April 2015 arXiv papers — page 9

Robie A. Hennigar, David Kubiznak, Robert B. Mann, Nathan Musoke

By employing the new ultraspinning limit we construct novel classes of black holes with non-compact event horizons and finite horizon area and study their thermodynamics. Our ultraspinning limit can be understood as a simple generating technique that consists of three steps: i) transforming the known rotating AdS black hole solution to a special coordinate s

Eric R. Switzer, Tzu-Ching Chang, Kiyoshi W. Masui, Ue-Li Pen

Intensity mapping experiments survey the spectrum of diffuse line radiation rather than detect individual objects at high signal-to-noise. Spectral maps of unresolved atomic and molecular line radiation contain three-dimensional information about the density and environments of emitting gas, and efficiently probe cosmological volumes out to high redshift. In

M. Sanz, I. L. Egusquiza, R. Di Candia, H. Saberi

Entanglement is widely considered the cornerstone of quantum information and an essential resource for relevant quantum effects, such as quantum teleportation, quantum cryptography, or the speed-up of quantum computing, as in Shor's algorithm. However, up to now, there is no general characterization of entanglement for many-body systems. In this sense, i

Luca Salasnich

We study the power spectrum of a space-time dependent neural field which describes the average membrane potential of neurons in a single layer. This neural field is modelled by a dissipative integro-differential equation, the so-called Amari equation. By considering a small perturbation with respect to a stationary and uniform configuration of the neural fie

Viktor Novičenko

We study control of synchronization in weakly coupled oscillator networks by using a phase reduction approach. Starting from a general class of limit cycle oscillators we derive a phase model, which shows that delayed feedback control changes effective coupling strengths and effective frequencies. We derive the analytical condition for critical control gain,

Luca Salasnich

We study analytically and numerically the generation of shock waves in a quasi one-dimensional Bose-Einstein condensate (BEC) made of dilute and ultracold alkali-metal atoms. For the BEC we use an equation of state based on a 1D nonpolynomial Schrodinger equation (1D NPSE), which takes into account density modulations in the transverse direction and generali

Anton Leykin, Uli Walther

In this survey we discuss various aspects of the singularity invariants with differential origin derived from the $D$-module generated by $f^s$.

J. T. Batley, M. C. Rosamond, M. Ali, E. H. Linfield

The temperature dependence of the spin diffusion length typically reflects the scattering mechanism responsible for spin relaxation. Within non-magnetic metals it is reasonable to expect the Elliot-Yafet mechanism to play a role and thus the temperature dependence of the spin diffusion length might be inversely proportional to resistivity. In lateral spin va

Benjamin Bittner, Marco Bozzano, Roberto Cavada, Alessandro Cimatti

This paper describes the xSAP safety analysis platform. xSAP provides several model-based safety analysis features for finite- and infinite-state synchronous transition systems. In particular, it supports library-based definition of fault modes, an automatic model extension facility, generation of safety analysis artifacts such as Dynamic Fault Trees (DFTs)

Federico Brivio, Jarvist M. Frost, Jonathan M. Skelton, Adam J. Jackson

The hybrid halide perovskite CH3NH3PbI3 exhibits a complex structural behaviour, with successive transitions between orthorhombic, tetragonal and cubic polymorphs at ca. 165 K and 327 K. Herein we report first-principles lattice dynamics (phonon spectrum) for each phase of CH3NH3PbI3. The equilibrium structures compare well to solutions of temperature-depend

Gareth M. Tracey

It is proved in [21] that there is a constant $c$ such that each transitive permutation group of degree $d\ge 2$ can be generated by $\lfloor cd/\sqrt{\log{d}}\rfloor$ elements. In this paper, we explicitly estimate $c$.

Marco Autili, Paola Inverardi, Massimo Tivoli, David Garlan

Adaptation of software components is an important issue in Component Based Software Engineering (CBSE). Building a system from reusable or Commercial-Off-The-Shelf (COTS) components introduces a set of problems, mainly related to compatibility and communication aspects. On one hand, components may have incompatible interaction behavior. This might require to

Moritz Fuchs, Felix Krauß, Daniel Hetterich, Björn Trauzettel

We study a thermally induced spin flip of an electron spin located in a semiconductor quantum dot. This interesting effect arises from an intriguing interplay between the Zeeman coupling to an external magnetic field and the hyperfine interaction with the surrounding nuclear spins. By considering a minimal model, we explain the main mechanism driving this sp

Paul-Emile Paradan, Michèle Vergne

The purpose of the present paper is two-fold. First, we obtain a non-abelian localization theorem when M is any even dimensional compact manifold : following an idea of E. Witten, we deform an elliptic symbol associated to a Clifford bundle on M with a vector field associated to a moment map. Second, we use this general approach to reprove the [Q,R] = 0 theo

