March 2010 arXiv papers — page 49
Showing 4,801–4,900 of 5,984 papers
Xin-She Yang
Modern optimisation algorithms are often metaheuristic, and they are very promising in solving NP-hard optimization problems. In this paper, we show how to use the recently developed Firefly Algorithm to solve nonlinear design problems. For the standard pressure vessel design optimisation, the optimal solution found by FA is far better than the best solution
Mika Prunnila, Johanna Meltaus
The authors describe how acoustic phonons can directly tunnel through vacuum and, therefore, transmit energy and conduct heat between bodies that are separated by a vacuum gap. This effect is enabled by introducing a coupling mechanism, such as piezoelectricity, that strongly couples electric field and lattice deformation. The electric field leaks into the v
Radiative hydrodynamics simulations of red supergiant stars: II. simulations of convection on Betelgeuse match interferometric observations
astro-ph.SRA. Chiavassa, X. Haubois, J. S. Young, B. Plez
Context. The red supergiant (RSG) Betelgeuse is an irregular variable star. Convection may play an important role in understanding this variability. Interferometric observations can be interpreted using sophisticated simulations of stellar convection. Aims. We compare the visibility curves and closure phases obtained from our 3D simulation of RSG convection
Canonical frames for distributions of odd rank and corank 2 with maximal first Kronecker index
math.DGWojciech Krynski, Igor Zelenko
We construct canonical frames and find all maximally symmetric models for a natural generic class of corank 2 distributions on manifolds of odd dimension greater or equal to 7. This class of distributions is characterized by the following two conditions: the pencil of 2-forms associated with the corresponding Pfaffian system has the maximal possible first Kr
Denis Sych, Gerd Leuchs
In the classical world one can construct two identical systems which have identical behavior and give identical measurement results. We show this to be impossible in the quantum domain. We prove that after the same quantum measurement two different quantum systems cannot yield always identical results, provided the possible measurement results belong to a no
Branislav Sobota, Milan Guzan
This paper describes visualization of chaotic attractor and elements of the singularities in 3D space. 3D view of these effects enables to create a demonstrative projection about relations of chaos generated by physical circuit, the Chua's circuit. Via macro views on chaotic attractor is obtained not only visual space illustration of representative point
Lifetime of the embedded phase of low-mass star formation and the envelope depletion rates
astro-ph.SREduard Vorobyov
Motivated by a considerable scatter in the observationally inferred lifetimes of the embedded phase of star formation, we study the duration of the Class 0 and Class I phases in upper-mass brown dwarfs and low-mass stars using numerical hydrodynamics simulations of the gravitational collapse of a large sample of cloud cores. We resolve the formation of a sta
Automatic derivation of domain terms and concept location based on the analysis of the identifiers
cs.CLPeter Vaclavik, Jaroslav Poruban, Marek Mezei
Developers express the meaning of the domain ideas in specifically selected identifiers and comments that form the target implemented code. Software maintenance requires knowledge and understanding of the encoded ideas. This paper presents a way how to create automatically domain vocabulary. Knowledge of domain vocabulary supports the comprehension of a spec
From Graphene to Bismuth Telluride: Mechanical Exfoliation of Quasi-2D Crystals for Applications in Thermoelectrics and Topological Insulators
cond-mat.mes-hallDesalegne Teweldebrhan, Vivek Goyal, Alexander A. Balandin
Bismuth telluride (Bi2Te3) and its alloys are the best bulk thermoelectric materials known today. The stacked quasi-two-dimensional (2D) layers of Bi2Te3 were also identified as topological insulators. In this paper we describe a method for graphene-inspired exfoliation of crystalline bismuth telluride films with a thickness of a few atoms. The atomically th
Stefan Korecko, Branislav Sobota
This paper deals with the parallel raytracing part of virtual-reality system PROLAND, developed at the home institution of authors. It describes an actual implementation of the raytracing part and introduces a Coloured Petri Nets model of the implementation. The model is used for an evaluation of the implementation by means of simulation-based performance an
Second Comment on "Contextuality within quantum mechanics manifested in subensemble mean values" [Phys. Lett. A 373 (2009) 3430]
quant-phF. De Zela
I examine Pan and Home's reply to my Comment on their proposal for testing noncontextual models. I show that the Kochen-Specker model for a qubit does explain all outcomes of a test based on such a proposal, so that it would be inconclusive about the untenability of realistic, noncontextual models.
