April 2015 arXiv papers — page 22

Debaprasad Maity

In this paper we propose a mechanism of natural preheating of our universe by introducing an inflaton field dependent mass term for the gravitational wave for a specific class of massive gravity theory. For any single field inflationary model, the inflaton must go through the oscillatory phase after the end of inflation. As has recently been pointed out, if

I. Necoara, Yu. Nesterov, F. Glineur

The standard assumption for proving linear convergence of first order methods for smooth convex optimization is the strong convexity of the objective function, an assumption which does not hold for many practical applications. In this paper, we derive linear convergence rates of several first order methods for solving smooth non-strongly convex constrained o

S. Robles, R. Domínguez-Tenreiro, J. Oñorbe, F. J. Martínez-Serrano

We present a detailed analysis of the local evolution of 206 Lagrangian Volumes (LVs) selected at high redshift around galaxy seeds, identified in a large-volume $Λ$ cold dark matter ($Λ$CDM) hydrodynamical simulation. The LVs have a mass range of $1 - 1500 \times 10^{10} M_\odot$. We follow the dynamical evolution of the density field inside these initially

Dominik R. G. Schleicher, Stefano Bovino, Muhammad A. Latif, Andrea Ferrara

Numerical simulations show the formation of self-gravitating primordial disks during the assembly of the first structures in the Universe, in particular during the formation of Pop.~III and supermassive stars. Their subsequent evolution is expected to be crucial to determine the mass scale of the first cosmological objects, which depends on the temperature o

M. A. Anacleto, F. A. Brito, E. Passos

In this paper we focus on the Hamilton-Jacobi method to determine the entropy of a self-dual black hole by using linear and quadratic GUPs(generalized uncertainty principles). We have obtained the Bekenstein-Hawking entropy of self-dual black holes and its quantum corrections that are logarithm and also of several other types.

Maryanthe Malliaris, Anand Pillay

We prove a regularity lemma with respect to arbitrary Keisler measures mu on V, nu on W where the bipartite graph (V,W,R) is definable in a saturated structure M and the formula R(x,y) is stable. The proof is rather quick and uses local stability theory. The special case where (V,W,R) is pseudofinite, mu, nu are the counting measures and M is suitably chosen

Alexander J. Mendez, Alison L. Coil, James Aird, Ramin A. Skibba

We measure the clustering of X-ray, radio, and mid-IR-selected active galactic nuclei (AGN) at 0.2 < z < 1.2 using multi-wavelength imaging and spectroscopic redshifts from the PRIMUS and DEEP2 redshift surveys, covering 7 separate fields spanning ~10 square degrees. Using the cross-correlation of AGN with dense galaxy samples, we measure the clustering scal

Monojit Ghosh, Pomita Ghoshal, Srubabati Goswami, Newton Nath

At present the three major unknowns in neutrino oscillation parameters are the mass hierarchy, the octant of $θ_{23}$ and the CP phase $δ_{CP}$. It is well known that the presence of hierarchy$-δ_{CP}$ and octant degeneracies affects the unambiguous determination of these parameters. In this paper we show that a comprehensive way to study the remaining param

Santiago Erroz-Ferrer, Johan H. Knapen, Ryan Leaman, Mauricio Cisternas

We present a kinematical study of 29 spiral galaxies included in the Spitzer Survey of Stellar Structure in Galaxies, using Halpha Fabry-Perot data obtained with the Galaxy Halpha Fabry-Perot System instrument at the William Herschel Telescope in La Palma, complemented with images in the R-band and in Halpha. The primary goal is to study the evolution and pr

Elena Kosygina, Jonathon Peterson

We consider a nearest-neighbor random walk on $\mathbb{Z}$ whose probability $ω_x(j)$ to jump to the right from site $x$ depends not only on $x$ but also on the number of prior visits $j$ to $x$. The collection $(ω_x(j))_{x\in\mathbb{Z},n\ge 0}$ is sometimes called the &#34;cookie environment&#34; due to the following informal interpretation. Upon each visit

Xin Lu, Kang Zuo

Let $f:\,S \to B$ be a locally non-trivial relatively minimal fibration of genus $g\geq 2$ with relative irregularity $q_f$. It was conjectured by Barja and Stoppino that the slope $λ_f\geq \frac{4(g-1)}{g-q_f}$. We prove the conjecture when $q_f$ is small with respect to $g$; we also construct counterexamples when $g$ is odd and $q_f=(g+1)/2$.

