July 2011 arXiv papers — page 2

Yohan Dubois, Julien Devriendt, Adrianne Slyz, Romain Teyssier

We develop a new sub-grid model for the growth of supermassive Black Holes (BHs) and their associated Active Galactic Nuclei (AGN) feedback in hydrodynamical cosmological simulations. Assuming that BHs are created in the early stages of galaxy formation, they grow by mergers and accretion of gas at a Eddington-limited Bondi accretion rate. However this growt

E. D. Koultoukis, S. S. Makridis, L. Röntzsch, E. Pavlidou

In this work, TiFe-based alloys have been developed according to the stoichiometry Ti1-xAxFe1-yBy (A \equiv Zr; B \equiv Mn, V). The hydrogen solubility properties have been investigated to develop dynamic hydrides of Ti-based alloys for hydrogen storage applications. The hydrogenation behavior of these alloys has been studied, and their hydrogen storage cap

Hélène Esnault, Adrian Langer

Our aim is to formulate and prove a weak form in equal characteristic $p>0$ of the $p$-curvature conjecture. We also show the existence of a counterexample to a strong form of it.

Vladimir Filimonov, Didier Sornette

We present a simple transformation of the formulation of the log-periodic power law formula of the Johansen-Ledoit-Sornette model of financial bubbles that reduces it to a function of only three nonlinear parameters. The transformation significantly decreases the complexity of the fitting procedure and improves its stability tremendously because the modified

Jing-Jing Huang

In this paper, we prove an asymptotic formula for the average number of solutions to the Diophantine equation $axy-x-y=n$ in which $a$ is fixed and and $n$ varies.

Shannon X. Wang, Guang Hao Low, Nathan S. Lachenmyer, Yufei Ge

Electrical charging of metal surfaces due to photoelectric generation of carriers is of concern in trapped ion quantum computation systems, due to the high sensitivity of the ions' motional quantum states to deformation of the trapping potential. The charging induced by typical laser frequencies involved in doppler cooling and quantum control is studied

G. Y. Liang, N. R. Badnell, G. Zhao, J. Y. Zhong

We present results for the electron-impact excitation of highly-charged sulphur ions (S8+ - S11+) obtained using the intermediate-coupling frame transformation R-matrix approach. A detailed comparison of the target structure has been made for the four ions to assess the uncertainty on collision strengths from the target structure. Effective collision strengt

Hao Wang, V. W. Scarola

Graphene based nanostructures exhibit flat electronic energy bands in their single-particle spectrum. We consider interacting electrons in flat bands of zig-zag nanoribbons. We present a protocol for flat-band projection that yields interaction-only tight-binding models. We argue that, at low densities, flat bands can delocalize single-particle basis states

Tomasz Komorowski, Łukasz Stȩpień

We consider the long time, large scale behavior of the Wigner transform $W_\eps(t,x,k)$ of the wave function corresponding to a discrete wave equation on a 1-d integer lattice, with a weak multiplicative noise. This model has been introduced in Basile, Bernardin, and Olla to describe a system of interacting linear oscillators with a weak noise that conserves

Henni Ouerdane

The main objective of the present work is the development of an analytically tractable model of screened electron-electron and electron-exciton interactions in layered systems composed of two parallel semiconductor quantum wells separated by a dielectric layer. These systems are promising for superconductivity with excitons-polaritons, and spin manipulation.

Luca Salasnich

We analyze the BCS-BEC crossover for a Fermi gas made of neutral atoms in three hyperfine states with a SU(3) invariant attractive interaction. By solving the extended BCS equations for the total number of particles and the pairing gap, we calculate at zero temperature the pairing gap, the population imbalance, the condensate fraction and the first sound vel

Gautam Iyer, Tomasz Komorowski, Alexei Novikov, Lenya Ryzhik

We consider an elliptic eigenvalue problem with a fast cellular flow of amplitude $A$, in a two-dimensional domain with $L^2$ cells. For fixed $A$, and $L \to \infty$, the problem homogenizes, and has been well studied. Also well studied is the limit when $L$ is fixed, and $A \to \infty$. In this case the solution equilibrates along stream lines. In this pap

Kazunori Nakayama, Fuminobu Takahashi

We investigate an inflation model with the inflaton being identified with a Higgs boson responsible for the breaking of U(1)B-L symmetry. We show that supersymmetry must remain a good symmetry at scales one order of magnitude below the inflation scale, in order for the inflation model to solve the horizon and flatness problems, as well as to account for the