Atsuhira Nagano

In the theory of complex multiplication, it is important to construct class fields over CM fields. In this paper, we consider explicit $K3$ surfaces parametrized by Klein's icosahedral invariants. Via the periods and the Shioda-Inose structures of $K3$ surfaces, the special values of icosahedral invariants generate class fields over quartic CM fields. Mo

Atsuhira Nagano

Shimura curves are moduli spaces of abelian surfaces with quaternion multiplication. Models of Shimura curves are very important in number theory. Klein's icosahedral invariants $\mathfrak{A},\mathfrak{B}$ and $\mathfrak{C}$ give the Hilbert modular forms for $\sqrt{5}$ via the period mapping for a family of $K3$ surfaces. Using the period mappings for s

Valeriy I. Sbitnev

Physical vacuum is a special superfluid medium. Its motion is described by the Navier-Stokes equation having two slightly modified terms that relate to internal forces. They are the pressure gradient and the dissipation force because of viscosity. The modifications are as follows: (a) the pressure gradient contains an added term describing the pressure multi

Otokar Dragoun, Drahoslav Vénos

Although neutrinos are probably the most abundant particles of the universe their mass is not yet known. Oscillation experiments have proven that at least one of the neutrino mass states has m_{i}>0.05 eV while various interpretations of cosmological observations yielded an upper limit for the sum of neutrino masses \sum m_{i}<(0.14-1.7) eV. The searches for

John B. Little

We show how the theory of affine geometries over the ring ${\mathbb Z}/\langle q - 1\rangle$ can be used to understand the properties of toric and generalized toric codes over ${\mathbb F}_q$. The minimum distance of these codes is strongly tied to the collections of lines in the finite geometry that contain subsets of the exponent vectors of the monomials t

J. Reiter, E. J. Rhodes, A. G. Kosovichev, J. Schou

A new fitting methodology is presented which is equally well suited for the estimation of low-, medium-, and high-degree mode parameters from $m$-averaged solar oscillation power spectra of widely differing spectral resolution. This method, which we call the &#34;Windowed, MuLTiple-Peak, averaged spectrum&#34;, or WMLTP Method, constructs a theoretical profi

Imma Gálvez, Vassily Gorbounov, Zain Shaikh, Andrew Tonks

In his extension of W. Siegel&#39;s ideas on string quantization, N. Berkovits made several observations which deserve further study and development. Indeed, interesting accounts of this work have already appeared in the mathematical literature and in a different guise due to Avramov. In this paper we bridge between these three approaches, by providing a com

Hanjin Kim, Hoon Lee, Minki Ahn, Han-Bae Kong

In this paper, we investigate wireless powered communication network for OFDM systems, where a hybrid access point (H-AP) broadcasts energy signals to users in the downlink, and the users transmit information signals to the H-AP in the uplink based on an orthogonal frequency division multiple access scheme. We consider a fullduplex H-AP which simultaneously

N. de Jong, E. Frantzeskakis, B. Zwartsenberg, Y. K. Huang

Interfaces between a bulk-insulating topological insulator (TI) and metallic adatoms have been studied using high-resolution, angle-resolved and core-level photoemission. Fe, Nb and Ag were evaporated onto Bi1.5Sb0.5Te1.7Se1.3 (BSTS) surfaces both at room temperature and 38K. The coverage- and temperature-dependence of the adsorption and interfacial formatio

Igor A. Zinchenko, Peter Berczik, Eva K. Grebel, Leonid S. Pilyugin

We investigate the influence of stellar migration caused by minor mergers (mass ratio from 1:70 to 1:8) on the radial distribution of chemical abundances in the disks of Milky Way-like galaxies during the last four Gyr. A GPU-based pure N-body tree-code model without hydrodynamics and star formation was used. We computed a large set of mergers with different

Robin Haunschild, Lutz Bornmann, Loet Leydesdorff

The number of papers published in journals indexed by the Web of Science core collection is steadily increasing. In recent years, nearly two million new papers were published each year; somewhat more than one million papers when primary research papers are considered only (articles and reviews are the document types where primary research is usually reported

Philip M. Davis, Angela Cochran

Analyzing 13,455 journals listed in the Journal Citation Report (Thomson Reuters) from 1997 through 2013, we report that the mean cited half-life of the scholarly literature is 6.5 years and growing at a rate of 0.13 years per annum. Focusing on a subset of journals (N=4,937) for which we have a continuous series of half-life observations, 209 of 229 (91%) s