Wei Hu, Jinlong Yang

Research on graphene and other two-dimensional (2D) materials, such as silicene, germanene, phosphorene, hexagonal boron nitride (h-BN), graphitic carbon nitride (g-C3N4), graphitic zinc oxide (g-ZnO) and molybdenum disulphide (MoS2), has recently received considerable interest owing to their outstanding properties and wide applications. Looking beyond this

M. Trzebinski, P. Swierska

The process of jet-gap-jet (JGJ) production is briefly described. The JGJ scattering amplitude parametrisation is discussed. On the basis of full amplitude calculations, the parametrisation formulas for the leading logarithmic (LL) and next-to-leading logarithmic (NLL) approximations are obtained. For each case a sum over all conformal spins is considered. T

Zhentao Wang, Yoshitomo Kamiya, Andriy H. Nevidomskyy, Cristian D. Batista

We demonstrate that frustrated exchange interactions can produce exotic 3D crystals of vortex strings near the saturation field (H=Hsat) of body- and face-centered cubic Mott insulators. The combination of cubic symmetry and frustration leads to a magnon spectrum of the fully polarized spin state (H>Hsat) with degenerate minima at multiple noncoplanar Q vect

D. Choudhury, P. Rivero, D. Meyers, X. Liu

Using a combination of X-ray absorption spectroscopy experiments with first principle calculations, we demonstrate that insulating KCuO_2 contains Cu in an unusually-high formal-3+ valence state, the ligand-to-metal (O to Cu) charge transfer energy is intriguingly negative (Delta~ -1.5 eV) and has a dominant (~60%) ligand-hole character in the ground state a

N. Fayard, A. Cazé, R. Pierrat, R. Carminati

We study theoretically the spatial correlations between the intensities measured at the input and output planes of a disordered scattering medium. We show that at large optical thicknesses, a long-range spatial correlation persists and takes negative values. For small optical thicknesses, short-range and long-range correlations coexist, with relative weights

Reza Farrahi Moghaddam, Yves Lemieux, Mohamed Cheriet

In this work, the implications of new technologies, more specifically the new optical FTTH technologies, are studied both from the functional and non-functional perspectives. In particular, some direct impacts are listed in the form of abandoning non-functional technologies, such as micro-registration, which would be implicitly required for having a function

Santi Roca-Fàbrega, Octavio Valenzuela, Pedro Colín, Francesca Figueras

We introduce a new set of simulations of Milky Way-sized galaxies using the AMR code ART + hydrodynamics in a $Λ$CDM cosmogony. The simulation series is named GARROTXA and follow the formation of a halo/galaxy from z~$=$~60 to z~$=$~0. The final virial mass of the system is $\sim$7.4$\times$10$^{11}$M$_{\odot}$. Our results are as follows: (a) contrary to ma

Tiago Paixão, Jorge Pérez Heredia, Dirk Sudholt, Barbora Trubenová

Evolutionary algorithms (EAs) form a popular optimisation paradigm inspired by natural evolution. In recent years the field of evolutionary computation has developed a rigorous analytical theory to analyse their runtime on many illustrative problems. Here we apply this theory to a simple model of natural evolution. In the Strong Selection Weak Mutation (SSWM

M. Eschrig, A. Cottet, W. Belzig, J. Linder

Boundary conditions in quasiclassical theory of superconductivity are of crucial importance for describing proximity effects in heterostructures between different materials. Although they have been derived for the ballistic case in full generality, corresponding boundary conditions for the diffusive limit, described by Usadel theory, have been lacking for in

Carlos A. Alfaro, Hugo Corrales, Carlos E. Valencia

This paper studies critical ideals of graphs with twin vertices, which are vertices with the same neighbors. A pair of such vertices are called replicated if they are adjacent, and duplicated, otherwise. Critical ideals of graphs having twin vertices have good properties and show regular patterns. Given a graph $G=(V,E)$ and ${\bf d}\in \mathbb{Z}^{|V|}$, le

Sajna Hameed, Kavita Jain, Arul Lakshminarayan

We study the properties of the eigenvalues of real random matrices and their products. It is known that when the matrix elements are Gaussian-distributed independent random variables, the fraction of real eigenvalues tends to unity as the number of matrices in the product increases. Here we present numerical evidence that this phenomenon is robust with respe

B. Brecht, Dileep V. Reddy, C. Silberhorn, M. G. Raymer

Field-orthogonal temporal modes of photonic quantum states provide a new framework for quantum information science (QIS). They intrinsically span a high-dimensional Hilbert space and lend themselves to integration into existing single-mode fiber communication networks. We show that the three main requirements to construct a valid framework for QIS -- the con

Hector Zenil, Narsis A. Kiani, Jesper Tegnér

To cope with the complexity of large networks, a number of dimensionality reduction techniques for graphs have been developed. However, the extent to which information is lost or preserved when these techniques are employed has not yet been clear. Here we develop a framework, based on algorithmic information theory, to quantify the extent to which informatio