Paul H. Frampton, Kevin J. Ludwick, Shin'ichi Nojiri, Sergei D. Odintsov

We examine in more detail specific models which yield a little rip cosmology, i.e., a universe in which the dark energy density increases without bound but the universe never reaches a finite-time singularity. We derive the conditions for the little rip in terms of the inertial force in the expanding universe and present two representative models to illustra

M. Chertkov, A. B. Yedidia

We discuss schemes for exact and approximate computations of permanents, and compare them with each other. Specifically, we analyze the Belief Propagation (BP) approach and its Fractional Belief Propagation (FBP) generalization for computing the permanent of a non-negative matrix. Known bounds and conjectures are verified in experiments, and some new theoret

Vaughn Climenhaga

Multifractal analysis studies level sets of asymptotically defined quantities in a topological dynamical system. We consider the topological pressure function on such level sets, relating it both to the pressure on the entire phase space and to a conditional variational principle. We use this to recover information on the topological entropy and Hausdorff di

José Luis Jaramillo, Rodrigo P. Macedo, Philipp Moesta, Luciano Rezzolla

In a companion paper [1], we have presented a cross-correlation approach to near-horizon physics in which bulk dynamics is probed through the correlation of quantities defined at inner and outer spacetime hypersurfaces acting as test screens. More specifically, dynamical horizons provide appropriate inner screens in a 3+1 setting and, in this context, we hav

José Luis Jaramillo, Rodrigo P. Macedo, Philipp Moesta, Luciano Rezzolla

The understanding of strong-field dynamics near black-hole horizons is a long-standing and challenging prob- lem in general relativity. Recent advances in numerical relativity and in the geometric characterization of black- hole horizons open new avenues into the problem. In this first paper in a series of two, we focus on the analysis of the recoil occurrin

Peter Orland

Correlation functions of matrix-valued fields are not generally known for massive renormalized field theories. We find the large-N limit of form factors of the (1+1)-dimensional sigma model with SU(N) X SU(N) symmetry. These form factors give a correction to the free-field approximation for the N=infinity Wightman function. The method is a combination of the

Petr Hajicek

In our previous work, a new approach to the notorious problem of quantum measurement was proposed. Existing treatments of the problem were incorrect because they ignored the disturbance of measurement by identical particles and standard quantum mechanics had to be modified to obey the cluster separability principle. The key tool was the notion of separation

Elena Beretta, Elisa Francini, Sergio Vessella

In this paper we estimate the size of a measurable inclusion in terms of power measurements for a single applied boundary current. This problem arises in medical imaging for the screening of organs. For this kind of problem one has to deal mathematically with the complex conductivity (admittivity) equation. In this case we are able to establish, for certain

Avik Dutt, Trisha Nath, Sayan Kar, Rajesh Parwani

A classic no-go theorem in one-dimensional quantum mechanics can be evaded when the potentials are unbounded below, thus allowing for novel parity-paired degenerate energy bound states. We numerically determine the spectrum of one such potential and study the parametric variation of the transition wavelength between a bound state lying inside the valley of t

A. B. Arbuzov, M. K. Volkov

Electromagnetic interactions of the ground and first radial excited states of $η$ and $η'$ mesons in the framework of the extended $U(3)\times U(3)$ NJL model are considered. The radial excitations are described with the help of polynomial form factor of the second order over the inner quark momentum. The solution of the $U_A(1)$ problem by means of &#39

O. O. Kit, T. Tallinen, L. Mahadevan, J. Timonen

Although carbon nanotubes consist of honeycomb carbon, they have never been fabricated from graphene directly. Here, it is shown by quantum molecular-dynamics simulations and classical continuum-elasticity modeling, that graphene nanoribbons can, indeed, be transformed into carbon nanotubes by means of twisting. The chiralities of the tubes thus fabricated c

Stefano Beretta, Paola Bonizzoni, Gianluca Della Vedova, Raffaella Rizzi

Next-generation sequencing (NGS) technologies allow new methodologies for alternative splicing (AS) analysis. Current computational methods for AS from NGS data are mainly focused on predicting splice site junctions or de novo assembly of full-length transcripts. These methods are computationally expensive and produce a huge number of full-length transcripts

Peter C. Gibson, Michael P. Lamoureux

We present constructive solutions to the following Pólya-Schur problems concerning linear operators on the space of univariate polynomials: Given subsets $Ω_1$ and $Ω_2$ of the complex plane, determine operators that map all polynomials having no zeros in $Ω_1$ to polynomials having no zeros in $Ω_2$, or to the zero polynomial. We describe an explicit class

