripled (compared to undistorted case) translational period due to Peierls distortions. Two first order structural phase t
Angel Castro, Diego Cordoba, Francisco Gancedo
In this paper we study the Burgers equation with a nonlocal term of the form $Hu$ where $H$ is the Hilbert transform. This system has been considered as a quadratic approximation for the dynamics of a free boundary of a vortex patch. We prove blow up in finite time for a large class of initial data with finite energy. Considering a more general nonlocal term
Ivan Yudin
We show that the rank of the endomorphism monoid of a unifromly nested partition of depth k is 2k.
Dongfeng Gao, Kentaro Hori
We determine the structure of the Chan-Paton factors of the open strings ending on space filling D-branes in Type II orientifolds. Through the analysis, we obtain a rule concerning possible distribution of O-plane types. The result is applied to classify the topology of D-branes in terms of Fredholm operators and K-theory, deriving a proposal made earlier an
Milan Janjic
We first give a combinatorial interpretation of coefficients of Chebyshev polynomials, which allows us to connect them with compositions of natural numbers. Then we describe a relationship between the number of compositions of a natural number in which a certain number of parts are p-1, and other parts are not less than p with compositions in which all parts
Mehdi Karimi, Amir H. Banihashemi
A message-passing algorithm for counting short cycles in a graph is presented. For bipartite graphs, which are of particular interest in coding, the algorithm is capable of counting cycles of length g, g +2,..., 2g - 2, where g is the girth of the graph. For a general (non-bipartite) graph, cycles of length g; g + 1, ..., 2g - 1 can be counted. The algorithm
M. R. Zapatero Osorio, R. Rebolo, G. Bihain, V. J. S. Béjar
We report unusual near- and mid-infrared photometric properties of G 196-3 B, the young substellar companion at 16 arcsec from the active M2.5-type star G 196-3 A, using data taken with the IRAC and MIPS instruments onboard Spitzer. G 196-3 B shows markedly redder colors at all wavelengths from 1.6 up to 24 micron than expected for its spectral type, which i
Wan-Chen Chuang, Sen-Peng Eu, Tung-Shan Fu, Yeh-Jong Pan
A permutation $σ\in\mathfrak{S}_n$ is simsun if for all $k$, the subword of $σ$ restricted to $\{1,...,k\}$ does not have three consecutive decreasing elements. The permutation $σ$ is double simsun if both $σ$ and $σ^{-1}$ are simsun. In this paper we present a new bijection between simsun permutations and increasing 1-2 trees, and show a number of interesti
Chiang-Mei Chen, Jia-Rui Sun
Motivated by recent progresses in the holographic descriptions of the Kerr and Reissner-Nordstrøm (RN) black holes, we explore the hidden conformal symmetry of nonextremal uplifted 5D RN black hole by studying the near horizon wave equation of a massless scalar field propagating in this background. Similar to the Kerr black hole case, this hidden symmetry is
Thermodynamical description of stationary, asymptotically flat solutions with conical singularities
gr-qcCarlos Herdeiro, Eugen Radu, Carmen Rebelo
We examine the thermodynamical properties of a number of asymptotically flat, stationary (but not static) solutions having conical singularities, with both connected and non-connected event horizons, using the thermodynamical description recently proposed in arXiv:0912.3386 [gr-qc]. The examples considered are the double-Kerr solution, the black ring rotatin
Isaac Vidana, Domenico Logoteta, Constanza Providencia, Artur Polls
An analytic parametrization of the hyperonic matter equation of state based on microscopic Brueckner-Hartree-Fock calculations has been constructed using the realistic Argonne V18 nucleon-nucleon potential plus a three-body force of Urbana type, and three models of the hyperon-nucleon interaction: the Nijmegen soft-core models NSC89 and NSC97e, and the most
Magnetic excitations in the metallic single-layer Ruthenates Ca(2-x)Sr(x)RuO(4) studied by inelastic neutron scattering
cond-mat.str-elP. Steffens, O. Friedt, Y. Sidis, P. Link
By inelastic neutron scattering, we have analyzed the magnetic correlations in the paramagnetic metallic region of the series Ca(2-x)Sr(x)RuO(4), 0.2<=x<=0.62. We find different contributions that correspond to 2D ferromagnetic fluctuations and to fluctuations at incommensurate wave vectors (0.11,0,0), (0.26,0,0) and (0.3,0.3,0). These components constitute
Anatol Odzijewicz, Alina Dobrogowska
By application of the coinduction method as well as Magri method to the ideal of real Hilbert-Schmidt operators we construct the hierarchies of integrable Hamiltonian systems on the Banach Lie-Poisson spaces which consist of these type of operators. We also discuss their algebraic and analytic properties as well as solve them in dimensions N=2,3,4.