Yuina Kanai, Takeo Mori, Sho Naimen, Kohei Yamagami

We have successfully observed linear dichroism in angle-resolved Yb3+ 3d5/2 core-level photoemission spectra for YbB12 in cubic symmetry. Its anisotropic 4f charge distribution due to the crystal-field splitting is responsible for the linear dichroism, which has been verified by spectral simulations using ionic calculations with the full multiplet theory for

Tiben Che, Jingwei Xu, Gwan Choi

This paper presents a hardware architecture of fast simplified successive cancellation (fast-SSC) algorithm for polar codes, which significantly reduces the decoding latency and dramatically increases the throughput. Algorithmically, fast-SSC algorithm suffers from the fact that its decoder scheduling and the consequent architecture depends on the code rate;

Gilles Rebelles

In this paper, we address the problem of estimating a multidimensional density $f$ by using indirect observations from the statistical model $Y=X+\varepsilon$. Here, $\varepsilon$ is a measurement error independent of the random vector $X$ of interest, and having a known density with respect to the Lebesgue measure. Our aim is to obtain optimal accuracy of e

Altair Santos de Oliveira Sobrinho, Camila Fogaça de Oliveira, Carolina Massae Kita, Érica Regina Takano Natti

This work investigated the stability and asymptotic behavior of some Lotka Volterra type models. We used the Liapunov method which consists in analyzing the stability of systems of ordinary differential equations (ODEs) around the equilibrium when they submitted to perturbations in the initial conditions

Fernando Soler-Toscano, Hector Zenil

Given the widespread use of lossless compression algorithms to approximate algorithmic (Kolmogorov-Chaitin) complexity, and that lossless compression algorithms fall short at characterizing patterns other than statistical ones not different to entropy estimations, here we explore an alternative and complementary approach. We study formal properties of a Levi

Hugo Corrales, Carlos E. Valencia

Given a graph $G=(V, E)$, its generalized Laplacian matrix is given by \[ L(G,X_G)_{u,v}= \begin{cases} x_u&\text{if }u=v,\\ -m_{uv}&\text{if }u\neq v, \end{cases} \] where $X_G=\{x_u\, | \, u\in V(G)\}$ is a set of indeterminates and $m_{uv}$ is the number of edges between $u$ and $v$. The $j$-critical ideal of $G$ is the determinantal ideal generated by th

Xing Shi Cai, Luc Devroye

A deterministic finite automaton (DFA) of $n$ states over a $k$-letter alphabet can be seen as a digraph with $n$ vertices which all have exactly $k$ labeled out-arcs ($k$-out digraph). In 1973 Grusho first proved that with high probability (whp) in a random $k$-out digraph there is a strongly connected component (SCC) of linear size that is reachable from a

Amir Sheikhahmadi, Mohammad A. Nematbakhsh, Arman Shokrollahi

Recently an increasing amount of research is devoted to the question of how the most influential nodes (seeds) can be found effectively in a complex network. There are a number of measures proposed for this purpose, for instance, high-degree centrality measure reflects the importance of the network topology and has a reasonable runtime performance to find a

Jijuan Chen, Tao Wang, Huiqin Zhang

An acyclic edge coloring of a graph $G$ is a proper edge coloring such that every cycle is colored with at least three colors. The acyclic chromatic index $\chiup_{a}&#39;(G)$ of a graph $G$ is the least number of colors in an acyclic edge coloring of $G$. It was conjectured that $\chiup&#39;_{a}(G)\leq Δ(G) + 2$ for any simple graph $G$ with maximum degree

Simone Ugolini

In this paper we present an alternative approach to a problem dealt with by Rosales et al. In particular, once a base $b$ for the representation of the integers is fixed, we describe a procedure for constructing the smallest multiplicative subsemigroup of the positive integers closed with respect to the number of digits which contains a set of positive integ

Jesper Pedersen, Alexandre Graell i Amat, Iryna Andriyanova, Fredrik Brännström

We consider distributed storage (DS) for a wireless network where mobile devices arrive and depart according to a Poisson random process. Content is stored in a number of mobile devices, using an erasure correcting code. When requesting a piece of content, a user retrieves the content from the mobile devices using device-to-device communication or, if not po

Davit R. Petrosyan, George S. Pogosyan

In the present work the classical problem of harmonic oscillator in the hyperbolic space $H_2^2$: $z_0^2+z_1^2-z_2^2-z_3^2=R^2$ has been completely solved in framework of Hamilton-Jacobi equation. We have shown that the harmonic oscillator on $H_2^2$, as in the other spaces with constant curvature, is exactly solvable and belongs to the class of maximally su

