March 2013 arXiv papers — page 2

Hosam Abdo, Darko Dimitrov

The total irregularity of a graph $G$ is defined as $\irr_t(G)=1/2 \sum_{u,v \in V(G)}$ $|d_G(u)-d_G(v)|$, where $d_G(u)$ denotes the degree of a vertex $u \in V(G)$. In this paper we give (sharp) upper bounds on the total irregularity of graphs under several graph operations including join, lexicographic product, Cartesian product, strong product, direct pr

Naoya Miyazaki

In this article, we introduce symbol calculus on a projective scheme. Using holomorphic Poisson structures, we construct deformations of ring structures for structure sheaves on projective spaces.

Neri Merhav

Data processing lower bounds on the expected distortion are derived in the finite-alphabet semi-deterministic setting, where the source produces a deterministic, individual sequence, but the channel model is probabilistic, and the decoder is subjected to various kinds of limitations, e.g., decoders implementable by finite-state machines, with or without coun

Alexander A. Andrianov, Vladimir A. Andrianov, Oleg O. Novikov

A brief survey of fermion localization mechanism on a domain wall ("thick brane") generated by a topologically nontrivial vacuum configuration of scalar fields is given. The extension of scalar fields interaction with fermions which supplies fermions with an axial mass is proposed. For several flavors and generations of fermions this extension can en

Andrea Blunck, Hans Havlicek

We introduce and investigate an equivalence relation called "radical parallelism" on the projective line over a ring. It is closely related with the Jacobson radical of the underlying ring. As an application, we present a rather general approach to non-linear models of affine spaces and discuss some particular examples.

Frédéric Bayart, George Costakis

An important result of León-Saavedra and Müller says that the rotations of hypercyclic operators remain hypercyclic. We provide extensions of this result for orbits of operators which are rotated by unimodular complex numbers with polynomial phases. On the other hand, we show that this fails for unimodular complex numbers whose phases grow to infinity too qu

Thomas Mikosch, Olivier Wintenberger

We introduce the cluster index of a multivariate regularly varying stationary sequence and characterize the index in terms of the spectral tail process. This index plays a major role in limit theory for partial sums of regularly varying sequences. We illustrate the use of the cluster index by characterizing infinite variance stable limit distributions and pr

J. Dudouet, D. Juliani, M. Labalme, J. C. Angélique

During therapeutic treatment with heavier ions like carbon, the beam undergoes nuclear fragmentation and secondary light charged particles, in particular protons and alpha particles, are produced. To estimate the dose deposited into the tumors and the surrounding healthy tissues, the accuracy must be higher than ($\pm$3% and$\pm$1 mm). Therefore, measurement

Thibaut Capron, Guillaume Forestier, Angela Perrat-Mabilon, Christophe Peaucelle

We have measured Universal Conductance Fluctuations in the metallic spin glass Ag:Mn as a function of temperature and magnetic field. From this measurement, we can access the phase coherence time of the electrons in the spin glass. We show that this phase coherence time increases with both the inverse of the temperature and the magnetic field. From this we d

Pierre Calka, Nicolas Chenavier

A homogeneous Poisson-Voronoi tessellation of intensity $γ$ is observed in a convex body $W$. We associate to each cell of the tessellation two characteristic radii: the inradius, i.e. the radius of the largest ball centered at the nucleus and included in the cell, and the circumscribed radius, i.e. the radius of the smallest ball centered at the nucleus and

G. Giavaras, Neill Lambert, Franco Nori

We examine electronic transport in a spin-blockaded double quantum dot. We show that by tuning the strength of the spin-orbit interaction the current flowing through the double dot exhibits a dip at zero magnetic field or a peak at a magnetic field for which the two-electron energy levels anticross. This behaviour is due to the dependence of the singlet-trip

Pascal Auscher, Alan McIntosh, Andrew Morris

We establish new Calderón reproducing formulas for self-adjoint operators $D$ that generate strongly continuous groups with finite propagation speed. These formulas allow the analysing function to interact with $D$ through holomorphic functional calculus whilst the synthesising function interacts with $D$ through functional calculus based on the Fourier tran

Clément Charpentier, Eric Sopena

An incidence of a graph $G$ is a pair $(v,e)$ where $v$ is a vertex of $G$ and $e$ an edge incident to $v$. Two incidences $(v,e)$ and $(w,f)$ are adjacent whenever $v = w$, or $e = f$, or $vw = e$ or $f$. The incidence coloring game [S.D. Andres, The incidence game chromatic number, Discrete Appl. Math. 157 (2009), 1980-1987] is a variation of the ordinary