Christian Mulder, A. Jan Hendriks
Periodicity in population dynamics is a fundamental issue. In addition to current species-specific analyses, allometry facilitates understanding of limit cycles amongst different species. So far, body-size regressions have been derived for the oscillation period of the population densities of warm-blooded species, in particular herbivores. Here, we extend th
Eugene Livshitz
We show that if a matrix $Φ$ satisfies the RIP of order $[CK^{1.2}]$ with isometry constant $\dt = c K^{-0.2}$ and has coherence less than $1/(20 K^{0.8})$, then Orthogonal Matching Pursuit (OMP) will recover $K$-sparse signal $x$ from $y=Φx$ in at most $[CK^{1.2}]$ iterations. This result implies that $K$-sparse signal can be recovered via OMP by $M=O(K^{1.
Julian Külshammer
We give two new criteria for a basic algebra to be biserial. The first one states that an algebra is biserial iff all subalgebras of the form eAe where e is supported by at most 4 vertices are biserial. The second one gives some condition on modules that must not exist for a biserial algebra. These modules have properties similar to the module with dimension
Christian Krattenthaler
We show how to determine the asymptotics of a certain Selberg-type integral by means of tools available in the theory of (generalised) hypergeometric series. This provides an alternative derivation of a result of Carré, Deneufchâtel, Luque and Vivo [arXiv:1003.5996].
William Wilson, Phil Birkin, Uwe Aickelin
In this paper we outline initial concepts for an immune inspired algorithm to evaluate price time series data. The proposed solution evolves a short term pool of trackers dynamically through a process of proliferation and mutation, with each member attempting to map to trends in price movements. Successful trackers feed into a long term memory pool that can
F. Dahia, P. J. Felix da Silva
Static observers in curved spacetimes may interpret their proper acceleration as the opposite of a local gravitational field (in the Newtonian sense). Based on this interpretation and motivated by the equivalence principle, we are led to investigate congruences of timelike curves in Minkowski spacetime whose acceleration field coincides with the acceleration
Indecomposable and Noncrossed Product Division Algebras over Curves over Complete Discrete Valuation Rings
math.RAFeng Chen
Let T be a complete discrete valuation ring and $\hat{X}$ a smooth projective curve over $S=\spec(T)$ with closed fibre $X$. Denote by $F$ the function field of $\hat{X}$ and by $\hat{F}$ the completion of $F$ with respect to the discrete valuation defined by $X$, the closed fibre. In this paper, we construct indecomposable and noncrossed product division al
Wien2wannier: From linearized augmented plane waves to maximally localized Wannier functions
cond-mat.mtrl-sciJan Kunes, Ryotaro Arita, Philipp Wissgott, Alessandro Toschi
We present an implementaion of interface between the full-potential linearized augmented plane wave package Wien2k and the wannier90 code for the construction of maximally localized Wannier functions. The FORTRAN code and a documentation is made available and results are discussed for SrVO$_3$, Sr$_2$IrO$_4$ (including spin-orbit coupling), LaFeAsO, and FeSb
VLT-VIMOS integral field spectroscopy of luminous and ultraluminous infrared galaxies II. Evidence for shock ionization caused by tidal forces in the extra-nuclear regions of interacting and merging LIRGs
astro-ph.COAna Monreal-Ibero, Santiago Arribas, Luis Colina, Javier Rodriguez-Zaurin