J. M. C. Montanus

The horizontal lateral density of a cosmic air shower with a non-zero zenith angle is asymmetric. The asymmetry consist of a stretching of the iso-density contours to ellipses and to a shift of the center of the elliptic contours with respect to the core of the shower. The shift is caused by atmospheric attenuation. The modeling of the attenuation results in

Lukas Greuter, Sebastian Starosielec, Andreas V. Kuhlmann, Richard J. Warburton

We investigate the strong coupling regime of a self-assembled quantum dot in a tunable microcavity with dark-field laser spectroscopy. The high quality of the spectra allows the lineshapes to be analyzed revealing subtle quantum interferences. Agreement with a model calculation is achieved only by including exciton dephasing which reduces the cooperativity f

Michael G. Hansen, Evangelos Magoulakis, Qun-Feng Chen, Ingo Ernsting

We demonstrate a powerful tool for high-resolution mid-IR spectroscopy and frequency metrology with quantum cascade lasers (QCLs). We have implemented frequency stabilization of a QCL to an ultra-low expansion (ULE) reference cavity, via upconversion to the near-IR spectral range, at a level of $1\times10^{-13}$. The absolute frequency of the QCL is measured

E. R. Brandão, C. H. Costa, M. S. Vasconcelos, D. H. A. L. Anselmo

We study theoretically the transmission spectra in one-dimensional photonic quasicrystals, made up of SiO$_2$($A$) and TiO$_2$($B$) materials, organized following the Octonacci sequence, where the $n$th-stage of the multilayer $S_{n}$ is given by the rule $S_{n}=S_{n-1}S_{n-2}S_{n-1}$, for $n\geq 3$ and with $S_{1}=A$ and $S_{2}=B$. The expression for transm

E. Costa, E. Ribeiro

The goal of this article is to establish estimates involving the Yamabe minimal volume, mixed minimal volume and some topological invariants on compact 4-manifolds. In addition, we provide topological sphere theorems for compact submanifolds of spheres and Euclidean spaces, provided that the full norm of the second fundamental form is suitably bounded.

Panki Kim, Takashi Kumagai, Jian Wang

Based on two-sided heat kernel estimates for a class of symmetric jump processes on metric measure spaces, the laws of the iterated logarithm (LILs) for sample paths, local times and ranges are established. In particular, the LILs are obtained for $β$-stable-like processes on $α$-sets with $β>0$.

Bo Lu, Pablo Burset, Keiji Yada, Yukio Tanaka

We investigate the charge transport property of superconductor (S) /normal metal (N) / ferromagnet insulator (FI) /(normal metal) N&#39; and S/N/FI/N&#39;/S Josephson junctions on a three-dimensional topological insulator surface. We find asymmetric local density of states (LDOSs) in a S/N/FI/N&#39; junction and show that the finite length of the N interlaye

Subhash Bose, Firoza Sutaria, Brijesh Kumar, Chetna Duggal

We present optical photometric and spectroscopic observations of supernova 2013ej. It is one of the brightest type II supernovae exploded in a nearby ($\sim 10$ Mpc) galaxy NGC 628. The light curve characteristics are similar to type II SNe, but with a relatively shorter ($ \sim85 $ day) and steeper ($ \sim1.7 $ mag (100 d)$^{-1} $ in V) plateau phase. The S

Qingkun Zhang, Lin Wang, Weimin Li, Weiwei Gao

The upgrade project of Hefei Light Source storage ring is under way. In this paper, the broadband impedances of resistive wall and coated ceramic vacuum chamber were calculated using the analytic formula, the wake fields and impedances of other designed vacuum chambers have been simulated by the CST code, and then the broadband impedances model was obtained.

Gedas Bertasius, Jianbo Shi, Lorenzo Torresani

Most of the current boundary detection systems rely exclusively on low-level features, such as color and texture. However, perception studies suggest that humans employ object-level reasoning when judging if a particular pixel is a boundary. Inspired by this observation, in this work we show how to predict boundaries by exploiting object-level features from

Tran Doan Huan, Vu Ngoc Tuoc, Nguyen Viet Minh

Organic-inorganic hybrid halide perovskites, in which the A cations of an ABX$_3$ perovskite are replaced by organic cations, may be used for photovoltaic and solar thermoelectric applications. In this contribution, we systematically study three lead-free hybrid perovskites, i.e., methylammonium tin iodide CH$_3$NH$_3$SnI$_3$, ammonium tin iodide NH$_4$SnI$_

Alexander V. Devyatkin, Ekaterina A. Bashakova, Viacheslav Yu. Slesarenko

The space probe &#39;New Horizon&#39; was launched on 19th of January 2006 in order to study Pluto and its moons. Spacecraft will fly by Pluto as close as 12500 km in the middle of July 2015 and will get the most detailed images of Pluto and its moon until this moment. At the same time, observation obtained by the ground-based telescopes may also be helpful

