arXiv papers from April 2011

M. V. Movshev

We show that the space of gravitational spinors in eleven dimensions, defined by equations $\Gamma_{\alpha\beta}^i\lambda^{\alpha}\lambda^{\beta}=0$ admits a desingularization with nice geometric properties. In particular the desingularization fibers over the isotropic Grassmannian OGr(2,11). This enables us to recast equations of linearized eleven-dimension

Andrea Bernini, Vincenzo Venditti, Ottavia Spiga, Filippo Prischi

The surface accessibility of {\alpha}-bungarotoxin has been investigated by using Gd2L7, a newly designed paramagnetic NMR probe. Signal attenuations induced by Gd2L7 on {\alpha}-bungarotoxin C{\alpha}H peaks of 1H-13C HSQC spectra have been analyzed and compared with the ones previously obtained in the presence of GdDTPA-BMA. In spite of the different molec

The BABAR Collaboration, J. P. Lees

We analyze the decay B0-->K+ pi- pi0 with a sample of 454 million B Bbar events collected by the BaBar detector at the PEP-II asymmetric-energy B factory at SLAC, and extract the complex amplitudes of seven interfering resonances over the Dalitz plot. These results are combined with amplitudes measured in B0-->K_S pi+ pi- decays to construct isospin amplitud

Aditi Mitra, Thierry Giamarchi

An interaction quench in a Luttinger liquid can drive it into an athermal steady state. We analyze the effects on such an out of equilibrium state of a mode coupling term due to a periodic potential. Employing a perturbative renormalization group approach we show that even when the periodic potential is an irrelevant perturbation in equilibrium, it has impor

O. N. Sholukhova, S. N. Fabrika, A. V. Zharova, A. F. Valeev

(abridged) We present the results of studying the spectral and photometric variability of the luminous blue variable star V532 in M33. The photometric variations are traced from 1960 to 2010, spectral variations - from 1992 to 2009. The star has revealed an absolute maximum of visual brightness (1992-1994, high/cold state) and an absolute minimum (2007-2008,

Bruno Giacomazzo, Luciano Rezzolla, Nikolaos Stergioulas

We present new results on the dynamics and gravitational-wave emission from the collapse of differentially rotating neutron stars. We have considered a number of polytropic stellar models having different values of the dimensionless angular momentum J/M^2, where J and M are the asymptotic angular momentum and mass of the star, respectively. For neutron stars

Fionn Murtagh, Pedro Contreras

We survey agglomerative hierarchical clustering algorithms and discuss efficient implementations that are available in R and other software environments. We look at hierarchical self-organizing maps, and mixture models. We review grid-based clustering, focusing on hierarchical density-based approaches. Finally we describe a recently developed very efficient

Jared C. Workman, Eric G. Blackman, Chuang Ren

Magnetic reconnection is commonly perceived to drive flow and particle acceleration in flares of solar, stellar, and astrophysical disk coronae but the relative roles of different acceleration mecha- nisms in a given reconnection environment are not well understood. We show via direct numerical simulations that reconnection outflows produce weak fast shocks,

Mark M. Wilde, Patrick Hayden, Saikat Guha

The trade-off capacity region of a quantum channel characterizes the optimal net rates at which a sender can communicate classical, quantum, and entangled bits to a receiver by exploiting many independent uses of the channel, along with the help of the same resources. Similarly, one can consider a trade-off capacity region when the noiseless resources are pu

Alan Lindsay, Joceline Lega

Finite time singularity formation in a fourth order nonlinear parabolic partial differential equation (PDE) is analyzed. The PDE is a variant of a ubiquitous model found in the field of Micro-Electro Mechanical Systems (MEMS) and is studied on a one-dimensional (1D) strip and the unit disc. The solution itself remains continuous at the point of singularity w

J. A. Aguilar-Saavedra, N. F. Castro, A. Onofre

We use the recent measurements of top quark decay asymmetries in ATLAS and the t-channel single top cross section in CMS to set the first combined LHC limits on the Wtb vertex. This combination allows to obtain much better limits than the separate measurements. The resulting constraints are comparable, although still weaker, than the ones obtained using Teva

Chao Zhang, Pinyi Ren, Jingbo Peng, Guo Wei

In this paper, we propose an optimal relay power allocation of an Amplify-and-Forward relay networks with non-linear power amplifiers. Based on Bussgang Linearization Theory, we depict the non-linear amplifying process into a linear system, which lets analyzing system performance easier. To obtain spatial diversity, we design a complete practical framework o

R. L. Mkrtchyan, A. N. Sergeev, A. P. Veselov

For two different natural definitions of Casimir operators for simple Lie algebras we show that their eigenvalues in the adjoint representation can be expressed polynomially in the universal Vogel's parameters $\alpha, \beta, \gamma$ and give explicit formulae for the generating functions of these eigenvalues.