RENO: An Experiment for Neutrino Oscillation Parameter theta_13 Using Reactor Neutrinos at Yonggwang
hep-exRENO Collaboration, J. K. Ahn
The RENO experiment is a short baseline neutrino experiment in Korea aiming to measure the neutrino mixing angle theta_13 or set limit to sin^2(2 theta_13) less than 0.02. This document describes physics goals, experimental site, detector design, scintillator, electronics, calibration, simulation, and physics reach.
Reduction of high reset currents in unipolar resistance switching Pt/SrTiOx/Pt capacitors using acceptor doping
cond-mat.mtrl-sciS. B. Lee, A. Kim, J. S. Lee, S. H. Chang
The high reset current, IR, in unipolar resistance switching is an important issue which should be resolved for practical applications in nonvolatile memories. We showed that,during the forming and set processes, the compliance current, Icomp, can work as a crucial parameter to reduce IR. Doping with Co or Mn can significantly reduce the leakage current in c
Gyöngyvér Márton
Up to now, for efficiency reasons cryptographic algorithm has been written in an imperative language. But to get acquaintance with a functional programming language a question arises: functional programming offers some new for secure communication or not? This article investigates this question giving an overview on some cryptography algorithms and presents
Chris Van Den Broeck
Einstein Telescope (ET) is a possible third generation ground-based gravitational wave observatory for which a design study is currently being carried out. A brief (and non-exhaustive) overview is given of ET's projected capabilities regarding astrophysics and cosmology through observations of inspiraling and coalescing compact binaries. In particular, E
Antal Bege, Zoltán Kása
A coding method using binary sequences is presented for different computation problems related to Catalan numbers. This method proves in a very easy way the equivalence of these problems.
Temitope Gbolahan Jaiyeola
The pair $(G_H,\cdot)$ is called a special loop if $(G,\cdot)$ is a loop with an arbitrary subloop $(H,\cdot)$. A special loop $(G_H,\cdot)$ is called a second Smarandache Bol loop(S$_{2^{\tiny\textrm{nd}}}$BL) if and only if it obeys the second Smarandache Bol identity $(xs\cdot z)s=x(sz\cdot s)$ for all $x,z$ in $G$ and $s$ in $H$. The popularly known and
Sumit Kumar Rai, Bhabani Prasad Mandal
We derive the various forms of BRST symmetry using Batalin-Fradkin-Vilkovisky approach in the case of Abelian 2-form gauge theory. We show that the so-called dual BRST symmetry is not an independent symmetry but the generalization of BRST symmetry obtained from the canonical transformation in the bosonic and ghost sector. We further obtain the new forms of b
Temitope Gbolahan Jaiyeola, John Olushola Adeniran
Michael Kinyon's 2005 open problem, based on the universality of Osborn loops is solved. It is shown that not every Osborn loop is universal.
R. Ishikawa, S. Tsuneta, J. Jurcak
We infer the 3D magnetic structure of a transient horizontal magnetic field (THMF) during its evolution through the photosphere using SIRGAUS inversion code. The SIRGAUS code is a modified version of SIR (Stokes Inversion based on Response function), and allows for retrieval of information on the magnetic and thermodynamic parameters of the flux tube embedde
M. Agundez, J. R. Goicoechea, J. Cernicharo, A. Faure
The internal energy available in vibrationally excited H2 molecules can be used to overcome or diminish the activation barrier of various chemical reactions of interest for molecular astrophysics. In this article we investigate in detail the impact on the chemical composition of interstellar clouds of the reactions of vibrationally excited H2 with C+, He+, O
Nicolas Clément, Stéphane Pleutin, Oliver Seitz, Stéphane Lenfant
We report low frequency tunnel current noise characteristics of an organic monolayer tunnel junction. The measured devices, n-Si/alkyl chain (C18H37)/Al junctions, exhibit a clear 1/ f^y power spectrum noise with 1< y <1.2. We observe a slight bias dependent background of the normalized current noise power spectrum (SI/I^2). However, a local increase is also
Alexei Rudakov
In this paper we define the degree of a morphism between (generalized) Verma modules over a graded Lie superalgebra and construct series of morphisms of various degrees between (generalized) Verma modules over the exceptional infinite-dimensional linearly compact simple Lie superalgebra E(5,10). We prove that all such morphisms of degree 1 are found.