LIRGs are an important class of objects in the low-z universe bridging the gap between normal spirals and the strongly interacting and starbursting ULIRGs. Studies of their 2D physical properties are still lacking. We aim to understand the nature and origin of the ionization mechanisms operating in the extranuclear regions of LIRGs as a function of the inter
Tien-Cuong Dinh, Viet-Anh Nguyen, Nessim Sibony
We introduce the heat equation relative to a positive dd-bar-closed current and apply it to the invariant currents associated with Riemann surface laminations possibly with singularities. The main examples are holomorphic foliations by Riemann surfaces in projective spaces. We prove two kinds of ergodic theorems for such currents: one associated to the heat
M. Nakano, H. Alves, A. S. Molinari, S. Ono
We investigated transport properties of organic heterointerfaces formed by single-crystals of two organic donor-acceptor molecules, tetramethyltetraselenafulvalene (TMTSF) and 7,7,8,8-tetracyanoquinodimethane (TCNQ). Whereas the individual crystals have un-measurably high resistance, the interface exhibits a resistivity of few tens of MegaOhm with a temperat
Gregory C. Dente
In order to obtain a reasonably accurate and easily implemented approach to many-electron calculations, we will develop a new Density Functional Theory (DFT). Specifically, we derive an approximation to electron density, the first term of which is the Thomas-Fermi density, while the remaining terms substantially correct the density near the nucleus. As a fir
Mark W. Johnson
Variations on the notions of Reedy model structures and projective model structures on categories of diagrams in a model category are introduced. These allow one to choose only a subset of the entries when defining weak equivalences, or to use different model categories at different entries of the diagrams. As a result, a bisimplicial model category that can
B. Z. Kopeliovich, I. K. Potashnikova, Ivan Schmidt
The dead cone effect has been expected to reduce the magnitude of energy loss and jet quenching for heavy flavors produced with large pT in heavy ion collisions. On the contrary, data from RHIC for open charm production demonstrate a flavor independent nuclear suppression. We show that vacuum radiation of a highly virtual quark produced at high pT with its c
Yousof Al-Hammadi, Uwe Aickelin, Julie Greensmith
Malicious users try to compromise systems using new techniques. One of the recent techniques used by the attacker is to perform complex distributed attacks such as denial of service and to obtain sensitive data such as password information. These compromised machines are said to be infected with malicious software termed a "bot". In this paper, we in
Tibor Toeroek, Mitchell A. Berger, Bernhard Kliem
Helicity is a fundamental property of magnetic fields, conserved in ideal MHD. In flux rope topology, it consists of twist and writhe helicity. Despite the common occurrence of helical structures in the solar atmosphere, little is known about how their shape relates to the writhe, which fraction of helicity is contained in writhe, and how much helicity is ex
S. Grzedzielski, M. Bzowski, A. Czechowski, H. O. Funsten
The brightest and most surprising feature in the first all-sky maps of Energetic Neutral Atoms (ENA) emissions (0.2-6 keV) produced by the Interstellar Boundary Explorer (IBEX) is an almost circular ribbon of a ~140° opening angle, centered at (l,b) = (33°, 55°), covering the part of the celestial sphere with the lowest column densities of the Local Interste
Elizabeth Gasparim, Thomas Köppe
We prove existence of reflexive sheaves on singular surfaces and threefolds with prescribed numerical invariants and study their moduli.