R. H. Parker, M. R. Dietrich, M. R. Kalita, N. D. Lemke

The radioactive radium-225 ($^{225}$Ra) atom is a favorable case to search for a permanent electric dipole moment (EDM). Due to its strong nuclear octupole deformation and large atomic mass, $^{225}$Ra is particularly sensitive to interactions in the nuclear medium that violate both time-reversal symmetry and parity. We have developed a cold-atom technique t

Yair Poleg, Ariel Ephrat, Shmuel Peleg, Chetan Arora

While egocentric video is becoming increasingly popular, browsing it is very difficult. In this paper we present a compact 3D Convolutional Neural Network (CNN) architecture for long-term activity recognition in egocentric videos. Recognizing long-term activities enables us to temporally segment (index) long and unstructured egocentric videos. Existing metho

Xin Yuan, Ricardo Henao, Ephraim L. Tsalik, Raymond J. Langley

We consider the problem of discriminative factor analysis for data that are in general non-Gaussian. A Bayesian model based on the ranks of the data is proposed. We first introduce a new {\em max-margin} version of the rank-likelihood. A discriminative factor model is then developed, integrating the max-margin rank-likelihood and (linear) Bayesian support ve

S. M. Gusein-Zade, I. Luengo, A. Melle-Hernández

There are (at least) two different approaches to define equivariant analogue of the Euler charateristic for a space with a finite group action. The first one defines it as an element of the Burnside ring of the group. The second approach emerged from physics and includes the orbifold Euler characteristic and its higher order versions. Here we suggest a way t

Holger J. Pletsch, Colin J. Clark

We present the results of precision gamma-ray timing measurements of the binary millisecond pulsar PSR J2339$-$0533, an irradiating system of &#34;redback&#34; type, using data from the Fermi Large Area Telescope. We describe an optimized analysis method to determine a long-term phase-coherent timing solution spanning more than six years, including a measure

Maria Donten-Bury, Maksymilian Grab

We investigate Cox rings of symplectic resolutions of quotients of $\mathbb{C}^{2n}$ by finite symplectic group actions. We propose a finite generating set of the Cox ring of a symplectic resolution and prove that under a condition concerning monomial valuations it is sufficient. Also, three 4-dimensional examples are described in detail. Generators of the (

Constantia Alexandrou, Krzysztof Cichy, Vincent Drach, Elena Garcia-Ramos

We report on our exploratory study for the direct evaluation of the parton distribution functions from lattice QCD, based on a recently proposed new approach. We present encouraging results using Nf = 2 + 1 + 1 twisted mass fermions with a pion mass of about 370 MeV. The focus of this work is a detailed description of the computation, including the lattice c

Emanuele Frittaion, Matt Hendtlass, Alberto Marcone, Paul Shafer

A quasi-order $Q$ induces two natural quasi-orders on $P(Q)$, but if $Q$ is a well-quasi-order, then these quasi-orders need not necessarily be well-quasi-orders. Nevertheless, Goubault-Larrecq showed that moving from a well-quasi-order $Q$ to the quasi-orders on $P(Q)$ preserves well-quasi-orderedness in a topological sense. Specifically, Goubault-Larrecq p

A. Adare, C. Aidala, N. N. Ajitanand, Y. Akiba

We present measurements from the PHENIX experiment of large parity-violating single spin asymmetries of high transverse momentum electrons and positrons from $W^\pm/Z$ decays, produced in longitudinally polarized $p$$+$$p$ collisions at center of mass energies of $\sqrt{s}$=500 and 510~GeV. These asymmetries allow direct access to the anti-quark polarized pa

BESIII Collaboration, M. Ablikim, M. N. Achasov, X. C. Ai

We report a measurement of the branching fraction of $ψ(3770)\toγχ_{c1}$ and search for the transition $ψ(3770)\rightarrow γχ_{c2}$ based on 2.92~fb$^{-1}$ of $e^+e^-$ data accumulated at $\sqrt{s}=3.773$~GeV with the BESIII detector at the BEPCII collider. The measured branching fraction of $ψ(3770) \rightarrow γχ_{c1}$ is $\mathcal B(ψ(3770) \rightarrow γχ

Javier Aramayona, Conchita Martínez-Pérez

We study the (virtual) indicability of the automorphism group $Aut(A_Γ)$ of the right-angled Artin group $A_Γ$ associated to a simplicial graph $Γ$. First, we identify two conditions -- denoted (B1) and (B2) -- on $Γ$ which together imply that $H^1(G, Z)=0$ for certain finite-index subgroups $G<Aut(A_Γ)$. On the other hand we will show that (B2) is equivalen