Pankaj Kumar, P. K. Manoharan

We present a multiwavelength study of the formation and ejection of a plasma blob and associated EUV waves in AR NOAA 11176, observed by SDO/AIA and STEREO on 25 March 2011. SDO/AIA images clearly show the formation and ejection of a plasma blob from the lower solar atmosphere at ~9 min prior to the onset of the M1.0 flare. This onset of the M-class flare ha

Nikolaj M. Glazunov

We review novel results and investigate actions and transformations of groups and semigroups on (quantum) spaces, present dynamical systems and zeta functions arising from these spaces, actions and transformations, discuss their stochastic properties.

A. Morassaei, F. Mirzapour, M. S. Moslehian

In this paper we investigate a notion of relative operator entropy, which develops the theory started by J.I. Fujii and E. Kamei [Math. Japonica 34 (1989), 341--348]. For two finite sequences $\mathbf{A}=(A_1,...,A_n)$ and $\mathbf{B}=(B_1,...,B_n)$ of positive operators acting on a Hilbert space, a real number $q$ and an operator monotone function $f$ we ex

M. S. Safronova, U. I. Safronova

Atomic properties of the 24 low-lying ns, np, nd, nf, and ng states in Th IV ion are calculated using the high-precision relativistic all-order method where all single, double, and partial triple excitations of the Dirac-Fock wave functions are included to all orders of perturbation theory. Recommended values are provided for a large number of electric-dipol

M. S. Moslehian, J. Micic, M. Kian

We present some generalized Jensen type operator inequalities involving sequences of self-adjoint operators. Among other things, we prove that if $f:[0,\infty) \to \mathbb{R}$ is a continuous convex function with $f(0)\leq 0$, then {equation*} \sum_{i=1}^{n} f(C_i) \leq f(\sum_{i=1}^{n}C_i)-δ_f\sum_{i=1}^{n}\widetilde{C}_i\leq f(\sum_{i=1}^{n}C_i) {equation*

Mohammad Ashekur Rahman, Atanu Barai, Md. Asadul Islam, M. M. A Hashem

We present a new integrated, portable device to provide a convenient solution for remote monitoring heart rate at the fingertip and body temperature using Ethernet technology and widely spreading internet. Now a days, heart related disease is rising. Most of the times in these cases, patients may not realize their actual conditions and even it is a common fa

N. Javaid, Z. A. Khan, U. Qasim, M. A. Khan

Wireless Multi-hop Networks (WMhNs) provide users with the facility to communicate while moving with whatever the node speed, the node density and the number of traffic flows they want, without any unwanted delay and/or disruption. This paper contributes Linear Programming models (LP_models) for WMhNs. In WMhNs, different routing protocols are used to facili

N. Javaid, U. Qasim, Z. A. Khan, M. A. Khan

In Wireless Multi-hop Networks (WMhNs), routing protocols with energy efficient and delay reduction techniques are needed to fulfill users demands. In this paper, we present Linear Programming models (LP_models) to assess and enhance reactive routing protocols. To practically examine constraints of respective LP_models over reactive protocols, we select AODV

Ajay Jasra, Anthony Lee, Christopher Yau, Xiaole Zhang

In the following article we develop a particle filter for approximating Feynman-Kac models with indicator potentials. Examples of such models include approximate Bayesian computation (ABC) posteriors associated with hidden Markov models (HMMs) or rare-event problems. Such models require the use of advanced particle filter or Markov chain Monte Carlo (MCMC) a

Thomas Ihle

An Enskog-like kinetic equation for self-propelled particles is solved numerically. I study a density instability near the transition to collective motion and find that while hydrodynamics breaks down, the kinetic approach leads to soliton-like supersonic waves with steep leading kinks and Knudsen numbers of order one. These waves show hysteresis, modify the

Paolo Novati, Maria Rosaria Russo

For the solution of linear discrete ill-posed problems, in this paper we consider the Arnoldi-Tikhonov method coupled with the Generalized Cross Validation for the computation of the regularization parameter at each iteration. We study the convergence behavior of the Arnoldi method and its properties for the approximation of the (generalized) singular values