Jianpo Guo, Fenghui Zhang, Xuefei Chen, Zhanwen Han
With more and more exoplanets being detected, it is paid closer attention to whether there are lives outside solar system. We try to obtain habitable zones and the probability distribution of terrestrial planets in habitable zones around host stars. Using Eggleton's code, we calculate the evolution of stars with masses less than 4.00 \mo. We also use the
Long Dang, Massimo Boninsegni
We study by Quantum Monte Carlo simulations the phase diagram of lattice hard core bosons with nearest-neighbour repulsive interactions, in the presence of a super-lattice of adsorption sites. For a moderate adsorption strength, the system forms crystal phases registered with the adsorption lattice; a "supersolid" phase exists, on both the vacancy an
Huei-Ru Chen, Sheng-Yuan Liu, Yu-Nung Su, Qizhou Zhang
We have observed the J=3-2 transition of N2H+ and N2D+ to investigate the trend of deuterium fractionation with evolutionary stage in three selected regions in the Infrared Dark Cloud (IRDC) G28.34+0.06 with the Submillimeter Telescope (SMT) and the Submillimeter Array (SMA). A comprehensible enhancement of roughly 3 orders of magnitude in deuterium fraction
Javad Ghaderi, R. Srikant
Recently, it has been shown that CSMA algorithms which use queue length-based link weights can achieve throughput optimality in wireless networks. In particular, a key result by Rajagopalan, Shah, and Shin (2009) shows that, if the link weights are chosen to be of the form log(log(q)) (where q is the queue-length), then throughput optimality is achieved. In
Ll. Bel
A time-dependent model of space-time is used to suggest simple explanations for the increasing of the Astronomical unit, as well as the increasing of the distance from the Earth to the Moon. The Pioneer anomaly is also considered.
On the Solution to the "Frozen Star" Paradox, Nature of Astrophysical Black Holes, non-Existence of Gravitational Singularity in the Physical Universe and Applicability of the Birkhoff's Theorem
gr-qcShuang-Nan Zhang
Oppenheimer and Snyder found in 1939 that gravitational collapse in vacuum produces a "frozen star", i.e., the collapsing matter only asymptotically approaches the gravitational radius (event horizon) of the mass, but never crosses it within a finite time for an external observer. Based upon our recent publication on the problem of gravitational coll
J. Wang, J. S. Deng, J. Y. Wei
The normalized radial distribution of young stellar populations (and cold gas) in nearby galactic disks is compared between AGN host galaxies and starforming galaxies (both with Hubble types between S0/a and Scd) by using type II supernovae (SNe) as tracers. A subset of 140 SNe\,II with available supernova position measurements are selected from the SAI-SDSS
Continuous variable entanglement enhancement and manipulation by a sub-threshold type-II optical parametric amplifier
quant-phYana Shang, Xiaojun Jia, Yumei Shen, Changde Xie
We experimentally demonstrate that the quantum entanglement between amplitude and phase quadratures of optical modes produced from a non-degenerate optical parametric amplifier (NOPA) can be enhanced and manipulated phase-sensitively by means of another NOPA. When both NOPAs operate at de-amplification, the entanglement degree is increased at the cavity reso
Yongying Jiang, Ning Wang, Zhuxia Li, Werner Scheid
The dynamical nucleus-nucleus potentials for fusion reactions 40Ca+40Ca, 48Ca+208Pb and 126Sn+130Te are studied with the improved quantum molecular dynamics (ImQMD) model together with the extended Thomas-Fermi approximation for the kinetic energies of nuclei. The obtained fusion barrier for 40Ca+40Ca is in good agreement with the extracted fusion barrier fr
Chin-Fei Lee, Tatsuhiko I. Hasegawa, Naomi Hirano, Aina Palau
HH 211 is a highly collimated jet originating from a nearby young Class 0 protostar. Here is a follow-up study of the jet with our previous observations at unprecedented resolution up to ~ 0.3" in SiO (J=8-7), CO (J=3-2), and SO (N_J=8_9-7_8). SiO, CO, and SO can all be a good tracer of the HH 211 jet, tracing the internal shocks in the jet. Although the
Xinhua Zhang, Ankan Saha, S. V. N. Vishwanathan
Structured output prediction is an important machine learning problem both in theory and practice, and the max-margin Markov network (\mcn) is an effective approach. All state-of-the-art algorithms for optimizing \mcn\ objectives take at least $O(1/ε)$ number of iterations to find an $ε$ accurate solution. Recent results in structured optimization suggest th
Azzouz Zinoun
Algebraic relations that characterize quantum statistics (Bose-Einstein statistic, Fermi-Dirac statistic, supersymmetry, parastatistic, anyonic statistic, ...) are reformulated herein in terms of a new algebraic structure, which we call para-algebra.