A. N. Alexandrov, V. M. Sliusar, V. I. Zhdanov

High amplification events (HAEs) are common phenomena in extragalactic gravitational lens systems (GLSs), where the multiple images of a distant quasar are observed through a foreground galaxy. There is a considerable brightness magnification in one of the quasar images during HAE. Grieger, Kayser, and Refsdal (1988) proposed to use HAEs to study the central

Christopher L. Douglas, Ciprian Manolescu

Bordered Floer homology associates to a parametrized oriented surface a certain differential graded algebra. We study the properties of this algebra under splittings of the surface. To the circle we associate a differential graded 2-algebra, the nilCoxeter sequential 2-algebra, and to a surface with connected boundary an algebra-module over this 2-algebra, s

Mario Maican

We study the moduli space of Gieseker semi-stable sheaves on the complex projective plane supported on sextic curves and having Euler characteristic one. We determine locally free resolutions of length one for all such sheaves. We decompose the moduli space into strata which occur naturally as quotients modulo actions of certain algebraic groups. In some cas

Wesley Pegden, Charles K. Smart

The Abelian sandpile growth model is a diffusion process for configurations of chips placed on vertices of the integer lattice $\mathbb{Z}^d$, in which sites with at least 2d chips {\em topple}, distributing 1 chip to each of their neighbors in the lattice, until no more topplings are possible. From an initial configuration consisting of $n$ chips placed at

Paula Pérez-Rubio, Stefan Sint, Shinji Takeda

The set-up of the QCD Schr\"odinger functional (SF) on the lattice with staggered quarks requires an even number of points $L/a$ in the spatial directions, while the Euclidean time extent of the lattice, $T/a$, must be odd. Identifying a unique renormalisation scale, $L=T$, is then only possible up to O($a$) lattice artefacts. In this article we study such l

Thomas Müller, Jörg Frauendiener

In a first course of general relativity it is usually quite difficult for students to grasp the concept of a geodesic. It is supposed to be straight (auto-parallel) and yet it 'looks' curved. In these situations it is very useful to have some explicit examples available which show the different behaviour of geodesics. In this paper we present the GeodesicVie

Jethro Van Ekeren

The study of twisted representations of graded vertex algebras is important for understanding orbifold models in conformal field theory. In this paper we consider the general set-up of a vertex algebra $V$, graded by $\G/\Z$ for some subgroup $\G$ of $\R$ containing $\Z$, and with a Hamiltonian operator $H$ having real (but not necessarily integer) eigenvalu

Pavel Chadima, Petr Harmanec, Philip D. Bennett, Brian Kloppenborg

A series of 353 red electronic spectra obtained between 1994 and 2010, and of 171 UBV photometric observations of the 2010 eclipse, were analyzed in an effort to better understand the eclipsing binary eps Aur. The main results follow. (1) We attempted to recover a spectrum of the companion by disentangling the observed spectra of the eps Aur binary failed, b

Sam Tobin-Hochstadt, David Van Horn

Problems in program analysis can be solved by developing novel program semantics and deriving abstractions conventionally. For over thirty years, higher-order program analysis has been sold as a hard problem. Its solutions have required ingenuity and complex models of approximation. We claim that this difficulty is due to premature focus on abstraction and p

Henry Jacobs, Hiroaki Yoshimura

Many mechanical systems are large and complex, despite being composed of simple subsystems. In order to understand such large systems it is natural to tear the system into these subsystems. Conversely we must understand how to invert this tearing. In other words, we must understand interconnection. Such an understanding has already successfully understood in

Liliana Puchuri Medina

Let $\mathcal{P}_4$ be the linear family of foliations of degree 4 in $\mathbb{P}^2$ given by A. Lins Neto, whose set of parameters with first integral $I_p(\mathcal{P}_4)$ is dense and countable. In this work, we will calculate explicitly the degree of the rational first integral of the foliations in this linear family, as a function of the parameter.