Hui Xu, Jean-Eloi W. Lombard, Spencer J. Sherwin

We consider a smooth forward facing step defined by the Gauss error function of height 4-30\% and four times the width of the local boundary layer thickness $δ_{99}$. The boundary layer flow over a smooth forward-facing stepped plate is studied with particular emphasis on stabilisation and destabilisation of the Tollmien-Schlichting (TS) waves and subsequent

Yann Magnin, Alexandre Zappelli, Hakim Amara, François Ducastelle

The carbon rich phase diagrams of nickel-carbon nanoparticles, relevant to catalysis and catalytic chemical vapor deposition synthesis of carbon nanotubes, are calculated for system sizes up to about 3 nanometers (807 Ni atoms). A tight binding model for interatomic interactions drives the Grand Canonical Monte Carlo simulations used to locate solid, core/sh

Keith B. Wiley, Randal A. Koene

Mind uploading speculation and debate often concludes that a procedure described as gradual in-place replacement preserves personal identity while a procedure described as destructive scan-and-copy produces some other identity in the target substrate such that personal identity is lost along with the biological brain. This paper demonstrates a chain of reaso

Chichuan Jin, Chris Done, Martin Ward

RX J1140.1+0307 (hereafter RX1140) is a Narrow Line Seyfert 1 (NLS1) with one of the lowest black hole masses known in an AGN (M ${\le} 10^6$ M$_{\odot}$). We show results from two new {\it XMM-Newton} observations, showing soft 2-10~keV spectra, a strong excess at lower energies, and fast X-ray variability as is typical of this class. The soft excess can be

S. L. Cherkas, V. L. Kalashnikov

It is shown that the initial conditions in the quasi-Heisenberg quantization scheme can be set at the initial cosmological singularity per se. This possibility is provided by finiteness of some quantities, namely momentums of the dynamical variables, at a singularity, in spite of infinity of the dynamical variables themselves. The uncertainty principle allow

Martin Lück, Arne Meier

We classify the complexity of the LTL satisfiability and model checking problems for several standard parameterisations. The investigated parameters are temporal depth, number of propositional variables and formula treewidth, resp., pathwidth. We show that all operator fragments of LTL under the investigated parameterisations are intractable in the sense of

Theodoros Moysiadis, Konstantinos Fokianos

We introduce the concept of local dyadic stationarity, to account for non-stationary time series, within the framework of Walsh-Fourier analysis. We define and study the time varying dyadic ARMA models (tvDARMA). It is proven that the general tvDARMA process can be approximated locally by either a tvDMA and a tvDAR process.

J. -B Bardet, A Christen, J Fontbona

We establish explicit exponential convergence estimates for the renewal theorem, in terms of a uniform component of the inter arrival distribution, of its Laplace transform which is assumed finite on a positive interval, and of the Laplace transform of some related random variable. Our proof is based on a coupling construction relying on discrete-time Markov

Fyodor Gainullin

In this paper we investigate the question of when different surgeries on a knot can produce identical manifolds. We show that given a knot in a homology sphere, unless the knot is quite special, there is a bound on the number of slopes that can produce a fixed manifold that depends only on this fixed manifold and the homology sphere the knot is in. By findin

Tomas Husek, Karol Kampf, Jiri Novotny

We have recalculated the Mikaelian and Smith radiative corrections to the Dalitz decay $π^0\to e^+e^-γ$ beyond the soft-photon approximation, i.e. over the whole range of the Dalitz plot and with no restrictions on the radiative photon. In contrast to the previous calculations, we did not neglect the terms of order higher than $\mathcal{O}(m^2)$ and also inc

Benny Sudakov, Jan Volec

Let G be an n-vertex graph that contains linearly many cherries (i.e., paths on 3 vertices), and let c be a coloring of the edges of the complete graph K_n such that at each vertex every color appears only constantly many times. In 1979, Shearer conjectured that such a coloring c must contain a properly colored copy of G. We establish this conjecture in a st

Juho Kokkala, Arno Solin, Simo Särkkä

We consider approximate maximum likelihood parameter estimation in nonlinear state-space models. We discuss both direct optimization of the likelihood and expectation--maximization (EM). For EM, we also give closed-form expressions for the maximization step in a class of models that are linear in parameters and have additive noise. To obtain approximations t

Laurent Jacques

Under which conditions and with which distortions can we preserve the pairwise-distances of low-complexity vectors, e.g., for structured sets such as the set of sparse vectors or the one of low-rank matrices, when these are mapped in a finite set of vectors? This work addresses this general question through the specific use of a quantized and dithered random