Gentaro Watanabe, Sukjin Yoon, Franco Dalfovo

We investigate the energy band structure of the superfluid flow of ultracold dilute Fermi gases in a one-dimensional optical lattice along the BCS to BEC crossover within a mean-field approach. In each side of the crossover region, a loop structure (swallowtail) appears in the Bloch energy band of the superfluid above a critical value of the interaction stre

Nitin Chandra, Sandeep Chatterjee

We study thermodynamics of an ideal gas in Doubly Special Relativity. New type of special functions (which we call Incomplete Modified Bessel functions) emerge. We obtain a series solution for the partition function and derive thermodynamic quantities. We observe that DSR thermodynamics is non-perturbative in the SR and massless limits. A stiffer equation of

Michael P. Salem

To compute the spectrum of bubble collisions seen by an observer in an eternally-inflating multiverse, one must choose a measure over the diverging spacetime volume, including choosing an "initial" hypersurface below which there are no bubble nucleations. Previous calculations focused on the case where the initial hypersurface is pushed arbitrarily d

Atilim Gunes Baydin, Ramon Lopez de Mantaras, Simeon Simoff, Carles Sierra

Mediation is an important method in dispute resolution. We implement a case based reasoning approach to mediation integrating analogical and commonsense reasoning components that allow an artificial mediation agent to satisfy requirements expected from a human mediator, in particular: utilizing experience with cases in different domains; and structurally tra

Sébastien Comerón, Bruce G. Elmegreen, Johan H. Knapen, Heikki Salo

Most, if not all, disk galaxies have a thin (classical) disk and a thick disk. In most models thick disks are thought to be a necessary consequence of the disk formation and/or evolution of the galaxy. We present the results of a study of the thick disk properties in a sample of carefully selected edge-on galaxies with types ranging from T=3 to T=8. We fitte

Liat Kessler, Andreea C. Nicoara

It is shown that Denjoy-Carleman quasi analytic rings of germs of functions in two or more variables either complex or real valued that are stable under derivation and strictly larger than the ring of real-analytic germs are not Noetherian rings. The failure of Weierstrass division on these Denjoy-Carleman classes yields a contradiction to Noetherianity via

Hironori Kumura

This paper, focusing on the growth rate of the measure, gives pointwise bounds of solutions of eigenvalue equations of the Laplace-Beltrami operator on noncompact Riemannian manifolds.

Ciprian Manolescu

Ozsvath and Szabo gave a combinatorial description of knot Floer homology based on a cube of resolutions, which uses maps with twisted coefficients. We study the t=1 specialization of their construction. The associated spectral sequence converges to knot Floer homology, and we conjecture that its E_1 page is isomorphic to the HOMFLY-PT chain complex of Khova

M. Sharif, H. Rizwana Kausar

We consider the modified $f(R)$ theory of gravity whose higher order curvature terms are interpreted as a gravitational fluid or dark source. The gravitational collapse of a spherically symmetric star, made up of locally anisotropic viscous fluid, is studied under the general influence of the curvature fluid. Dynamical equations and junction conditions are m

M. Sharif, G. Abbas

This paper is devoted to study the dynamics of gravitational collapse in the Misner and Sharp formalism. We take non-viscous heat conducting charged anisotropic fluid as a collapsing matter with cylindrical symmetry. The dynamical equations are derived and coupled with the transport equation for heat flux obtained from the M$\ddot{u}$ller-Israel-Stewart caus

Salman Malik, Alonso Silva, Jean-Marc Kelif

In this paper, we study the optimal placement and optimal number of base stations added to an existing wireless data network through the interference gradient method. This proposed method considers a sub-region of the existing wireless data network, hereafter called region of interest. In this region, the provider wants to increase the network coverage and t

A. E. Cárcamo Hernández

In the context of a strongly coupled Electroweak Symmetry Breaking, composite triplet of heavy vectors belonging to the $SU(2)_{L+R}$ adjoint representation and a composite scalar singlet under $SU(2)_{L+R}$ may arise from a new strong interaction invariant under the global $SU(2)_L\times SU(2)_R$ symmetry, which is spontaneously broken down to $SU(2)_{L+R}$

Fernando Charro, Guido De Philippis, Agnese Di Castro, Davi Máximo

We prove $L^\infty$ bounds and estimates of the modulus of continuity of solutions to the Poisson problem for the normalized infinity and $p$-Laplacian, namely \[ -Δ_p^N u=f\qquad\text{for $n<p\leq\infty$.} \] We are able to provide a stable family of results depending continuously on the parameter $p$. We also prove the failure of the classical Alexandrov-B