Non-universal tunneling resistance at the quantum critical point of mesoscopic SQUIDs array
cond-mat.mes-hallSujit Sarkar
We calculate the tunnelling resistance at the quantum critical point of a mesoscopic SQUIDs array in the presence of magnetic flux. We find the analytical relation between the magnetic flux induced dissipation strength and the Luttinger liquid parameter of the system. While the experimental finding for the system is around 40-50 mK, we find the behavior of t
The minimal sequence of Reidemister moves bringing the diagram of $(n+1,n)$-torus knot to that of $(n,n+1)$-torus knot
math.GTChuichiro Hayashi, Miwa Hayashi
Let $D(p,q)$ be the usual knot diagram of the $(p,q)$-torus knot, that is, $D(p,q)$ is the closure of the $p$-braid $(σ_1^{-1} σ_2^{-1}... σ_{p-1}^{-1})^q$. As is well-known, $D(p,q)$ and $D(q,p)$ represent the same knot. It is shown that $D(n+1,n)$ can be deformed to $D(n,n+1)$ by a sequence of $\{(n-1)n(2n-1)/6 \} + 1$ Reidemeister moves, which consists of
Simeon Warner
Bibliometric and usage-based analyses and tools highlight the value of information about scholarship contained within the network of authors, articles and usage data. Less progress has been made on populating and using the author side of this network than the article side, in part because of the difficulty of unambiguously identifying authors. I briefly revi
David H. Wolpert, Gregory Benford
In Newcomb's paradox you choose to receive either the contents of a particular closed box, or the contents of both that closed box and another one. Before you choose, a prediction algorithm deduces your choice, and fills the two boxes based on that deduction. Newcomb's paradox is that game theory appears to provide two conflicting recommendations for
A. A. Penin
We argue that the vacuum polarization by the virtual electron-positron pairs can be measured by studying a Josephson junction in a strong magnetic field. The vacuum polarization results in a weak dependence of the Josephson constant on the magnetic field strength which is within the reach of the existing experimental techniques.
M. Boquien, G. Bendo, D. Calzetti, D. Dale
The total infrared (TIR) luminosity from galaxies can be used to examine both star formation and dust physics. We provide here new relations to estimate the TIR luminosity from various Spitzer bands, in particular from the 8 micron and 24 micron bands. To do so, we use 45" subregions within a subsample of nearby face-on spiral galaxies from the Spitzer I
Darryl D. Holm, Rossen I. Ivanov
The relations between smooth and peaked soliton solutions are reviewed for the Camassa-Holm (CH) shallow water wave equation in one spatial dimension. The canonical Hamiltonian formulation of the CH equation in action-angle variables is expressed for solitons by using the scattering data for its associated isospectral eigenvalue problem, rephrased as a Riema
Cristian Armendariz-Picon, Noela Farina Sierra, Jaume Garriga
We study the primordial perturbations generated during a stage of single-field inflation in Einstein-aether theories. Quantum fluctuations of the inflaton and aether fields seed long wavelength adiabatic and isocurvature scalar perturbations, as well as transverse vector perturbations. Geometrically, the isocurvature mode is the potential for the velocity fi
Using Radio Halos and Minihalos to Measure the Distributions of Magnetic Fields and Cosmic-Rays in Galaxy Clusters
astro-ph.COUri Keshet, Abraham Loeb
Some galaxy clusters show diffuse radio emission in the form of giant halos (GHs) on Mpc scales or minihalos (MHs) on smaller scales. Comparing VLA and XMM radial profiles of several such clusters, we find a universal linear correlation between radio and X-ray surface brightness, valid in both types of halos. It implies a halo central emissivity nu*j_nu=10^{
Peter Fornai, Antal Ivanyi
Virtual memory of computers is usually implemented by demand paging. For some page replacement algorithms the number of page faults may increase as the number of page frames increases. Belady, Nelson and Shedler constructed reference strings for which page replacement algorithm FIFO produces near twice more page faults in a larger memory than in a smaller on
Jacob Trier Frederiksen, Troels Haugboelle, Mikhail V. Medvedev, Aake Nordlund
Radiation from many astrophysical sources, e.g. gamma-ray bursts and active galactic nuclei, is believed to arise from relativistically shocked collisionless plasmas. Such sources often exhibit highly transient spectra evolving rapidly, compared with source lifetimes. Radiation emitted from these sources is typically associated with non-linear plasma physics
Benoit Vicedo
The classical integrable structure of Z_4-graded supercoset sigma-models, arising in the AdS/CFT correspondence, is formulated within the R-matrix approach. The central object in this construction is the standard R-matrix of the Z_4-twisted loop algebra. However, in order to correctly describe the Lax matrix within this formalism, the standard inner product
Martin Ammon, Johanna Erdmenger, Matthias Kaminski, Andy O'Bannon
We use gauge-gravity duality to compute spectral functions of fermionic operators in a strongly-coupled defect field theory in p-wave superfluid states. The field theory is (3+1)-dimensional N=4 supersymmetric SU(Nc) Yang-Mills theory, in the 't Hooft limit and with large coupling, coupled to two massless flavors of (2+1)-dimensional N=4 supersymmetric m
Quantum incompressibility of a falling Rydberg atom, and a gravitationally-induced charge separation effect in superconducting systems
quant-phRaymond Y. Chiao
Freely falling point-like objects converge towards the center of the Earth. Hence the gravitational field of the Earth is inhomogeneous, and possesses a tidal component. The free fall of an extended quantum object such as a hydrogen atom prepared in a high principal-quantum-number stretch state, i.e., a circular Rydberg atom, is predicted to fall more slowly
Eric D'Hoker, Per Kraus
Using high-precision numerical analysis, we show that 3+1 dimensional gauge theories holographically dual to 4+1 dimensional Einstein-Maxwell-Chern-Simons theory undergo a quantum phase transition in the presence of a finite charge density and magnetic field. The quantum critical theory has dynamical scaling exponent z=3, and is reached by tuning a relevant
Shariefuddin Pirzada, Guofei Zhou
We give a new and short proof of a theorem on k-hypertournament losing scores due to Zhou et al. [G. Zhou, T. Yao, K. Zhang, On score sequences of k-tournaments, European J. Comb., 21, 8 (2000) 993-1000.]