V. L. Gurtovoi, A. I. Ilin, A. V. Nikulov, V. A. Tulin
Experimental results obtained last years corroborate a prediction made by I.O. Kulik forty years ago that the energy dissipation does not result in disappearance of equilibrium circular current observable in the normal state of superconductor rings and normal metal rings. Contrary interpretations of the persistent current as a Brownian motion or a dissipatio
M. Novello, E. Bittencourt
We present the whole class of Gaussian coordinate systems for the Kerr metric. This is achieved through the uses of the relationship between Gaussian observers and the relativistic Hamilton-Jacobi equation. We analyze the completeness of this coordinate system. In the appendix we present the equivalent JEK formulation of General Relativity -- the so-called q
Vincent L. Fish, Loránt O. Sjouwerman
We present global VLBI observations of the first-excited state OH masers in the massive star-forming region Onsala 1 (ON 1). The 29 masers detected are nearly all from the 6035 MHz transition, and nearly all are identifiable as Zeeman pair components. The 6030 and 6035 MHz masers are coincident with previously published positions of ground-state masers to wi
Critical current and vortex dynamics in single crystals of Ca(Fe$_{1-x}$Co$_{x}$)$_2$As$_2$
cond-mat.supr-conA. K. Pramanik, L. Harnagea, S. Singh, S. Aswartham
We investigate the critical current density and vortex dynamics in single crystals of Ca(Fe$_{1-x}$Co$_{x}$)$_2$As$_2$ ($x$ = 0.051, 0.056, 0.065, and 0.073). The samples exhibit different critical temperatures and superconducting phase fractions. We show that in contrast to their Ba-based counterpart, the crystals do not exhibit a second peak in the field d
A. Plecenik, M. Tomasek, T. Plecenik, M. Truchly
Current-voltage characteristics of planar junctions formed by an epitaxial c-axis oriented YBa2Cu3O7-x thin film micro-bridge and Ag counter-electrode were measured in the temperature range from 4.2 K to 300 K. A hysteretic behavior related to switching of the junction resistance from a high-resistive to a low-resistive state and vice-versa was observed and
Sedighe Sajadian, Sohrab Rahvar
In recent years a large number of Hot Jupiters orbiting in a very close orbit around the parent stars have been explored with the transit and doppler effect methods. Here in this work we study the gravitational microlensing effect of a binary lens on a parent star with a Hot Jupiter revolving around it. Caustic crossing of the planet makes enhancements on th
H. Bahlouli, A. D. Alhaidari
A new solvable hyperbolic single wave potential is found by expanding the regular solution of the 1D Schrödinger equation in terms of square integrable basis. The main characteristic of the basis is in supporting an infinite tridiagonal matrix representation of the wave operator. However, the eigen-energies associated with this potential cannot be obtained u
A. D. Alhaidari
This is the second article in a series where we succeed in enlarging the class of solvable problems in one and three dimensions. We do that by working in a complete square integrable basis that carries a tridiagonal matrix representation of the wave operator. Consequently, the wave equation becomes equivalent to a three-term recursion relation for the expans
Arkadiusz Pĺoski
Let $F(X,Y)=Y^d+a_1(X)Y^{d-1}+...+a_d(X)$ be a polynomial in $n+1$ variables $(X,Y)=(X_1,...,X_n,Y)$ with coefficients in an algebraically closed field K. Assuming that the discriminant $D(X)=\disc_Y F(X,Y)$ is nonzero we investigate the order $\ord_P D$ for $P\in K^n$. As application we get a discriminant criterion for the hypersurface F=0 to be nonsingular
Anti-Coarsening and Complex Dynamics of Step Bunches on Vicinal Surfaces during Sublimation
cond-mat.stat-mechMarian Ivanov, Vladislav Popkov, Joachim Krug
A sublimating vicinal crystal surface can undergo a step bunching instability when the attachment-detachment kinetics is asymmetric, in the sense of a normal Ehrlich-Schwoebel effect. Here we investigate this instability in a model that takes into account the subtle interplay between sublimation and step-step interactions, which breaks the volume-conserving
A. D. Alhaidari
We consider the Dirac equation in 3+1 dimensions with spherical symmetry and coupling to 1/r singular vector potential. An approximate analytic solution for all angular momenta is obtained. The approximation is made for the 1/r orbital term in the Dirac equation itself not for the traditional and more singular 1/r^2 term in the resulting second order differe