B. Ciardi, S. Inoue, F. B. Abdalla, K. Asad

We investigate the feasibility of detecting 21cm absorption features in the afterglow spectra of high redshift long Gamma Ray Bursts (GRBs). This is done employing simulations of cosmic reionization, together with the instrumental characteristics of the LOw Frequency ARray (LOFAR). We find that absorption features could be marginally (with a S/N larger than

Manuel Weber, Fakher F. Assaad, Martin Hohenadler

We use the continuous-time interaction expansion (CT-INT) quantum Monte Carlo method to calculate the phonon spectral function of the one-dimensional Holstein-Hubbard model at half-filling. Our results are consistent with a soft-mode Peierls transition in the adiabatic regime, and the existence of a central peak related to long-range order in the Peierls pha

H. Nakada

It was pointed out [Phys. Rev. C \textbf{91}, 021302(R)] that the isotope shifts of the Pb nuclei, the kink at $N=126$ in particular, can be well described by the Hartree-Fock-Bogolyubov calculations if a density-dependent LS interaction derived from the $3N$ interaction is incorporated. Effects of the density-dependence in the LS channel on the isotope shif

Jean-François Baget, Meghyn Bienvenu, Marie-Laure Mugnier, Swan Rocher

We consider existential rules (aka Datalog+) as a formalism for specifying ontologies. In recent years, many classes of existential rules have been exhibited for which conjunctive query (CQ) entailment is decidable. However, most of these classes cannot express transitivity of binary relations, a frequently used modelling construct. In this paper, we address

Danilo Lewanski, Alexandr Popolitov, Sergey Shadrin, Dimitri Zvonkine

We analyze Chiodo&#39;s formulas for the Chern classes related to the r-th roots of the suitably twisted integer powers of the canonical class on the moduli space of curves. The intersection numbers of these classes with psi-classes are reproduced via the Chekhov-Eynard-Orantin topological recursion. As an application, we prove that the Johnson-Pandharipande

Ben Berckmoes

We establish a compactness result in approach theory which we apply to obtain a generalization of Prokhorov&#39;s Theorem for the continuity approach structure.

K. Narayan

Following arXiv:1501.03019 [hep-th], we study de Sitter space and spherical subregions on a constant boundary Euclidean time slice of the future boundary in the Poincare slicing. We show that as in that case, complex extremal surfaces exist here as well: for even boundary dimensions, we isolate the universal coefficient of the logarithmically divergent term

Maxime Jacquet, Friedrich Koenig

A moving boundary separating two otherwise homogeneous regions of a dielectric is known to emit radiation from the quantum vacuum. An analytical framework based on the Hopfield model, describing a moving refractive index step in 1+1 dimensions for realistic dispersive media has been developed in [1]. We expand the use of this model to calculate explicitly sp

N. G. Fytas, A. Malakis, W. Selke, L. N. Shchur

We study the effect of interfacial phenomena in two-dimensional perfect and random (or disordered) $q$-state Potts models with continuous phase transitions, using, mainly, Monte Carlo techniques. In particular, for the total interfacial adsorption, the critical behavior, including corrections to scaling, are analyzed. The role of randomness is scrutinized. R

Stéphane Bijakowski

We study the geometry of unitary Shimura varieties without assuming the existence of an ordinary locus. We prove, by a simple argument, the existence of canonical subgroups on a strict neighborhood of the $μ$-ordinary locus (with an explicit bound). We then define the overconvergent modular forms (of classical weight), as well as the relevant Hecke operators

Ehtibar Dzhafarov, Ru Zhang, Janne Kujala

Most behavioral and social experiments aimed at revealing contextuality are confined to cyclic systems with binary outcomes. In quantum physics, this broad class of systems includes as special cases Klyachko-Can-Binicioglu-Shumovsky-type, Einstein-Podolsky-Rosen-Bell-type, and Suppes-Zanotti-Leggett-Garg-type systems. The theory of contextuality known as Con

Stéphane Bijakowski

We prove in this paper a classicality result for overconvergent modular forms on PEL Shimura varieties of type (A) or (C), without any ramification hypothesis. We use an analytic continuation method, which generalizes previous results in the unramified setting. We work with the rational model of the Shimura variety, and use an embedding into the Siegel varie

A. Pérez

We show that the Dirac quantum cellular automaton [Ann. Phys. 354 (2015) 244] shares many properties in common with the discrete-time quantum walk. These similarities can be exploited to study the automaton as a unitary process that takes place at regular time steps on a one-dimensional lattice, in the spirit of general quantum cellular automata. In this way