Jörg P. Rachen, Ute G. Gahlings

Based on the cosmological results of the Planck Mission, we show that all parameters describing our Universe within the ΛCDM model can be constructed from a small set of numbers known from conspiracy theory. Our finding is confirmed by recent data from high energy particle physics. This clearly demonstrates that our Universe is a plot initiated by an unknown

Yann Grisel, Jérémie Fourbil, Vincent Mouysset

We are interested in the localization of defects in non-absorbing inhomogeneous media with far-field measurements generated by plane waves. In localization problems, most so-called sampling methods are based on a characterization involving point-sources and the range of some implicitly defined operator. We present here a way to deal with this implicit operat

Nabile Boussaid, Marco Caponigro, Thomas Chambrion

This paper provides rigorous definitions and analysis of the dynamics of weakly-coupled systems and gives sufficient conditions for an infinite dimensional quantum control system to be weakly-coupled. As an illustration we provide examples chosen among common physical systems.

Qi Lü

This paper is addressed to studying the exact controllability for stochastic transport equations by two controls: one is a boundary control imposed on the drift term and the other is an internal control imposed on the diffusion term. By means of the duality argument, this controllability problem can be reduced to an observability problem for backward stochas

Vassily Gorbounov, Maxim Smirnov

We study the possibility of constructing a Frobenius manifold for the standard Landau-Ginzburg model of odd-dimensional quadrics $Q_{2n+1}$ and matching it with the Frobenius manifold attached to the quantum cohomology of these quadrics. Namely, we show that the initial conditions of the quantum cohomology Frobenius manifold of the quadric can be obtained fr

Vincenzo De Leo, Giovanni Santoboni, Federica Cerina, Mario Mureddu

This work analyses methods for the identification and the stability under perturbation of a territorial community structure with specific reference to transportation networks. We considered networks of commuters for a city and an insular region. In both cases, we have studied the distribution of commuters' trips (i.e., home-to-work trips and viceversa).

Andrew Gainer-Dewar, Ira M. Gessel

Using the theory of combinatorial species, we compute the cycle index for bipartite graphs, which we use to count unlabeled bipartite graphs and bipartite blocks.

Jinwei Yang

We derive certain systems of differential equations for matrix elements of products and iterates of logarithmic intertwining operators among strongly graded generalized modules for a strongly graded conformal vertex algebra under suitable assumptions. Using these systems of differential equations, we verify the convergence and extension property needed in th

Ramy Hussein, Amr Mohamed

Wireless Electroencephalography (EEG) tele-monitoring systems performing encoding and streaming over energy-hungry wireless channels are limited in energy supply. However, excessive power consumption either in encoding or radio channel may render some applications inapplicable. Hence, energy efficient methods are needed to improve such applications. In this

Sergi Simon

This work explores the tensor and combinatorial constructs underlying the linearised higher-order variational equations of a generic autonomous system along a particular solution. The main result of this paper is a compact yet explicit and computationally amenable form for said variational systems and their monodromy matrices. Alternatively, the same methods

Elisabetta Chiodaroli, Camillo De Lellis, Ondrej Kreml

We consider the isentropic compressible Euler system in 2 space dimensions with pressure law $p(ρ) = ρ^2$ and we show the existence of classical Riemann data, i.e. pure jump discontinuities across a line, for which there are infinitely many admissible bounded weak solutions (bounded away from the void). We also show that some of these Riemann data are genera

Belle Collaboration, Z. Q. Liu, C. P. Shen, C. Z. Yuan

The cross section for $e^+ e^- \to π^+ π^- J/ψ$ between 3.8 GeV and 5.5 GeV is measured with a 967 fb$^{-1}$ data sample collected by the Belle detector at or near the $Υ(nS)$ ($n = 1,\ 2,\ ...,\ 5$) resonances. The Y(4260) state is observed, and its resonance parameters are determined. In addition, an excess of $π^+ π^- J/ψ$ production around 4 GeV is obser

Lisa Sundqvist, Kevin Keenan, Martin Zackrisson, Paulo Prodöhl

Understanding the population structure and patterns of gene flow within species is of fundamental importance to the study of evolution. In the fields of population and evolutionary genetics, measures of genetic differentiation are commonly used to gather this information. One potential caveat is that these measures assume gene flow to be symmetric. However,

Paul Ralph

It is widely accepted that understanding system requirements is important for software development project success. However, this paper presents two novel challenges to the requirements concept. First, where many plausible approaches to achieving a goal are evident, there may be insufficient overlap between approaches to form requirements. Second, while all