Photoconductance of a submicron oxidized line in surface conductive single crystalline diamond
cond-mat.mes-hallM. Stallhofer, M. Seifert, M. Hauf, G. Abstreiter
We report on sub-bandgap optoelectronic phenomena of hydrogen-terminated diamond patterned with a submicron oxidized line. The line acts as an energy barrier for the two-dimensional hole gas located below the hydrogenated diamond surface. A photoconductive gain of the hole conductivity across the barrier is measured for sub-bandgap illumination. The findings
Tatsuo Azeyanagi, Masafumi Fukuma, Hikaru Kawai, Kentaroh Yoshida
We review our recent proposal for a universal description of generic single-component viscoelastic systems with a single relaxation time. Foliation preserving diffeomorphisms are introduced as an underlying symmetry which naturally interpolates between the two extreme characters of elasticity and fluidity. The symmetry is found to be powerful enough to deter
A. D. Alhaidari, H. Bahlouli, M. S. Abdelmonem
We formulate a theory of nonrelativistic scattering in one dimension based on the J-matrix method. The scattering potential is assumed to have a finite range such that it is well represented by its matrix elements in a finite subset of a basis that supports a tridiagonal matrix representation for the reference wave operator. Contrary to our expectation, the
Vortex structures of rotating Bose-Einstein condensates in anisotropic harmonic potential
cond-mat.quant-gasS. I. Matveenko
We found an analytical solution for the vortex structure in a rapidly rotating trapped Bose-Einstein condensate in the lowest Landau level approximation. This solution is exact in the limit of a large number of vortices and is obtained for the case of anisotropic harmonic potential. For the case of symmetric harmonic trap when the rotation frequency is equal
Optimally Robust Kalman Filtering at Work: AO-, IO-, and Simultaneously IO- and AO- Robust Filters
stat.COPeter Ruckdeschel
We take up optimality results for robust Kalman filtering from Ruckdeschel[2001,2010] where robustness is understood in a distributional sense, i.e.; we enlarge the distribution assumptions made in the ideal model by suitable neighborhoods, allowing for outliers which in our context may be system-endogenous/propagating or -exogenous/non-propagating, inducing
Christoph Petri, Florian Lenz, Fotis K. Diakonos, Peter Schmelcher
We explore the dynamics of non-interacting particles loaded into a phase-modulated one-dimensional lattice formed by laterally oscillating square barriers. Tuning the parameters of the driven unit cell of the lattice selected parts of the classical phase space can be manipulated in a controllable manner. We find superdiffusion in position space for all param
A. D. Alhaidari, H. Bahlouli, A. Jellal
We obtain exact scattering solutions of the Dirac equation in 1+1 dimensions for a double square barrier vector potential. The potential floor between the two barriers is higher than 2mc^2 whereas the top of the barriers is at least 2mc^2 above the floor. The relativistic version of the conventional double barrier transmission resonance is obtained for energ
Masayoshi Nobukawa, Katsuji Koyama, Takeshi Go Tsuru, Syukyo G Ryu
The K-shell emission line of neutral irons from the Galactic center (GC) region is one of the key for the structure and activity of the GC. The origin is still open question, but possibly due either to X-ray radiation or to electron bombarding to neutral atoms. To address this issue, we analyzed the Suzaku X-ray spectrum from the GC region of intense neutral
Rafael Lopez, Marian Ioan Munteanu
In this paper we classify all surfaces in the 3-dimensional Lie group $Sol_3$ whose normals make constant angle with a left invariant vector field.
William Wilson, Phil Birkin, Uwe Aickelin
The search for patterns or motifs in data represents an area of key interest to many researchers. In this paper we present the Motif Tracking Algorithm, a novel immune inspired pattern identification tool that is able to identify variable length unknown motifs which repeat within time series data. The algorithm searches from a completely neutral perspective
A. I. Rykov
A new method for investigating the particle size distribution (PSD) is suggested using the nuclear forward scattering (NFS) of synchrotron radiation. The distribution of Weibull-Gnedenko is used to illustrate the relationship between the NFS lineshape and PSD.