Fanrong Xu

Dark $Z$/dark photon ($Z&#39;$) is one candidate of dark force carrier, which helps to interpret the properties of dark matter (DM). Other than traditional studies of DM including direct detection, indirect detection and collider simulation, in this work we take flavor physics as a complementary approach to investigate the features of dark matter. We give an

Nobuyuki Yoshioka, Hiroyasu Matsuura, Masao Ogata

We discuss the relationship between the quantum Hall conductance and a fractal energy band structure, Hofstadter&#39;s butterfly, on a square lattice under a magnetic field. At first, we calculate the Hall conductance of Hofstadter&#39;s butterfly on the basis of the linear responce theory. By classifying the bands into some groups with a help of continued f

Gabriel E. Topp, Tobias Brandes, Gernot Schaller

We investigate the thermodynamics of simple (non-interacting) transport models beyond the scope of weak coupling. For a single fermionic or bosonic level -- tunnel-coupled to two reservoirs -- exact expressions for the stationary matter and energy current are derived from the solutions of the Heisenberg equations of motion. The positivity of the steady-state

Sándor Z. Kiss, Csaba Sándor

Let $A$ and $B$ be sets of nonnegative integers. For a positive integer $n$ let $R_{A}(n)$ denote the number of representations of $n$ as the sum of two terms from $A$. Let $\displaystyle s_{A}(x) = \max_{n \le x}R_{A}(n)$ and $\displaystyle d_{A,B}(x) = \max_{\hbox{t: $a_{t} \le x$ or $b_{t} \le x$}}|a_{t} - b_{t}|$. In this paper we study the connection be

M. Chabab, A. Lahbas, M. Oulne

In a recent work (Phys.Rev.C84, 044321, 2011) M.J. Ermamatov and P.R. Fraser have studied rotational and vibrational excited states of axially symmetric nuclei within the Bohr Hamiltonian with different mass parameters. However, the energy formula that the authors have used contains some inaccuracies. So, the numerical results they obtained seem to be contro

Shingo Kobayashi, Masatoshi Sato

Dirac semimetals host bulk band-touching Dirac points and a surface Fermi loop. We develop a theory of superconducting Dirac semimetals. Establishing a relation between the Dirac points and the surface Fermi loop, we clarify how the nontrivial topology of Dirac semimetals affects their superconducting state. We note that the unique orbital texture of Dirac p

Min-Young Lee, Snezana Stanimirovic, Claire E. Murray, Carl Heiles

We investigate the impact of high optical depth on the HI saturation observed in the Perseus molecular cloud by using Arecibo HI emission and absorption measurements toward 26 radio continuum sources. The spin temperature and optical depth of individual HI components are derived along each line-of-sight, enabling us to estimate the correction for high optica

Kokin Nakajin, Shuichi Murakami

Surface states in Tl/Si(111) and Bi/Si(111) show non-Rashba-type spin splitting. We study spin-transport properties in these surface states. First we construct tight-binding Hamiltonians for Tl/Si and Bi/Si surfaces, which respect crystallographic symmetries. As a result, we find specific terms in the Tl/Si surface Hamiltonian responsible for non-Rashba spin

Nicola Tamanini

An interaction between dark matter and dark energy is usually introduced by a phenomenological modification of the matter conservation equations, while the Einstein equations are left unchanged. Starting from some general and fundamental considerations, in this work it is shown that a coupling in the dark sector is likely to introduce new terms also in the g

Ibrahim Kirat, Ilker Kocyigit

Suppose that the set ${\mathcal{T}}= \{T_1, T_2,...,T_q \} $ of real $n\times n$ matrices has joint spectral radius less than $1$. Then for any digit set $ D= \{d_1, \cdots, d_q\} \subset {\Bbb R}^n$, there exists a unique nonempty compact set $F=F({\mathcal{T}},D)$ satisfying $ F = \bigcup _{j =1}^q T_j(F + d_j)$, which is called a self-affine fractal. We c

A. P. Solon, M. E. Cates, J. Tailleur

Active Brownian particles (ABPs) and Run-and-Tumble particles (RTPs) both self-propel at fixed speed $v$ along a body-axis ${\bf u}$ that reorients either through slow angular diffusion (ABPs) or sudden complete randomisation (RTPs). We compare the physics of these two model systems both at microscopic and macroscopic scales. Using exact results for their st

Farida Enikeeva, Axel Munk, Frank Werner

We analyze the effect of a heterogeneous variance on bump detection in a Gaussian regression model. To this end we allow for a simultaneous bump in the variance and specify its impact on the difficulty to detect the null signal against a single bump with known signal strength. This is done by calculating lower and upper bounds, both based on the likelihood r