Susan J. Sierra, Chelsea Walton

This work is prompted by the long standing question of whether it is possible for the universal enveloping algebra of an infinite dimensional Lie algebra to be noetherian. To address this problem, we answer a 23-year-old question of Carolyn Dean and Lance Small; namely, we prove that the universal enveloping algebra of the Witt (or centerless Virasoro) algeb

K. V. Grigorishin, B. I. Lev

Generalization of a disordered metal's theory has been proposed when scattering of quasiparticles by impurities is caused with a retarded interaction. It was shown that in this case Anderson's theorem was violated in the sense that embedding of the impurities in s-wave superconductor increases its critical temperature. The increasing depends on param

Tamara Servi

We show how to solve explicitly an equation satisfied by a real function belonging to certain general quasianalytic classes. Examples of the classes under consideration are the collection of convergent generalised power series, a class of functions which contains some Dulac Transition Maps of real analytic planar vector fields, quasianalytic Denjoy-Carleman

Li-Feng Xi, Ying Xiong

In this paper, we study the question of classifying self-similar sets under bi-Lipschitz mappings and obtain an important bi-Lipschitz invariant, which is an ideal of a ring related to IFS. Roughly speaking, different Lipschitz equivalence classes of self-similar sets correspond to different ideal classes of a related ring. This result reveals an interesting

Diederik Aerts, Sandro Sozzo

We have recently presented a general scheme enabling quantum modeling of different types of situations that violate Bell's inequalities. In this paper, we specify this scheme for a combination of two concepts. We work out a quantum Hilbert space model where 'entangled measurements' occur in addition to the expected 'entanglement between the c

Kirti Joshi, Aleksandar Petrov

In this paper we determine the explicit structure of the semisimple part of the Hecke algebra that acts on Drinfeld modular forms of full level modulo T . We use computations of the Hecke action modulo T to find Drinfeld modular forms that cannot be eigenforms. Finally, we conjecture that the Hecke algebra that acts on Drinfeld modular forms of full level is

Diederik Aerts, Sandro Sozzo

We put forward a general classification for a structural description of the entanglement present in compound entities experimentally violating Bell's inequalities, making use of a new entanglement scheme that we developed recently. Our scheme, although different from the traditional one, is completely compatible with standard quantum theory, and enables

Hans Havlicek, Corrado Zanella

Let $\Gamma'$ and $\Gamma$ be two Grassmannians. The standard embedding $\phi:\Gamma'\times\Gamma\to \bar{P}$ is obtained by combining the Pl\"ucker and Segre embeddings. Given a further embedding $\eta: \Gamma'\times\Gamma \to P'$, we find a sufficient condition for the existence of $\alpha\in Aut(\Gamma)$ and of a collineation $\psi: \bar{P} \to P'$ such t

Andrea Blunck, Hans Havlicek

We discuss representations of the projective line over a ring $R$ with 1 in a projective space over some (not necessarily commutative) field $K$. Such a representation is based upon a $(K,R)$-bimodule $U$. The points of the projective line over $R$ are represented by certain subspaces of the projective space $P(K,U\times U)$ that are isomorphic to one of the

Hans Havlicek, Hanfried Lenz

We give a short proof for the existence of the small Witt design which is based on the projective plane of order three with one point deleted.

D. Milisavljevic, A. Soderberg, R. Margutti, M. Drout

We present optical and near-infrared observations of SN 2012au, a slow-evolving supernova (SN) with properties that suggest a link between subsets of energetic and H-poor SNe and superluminous SNe. SN 2012au exhibited conspicuous SN Ib-like He I lines and other absorption features at velocities reaching 2 x 10^4 km/s in its early spectra, and a broad light c

Alessandro Bichara, Hans Havlicek, Corrado Zanella

Let $\chi$ be a linear morphism of the product of two projective spaces $PG(n,F)$ and $PG(m,F)$ into a projective space. Let $\gamma$ be the Segre embedding of such a product. In this paper we give some sufficient conditions for the existence of an automorphism $\alpha$ of the product space and a linear morphisms of projective spaces $\phi$, such that $\gamm

Andrea Blunck, Hans Havlicek

We endow the set of complements of a fixed subspace of a projective space with the structure of an affine space, and show that certain lines of such an affine space are affine reguli or cones over affine reguli. Moreover, we apply our concepts to the problem of describing dual spreads. We do not assume that the projective space is finite-dimensional or pappi