Sariel Har-Peled

We provide a simple proof of the existence of a planar separator by showing that it is an easy consequence of the circle packing theorem. We also reprove other results on separators, including: (A) There is a simple cycle separator if the planar graph is triangulated. Furthermore, if each face has at most $d$ edges on its boundary, then there is a cycle sepa

Nikodem J. Poplawski

We propose a simple mechanism that may explain the observed particle-antiparticle asymmetry in the Universe. In the Einstein-Cartan-Sciama-Kibble theory of gravity, the intrinsic spin of matter generates spacetime torsion. Classical Dirac fields in the presence of torsion obey the nonlinear Hehl-Datta equation which is asymmetric under a charge-conjugation t

Yichen Wang, Pinyi Ren, Qinghe Du, Chao Zhang

One of the major challenges in the medium access control (MAC) protocol design over cognitive Ad Hoc networks (CAHNs) is how to efficiently utilize multiple opportunistic channels, which vary dynamically and are subject to limited power resources. To overcome this challenge, in this paper we first propose a novel diversity technology called \emph{Multi-Chann

Asia Shapira, Noa Voloch-Bloch, Boris A. Malomed, Ady Arie

We report analytical solutions for spatial solitons supported by layers of a quadratically nonlinear material embedded into a linear planar waveguide. A full set of symmetric, asymmetric, and antisymmetric modes pinned to a symmetric pair of the nonlinear layers is obtained. The solutions describe a bifurcation of the subcritical type, which accounts for the

Qinghe Du, Yi Huang, Pinyi Ren, Chao Zhang

The time-varying feature of wireless channels usually makes the hard delay bound for data transmissions unrealistic to guarantee. In contrast, the statistically-bounded delay with a small violation probability has been widely used for delay quality-of-service (QoS) characterization and evaluation. While existing research mainly focused on the statistical-del

Christian Notthoff, Dirk Reuter, Andreas Wieck, Axel Lorke

The spectrally resolved Terahertz photoconductivity between two separately contacted edge-channels of a two-dimensional electron gas in the quantum Hall regime is investigated. We use a not-simply-connected sample geometry which is topologically equivalent to a Corbino disc. Due to the high sensitivity of our novel sample structure, a weak resonance situated

Alain Joye

This paper aims at presenting a few models of quantum dynamics whose description involves the analysis of random unitary matrices for which dynamical localization has been proven to hold. Some models come from physical approximations leading to effective descriptions of the dynamics of certain random systems that are popular in condensed matter theoretical p

Krzysztof Kutak

We overview some of theory and phenomenology aspects of high energy factorization. In the theory part we focus on basic equations of high energy factorization i.e. BFKL, CCFM, BK. In the phenomenology part we focus on forward-central jets correlations at Large Hadron Collider and on production of charged particles in HERA.

Michael Baake, Uwe Grimm

Mathematical diffraction theory is concerned with the analysis of the diffraction image of a given structure and the corresponding inverse problem of structure determination. In recent years, the understanding of systems with continuous and mixed spectra has improved considerably. Simultaneously, their relevance has grown in practice as well. In this context

Felipe Robledo-Padilla, Hugo Garcia-Compean

Spin precession for an EPR pair of spin-1/2 particles in equatorial orbits around a Kerr-Newman black hole is studied. Hovering observers are introduced to ensure fixed reference frames in order to perform the Wigner rotation. These observers also guarantee a reliable direction to compare spin states in rotating black holes. The velocity of the particle due

D. V. Dolgy, D. J. Kang, T. Kim, B. Lee

In this paper we give some interesting relationships between twisted (h,q)-Euler numbers and q-Berstein polynomnials by using fermionic p-adic q-integrals on Zp

J. Botsoa, T. Sauvage, M. -P. Adam, P. Desgardin

We studied the parameters to optimize the production of negatively-charged nitrogen-vacancy color centers (NV-) in type~1b single crystal diamond using proton irradiation followed by thermal annealing under vacuum. Several samples were treated under different irradiation and annealing conditions and characterized by slow positron beam Doppler-broadening and

Pierre-Loïc Méliot

In this paper, we review the representation theory of the infinite symmetric group, and we extend the works of Kerov and Vershik by proving that the irreducible characters of the infinite symmetric group always satisfy a central limit theorem. Hence, for any point of the Thoma simplex, the corresponding measures on the levels of the Young graph have a proper

A. Del Popolo

In the present paper, we study how the dark matter density profiles of dwarfs galaxies in the mass range $10^8-10^{10} M_{\odot}$ are modified by the interaction of the dwarf in study with the neighboring structures, and by changing baryon fraction in dwarfs. As already shown in Del Popolo (2009), the slope of density profile of inner halos flattens with dec

Isabella Masina

We combine the data from PAMELA and FERMI-LAT cosmic ray experiments by introducing a simple sum rule. This allows to investigate whether the lepton excess observed by these experiments is charge symmetric or not. We also show how the data can be used to predict the positron fraction at energies yet to be explored by the AMS-02 experiment.