Niranjan Shivaram, Henry Timmers, Xiao-Min Tong, Arvinder S. Sandhu

Using extreme-ultraviolet attosecond-pulse-trains, we investigate the photoionization dynamics of a Helium atom in the presence of moderately-strong (~10^12 W/cm^2) femtosecond laser pulses. The electronic structure of a laser-dressed atom is traced in real-time through precision measurements of ion-yields and photo-electron angular distributions. Quantum in

Don N. Page

When one combines multiverse predictions by Bousso, Hall, and Nomura for the observed age and size of the universe in terms of the proton and electron charge and masses with anthropic predictions of Carter, Carr, and Rees for these masses in terms of the charge, one gets that the age of the universe should be roughly the inverse 64th power, and the cosmologi

Dimitris Kontogiannis

In this paper we are interested in the application of ergodic theory in integral functionals defined in generalizes Sobolev-Orlicz spaces. We provide examples of inhomogeneous, random media based on continuum percolation models that have been introduced in a previous paper. Finally we apply the limit theorem to the homogenization method introduced by E. Khru

A. V. Poshakinskiy, S. A. Tarasenko

We develop a microscopic theory of spin relaxation of a two-dimensional electron gas in quantum wells with anisotropic electron scattering. Both precessional and collision-dominated regimes of spin dynamics are studied. It is shown that, in quantum wells with noncentrosymmetric scatterers, the in-plane and out-of-plane spin components are coupled: spin depha

Özlem Yeşiltaş

Within the ideas of pseudo-supersymmetry, we have studied a non-Hermitian Hamiltonian $H_{-}=ω(ξ^† ξ+\1/2)+αξ^{2}+βξ^{†2}$, where $α\neq β$ and $ξ$ is a first order differential operator, to obtain the partner potentials $V_{+}(x)$ and $V_{-}(x)$ which are new isotonic and isotonic nonlinear oscillators, respectively, as the Hermitian equivalents of the non-

Boris B. Benyaminov

A hypothesis is put forward regarding the function $π_2(x)$ which describes the distribution of twin primes in the set of natural numbers. The function $π_2(x)$ is tested by evaluation and an empirical $π_2^{\ast}(x)$ is arrived at, which is shown to be highly accurate. Several other questions are also addressed.

E. A. Tsiligkeridis, S. S. Makridis, E. Pavlidou, E. S. Kikkinides

Perovskites are mixed oxides with the general formula ABO3. Many different compositions have been found to be possible and their number is growing rapidly due to their characteristics that make them ideal for various applications, such as fabrication of cathodes for solid oxide fuel cells (SOFCs). Oxide powders of LaxSr1-xCo1-y-zFeyMnzO3-δ (x=0.4, 0.6, 0.8,

R. Žitko, H. J. P. Van Midden, E. Zupanič, A. Prodan

Titanium borates show promissing hydrogen storage characteristics. Structural relaxation around individual hydrogen atoms and the binding energies are studied by means of the density functional theory methods for a number of hydrogenated TiB2, TiB and Ti2B structures. Starting with the possible symmetric hydrogen sites a random structure searching has been p

CDF Collaboration

We present a search for new physics in events with two high $p_T$ leptons of the same electric charge, using data with an integrated luminosity of 6.1 fb$^{-1}$. The observed data are consistent with standard model predictions. We set 95% C.L. lower limits on the mass of doubly-charged scalars decaying to like-sign dileptons, $m_{H^{\pm\pm}}> 190-245$ GeV/$c

Jiangyuan Li, Athina P. Petropulu

A multiple-input single-output (MISO) wiretap channel model is considered, that includes a multi-antenna transmitter, a single-antenna legitimate receiver and a single-antenna eavesdropper. For the scenario in which spherical uncertainty for both the legitimate and the eavesdropper channels is included, the problem of finding the optimal input covariance tha

Tom LaGatta

We introduce Riemannian First-Passage Percolation (Riemannian FPP) as a new model of random differential geometry, by considering a random, smooth Riemannian metric on $\mathbb R^d$. We are motivated in our study by the random geometry of first-passage percolation (FPP), a lattice model which was developed to model fluid flow through porous media. By adaptin

David G. Tempel, Alan Aspuru-Guzik

We prove that the theorems of TDDFT can be applied to a class of qubit Hamiltonians that are universal for quantum computation. The theorems of TDDFT applied to universal Hamiltonians imply that single-qubit expectation values can be used as the basic variables in quantum computation and information theory, rather than wavefunctions. From a practical standpo

Jing-Jing Huang, Robert C. Vaughan

In this paper, we establish two mean value theorems for the number of solutions of the Diophantine equation $\frac{a}{n}=\frac{1}{x}+\frac{1}{y}$, in the case when $a$ is fixed and $n$ varies and in the case when both $a$ and $n$ vary.