Filippo Callegaro, Emanuele Delucchi

We compute the cohomology ring of the complement of a toric arrangement with integer coefficients and investigate its dependency from the arrangement&#39;s combinatorial data. To this end, we study a morphism of spectral sequences associated to certain combinatorially defined subcomplexes of the toric Salvetti category in the complexified case, and use a tec

C. P. Martin, David G. Navarro

We deduce an evolution equation for an arbitrary hybrid Seiberg-Witten map for compact gauge groups by using the antifield formalism. We show how this evolution equation can be used to obtain the hybrid Seiberg-Witten map as an expansion, which is $θ$-exact, in the number of ordinary fields. We compute explicitly this expansion up to order three in the numbe

Michael Schönlein, Uwe Helmke

We investigate the task of controlling ensembles of initial and terminal state vectors of parameter-dependent linear systems by applying parameter-independent open loop controls. Necessary, as well as sufficient, conditions for ensemble controllability are established, using tools from complex approximation theory. For real analytic families of linear system

Shun Uchino, Akiyuki Tokuno

We consider a two-leg Bose-Hubbard ladder in the presence of a magnetic flux. We make use of Gross-Pitaevskii, Bogoliubov, bosonization, and renormalization group approaches to reveal a structure of ground-state phase diagrams in a weak-coupling regime relevant to cold atom experiments. It is found that except for a certain flux $ϕ=π$, the system shows diffe

Raphaël Beuzart-Plessis

Let $G$ be a reductive $p$-adic group. We give a short proof of the fact that $G$ always admits supercuspidal complex representations. This result has already been established by A. Kret using the Deligne-Lusztig theory of representations of finite groups of Lie type. Our argument is of a different nature and is self-contained. It is based on the Harish-Chan

Joanna Pietraszewicz, Piotr Deuar

We determine the regime where the widespread classical field description for quantum Bose gases is quantitatively accurate in 1d, 2d, and 3d by a careful study of the ideal gas limit. Numerical benchmarking in 1d shows that the ideal gas results carry over unchanged into the weakly interacting gas. The optimum high energy cutoff is in general shown to depend

O. Patsahan

Gas-liquid criticality in the ultrasoft restricted primitive model (URPM) of polyelectrolytes is studied using the collective variables-based theory. For the model, an effective Hamiltonian is derived and explicit expressions for all the coefficients are found in a one-loop approximation. Based on this Hamiltonian, the phase and critical behaviour is analyse

Masahito Hayashi, Hiroyasu Tajima

There exist two formulations for quantum heat engine that models an energy transfer between two microscopic systems. One is semi-classical scenario, and the other is full quantum scenario. The former is formulated as a unitary evolution for the internal system, and is adopted by the community of statistical mechanics. In the latter, the whole process is form

Pierre Henry-Labordère, Christian Litterer, Zhenjie Ren

We derive an algorithm in the spirit of Rogers and Davis & Burstein that leads to upper bounds for stochastic control problems. Our bounds complement lower biased estimates recently obtained in the work of Guyon & Henry-Labordère. We evaluate our estimates in numerical examples motivated from mathematical finance.

A. Ali, Z. Raza, A. A. Bhatti

This work is devoted to establish a general expression for calculating the bond incident degree (BID) indices of polyomino chains and to characterize the extremal polyomino chains with respect to several well known BID indices. From the derived results, all the results of [M. An, L. Xiong, Extremal polyomino chains with respect to general Randić index, \text

Daomin Cao, Shuanglong Li, Peng Luo

We are concerned with the following nonlinear Schrödinger equation $$-\varepsilon^2Δu+ V(x)u=|u|^{p-2}u,~u\in H^1(\R^N),$$ where $N\geq 3$, $2<p<\frac{2N}{N-2}$. For $\varepsilon$ small enough and a class of $V(x)$, we show the uniqueness of positive multi-bump solutions concentrating at $k$ different critical points of $V(x)$ under certain assumptions on as

Toby Cubitt, Michael Kastoryano, Ashley Montanaro, Kristan Temme

We develop reverse versions of hypercontractive inequalities for quantum channels. By generalizing classical techniques, we prove a reverse hypercontractive inequality for tensor products of qubit depolarizing channels. We apply this to obtain a rapid mixing result for depolarizing noise applied to large subspaces, and to prove bounds on a quantum generaliza

Andras Suto

The total momentum of $N$ interacting bosons or fermions in a cube equipped with periodic boundary conditions is a conserved quantity. Its eigenvalues follow a probability distribution, determined by the thermal equilibrium state. While in non-interacting systems the distribution is normal with variance $\sim N$, interaction couples the single-particle momen