Antonio Negretti, Philipp Treutlein, Tommaso Calarco

We review quantum information processing with cold neutral particles, that is, atoms or polar molecules. First, we analyze the best suited degrees of freedom of these particles for storing quantum information, and then we discuss both single- and two-qubit gate implementations. We focus our discussion mainly on collisional quantum gates, which are best suite

Sudhir R. Ghorpade, Trygve Johnsen, Arunkumar R. Patil, Harish K. Pillai

We describe the higher weights of the Grassmann codes $G(2,m)$ over finite fields ${\mathbb F}_q$ in terms of properties of Schubert unions, and in each case we determine the weight as the minimum of two explicit polynomial expressions in $q$.

Michael Coons, Jeffrey Shallit

Let w be a binary string and let a_w (n) be the number of occurrences of the word w in the binary expansion of n. As usual we let s(n) denote the Stern sequence; that is, s(0)=0, s(1)=1, and for n >= 1, s(2n)=s(n) and s(2n+1)=s(n)+s(n+1). In this note, we show that s(n) = a_1 (n) + \sum_{w in 1 (0+1)*} s([w bar]) a_{w1} (n) where w bar denotes the complement

A. Skopenkov

This note is purely expositional and is a complement to math review MR2730150 to the paper Bel'kov, S. I.; Korepanov, I. G. Matrix solution of the pentagon equation with anticommuting variables, Teoret. i Matemat. Fizika, 163:3 (2010), 513-528. The authors consider purely mathematical problems of finding an invariant of a 3-manifold and finding certain ident

N. Sandor, J. S. Bakos, Zs. Sörlei, G. P. Djotyan

We propose and analyze a scheme for "on demand" creation of coherent superposition of meta-stable states in a tripod-structured atom using frequency-chirped laser pulses. Negligible excitation of the atoms during the creation of the superposition states is a priority in our consideration. The underlying physics of the scheme is explained using the formalism

Joan A. Vaccaro

Symmetry plays a central role in many areas of modern physics. Here we show that it also underpins the dual particle and wave nature of quantum systems. We begin by noting that a classical point particle breaks translational symmetry whereas a wave with uniform amplitude does not. This provides a basis for associating particle nature with asymmetry and wave

R. Zhao-Geisler, A. Quirrenbach, R. Koehler, B. Lopez

Mid-infrared (8-13 microns) interferometric data of W Hya were obtained with MIDI/VLTI between April 2007 and September 2009, covering nearly three pulsation cycles. The spectrally dispersed visibility data of all 75 observations were analyzed by fitting a circular fully limb-darkened disk (FDD) model to all data and individual pulsation phases. Asymmetries

Tomoya Hirota, Takeshi Sakai, Nami Sakai, Satoshi Yamamoto

We have found two dense cores, CB130-3 and L673-SMM4, where the carbon-chain molecules are extremely abundant relative to NH$_{3}$, during a survey observation of radio emission lines of CCS, HC$_{3}$N, HC$_{5}$N, and NH$_{3}$ toward dark cloud cores. Judging from the low NH$_{3}$/CCS ratios, they are possible candidates for "Carbon-Chain--Producing Regions

Partha Roy Chowdhury

A pure nucleonic equation of state (EoS) for beta equilibrated charge neutral neutron star (NS) matter is determined using density dependent effective NN interaction. This EoS is found to satisfy both the constraints from the observed mass-radius of neutron stars and flow data from heavy-ion collisions. Recent observations of the binary millisecond pulsar J1

Azrulhizam Shapi'i, Riza Sulaiman, Mohammad Khatim Hasan, Abdul Yazid Mohd Kassim

Preoperative templating in Total Hip Replacement (THR) is a method to estimate the optimal size and position of the implant. Today, observational (manual) size recognition techniques are still used to find a suitable implant for the patient. Therefore, a digital and automated technique should be developed so that the implant size recognition process can be e

Tomislav Prokopec

It is well known that string theories naturally compactify on anti-de Sitter spaces, and yet cosmological observations show no evidence of a negative cosmological constant in the early Universe's evolution. In this letter we present two simple nonlocal modifications of the standard Friedmann cosmology that can lead to observationally viable cosmologies with