Debashis Ghoshal

We consider the inhomogeneous decay of an unstable D-brane. The dynamical equation that describes this process (in light-cone time) is a variant of the non-linear reaction-diffusion equation that first made its appearance in the pioneering work of (Luther and) Fisher and appears in a variety of natural phenomena.

D. V. Chibisov, V. S. Mikhailenko, K. N. Stepanov

An extension of hydrodynamic D&#39;Angelo mode of inhomogeneous sheared plasma flow along the magnetic field into the short-wavelength limit, where the hydrodynamic treatment is not valid, has been considered. We find that D&#39;Angelo mode in this wavelength range is excited by inverse ion Landau damping and becomes the shear flow driven ion-kinetic mode.

V. A. Abramovsky, N. V. Radchenko

We show that analysis of nonrelativistic neutron-proton scattering in a framework of relativistic QCD based quark model can give important information about QCD vacuum structure. In this model we describe total cross section of neutron-proton scattering at kinetic energies of projectile neutron from 1 eV up to 1 MeV.

Nail H. Ibragimov

The Riccati equations reducible to first-order linear equations by an appropriate change the dependent variable are singled out. All these equations are integrable by quadrature. A wide class of linear ordinary differential equations reducible to algebraic equations is found. It depends on two arbitrary functions. The method for solving all these equations i

Mitja Lakner, Peter Petek, Marjeta Škapin Rugelj

Quadratic irrationals posses a periodic continued fraction expansion. Much less is known about cubic irrationals. We do not even know if the partial quotients are bounded, even though extensive computations suggest they might follow Kuzmin&#39;s probability law. Results are given for sequences of partial quotients of $\sqrt[3]{m}$ and $\sqrt[3]{m^2}$ with $m

N. Grau

Fully reconstructed jets and direct photon-tagged jet fragments significantly reduce energy-loss bias, the bias toward mostly measuring particles from partons which suffer little energy loss. In d+Au collisions, one accesses the physics at large $x$, which yields important constraints for nuclear parton distribution functions. In both d+Au and A+A collisions

Xiang Leng, Javier Garcia-Barriocanal, Boyi Yang, Yeonbae Lee

We successfully tuned an underdoped ultrathin YBa2Cu3O7-x film into the overdoped regime by means of electrostatic doping using an ionic liquid as a dielectric material. This process proved to be reversible. Transport measurements showed a series of anomalous features compared to chemically doped bulk samples and a different two-step doping mechanism for ele

Vladimir Krouglov

The conjecture of D.Blair says that there are no nonflat Riemannian metrics of nonpositive curvature compatible with a contact structure. We prove this conjecture for a certain class of contact structures on closed 3-dimensional manifolds and construct a local counterexample. We also prove that a hyperbolic metric on $\mathbb{R}^3$ cannot be compatible with

Donatella Fiorucci, Orchidea Maria Lecian, Giovanni Montani

We analyze the features of the Minkowskian limit of a particular non-analytical f(R) model, whose Taylor expansion in the weak field limit does not hold, as far as gravitational waves (GWs) are concerned. We solve the corresponding Einstein equations and we find an explicit expression of the modified GWs as the sum of two terms, i.e. the standard one and a m

Mayank Mishra, Atul Mantri, Priyank Mishra, P. K. Panigrahi

A non-standard teleportation scheme is proposed, wherein probabilistic teleportation is achieved in conventionally non-teleporting channels. We make use of entanglement monogamy to incorporate an unknown state in a multipartite entangled channel, such that the receiver partially gets disentangled from the network. Subsequently, the sender performs local meas

Paulo M. Sá, Alfredo B. Henriques

We calculate the full spectrum, as observed today, of the cosmological gravitational waves generated within a model based on loop quantum cosmology. It is assumed that the universe, after the transition to the classical regime, undergoes a period of inflation driven by a scalar field with a chaotic-type potential. Our analysis shows that, for certain conditi

Luis Alvarez-Gaume, Ehsan Hatefi

We study the gravitational collapse of the axion-dilaton system suggested by type IIB string theory in dimensions ranging from four to ten. We extend previous analysis concerning the role played by the global SL(2,R) symmetry and we evaluate the Choptuik exponents in the elliptic case.