Johannes Gmainer, Hans Havlicek

The nucleus of a Veronese variety is the intersection of all its osculating hyperplanes. Various authors have given necessary and sufficient conditions for the nucleus to be empty. We present an explicit formula for the dimension of this nucleus for arbitrary characteristic of the ground field. As a corollary, we obtain a dimension formula for that subspace

Andrea Blunck, Hans Havlicek

We introduce the chain geometry $\Sigma(K,R)$ over a ring $R$ with a distinguished subfield $K$, thus extending the usual concept where $R$ has to be an algebra over $K$. A chain is uniquely determined by three of its points, if, and only if, the multiplicative group of $K$ is normal in the group of units of $R$. This condition is not equivalent to $R$ being

Hans Havlicek

An elementary geometric proof for the existence of Witt's 5-(12,6,1) design is given.

Johannes Gmainer, Hans Havlicek

A $k$-nucleus of a normal rational curve in PG$(n,F)$ is the intersection over all $k$-dimensional osculating subspaces of the curve ($k\in\{-1,0,...,n-1\}$). It is well known that for characteristic zero all nuclei are empty. In case of characteristic $p>0$ and $# F\geq n$ the number of non-zero digits in the representation of $n+1$ in base $p$ equals the n

Krishnendu Chatterjee, Jakub Łącki

We consider two core algorithmic problems for probabilistic verification: the maximal end-component decomposition and the almost-sure reachability set computation for Markov decision processes (MDPs). For MDPs with treewidth $k$, we present two improved static algorithms for both the problems that run in time $O(n \cdot k^{2.38} \cdot 2^k)$ and $O(m \cdot \l

E. C. Aschenauer, A. Bazilevsky, K. Boyle, K. O. Eyser

This document summarizes recent achievements of the RHIC spin program and their impact on our understanding of the nucleon's spin structure, i.e. the individual parton (quark and gluon) contributions to the helicity structure of the nucleon and to understand the origin of the transverse spin phenomena. Open questions are identified and a suite of future

Elke-Caroline Aschenauer, Salvatore Fazio, Kresimir Kumericki, Dieter Mueller

Several observables for the deeply virtual Compton scattering process have been simulated in the kinematic regime of a proposed Electron-Ion Collider to explore the possible impact of such measurements for the phenomenological access of generalized parton distributions. In particular, emphasis is given to the transverse distribution of sea quarks and gluons

Himanshu Chakraborty, Alok Shukla

Several years back Angliker et al [Chem. Phys. Lett. 1982, 87, 208] predicted nonacene to be the first linear acene with the triplet state $1^{3}B_{2u}$ as the ground state, instead of the singlet $1^{1}A_{g}$ state. However, contrary to that prediction, in a recent experimental work Tönshoff and Bettinger [ Angew. Chem. Int. Ed. 2010, 49, 4125] demonstrated

Sándor Krenedits, Szilárd Gy. Révész

We consider the extremal problem of maximizing a point value jf(z)j at a given point z 2 G by some positive definite and continuous function f on an Abelian group G, where for a given symmetric open set 3 z, f vanishes outside and is normalized by f(0) = 1. Denote the extremal value as CG(; z). This extremal problem was investigated in R and Rd and for a 0-s

Washington de Lima, Gustavo Camelo-Neto, Sérgio Coutinho

The spin-glass $q$-state Potts model on $d$-dimensional diamond hierarchical lattices is investigated by an exact real space renormalization group scheme. Above a critical dimension $d_l(q)$ for $q > 2$, the coupling constants probability distribution flows to a low-temperature \emph{strange attractor} or to the high-temperature paramagnetic fixed point, acc

Masakazu Muramatsu, Hayato Waki, Levent Tuncel

We consider a property of positive polynomials on a compact set with a small perturbation. When applied to a Polynomial Optimization Problem (POP), the property implies that the optimal value of the corresponding SemiDefinite Programming (SDP) relaxation with sufficiently large relaxation order is bounded from below by $(f^\ast - ε)$ and from above by $f^\as

Jason Greene Boynton, Jim Coykendall

It is well-known that the factorization properties of a domain are reflected in the structure of its group of divisibility. The main theme of this paper is to introduce a topological/graph-theoretic point of view to the current understanding of factorization in integral domains. We also show that connectedness properties in the graph and topological space gi