Hamid Mohammadzadeh, Behrouz Edalatzadeh

Similar to works of G. Ellis (1998), the concept of covering pair of Lie algebras is defined. Also, we show the existence of covering pair for the pair of Lie algebras (L,N) and then show that every crossed module is a homomorphic image of a covering pair of (L,N). Finally, under some condition, we present some inequalities for the Schur multiplier of a pair

Genqian Liu

Let $\Omega$ be a bounded domain with $C^\infty$ boundary in an $n$-dimensional $C^\infty$ Riemannian manifold, and let $\varrho$ be a non-negative bounded function defined on $\partial \Omega$. It is well-known that for the biharmonic equation $\Delta^2 u=0$ in $\Omega$ with the 0-Dirichlet boundary condition, there exists an infinite set $\{u_k\}$ of bihar

R. Hernandez, J. Sacristan, L. Asin, T. E. Torres

We report on novel ferrogels derived from polysaccharides (sodium alginate and chitosan) with embedded iron oxide nanoparticles synthesized in situ and their combination with thermally responsive poly (N-isopropylacrylamide) for externally-driven drug release using AC magnetic fields. Samples were characterized by Raman spectroscopy, transmission electron mi

Rajesh Sharma, Anwitaman Datta

Recent years have seen several earnest initiatives from both academic researchers as well as open source communities to implement and deploy decentralized online social networks (DOSNs). The primary motivations for DOSNs are privacy and autonomy from big brotherly service providers. The promise of decentralization is complete freedom for end-users from any s

Jinn-Ouk Gong, Hyun Min Lee

We consider a simple inflation model with a complex scalar field coupled to gravity non-minimally. Both the modulus and the angular directions of the complex scalar are slowly rolling, leading to two-field inflation. The modulus direction becomes flat due to the non-minimal coupling, and the angular direction becomes a pseudo-Goldstone boson from a small bre

Shunsuke Takagi

This paper presents three results on F-singularities. First, we give a new proof of Eisenstein's restriction theorem for adjoint ideal sheaves, using the theory of F-singularities. Second, we show that a conjecture of Musta\c{t}\u{a} and Srinivas implies a conjectural correspondence of F-purity and log canonicity. Finally, we prove this correspondence when t

Analia Zwick, Gonzalo A. Alvarez, Joachim Stolze, Omar Osenda

The transmission of quantum information between different parts of a quantum computer is of fundamental importance. Spin chains have been proposed as quantum channels for transferring information. Different configurations for the spin couplings were proposed in order to optimize the transfer. As imperfections in the creation of these specific spin-coupling d

Y. Yousefi, Kh. Kh. Muminov

It was studied coherent states in complex variables in SU(2), SU(3), SU(4) groups and in general in SU(n) group. Using the completeness relation of the coherent state, we obtain a path integral expression for transition amplitude which connects a pair of SU(n) coherent states. In the classical limit, a canonical equation of motion is obtained.

Guido Salvaneschi, Carlo Ghezzi, Matteo Pradella

Dynamic software adaptability is one of the central features leveraged by autonomic computing. However, developing software that changes its behavior at run time adapting to the operational conditions is a challenging task. Several approaches have been proposed in the literature to attack this problem at different and complementary abstraction levels: softwa

Lucia Caramellino, Giorgio Ferrari, Roberta Piersimoni

In the context of stochastic volatility models, we study representation formulas in terms of expectations for the power series' coefficients associated to the call price-function. As in a recent paper by Antonelli and Scarlatti the expansion is done w.r.t. the correlation between the noises driving the underlying asset price process and the volatility proces

Simone Pigolotti, Sebastian Bernhardsson, Jeppe Juul, Gorm Galster

In lowest unique bid auctions, $N$ players bid for an item. The winner is whoever places the \emph{lowest} bid, provided that it is also unique. We use a grand canonical approach to derive an analytical expression for the equilibrium distribution of strategies. We then study the properties of the solution as a function of the mean number of players, and comp

Roberto Soler, Jaume Terradas, Gary Verth, Marcel Goossens

It has been shown that resonant absorption is a robust physical mechanism to explain the observed damping of magnetohydrodynamic (MHD) kink waves in the solar atmosphere due to naturally occurring plasma inhomogeneity in the direction transverse to the direction of the magnetic field. Theoretical studies of this damping mechanism were greatly inspired by the

Bolivar Torres, Qing Pang, Gordon Skelton, Scott Bridges

The objective of this research is to integrate an RFID (Radio Frequency Identification) reader into a Wireless Sensor Network (WSN) to authorize or keep track of people carrying RFID tags. The objective was accomplished by integrating hardware and software. The hardware consisted of two WSN nodes - the RFID node connected to one of the WSN nodes, and a compu