Piotr Micek, Veit Wiechert

We show that posets of bounded height whose cover graphs exclude a fixed graph as a topological minor have bounded dimension. This result was already proven by Walczak. However, our argument is entirely combinatorial and does not rely on structural decomposition theorems. Given a poset with large dimension but bounded height, we directly find a large clique

Kyeong-Hun Kim, Sungbin Lim

Let $p(t,x)$ be the fundamental solution to the problem $$ \partial_{t}^αu=-(-Δ)^βu, \quad α\in (0,2), \, β\in (0,\infty). $$ In this paper we provide the asymptotic behaviors and sharp upper bounds of $p(t,x)$ and its space and time fractional derivatives $$ D_{x}^{n}(-Δ_x)^γD_{t}^σI_{t}^δp(t,x), \quad \forall\,\, n\in\mathbb{Z}_{+}, \,\, γ\in[0,β],\,\, σ,

Thomas Le Goff, Paolo Politi, Olivier Pierre-Louis

We discuss the nonlinear dynamics and fluctuations of interfaces with bending rigidity under the competing attractions of two walls with arbitrary permeabilities. This system mimics the dynamics of confined membranes. We use a two-dimension hydrodynamic model, where membranes are effectively one-dimensional objects. In a previous work [T. Le Goff et al, Phys

Peng Tian, Hourong Qin

In this paper, we generalize D. H. Lehmer&#39;s result to give a sufficient condition for level one cusp forms $f$ with integral Fourier coefficients such that the smallest $n$ for which the coefficients $a_n(f)=0$ must be a prime. Then we describe a method to compute a bound $B$ of $n$ such that $a_n(f)\ne0$ for all $n<B$. As examples, we achieve the explic

A. Paolo Masucci, Elsa Arcaute, Erez Hatna, Kiril Stanilov

Urban morphology has presented significant intellectual challenges to mathematicians and physicists ever since the eighteenth century, when Euler first explored the famous Konigsberg bridges problem. Many important regularities and scaling laws have been observed in urban studies, including Zipf&#39;s law and Gibrat&#39;s law, rendering cities attractive sys

Thomas G. Wong

We formulate Grover&#39;s unstructured search algorithm as a chiral quantum walk, where transitioning in one direction has a phase conjugate to transitioning in the opposite direction. For small phases, this breaking of time-reversal symmetry is too small to significantly affect the evolution: the system still approximately evolves in its ground and first ex

Hong-Bin Chen, Jiun-Yi Lien, Guang-Yin Chen, Yueh-Nan Chen

In recent years, much effort has been devoted to the construction of a proper measure of quantum non-Markovianity. However, those proposed measures are shown to be at variance with different situations. In this work, we utilize the theory of $k$-positive maps to generalize a hierarchy of $k$-divisibility and develop a powerful tool, called $k$-divisibility p

M. Powalski, G. S. Uhrig, K. P. Schmidt

A quantitative description of magnons in long-range ordered quantum antiferromagnets is presented which is consistent from low to high energies. It is illustrated for the generic $S=1/2$ Heisenberg model on the square lattice. The approach is based on a continuous similarity transformation in momentum space using the scaling dimension as truncation criterion

Wen Huang, XiaoSheng Wu

In this work we prove that the set of the difference of primes is a $Δ_r^*$-set. The work is based on the recent dramatic new developments in the study of bounded gaps between primes, reached by Zhang, Maynard and Tao.

Jason D. Lotay, Yong Wei

We develop foundational theory for the Laplacian flow for closed G_2 structures which will be essential for future study. (1). We prove Shi-type derivative estimates for the Riemann curvature tensor Rm and torsion tensor T along the flow, i.e. that a bound on $Λ(x,t)=\left(|\nabla T(x,t)|_{g(t)}^2+|Rm(x,t)|_{g(t)}^2\right)^{\frac 12}$ will imply bounds on al

Marko Thiel

For an irreducible crystallographic root system $Φ$ and a positive integer $p$ relatively prime to the Coxeter number $h$ of $Φ$, we give a natural bijection $\mathcal{A}$ from the set $\widetilde{W}^p$ of affine Weyl group elements with no inversions of height $p$ to the finite torus $\check{Q}/p\check{Q}$. Here $\check{Q}$ is the coroot lattice of $Φ$. Thi

Prateep Chakraborty, Shreedevi K. Masuti

Let $G_{n,k}$ denote the complex Grassmann manifold of $k$-dimensional vector subspaces of $\mathbb{C}^n$. Assume $l,k\le \lfloor n/2\rfloor$. We show that, for sufficiently large $n$, any continuous map $h:G_{n,l}\to G_{n,k}$ is rationally null homotopic if $(i)~ 1\le k< l,$ $(ii)~2<l<k< 2(l-1)$, $(iii)~1<l<k$, $l$ divides $n$ but $l$ does not divide $k$.