Qingjiang Shi, Liang Liu, Weiqiang Xu, Rui Zhang

This paper studies a multi-user multiple-input single-output (MISO) downlink system for simultaneous wireless information and power transfer (SWIPT), in which a set of single-antenna mobile stations (MSs) receive information and energy simultaneously via power splitting (PS) from the signal sent by a multi-antenna base station (BS). We aim to minimize the to

Shenggang Ying, Yuan Feng, Nengkun Yu, Mingsheng Ying

This paper studies three kinds of long-term behaviours, namely reachability, repeated reachability and persistence, of quantum Markov chains (qMCs). As a stepping-stone, we introduce the notion of bottom strongly connected component (BSCC) of a qMC and develop an algorithm for finding BSCC decompositions of the state space of a qMC. As the major contribution

H. S. Karthik, Hemant Katiyar, Abhishek Shukla, T. S. Mahesh

A sequence of moments encode the corresponding probability distribution. Probing if quantum joint probability distribution can be retrieved from the associated set of moments -- realized in the sequential measurement of a dichotomic observable at different time intervals -- reveals a negative answer i.e., the joint probabilities of sequential measurements do

Pedro A Guil Asensio, Ashish K. Srivastava

Warfield proved that every injective module has the exchange property. This was generalized by Fuchs who showed that quasi-injective modules satisfy the exchange property. We extend this further and prove that a module invariant under automorphisms of its injective hull satisfies the exchange property. We also show that automorphism-invariant modules are cle

Aleksey Korobenko, Alexander A. Milner, Valery Milner

Extremely fast rotating molecules carrying significantly more energy in their rotation than in any other degree of freedom are known as "super rotors". It has been speculated that super rotors may exhibit a number of unique properties. Theoretical studies showed that ultrafast molecular rotation may change the character of molecular scattering from s

Turlough Neary, Damien Woods, Niall Murphy, Rainer Glaschick

In the 1960's Gisbert Hasenjaeger built Turing Machines from electromechanical relays and uniselectors. Recently, Glaschick reverse engineered the program of one of these machines and found that it is a universal Turing machine. In fact, its program uses only four states and two symbols, making it a very small universal Turing machine. (The machine has t

Peter Keevash, John Lenz, Dhruv Mubayi

In this paper we consider spectral extremal problems for hypergraphs. We give two general criteria under which such results may be deduced from `strong stability' forms of the corresponding (pure) extremal results. These results hold for the α-spectral radius defined using the α-norm for any α>1; the usual spectrum is the case α=2. Our results imply that

F. Foukalas, G. T. Karetsos

We study the performance of cognitive radio networks (CRNs) when incorporating adaptive modulation at the physical layer. Three types of CRNs are considered, namely opportunistic spectrum access (OSA), spectrum sharing (SS) and sensing-based SS. We obtain closed-form expressions for the average spectral efficiency achieved at the secondary network and the op

Shan Gao

Energy nonconservation is a serious problem of dynamical collapse theories. In this paper, we propose a discrete model of energy-conserved wavefunction collapse. It is shown that the model is consistent with existing experiments and our macroscopic experience.

Soumya C. Kambhampati, Thomas Liu

A fundamental question in Computer Science is understanding when a specific class of problems go from being computationally easy to hard. Because of its generality and applications, the problem of Boolean Satisfiability (aka SAT) is often used as a vehicle for investigating this question. A signal result from these studies is that the hardness of SAT problem

T. Frolov, Y. Mishin

We present a thermodynamic theory of plane coherent solid-solid interfaces in multicomponent systems subject to nonhydrostatic mechanical stresses. The interstitial and substitutional chemical components are treated separately using chemical potentials and diffusion potentials, respectively. All interface excess quantities are derived using Cahns (1979) gene

Christopher Davis, Tommy Occhipinti

We prove there is no ring with unit group isomorphic to S_n for n \geq 5 and that there is no ring with unit group isomorphic to A_n for n \geq 5, n \neq 8. We give examples of rings with unit groups isomorphic to S_1, S_2, S_3, S_4, A_1, A_2, A_3, A_4, and A_8. We expect our methods to work similarly for other groups with trivial center; in particular, we p

F. Foukalas, T. Khattab, H. V. Poor

Cognitive relaying has been introduced for opportunistic spectrum access systems by which a secondary node forwards primary packets whenever the primary link faces an outage condition. For spectrum sharing systems, cognitive relaying is parametrized by an interference power constraint level imposed on the transmit power of the secondary user. For sensing-bas