Jérôme Chandesris, Alberto Dennunzio, Enrico Formenti, Luca Manzoni

This work studies some aspects of the computational power of fully asynchronous cellular automata (ACA). We deal with some notions of simulation between ACA and Turing Machines. In particular, we characterize the updating sequences specifying which are "universal", i.e., allowing a (specific family of) ACA to simulate any TM on any input. We also consider th

Takuma Tanaka, Toshio Aoyagi

Three-body interactions have been found in physics, biology, and sociology. To investigate their effect on dynamical systems, as a first step, we study numerically and theoretically a system of phase oscillators with three-body interaction. As a result, an infinite number of multistable synchronized states appear above a critical coupling strength, while a s

Pedro Bicudo, Nuno Cardoso, Marco Cardoso

We study the chiral crossover, the spectra of light-light and of static-light mesons and the deconfinement crossover at finite temperature T. Our framework is the confining and chiral invariant quark model, related to truncated Coulomb gauge QCD. Since we are dealing with light quarks, where the linear potential dominates the quark condensate and the spectru

Pierre Patie, Juan Carlos Pardo Milan, Mladen Savov

For a L\'evy process $\xi=(\xi_t)_{t\geq0}$ drifting to $-\infty$, we define the so-called exponential functional as follows \[{\rm{I}}_{\xi}=\int_0^{\infty}e^{\xi_t} dt.\] Under mild conditions on $\xi$, we show that the following factorization of exponential functionals \[{\rm{I}}_{\xi}\stackrel{d}={\rm{I}}_{H^-} \times {\rm{I}}_{Y}\] holds, where, $\times

Ishtiaq Ali, Natarajan Meghanathan

The interest in virtualization has been growing rapidly in the IT industry because of inherent benefits like better resource utilization and ease of system manageability. The experimentation and use of virtualization as well as the simultaneous deployment of virtual software are increasingly getting popular and in use by educational institutions for research

Romain Couillet, Merouane Debbah

For a long time, detection and parameter estimation methods for signal processing have relied on asymptotic statistics as the number $n$ of observations of a population grows large comparatively to the population size $N$, i.e. $n/N\to \infty$. Modern technological and societal advances now demand the study of sometimes extremely large populations and simult

Dongseok Kim, Young Soo Kwon, Jaeun Lee

Every link is shown to be presentable as a boundary of an unknotted flat banded surface. A (flat) banded link is defined as a boundary of an unknotted (flat) banded surface. A link's (flat) band index is defined as the minimum number of bands required to present the link as boundaries of an unknotted (flat) banded surface. Banded links of small (flat, respec

Natarajan Meghanathan

Communication protocols for mobile ad hoc networks (MANETs) follow either an Optimum Routing Approach (ORA) or the Least Overhead Routing Approach (LORA): With ORA, protocols tend to determine and use the optimal communication structure at every time instant; whereas with LORA, a protocol tends to use a chosen communication structure as long as it exists. In

Weiping Zhu

Loss tomography has been studied for more than 10 years and a number of estimators have been proposed. The estimators can be divided into two classes: maximum likelihood and non-maximum likelihood. The maximum likelihood estimators rely on the maximum likelihood principle to ensure the accuracy of the estimates obtained by the estimators. Unfortunately, all

Kien Trinh, Stephan Haas, Rong Yu, Tommaso Roscilde

We investigate the effects of quenched disorder, in the form of site and bond dilution, on the physics of the $S=1/2$ antiferromagnetic Heisenberg model on even-leg ladders. Site dilution is found to prune rung singlets and thus create localized moments which interact via a random, unfrustrated network of effective couplings, realizing a random-exchange Heis

Christopher R. Klein, Joseph W. Richards, Nathaniel R. Butler, Joshua S. Bloom

Interstellar dust presents a significant challenge to extending parallax-determined distances of optically observed pulsational variables to larger volumes. Distance ladder work at mid-infrared wavebands, where dust effects are negligible and metallicity correlations are minimized, have been largely focused on few-epoch Cepheid studies. Here we present the f

Weiping Zhu, Ke Deng

Loss tomography has received considerable attention in recent years and a number of estimators based on maximum likelihood (ML) or Bayesian principles have been proposed. Almost all of the estimators are devoted to the tree topology despite the general topology is more common in practice. There has been few likelihood function devoted to the general topology

Ting-Ting Wang, Shuang-Yan Yang, Chun-Fang Li

It is observed that a constant unit vector denoted by $\mathbf I$ is needed to characterize a complete orthonormal set of vector diffraction-free beams. The previously found diffraction-free beams are shown to be included as special cases. The $\mathbf I$-dependence of the longitudinal component of diffraction-free beams is also discussed.