Nazanin Dehghani, Masoud Asadpour

Twitter has become a leading source of real-time world-wide information and a great medium for exploring emerging events, breaking news and general topics which most matter to a broad audience. On the other hand, the explosive rate of incoming information in Twitter leads users to experience information overload. Whereas, a significant fraction of tweets are

Dieter Degrijse, Ian J. Leary

Let $G$ be an infinite discrete group and let $\underline{E}G$ be a classifying space for proper actions of $G$. Every $G$-equivariant vector bundle over $\underline{E}G$ gives rise to a compatible collection of representations of the finite subgroups of $G$. We give the first examples of groups $G$ with a cocompact classifying space for proper actions $\und

Shinji Mukohyama, Ryo Namba, Rio Saitou, Yota Watanabe

We study the nature of constraints and count the number of degrees of freedom in the nonprojectable version of the $U(1)$ extension of Hořava-Lifshitz gravity, using the standard method of Hamiltonian analysis in the classical field theory. This makes it possible for us to investigate the condition under which the scalar graviton is absent at a fully nonline

Oleg S. Ugolnikov, Boris V. Kozelov

The paper describes the observations and first results of studying the mesosphere temperature and dust based on twilight wide-field polarization analysis using original all-sky camera started in 2015 in Apatity, northern Russia (67.6 deg N, 33.4 deg E). It is the first twilight polarization measurements session conducted in the polar region and the first mea

Soyoung Jekal, S. H. Rhim, Soon Cheol Hong, Won-joon Son

Magnetism of FeRh (001) films strongly depends on film thickness and surface terminations. While magnetic ground state of bulk FeRh is G-type antiferromagnetism, the Rh-terminated films exhibit ferromagnetism with strong perpendicular MCA whose energy +2.1 meV/$\Box$ is two orders of magnitude greater than 3$d$ magnetic metals, where $\Box$ is area of two-di

Nicholas Proudfoot, Max Wakefield, Benjamin Young

We compute the Kazhdan-Lusztig polynomial of the uniform matroid of rank n-1 on n elements by proving that the i-th coefficient of is equal to the number of ways to choose i non-intersecting chords in an (n-i+1)-gon. We also show that the corresponding intersection cohomology group is isomorphic to the irreducible representation of the symmetric group associ

Gen Chiaki, Naoki Yoshida

We present a novel method for particle splitting in smoothed particle hydrodynamics simulations. Our method utilizes the Voronoi diagram for a given particle set to determine the position of fine daughter particles. We perform several test simulations to compare our method with a conventional splitting method in which the daughter particles are placed isotro

N. N. Achasov, A. V. Kiselev, G. N. Shestakov

The prediction of the cross section $σ(γγ^*(Q^2)\to ηπ^0)$ based on the simultaneous description of the Belle data on the $γγ\to ηπ^0$ reaction and the KLOE data on the $ϕ\toηπ^0γ$ decay is presented. The production of the scalar $a_0(980)$ and tensor $a_2(1320)$ is studied in detail. It is shown that the QCD based asymptotics of the $γ^*(Q^2)γ\to a_2(1320)\

Xueshi Guo, Nannan Liu, Xiaoying Li, Yuhong Liu

One of the important function in optical communication system is the distribution of information encoded in an optical beam. It is not a problem to accomplish this in a classical system since classical information can be copied at will. However, challenges arise in quantum system because extra quantum noise is often added when the information content of a qu

Julien Armijo, Raphaël Allio

We report the first observation of coherent back-scattering (CBS) of light in a transverse photonic disorder. The CBS peak is recorded in the far-field, at a fixed propagation time set by our crystal length, and displays a contrast approaching the ideal value of 1, which proves good coherence of transport in our system. We study its dynamics for increasing d

Bin Yang, Junjie Yan, Zhen Lei, Stan Z. Li

Deep learning methods are powerful tools but often suffer from expensive computation and limited flexibility. An alternative is to combine light-weight models with deep representations. As successful cases exist in several visual problems, a unified framework is absent. In this paper, we revisit two widely used approaches in computer vision, namely filtered

Robert Peters, Norio Kawakami

We demonstrate the existence of metallic spin density waves (SDWs) in the Kondo lattice model on a square lattice for a wide range of parameters by means of real space dynamical mean field theory. In these SDWs, the spin polarization as well as the charge density depend on the lattice site and are modulated along one direction of the square lattice. We show