Wanfeng Yan, Reda Rebib, Ryan Woodard, Didier Sornette

Financial markets are well known for their dramatic dynamics and consequences that affect much of the world&#39;s population. Consequently, much research has aimed at understanding, identifying and forecasting crashes and rebounds in financial markets. The Johansen-Ledoit-Sornette (JLS) model provides an operational framework to understand and diagnose finan

Edoardo Ballico, Francesco Malaspina, Paolo Valabrega, Mario Valenzano

Let $E$ be an indecomposable rank two vector bundle on the projective space $\PP^n, n \ge 3$, over an algebraically closed field of characteristic zero. It is well known that $E$ is arithmetically Buchsbaum if and only if $n=3$ and $E$ is a null-correlation bundle. In the present paper we establish an analogous result for rank two indecomposable arithmetical

Susanne Ditlevsen, Priscilla Greenwood

We show that the stochastic Morris-Lecar neuron, in a neighborhood of its stable point, can be approximated by a two-dimensional Ornstein-Uhlenbeck (OU) modulation of a constant circular motion. The associated radial OU process is an example of a leaky integrate-and-fire (LIF) model prior to firing. A new model constructed from a radial OU process together w

Philippe Jacquet, Salman Malik, Bernard Mans, Alonso Silva

We study the scaling properties of a georouting scheme in a wireless multi-hop network of $n$ mobile nodes. Our aim is to increase the network capacity quasi linearly with $n$ while keeping the average delay bounded. In our model, mobile nodes move according to an i.i.d. random walk with velocity $v$ and transmit packets to randomly chosen destinations. The

A. Pukhov, N. Kumar, T. Tückmantel, A. Upadhyay

It is demonstrated that the performance of the self-modulated proton driver plasma wakefield accelerator (SM-PDPWA) is strongly affected by the reduced phase velocity of the plasma wave. Using analytical theory and particle-in-cell simulations, we show that the reduction is largest during the linear stage of self-modulation. As the instability nonlinearly sa

Wei Li, Hao Ding, Peng Deng, Kai Chang

Alkali-doped iron selenide is the latest member of high Tc superconductor family, and its peculiar characters have immediately attracted extensive attention. We prepared high-quality potassium-doped iron selenide (KxFe2-ySe2) thin films by molecular beam epitaxy and unambiguously demonstrated the existence of phase separation, which is currently under debate

Daniele Faccio, Iacopo Carusotto

Cavities with periodically oscillating mirrors have been predicted to excite photon pairs out of the quantum vacuum in a process known as the Dynamical Casimir effect. Here we propose and analyse an experimental layout that can provide an efficient modulation of the effective optical length of a cavity mode in the near-infrared spectral region. An analytical

H. T. Liu, J. M. Bai, J. M. Wang, S. K. Li

In this paper, a new method is proposed to estimate the broad-line region sizes of UV lines $R^{\rm{uv}}_{\rm{BLR}}$. It is applied to 3C 273. First, we derive the time lags of radio emission relative to broad emission lines Ly$α$ and C IV by the ZDCF method. The broad lines lag the 5, 8, 15, 22 and 37 GHz emission. The measured lags $τ^{\rm{uv}}_{\rm{ob}}$

Ondřej Bílka, Jozef Jirásek, Pavel Klavík, Martin Tancer

The problem Cover(H) asks whether an input graph G covers a fixed graph H (i.e., whether there exists a homomorphism G to H which locally preserves the structure of the graphs). Complexity of this problem has been intensively studied. In this paper, we consider the problem PlanarCover(H) which restricts the input graph G to be planar. PlanarCover(H) is polyn

Walter D Neumann

These are mostly expository notes based on the course of lectures on arithmetic invariants of hyperbolic manifolds given at the workshop associated with the final &#34;Volume Conference,&#34; held at Columbia University, June 2009. Some new results are included.

N. Thirumurugan, C. S. Sundar, A. Bharathi

Temperature dependent electrical resistivity and thermopower measurements were carried out on Gd1-xCaxBaCo2O5.53 with x varying between 0 and 0.25. Ca subsitution leads to the incorporation of holes (Co4+) into the system that leads to a reduction in resistivity and a stabilisation of the ferromagnetic phase at low temperatures. The temperature dependence of

Matthias Keller, Daniel Lenz, Simone Warzel

We study the spectrum of random operators on a large class of trees. These trees have finitely many cone types and they can be constructed by a substitution rule. The random operators are perturbations of Laplace type operators either by random potentials or by random hopping terms, i.e., perturbations of the off-diagonal elements. We prove stability of arbi

S. D. Buliga, V. I. Globina, Yu. N. Gnedin, T. M. Natsvlishvili

In this paper we determined values of a spin of central black holes of the intermediate masses in globular clusters. For determination of value of a spin we used the known relation between the kinetic power of the relativistic jet and observable radio-luminosity of the region near to a central black hole, and our estimates have based on the known Blandford-Z