Pablo D. Carrasco

According to the work of Dennis Sullivan, there exists a smooth flow on the 5-sphere all of whose orbits are periodic although there is no uniform bound on their periods. The question addressed in this article is whether these type of examples can occur in the partially hyperbolic context. That is, if does there exist a partially hyperbolic diffeomorphism of

Bao-Gang Hu

In this study, both Bayesian classifiers and mutual information classifiers are examined for binary classifications with or without a reject option. The general decision rules in terms of distinctions on error types and reject types are derived for Bayesian classifiers. A formal analysis is conducted to reveal the parameter redundancy of cost terms when abst

C. A. Dorso, P. A. Giménez Molinelli, J. A. López

Experiments with rare isotopes are shedding light on the role isospin plays in the equation of state (EoS) of nuclear matter, and isoscaling -an straight-forward comparison of reactions with different isospin- could deliver valuable information about it. In this work we test this assertion pragmatically by comparing molecular dynamics simulations of isoscali

Anup Patel, Niveeta Sharma, Magdalini Eirinaki

Data Security is a major issue in any web-based application. There have been approaches to handle intruders in any system, however, these approaches are not fully trustable; evidently data is not totally protected. Real world databases have information that needs to be securely stored. The approach of generating negative database could help solve such proble

Takahiro Ohgoe, Takahumi Suzuki, Naoki Kawashima

We study the checkerboard supersolid of the hard-core Bose-Hubbard model with the dipole-dipole interaction. This supersolid is different from all other supersolids found in lattice models in the sense that superflow paths through which interstitials or vacancies can hop freely are absent in the crystal. By focusing on repulsive interactions between intersti

Hajnal Andréka, István Németi, Gergely Székely

In this paper, we investigate the possibility of using closed timelike curves (CTCs) in relativistic hypercomputation. We introduce a wormhole based hypercomputation scenario which is free from the common worries, such as the blueshift problem. We also discuss the physical reasonability of our scenario, and why we cannot simply ignore the possibility of the

F. Y. Wang, Shi Qi, Z. G. Dai

Several interesting luminosity correlations among gamma-ray burst (GRB) variables have been recently discussed extensively. In this paper, we derive the six luminosity correlations ($\tlag-L$, $V-L$, $\epkk-L$, $\epkk-E_\gamma$, $\trt-L$, $\epkk-E_{\gamma, \mathrm{iso}}$) from the light curves and spectra of the latest 116 long GRBs, including the time lag (

I. Pascucci, M. Sterzik, R. D. Alexander, S. H. P. Alencar

Photoevaporation driven by the central star is expected to be a ubiquitous and important mechanism to disperse the circumstellar dust and gas from which planets form. Here, we present a detailed study of the circumstellar disk surrounding the nearby star TW Hya and provide observational constraints to its photoevaporative wind. Our new high-resolution (R ~ 3

J. Raja Jain, Dany-Sebastien Ly-Gagnon, Krishna C. Balram, Justin S. White

We present a method to fabricate tensile-strained germanium-on-insulator (GOI) substrates using heteroepitaxy and layer transfer techniques. The motivation is to obtain a high-quality wafer-scale GOI platform suitable for silicon-compatible optoelectronic device fabrication. Crystal quality is assessed using X-Ray Diffraction (XRD) and Transmission Electron

Mandeep Kaur Gondara, Sanjay Kadam

The importance of wireless communication is increasing day by day throughout the world due to cellular and broadband technologies. Everyone around the world would like to be connected seamlessly anytime anywhere through the best network. The 4G wireless system must have the capability to provide high data transfer rates, quality of services and seamless mobi

Agostino Capponi, Jose E. Figueroa-Lopez

We consider a portfolio optimization problem in a defaultable market with finitely-many economical regimes, where the investor can dynamically allocate her wealth among a defaultable bond, a stock, and a money market account. The market coefficients are assumed to depend on the market regime in place, which is modeled by a finite state continuous time Markov

Zhi-Gang Wang

In this article, we study the decays $\psi^{\prime}\to {J/\psi}\pi^+\pi^-$ and $\eta_c^{\prime}\to {\eta_c}\pi^+\pi^-$ by taking into account the chiral symmetry breaking effects, the final-state interactions and the heavy quark symmetry. We can confront the predictions of the $\eta_c^{\prime}\to \eta_c \pi^+\pi^-$ decay width and differential decay width wi