Jian-hua Gao, Qun Wang

We demonstrate the emergence of the magnetic moment and spin-vorticity coupling of chiral fermions in 4-dimensional Wigner functions. In linear response theory with space-time varying electromagnetic fields, the parity-odd part of the electric conductivity can also be derived which reproduces results of the one-loop and the hard-thermal or hard-dense loop. A

Sean Gomes

The Laplace-Beltrami eigenfunctions on a compact Riemannian manifold $M$ whose geodesic billiard flow has mixed character have been conjectured by Percival to split into two complementary families, with all semiclassical mass supported in the completely integrable and ergodic regions of phase space respectively. In this paper, we consider the Dirichlet Lapla

Tamotsu Ikeda, Hidenori Katsurada

Let $B$ be a half-integral symmetric matrix of size $n$ defined over $\mathbb{Q}_p$. The Gross-Keating invariant of $B$ was defined by Gross and Keating, and has important applications to arithmetic geometry. But the nature of the Gross-Keating invariant was not understood very well for $n\geq 4$. In this paper, we establish basic properties of the Gross-Kea

Fernando Szechtman

Clifford theory of possibly infinite dimensional modules is studied

Hector Blandin

This work enrols the research line of M. Haiman on the Operator Theorem (the old operator conjecture). This theorem states that the smallest $\mathfrak{S}_n$-module closed under taking partial derivatives and closed under the action of polarization operators that contains the Vandermonde determinant is the space of diagonal harmonics polynomials. We start ge

Masahiko Ito, Masatoshi Noumi

We give an alternative proof of the evaluation formula for the elliptic Selberg integral of type $BC_n$ as an application of the fundamental $BC_n$-invariants.

V. P. Kiliyanpilakkil, S. Basu, A. Ruiz-Columbié, G. Araya

We have analyzed long-term wind speed time-series from five field sites up to a height of 300 m from the ground. Structure function-based scaling analysis has revealed that the scaling exponents in the mesoscale regime systematically depend on height. This anomalous behavior is likely caused by the buoyancy effects. In the framework of the extended self-simi

Ivan E. Cunha, Celso C. Barros

In this work, the Friedman equations for hadronic matter in the Robertson-Walker metric in the early Universe are obtained. We consider the hadronic phase, formed after the hadronization of the quark-gluon plasma, that means times from 10^{-6}s to 1s. The set of equations is derived and the behavior of the system is studied considering one approximate analyt

Ted Jacobson

Aristotelian electrodynamics (AE) describes the regime of a plasma with a very strong electric field that is not shorted out, with charge current determined completely by pair production and the balance of Lorentz 4-force against curvature radiation reaction. Here it is shown how the principal null directions and associated eigenvalues of the field tensor go

George M. Bergman, Pace P. Nielsen

Vaughan Pratt has introduced objects consisting of pairs $(A,W)$ where $A$ is a set and $W$ a set of subsets of $A,$ such that (i) $W$ contains $\emptyset$ and $A,$ (ii) if $C$ is a subset of $A\times A$ such that for every $a\in A,$ both $\{b\mid (a,b)\in C\}$ and $\{b\mid (b,a)\in C\}$ are members of $W$ (a &#34;crossword&#34; with all &#34;rows&#34; and &

T. Dauphinee, F. Marsiglio

The quantum mechanical behavior of a particle in a double well defies our intuition based on classical reasoning. Not surprisingly, an asymmetry in the double well will restore results more consistent with the classical picture. What is surprising, however, is how a very small asymmetry can lead to essentially classical behavior. In this paper we use the sim

Ying-Hui Shao, Gao-Feng Gu, Zhi-Qiang Jiang, Wei-Xing Zhou

The detrending moving average (DMA) algorithm is one of the best performing methods to quantify the long-term correlations in nonstationary time series. Many long-term correlated time series in real systems contain various trends. We investigate the effects of polynomial trends on the scaling behaviors and the performances of three widely used DMA methods in

Wenhong Tian, GuoZhong Li, Xinyang Wang, Qin Xiong

NP complete problem is one of the most challenging issues. The question of whether all problems in NP are also in P is generally considered one of the most important open questions in mathematics and theoretical computer science as it has far-reaching consequences to other problems in mathematics, computer science, biology, philosophy and cryptography. There

Debasish Bera, Sant S. Pathak, Indrajit Chakrabarty, George K. Karagiannidis

Modeling and analysis of cooperative spectrum sensing is an important aspect in cognitive radio systems. In this paper, the problem of energy detection (ED) of an unknown signal over Nakagami-$m$ fading is revisited. Specifically, an analytical expression for the local probability of detection is derived, while using the approach of ED at the individual seco