Guo Liang, Qian Shou, Qi Guo

The optical spatial solitons with ellipse-shaped spots have generally been considered to be a result of either linear or nonlinear anisotropy. In this paper, we introduce a class of spiraling elliptic solitons in the nonlocal nonlinear media without both linear and nonlinear anisotropy. The spiraling elliptic solitons carry the orbital angular momentum, whic

Yasuhiro Tamayama, Toshihiro Nakanishi, Yasuhiro Wakasa, Tetsuo Kanazawa

We investigate a dynamically controllable electromagnetically induced transparency-like metamaterial. The unit structure of the metamaterial consists of a low-quality-factor resonator and a high-quality-factor resonator. The field gradient of the incident electromagnetic wave in the transverse direction induces coupling between these two types of resonators

Don Hadwin

If $k$ is an infinite cardinal, we say a C*-algebra $\mathcal{A}$ is residually less than $k$ dimensional, $R_{<k}D,$ if the family of representations of $\mathcal{A}$ on Hilbert spaces of dimension less than $k$ separates the points of $\mathcal{A}.$ We give characterizations of this property, and we show that if $\{\mathcal{A}_{i}:i\in I\} $ is a family of

Cristian Cazacu

We consider the Schrödinger operator $A_ł:=-\D -ł/|x|^2$, $ł\in \rr$, when the singularity is located on the boundary of a smooth domain $Ω\subset \rr^N$, $N\geq 1$ The aim of this Note is two folded. Firstly, we justify the extension of the classical Pohozaev identity for the Laplacian to this case. The problem we address is very much related to Hardy-Poinc

Jeaman Ahn, Sijong Kwak, YeongSeok Song

In this paper, we are interested in the generic initial ideals of \textit{singular} projective curves with respect to the graded lexicographic order. Let $C$ be a \textit{singular} irreducible projective curve of degree $d\geq 5$ with the arithmetic genus $ρ_a(C)$ in $\p^r$ where $r\ge 3$. If $M(I_C)$ is the regularity of the lexicographic generic initial id

Tetsuo Kanazawa, Yasuhiro Tamayama, Toshihiro Nakanishi, Masao Kitano

We investigate second harmonic (SH) generation in a doubly resonant metamaterial. We show that SH generation can be enhanced when the resonant condition is satisfied for the SH frequency as well as for the fundamental frequency. A unit cell of the doubly resonant metamaterial consists of two coupled resonators, one of which resonates at the fundamental frequ

K. Sasaki, K. Kato, Y. Tokura, T. Sogawa

The universality of $k$-dependent electron-photon and electron-phonon matrix elements is discussed for graphene nanoribbons and carbon nanotubes. An electron undergoes a change in wavevector in the direction of broken translational symmetry, depending on the light polarization direction. We suggest that this phenomenon originates from a microscopic feature o

Paul So, Ernest Barreto

We consider an infinite network of globally-coupled phase oscillators in which the natural frequencies of the oscillators are drawn from a symmetric bimodal distribution. We demonstrate that macroscopic chaos can occur in this system when the coupling strength varies periodically in time. We identify period-doubling cascades to chaos, attractor crises, and h

Scott Rodney

This article gives an existence theory for weak solutions of second order non-elliptic linear Dirichlet problems of the form {eqnarray} \nabla&#39;P(x)\nabla u +{\bf HR}u+{\bf S&#39;G}u +Fu &=& f+{\bf T&#39;g} \textrm{in}Θu&=&ϕ\textrm{on}\partial Θ.{eqnarray} The principal part $ξ&#39;P(x)ξ$ of the above equation is assumed to be comparable to a quadratic fo

Lei Fang, Xianwei Zhao, Yi-Hsin Chiu, Dongkyun Ko

The demonstration of strong photoluminescence polarization anisotropy in semiconducting nanowires embodies both technological promise and scientific challenge. Here we present progress on both fronts through the study of the photoluminescence polarization anisotropy of randomly oriented nanowire ensembles in materials without/with crystalline anisotropy, sma

Matilde Santos, Jose Antonio Martin H., Victoria Lopez, Guillermo Botella

In a Role-Playing Game, finding optimal trajectories is one of the most important tasks. In fact, the strategy decision system becomes a key component of a game engine. Determining the way in which decisions are taken (online, batch or simulated) and the consumed resources in decision making (e.g. execution time, memory) will influence, in mayor degree, the