Parisa Gandomkar Yarandi, Krishna Mohan Gundu, Arash Mafi

The beam quality factor $M^2$ for the fundamental LP01 mode of a step-index fiber with a finite cladding diameter is calculated in the presence of gain, in a closed form, as a function of the complex generalized V-number. It is shown that the conventional infinite cladding diameter approximation cannot be used for index-antiguided gain-guided fibers, and the

R. C. Cotta, J. L. Hewett, A. Ismail, M. -P. Le

The generalization of the MSSM to the case of four chiral fermion generations (4GMSSM) can lead to significant changes in the phenomenology of the otherwise familiar Higgs sector. In most of the 3GMSSM parameter space, the lighter CP-even $h$ is $\sim 115-125$ GeV and mostly Standard Model-like while $H,A,H^\pm$ are all relatively heavy. Furthermore, the rat

Miao Li, Yi Pang

We propose to embed de Sitter space into five dimensional anti-de Sitter space to compute some physical quantities of interest, using the AdS/CFT correspondence. The static de Sitter can be considered as the conformal structure of the boundary of the hyperbolic AdS5 with a horizon, thus energy as well as entropy can be computed. The global dS can be embedded

Eoin Butler, Gorm. B. Andresen, Mohammad. D. Ashkezari, Marcelo Baquero-Ruiz

Spectroscopy of antihydrogen has the potential to yield high-precision tests of the CPT theorem and shed light on the matter-antimatter imbalance in the Universe. The ALPHA antihydrogen trap at CERN's Antiproton Decelerator aims to prepare a sample of antihydrogen atoms confined in an octupole-based Ioffe trap and to measure the frequency of several atomic t

Thomas Rothvoß

We prove that there are 0/1 polytopes P that do not admit a compact LP formulation. More precisely we show that for every n there is a sets X \subseteq {0,1}^n such that conv(X) must have extension complexity at least 2^{n/2 * (1-o(1))}. In other words, every polyhedron Q that can be linearly projected on conv(X) must have exponentially many facets. In fact,

Qinghe Du, Xi Zhang

We propose the QoS-aware BS-selection and the corresponding resource-allocation schemes for downlink multi-user transmissions over the distributed multiple-input-multiple-output (MIMO) links, where multiple location-independent base-stations (BS), controlled by a central server, cooperatively transmit data to multiple mobile users. Our proposed schemes aim a

Wenchi Cheng, Xi Zhang, Hailin Zhang

As a key in cognitive radio networks (CRNs), dynamic spectrum access needs to be carefully designed to minimize the interference and delay to the \emph{primary} (licensed) users. One of the main challenges in dynamic spectrum access is to determine when the \emph{secondary} (unlicensed) users can use the spectrum. In particular, when the secondary user is us

D. -G. Wang, J. J. Zhang, G. Zhuang

We construct and study a family of finitely generated Hopf algebra domains $H$ of Gelfand-Kirillov dimension two such that $\Ext^1_H(k,k)=0$. Consequently, we answer a question of Goodearl and the second-named author.

Yi Song, Jiang Xie

Cognitive radio (CR) technology is a promising solution to enhance the spectrum utilization by enabling unlicensed users to exploit the spectrum in an opportunistic manner. Since unlicensed users are temporary visitors to the licensed spectrum, they are required to vacate the spectrum when a licensed user reclaims it. Due to the randomness of the appearance

Yi Song, Jiang Xie

Cognitive radio (CR) technology is regarded as a promising solution to the spectrum scarcity problem. Due to the spectrum varying nature of CR networks, unlicensed users are required to perform spectrum handoffs when licensed users reuse the spectrum. In this paper, we study the performance of the spectrum handoff process in a CR ad hoc network under homogen

Tao Wang, Luc Vandendorpe

In relay-aided wireless transmission systems, one of the key issues is how to decide assisting relays and manage the energy resource at the source and each individual relay, to maximize a certain objective related to system performance. This paper addresses the sum rate maximized resource allocation (RA) problem in a point to point orthogonal frequency divis

Chen-Lung Hung, Xibo Zhang, Li-Chung Ha, Shih-Kuang Tung

We present a complete recipe to extract the density-density correlations and the static structure factor of a two-dimensional (2D) atomic quantum gas from in situ imaging. Using images of non-interacting thermal gases, we characterize and remove the systematic contributions of imaging aberrations to the measured density-density correlations of atomic samples