P. Esquinazi, W. Hergert, D. Spemann, A. Setzer

In the last years the number of nominally non-magnetic solids showing magnetic order induced by some kind of defects has increased continuously. From the single element material graphite to several covalently bonded non-magnetic compounds, the influence of defects like vacancies and/or non-magnetic ad-atoms on triggering magnetic order has attracted the inte

Gibor Basri, Lucianne Walkowicz, Ansgar Reiners

We utilize Kepler data to study the precision differential photometric variability of solar-type and cooler stars at different timescales, ranging from half an hour to 3 months. We define a diagnostic that characterizes the median differential intensity change between data bins of a given timescale. We apply the same diagnostics to SOHO data that has been re

M. K. McClure, N. Calvet, C. Espaillat, L. Hartmann

Using NASA IRTF SpeX data from 0.8 to 4.5 $μ$m, we determine self-consistently the stellar properties and excess emission above the photosphere for a sample of classical T Tauri stars (CTTS) in the Taurus molecular cloud with varying degrees of accretion. This process uses a combination of techniques from the recent literature as well as observations of weak

David J. Gaebler

Dilations of completely positive semigroups to endomorphism semigroups have been studied by numerous authors. Most existing dilation theorems involve a non-unital embedding, corresponding to the embedding of $B(H)$ as a corner of $B(K)$ for Hilbert spaces $H \subset K$. A 1986 paper of Jean-Luc Sauvageot shows how to achieve a unital dilation, but does not s

Shampa M. Ghosh, Nicholas D. Testa, Alexander W. Shingleton

Most ectotherms show an inverse relationship between developmental temperature and body size, a phenomenon known as the temperature size rule (TSR). Several competing hypotheses have been proposed to explain its occurrence. According to one set of views, the TSR results from inevitable biophysical effects of temperature on the rates of growth and differentia

Ming-Hao Liu

The quantum capacitance model is applied to obtain an exact solution for the space-resolved carrier density in a multigated doped graphene sheet at zero temperature, with quantum correction arising from the finite electron capacity of the graphene itself taken into account. The exact solution is demonstrated to be equivalent to the self-consistent Poisson-Di

Benjamin Withers

We construct inhomogeneous charged black branes in AdS, holographically dual to a phase at finite chemical potential with spontaneously broken translation invariance in one direction. These are obtained numerically, solving PDEs for the fully backreacted system. Fixing the periodicity scale, we find a second order phase transition to the inhomogeneous phase.

Michael R. Geller, Zhongyuan Zhou

We construct simplified quantum circuits for Shor's order-finding algorithm for composites N given by products of the Fermat primes 3, 5, 17, 257, and 65537. Such composites, including the previously studied case of 15, as well as 51, 85, 771, 1285, 4369,... have the simplifying property that the order of a modulo N for every base a coprime to N is a pow

A. Rubbia

The Liquid Argon Time Projection Chamber offers an innovative technology for a new class of massive detectors for rare-event detection. It is a precise tracking device that allows three-dimensional spatial reconstruction with mm-scale precision of the morphology of ionizing tracks with the imaging quality of a "bubble chamber", provides $dE/dx$ infor

A. Kh. Khudoyberdiyev, B. A. Omirov

In this paper we describe the infinitesimal deformations of null-filiform Leibniz superalgebras over a field of zero characteristic. It is known that up to isomorphism in each dimension there exist two such superalgebras $NF^{n,m}$. One of them is a Leibniz algebra (that is $m=0$) and the second one is a pure Leibniz superalgebra (that is $m\neq 0$) of maxim

Ernesto Estrada, Jose A. de la Pena

Let G be a graph with set of vertices 1,...,n and adjacency matrix A of size nxn. Let d(i,j)=d, we say that f_d:N->N is a d-function on G if for every pair of vertices i,j and k>=d, we have a_ij^(k)=f_d(k). If this function f_d exists on G we say that G is d-walk regular. We prove that G is d-walk regular if and only if for every pair of vertices i,j at dist

Semion K. Saikin, Alexander Eisfeld, Stéphanie Valleau, Alán Aspuru-Guzik

Organic molecules store the energy of absorbed light in the form of charge-neutral molecular excitations -- Frenkel excitons. Usually, in amorphous organic materials, excitons are viewed as quasiparticles, localized on single molecules, which diffuse randomly through the structure. However, the picture of incoherent hopping is not applicable to some classes