E Chermak, Peter Reinhardt, Bastien Mussard, Janos Angyan

Selecting excitations in localized orbitals to calculate long-range correlation contributions to range-separated density-functional theory can reduce the overall computational effort significantly. Beyond simple selection schemes of excited determinants, the dispersion-only approximation, which avoids counterpoise-corrected monomer calculations, is shown to

Ziv Goldfeld, Gerhard Kramer, Haim H. Permuter

The broadcast channel (BC) with one common and two private messages with leakage constraints is studied, where leakage rate refers to the normalized mutual information between a message and a channel symbol string. Each private message is destined for a different user and the leakage rate to the other receiver must satisfy a constraint. This model captures s

Miika Hannula, Juha Kontinen, Jonni Virtema, Heribert Vollmer

We classify the computational complexity of the satisfiability, validity and model-checking problems for propositional independence, inclusion, and team logic. Our main result shows that the satisfiability and validity problems for propositional team logic are complete for alternating exponential-time with polynomially many alternations.

Richard G. Forbes, Jonathan H. B. Deane, Andreas Fischer, Marwan S. Mousa

The commonest method of characterizing a cold field electron emitter is to measure its current-voltage characteristics, and the commonest method of analysing these characteristics is by means of a Fowler-Nordheim (FN) plot. This tutorial/review-type paper outlines a more systematic method of setting out the Fowler-Nordheim-type theory of cold field electron

Bruno Durand, Andrei Romashchenko

We study tilings of the plane that combine strong properties of different nature: combinatorial and algorithmic. We prove existence of a tile set that accepts only quasiperiodic and non-recursive tilings. Our construction is based on the fixed point construction; we improve this general technique and make it enforce the property of local regularity of tiling

E. E. O. Ishida, S. D. P. Vitenti, M. Penna-Lima, J. Cisewski

Approximate Bayesian Computation (ABC) enables parameter inference for complex physical systems in cases where the true likelihood function is unknown, unavailable, or computationally too expensive. It relies on the forward simulation of mock data and comparison between observed and synthetic catalogues. Here we present cosmoabc, a Python ABC sampler featuri

Eduardo Mascarenhas, Hugo Flayac, Vincenzo Savona

We develop a numerical procedure to efficiently model the nonequilibrium steady state of one-dimensional arrays of open quantum systems, based on a matrix-product operator ansatz for the density matrix. The procedure searches for the null eigenvalue of the Liouvillian superoperator by sweeping along the system while carrying out a partial diagonalization of

Leo N. Geppert, Katja Ickstadt, Alexander Munteanu, Jens Quedenfeld

This article deals with random projections applied as a data reduction technique for Bayesian regression analysis. We show sufficient conditions under which the entire $d$-dimensional distribution is approximately preserved under random projections by reducing the number of data points from $n$ to $k\in O(\operatorname{poly}(d/\varepsilon))$ in the case $n\g

MAGIC Collaboration, J. Aleksić, S. Ansoldi, L. A. Antonelli

The high-frequency-peaked BL Lac (HBL) 1ES 0806+524 (z = 0.138) was discovered in VHE $γ$ rays in 2008. Until now, the broad-band spectrum of 1ES 0806+524 has been only poorly characterized, in particular at high energies. We analysed multiwavelength observations from $γ$ rays to radio performed from 2011 January to March, which were triggered by the high ac

Christian Bonatti, Bruno Santiago

In $64$ E. Lima proved that commuting vector fields on surfaces with non-zero Euler characteristic have common zeros. Such statement is empty in dimension $3$, since all the Euler characteristics vanish. Nevertheless, \cite{Bonatti_analiticos} proposed a local version, replacing the Euler characteristic by the Poincaré-Hopf index of a vector field $X$ in a r

Tomas Vojir, Jiri Matas, Jana Noskova

In this paper, we propose a novel method for visual object tracking called HMMTxD. The method fuses observations from complementary out-of-the box trackers and a detector by utilizing a hidden Markov model whose latent states correspond to a binary vector expressing the failure of individual trackers. The Markov model is trained in an unsupervised way, relyi

Cristina Costoya, Jérôme Scherer, Antonio Viruel

Nilpotency for discrete groups can be defined in terms of central extensions. In this paper, the analogous definition for spaces is stated in terms of principal fibrations having infinite loop spaces as fibers, yielding a new invariant we compare with classical cocategory, but also with the more recent notion of homotopy nilpotency introduced by Biedermann a

A. K. Bhuniya, S. Bera

Let $ G $ be a finite group of order $ n$. The strong power graph $\mathcal{P}_s(G) $ of $G$ is the undirected graph whose vertices are the elements of $G$ such that two distinct vertices $a$ and $b$ are adjacent if $a^{{m}_1}$=$b^{{m}_2}$ for some positive integers ${m}_1 ,{m}_2 < n$. In this article we classify all groups $G$ for which $\mathcal{P}_s(G)$ i