M. Hassanzadeh, B. Rangipour

A new quantization of groupoids under the name of \times-Hopf coalgebras is introduced. We develop a Hopf cyclic theory with coefficients in stable-anti-Yetter-Drinfeld modules for \times-Hopf coalgebras. We use \times-Hopf coalgebras to study coextensions of coalgebras. Finally, equivariant \times-Hopf coalgebra Galois coextensions are defined and applied a

Satomi Kakiya, Kazutaka Kudo, Yoshihiro Nishikubo, Kenta Oku

We report superconductivity in novel iron-based compounds Ca10(PtnAs8)(Fe2-xPtxAs2)5 with n = 3 and 4. Both compounds crystallize in triclinic structures (space group P-1), in which Fe2As2 layers alternate with PtnAs8 spacer layers. Superconductivity with a transition temperature of 38 K is observed in the n = 4 compound with a Pt content of x ~ 0.36 in the

Rui Carvalho, Lubos Buzna, Wolfram Just, Dirk Helbing

This paper investigates the effect of network topology on the fair allocation of network resources among a set of agents, an all-important issue for the efficiency of transportation networks all around us. We analyse a generic mechanism that distributes network capacity fairly among existing flow demands. The problem can be solved by semi-analytical methods

Joshua D. Barr, Justin P. Bergfield, Charles A. Stafford

We develop a π-electron effective field theory (π-EFT) wherein the two-body Hamiltonian for a π-electron system is expressed in terms of three effective parameters: the π-orbital quadrupole moment, the on-site repulsion, and a dielectric constant. As a first application of this π-EFT, we develop a model of screening in molecular junctions based on image mult

Thomas J. Loredo, James O. Berger, David F. Chernoff, Merlise A. Clyde

We describe work in progress by a collaboration of astronomers and statisticians developing a suite of Bayesian data analysis tools for extrasolar planet (exoplanet) detection, planetary orbit estimation, and adaptive scheduling of observations. Our work addresses analysis of stellar reflex motion data, where a planet is detected by observing the &#34;wobble

Anna N. Morozovska, Eugene A. Eliseev, Maya D. Glinchuk, Long-Qing Chen

Theoretical analysis based on the Landau-Ginzburg-Devonshire (LGD) theory is used to show that the product effect of flexoelectricity and rotostriction can lead to a spontaneous polarization in the vicinity of antiphase boundaries, ferroelastic twin walls, surfaces and interfaces in the octahedrally tilted phase of otherwise non-ferroelectric perovskites suc

Karina Olszak, Zbigniew Olszak

It is proved that every concircularly recurrent manifold must be necessarily a recurrent manifold.

Narayan Prasad, Honghai Zhang, Hao Zhu, Sampath Rangarajan

We consider Multi-User MIMO (MU-MIMO) scheduling in the 3GPP LTE-Advanced (3GPP LTE-A) cellular uplink. The 3GPP LTE-A uplink allows for precoded multi-stream (precoded MIMO) transmission from each scheduled user and also allows flexible multi-user (MU) scheduling wherein multiple users can be assigned the same time-frequency resource. However, exploiting th

Subrahmanyam Kalyanasundaram, Asaf Shapira

A cycle C={v_1,v_2,....,v_1} in a tournament T is said to be even, if when walking along C, an even number of edges point in the wrong direction, that is, they are directed from v_{i+1} to v_i. In this short paper, we show that for every fixed even integer k >= 4, if close to half of the k-cycles in a tournament T are even, then T must be quasi-random. This

Hung Ngoc Nguyen, Hung P. Tong-Viet, Thomas P. Wakefield

Let $G$ be a finite group and let $cd(G)$ be the set of all irreducible complex character degrees of $G$. It was conjectured by Huppert in Illinois J. Math. 44 (2000) that, for every non-abelian finite simple group $H$, if $cd(G)=cd(H)$ then $G\cong H\times A$ for some abelian group $A$. In this paper, we confirm the conjecture for the family of projective s

Amadeo Irigoyen

We give here some precisions and improvements about the validity of the explicit reconstruction of any holomorphic function on a ball of $\mathbb{C}^2$ from its restrictions on a family of complex lines. Such validity depends on the mutual distribution of the lines. This condition can be geometrically described and is equivalent to a stronger stability of th

Jakub Mielczarek, Wlodzimierz Piechocki

We present results concerning propagation of the Gaussian state across the cosmological quantum bounce. The reduced phase space quantization of loop quantum cosmology is applied to the Friedman-Robertson-Walker universe with a free massless scalar field. Evolution of quantum moments of the canonical variables is investigated. The covariance turns out to be a