Prashanth Alluvada

In the XYZ color space, the subset of the tri-stimuli corresponding to spike-type (monochromatic) impingement of energy is the chromaticity cone, CC. Using a family of concentric spheres, we describe a nonlinear transformation over the CC and construct a bijection from the CC onto the flat plane. In the process, we open up the CC and view it as a chart on th

Miron Ya. Amusia, Larissa V. Chernysheva, Victor G. Yarzhemsky

It is demonstrated that recent experiments on ionization of 3p and 3s electrons in Ni film and solid body cannot be described in the frames of Hartree-Fock or the random phase approximation with exchange. The deviation is so big that from the theoretical side it requires inclusion of huge and yet not entirely understood effects. Perhaps, it requires also exp

E. E. Ferrero, S. Bustingorry, A. B. Kolton, A. Rosso

We discuss the universal dynamics of elastic interfaces in quenched random media. We focus in the relation between the rough geometry and collective transport properties in driven steady-states. Specially devised numerical algorithms allow us to analyze the equilibrium, creep, and depinning regimes of motion in minimal models. The relevance of our results fo

J. M. Dong, U. Lombardo, W. Zuo

The onset of the 3PF2 superfluid phase in high-density neutron matter is studied within the BCS framework with two and three body forces. Owing to the strong correlations the energy gap is so sizeably quenched as to demand to reconsider the role of superfluidity in neutron-star phenomena.

Andrei Afanasev, Carl E. Carlson, Asmita Mukherjee

Twisted photon states, or photon states with large ($> \hbar$) angular momentum projection in the direction of motion, can photoexcite atomic final states of differing quantum numbers. If the photon symmetry axis coincides with the center of an atom, there are known selection rules that require exact matching between the quantum numbers of the photon and the

Elisha Falbel, Jieyan Wang

We obtain a branched spherical CR structure on the complement of the figure eight knot with a given holonomy representation (called rho_2). There are essentially two boundary unipotent representations from the complement of the figure eight knot into PU(2,1), we call them rho_1 and rho_2. We make explicit some fundamental differences between these two repres

S. I. Bondarenko, A. A. Shablo, V. P. Koverya, Yusheng He

Amplification of a low frequency magnetic field from a dipole source by means of linear ferromagnetic concentrator of different dimensions (permalloy micro wire) has been investigated experimentally. The results obtained strengthen the validity of the analytical relation for amplification which allows for nonlinear dependence of the magnetic permeability upo

Shachar Shayovitz, Dan Raphaeli

Many satellite communication systems operating today employ low cost upconverters or downconverters which create phase noise. This noise can severely limit the information rate of the system and pose a serious challenge for the detection systems. Moreover, simple solutions for phase noise tracking such as PLL either require low phase noise or otherwise requi

Mario G. Silveirinha

We characterize the spatial optical solitons supported by arrays of metallic nanowires embedded in Kerr-type material. The array of nanowires is described using an effective medium model and is regarded as a continuous medium. It is shown that the conditions necessary for the formation of spatial-solitons are radically different in presence of the nanowires,

S. I. Bondarenko, A. A. Shablo, V. P. Koverya, D. Yu. Fomin

The value of a locally frozen magnetic field in a region with a diameter of 0.5 mm in a 0.5-mm-thick YBa2Cu3O7-x plate was investigated as a function of the excitation field (to 2x10^4 A/m), plate cooling mode (in the absence or presence of a field; i.e., zero-field cooling (ZFC) or field coupling (FC)), and local demagnetizing field. Analysis of the measure

Milos S. Kurilic, Boris Sobot

The games G_2 and G_3 are played on a complete Boolean algebra B in ω-many moves. At the beginning White picks a non-zero element p of B and, in the n-th move, White picks a positive p_n < p and Black chooses an i_n belonging to {0,1}. White wins G_2 iff liminf p_n^{i_n}=0 and wins G_3 iff \bigvee_{A\in [ω]^ω}\bigwedge_{n\in A}p_n^{i_n}=0. It is shown that W

Daniel A. Cogswell, Martin Z. Bazant

The basic physics of nucleation in solid \hl{single-crystal} nanoparticles is revealed by a phase-field theory that includes surface energy, chemical reactions and coherency strain. In contrast to binary fluids, which form arbitrary contact angles at surfaces, complete &#34;wetting&#34; by one phase is favored at binary solid surfaces. Nucleation occurs when