Miryana Grigorova, Peter Imkeller, Elias Offen, Youssef Ouknine

In the first part of the paper, we study reflected backward stochastic differential equations (RBSDEs) with lower obstacle which is assumed to be right upper-semicontinuous but not necessarily right-continuous. We prove existence and uniqueness of the solutions to such RBSDEs in appropriate Banach spaces. The result is established by using some tools from th

Luigi Vigneri, Jaideep Chandrashekar, Ioannis Pefkianakis, Olivier Heen

There are over 1.2 million applications on the Google Play store today with a large number of competing applications for any given use or function. This creates challenges for users in selecting the right application. Moreover, some of the applications being of dubious origin, there are no mechanisms for users to understand who the applications are talking t

Kirsten Vincke, Andreas Breslau, Susanne Pfalzner

Context. Most stars are born in clusters, thus the protoplanetary discs surrounding the newly formed stars might be influenced by this environment. Isolated star-disc encounters have previously been studied, and it was shown that very close encounters are necessary to completely destroy discs. However, relatively distant encounters are still able to change t

G. F. Gribakin, A. R. Swann

A model for positron binding to polar molecules is considered by combining the dipole potential outside the molecule with a strongly repulsive core of a given radius. Using existing experimental data on binding energies leads to unphysically small core radii for all of the molecules studied. This suggests that electron-positron correlations neglected in the

Hajime Fukuda, Keisuke Harigaya, Masahiro Ibe, Tsutomu T. Yanagida

We pursue a class of visible axion models where the axion mass is enhanced by strong dynamics in a mirrored copy of the Standard Model in the line of the idea put forward by Rubakov. In particular, we examine the consistency of the models with laboratory, astrophysical, and cosmological constraints. As a result, viable parameter regions are found, where the

Yen-Chun Tseng, David M. -T. Kuo, Yia-Chung Chang, Chia-Wei Tsai

The thermoelectric properties of quantum dot arrays (QDAs) embedded in nanowires connected to electrodes are studied theoretically in the Coulomb blockade regime. A Hurbbard-Anderson model is used to simulate the electronic contribution to thermoelectric proper- ties of a QDA junction system. The electrical conductance, Seebeck coefficient, and electron ther

Judit Romhányi, Guido Burkard, András Pályi

We theoretically study coherent subharmonic (multi-photon) transitions of a harmonically driven spin. We consider two cases: magnetic resonance (MR) with a misaligned, i.e., non-transversal driving field, and electrically driven spin resonance (EDSR) of an electron confined in a one-dimensional, parabolic quantum dot, subject to Rashba spin-orbit interaction

Samuel Rosa, Radoslav Harman

Suppose that we intend to perform an experiment consisting of a set of independent trials. The mean value of the response of each trial is assumed to be equal to the sum of the effect of the treatment selected for the trial, and some nuisance effects, e.g., the effect of a time trend, or blocking. In this model, we examine optimal approximate designs for the

B. Grzadkowski, O. M. Ogreid, P. Osland

We review CP properties of the Two-Higgs-Doublet model. In particular, we show that spontaneous CP violation occurs in the parameter space on the border between regions allowing explicit CP violation and those where there is another minimum, deeper than the one corresponding to v=246 GeV. We discuss weak-basis invariants which describe CP violation and expre

Ran Shi, Jian Kang

Motivated by the needs of selecting important features for massive neuroimaging data, we propose a spatially varying coefficient model (SVCMs) with sparsity and piecewise smoothness imposed on the coefficient functions. A new class of nonparametric priors is developed based on thresholded multiresolution Gaussian processes (TMGP). We show that the TMGP has a

Sandrine Codis, Christophe Pichon, Dmitry Pogosyan

The geometry of the cosmic web drives in part the spin acquisition of galaxies. This can be explained in a Lagrangian framework, by identifying the specific long-wavelength correlations within the primordial Gaussian random field which are relevant to spin acquisition. Tidal Torque Theory is revisited in the context of such anisotropic environments, biased b

Dong Quan Ngoc Nguyen

In 1938, Skolem conjectured that $\mathbf{SL}_n(\mathbb{Z})$ is not a polynomial family for any $n \ge 2$. Carter and Keller disproved Skolem&#39;s conjecture for all $n \ge 3$ by proving that $\mathbf{SL}_n(\mathbb{Z})$ is boundedly generated by the elementary matrices, and hence a polynomial family for any $n \ge 3$. Only recently, Vaserstein refuted Skole

Sabine Hossenfelder

I explain why there are no Poincaré-invariant networks with a locally finite distribution of nodes and links in Minkowski-spacetime of any dimension.