Marco Cappiello, Fabio Nicola
We prove, for a wide class of semilinear elliptic differential and pseudodifferential equations in $\R^d$, that the solutions which are sufficiently regular and have a certain decay at infinity extend to holomorphic functions in sectors of $\mathbb{C}^d$, improving earlier results where the extension was shown for a strip. Moreover, exponential decay for suc
WIlliam Wilson, Phil Birkin, Uwe Aickelin
We outline initial concepts for an immune inspired algorithm to evaluate and predict oil price time series data. The proposed solution evolves a short term pool of trackers dynamically, with each member attempting to map trends and anticipate future price movements. Successful trackers feed into a long term memory pool that can generalise across repeating tr
Constraints on the inner edge of neutron star crusts from relativistic nuclear energy density functionals
nucl-thCh. C. Moustakidis, T. Niksic, G. A. Lalazissis, D. Vretenar
The transition density $n_t$ and pressure $P_t$ at the inner edge between the liquid core and the solid crust of a neutron star are analyzed using the thermodynamical method and the framework of relativistic nuclear energy density functionals. Starting from a functional that has been carefully adjusted to experimental binding energies of finite nuclei, and v
S. Matthews, D. Baker, S. Vargas Domínguez
Recent observations of sunspot light-bridges have shed new light on the fact that they are often associated with significant chromospheric activity. In particular chromospheric jets (Shimizu et al. 2009) persisting over a period of days have been identifies, sometimes associated with large downflows at the photospheric level (Louis et al. 2009). One possible
Patrick Kuppinger, Giuseppe Durisi, Helmut Bölcskei
As shown by Tropp, 2008, for the concatenation of two orthonormal bases (ONBs), breaking the square-root bottleneck in compressed sensing does not require randomization over all the positions of the nonzero entries of the sparse coefficient vector. Rather the positions corresponding to one of the two ONBs can be chosen arbitrarily. The two-ONB structure is,
Rubens E. G. Machado, E. Athanassoula
Cosmological N-body simulations indicate that the dark matter haloes of galaxies should be generally triaxial. Yet, the presence of a baryonic disc is believed to alter the shape of the haloes. Here we aim to study how bar formation is affected by halo triaxiality and how, in turn, the presence of the bar influences the shape of the halo. We perform a set of
Koichi Hirano, Zen Komiya
We propose a phantom crossing Dvali--Gabadadze--Porrati (DGP) model. In our model, the effective equation of state of the DGP gravity crosses the phantom divide line. We demonstrate crossing of the phantom divide does not occur within the framework of the original DGP model or the DGP model developed by Dvali and Turner. By extending their model, we construc
More on Dimension-4 Proton Decay Problem in F-theory -- Spectral Surface, Discriminant Locus and Monodromy
hep-thHirotaka Hayashi, Teruhiko Kawano, Yoichi Tsuchiya, Taizan Watari
Factorized spectral surface scenario has been considered as one of solutions to the dimension-4 proton decay problem in supersymmetric compactifications of F-theory. It has been formulated in language of gauge theory on 7+1 dimensions, but the gauge theories descriptions can capture physics of geometry of F-theory compactification only approximately at best.
S. Colafrancesco
The presence of Dark Matter (DM) is required in the universe regulated by the standard general relativistic theory of gravitation. The nature of DM is however still elusive to any experimental search. We discuss here the process of accumulation of evidence for the presence of DM in the universe, the astrophysical probes for the leading DM scenarios that can
The role of light ellipticity in ionization of atoms by intense few-cycles laser pulses
physics.atom-phM. Abu-samha, L. B. Madsen
We provide theoretical investigations of the response of the Ar and H atoms to an intense elliptically polarized few-cycle laser pulse, as a function of light ellipticity. The time-dependent Schr{ö}dinger equation describing the least-bound electron is solved numerically, and differential quantities such as the momentum distribution, the electron density in
Alexei Pokrovskii, Dmitrii Rachinskii, Vladimir Sobolev, Andrew Zhezherun
We propose sufficient conditions for existence of topologically stable periodic canard solutions in non-smooth slow-fast systems.
O. Astafiev, A. A. Abdumalikov, A. M. Zagoskin, Yu. A. Pashkin
We report amplification of electromagnetic waves by a single artificial atom in open 1D space. Our three-level artificial atom -- a superconducting quantum circuit -- coupled to a transmission line presents an analog of a natural atom in open space. The system is the most fundamental quantum amplifier whose gain is limited by a spontaneous emission mechanism
Electrically assisted light-induced azimuthal gliding of the nematic liquid crystal easy axis on photoaligned substrates
cond-mat.softA. V. Dubtsov, S. V. Pasechnik, Alexei D. Kiselev, D. V. Shmeliova
We study azimuthal gliding of the easy axis that occurs in nematic liquid crystals brought in contact with the photoaligned azo-dye film under the action of reorienting UV light combined with an in-plane electric field. For irradiation with the linearly polarized light, dynamics of easy axis reorientation is found to be faster as compared to the case of non-
Giant crystal-electric-field effect and complex magnetic behavior in single-crystalline CeRh3Si2
cond-mat.str-elA. P. Pikul, D. Kaczorowski, Z. Gajek, J. Stepien--Damm
Single-crystalline CeRh3Si2 was investigated by means of x-ray diffraction, magnetic susceptibility, magnetization, electrical resistivity, and specific heat measurements carried out in wide temperature and magnetic field ranges. Moreover, the electronic structure of the compound was studied at room temperature by cerium core-level x-ray photoemission spectr
Jevgenijs Ivanovs
We present a new approach to fluctuation identities for reflected Lévy processes with one-sided jumps. This approach is based on a number of easy to understand observations and does not involve excursion theory or Itô calculus. It also leads to more general results.
Motion of Space Curves in Three-dimensional Minkowski Space $R_1^{3}$, SO(2,1) Spin Equation and Defocusing Nonlinear Schrödinger Equation
nlin.SIGopal Muniraja, M. Lakshmanan
We consider the dynamics of moving curves in three-dimensional Minkowski space $R_1^{3}$ and deduce the evolution equations for the curvature and torsion of the curve. Next by mapping a continuous SO(2,1) Heisenberg spin chain on the space curve in $R_1^{3}$, we show that the defocusing nonlinear Schrödinger equation(NLSE) can be identified with the spin cha
Ognian Kassabov
It is proved, that if an almost Hermitian manifold satisfies the axiom of coholomorphic spheres, it is conformal flat.
Jiri Krticka, Viktor Votruba, Jiri Kubat
During the evolution of rotating first stars, which initially consisted of only hydrogen and helium, CNO elements may emerge to their surface. These stars may therefore have winds that are driven only by CNO elements. We study weak wind effects (Gayley-Owocki heating and multicomponent effects) in stellar winds of first generation stars driven purely by CNO
Christophe Coste, Jean-Baptiste Delfau, Catherine Even, Michel Saint Jean
In this paper, we study a macroscopic system of electrically interacting metallic beads organized as a sequence along an annulus. A random mechanical shaking mimics the thermal excitation. We exhibit non Fickian diffusion (Single File Diffusion) at large time. We measure the mobility of the particles, and compare it to theoretical expectations. We show that
Luca Baiotti, Ian Hawke, Pedro J. Montero, Luciano Rezzolla
We present a new three-dimensional general relativistic hydrodynamics code, the Whisky code. This code incorporates the expertise developed over the past years in the numerical solution of Einstein equations and of the hydrodynamics equations in a curved spacetime, and is the result of a collaboration of several European Institutes. We here discuss the abili
Superconducting order parameter in nonmagnetic borocarbides RNi$_{2}$B$_{2}$C (R=Y, Lu) probed by point-contact Andreev reflection spectroscopy
cond-mat.supr-conX. Lu, W. K. Park, S. Yeo, K. -H. Oh
We report on the measurements of the superconducting order parameter in the nonmagnetic borocarbides LuNi$_2$B$_2$C and YNi$_2$B$_2$C. Andreev conductance spectra are obtained from nanoscale metallic junctions on single crystal surfaces prepared along three major crystallographic orientations: [001], [110], and [100]. The gap values extracted by the single-g