V. Kotimaki, E. Rasanen
The Aharonov-Bohm effect is investigated in two-dimensional, single-terminal quantum rings in magnetic fields by using time-dependent density-functional theory. We find multiple transport loops leading to the oscillation periods of h/(en), where n is the number of loops. We show that the Aharonov-Bohm oscillations are relatively weakly affected by the electr
F. Finelli, G. Marozzi, A. A. Starobinsky, G. P. Vacca
We compute the growth of the mean square of quantum fluctuations of test fields with small effective mass during a slowly changing, nearly de Sitter stage which took place in different inflationary models. We consider a minimally coupled scalar with a small mass, a modulus with an effective mass $ \propto H^2$ (with $H$ as the Hubble parameter) and a massles
Piero Olla
The possibility of microscopic swimming by extraction of energy from an external flow is discussed, focusing on the migration of a simple trimer across a linear shear flow. The geometric properties of swimming, together with the possible generalization to the case of a vesicle, are analyzed.The mechanism of energy extraction from the flow appears to be the g
Yongmin Liu, Thomas Zentgraf, Guy Bartal, Xiang Zhang
Transformation optics has recently attracted extensive interest, since it provides a novel design methodology for manipulating light at will. Although transformation optics in principle embraces all forms of electromagnetic phenomena on all length scales, so far, much less efforts have been devoted to near-field optical waves, such as surface plasmon polarit
Paloma A. Huidobro, Maxim L. Nesterov, Luis Martin-Moreno, Francisco J. Garcia-Vidal
A new strategy to control the flow of surface plasmon polaritons at metallic surfaces is presented. It is based on the application of the concept of Transformation Optics to devise the optical parameters of the dielectric medium placed on top of the metal surface. We describe the general methodology for the design of Transformation-Optical devices for surfac
Tiago S. Machado, M. Argollo de Menezes, Tatiana G. Rappoport, Luiz C. Sampaio
We developed a method to calculate the magnetoresistance of magnetic nanostructures. We discretize a magnetic disk in small cells and numerically solve the Landau-Lifshitz-Gilbert (LLG) equation in order to obtain its magnetization profile. We consider a anisotropic magnetoresistance (AMR) that depends on the local magnetization as the main source of the mag
A Computationally Stable Approach to Gaussian Process Interpolation of Deterministic Computer Simulation Data
stat.MEPritam Ranjan, Ronald Haynes, Richard Karsten
For many expensive deterministic computer simulators, the outputs do not have replication error and the desired metamodel (or statistical emulator) is an interpolator of the observed data. Realizations of Gaussian spatial processes (GP) are commonly used to model such simulator outputs. Fitting a GP model to $n$ data points requires the computation of the in
Glencora Borradaile, Piotr Sankowski, Christian Wulff-Nilsen
For an undirected $n$-vertex planar graph $G$ with non-negative edge-weights, we consider the following type of query: given two vertices $s$ and $t$ in $G$, what is the weight of a min $st$-cut in $G$? We show how to answer such queries in constant time with $O(n\log^4n)$ preprocessing time and $O(n\log n)$ space. We use a Gomory-Hu tree to represent all th
Carl Fredrik Berg, Adam-Christiaan van Roosmalen
We introduce thread quivers as an (infinite) generalization of quivers, and show that every k-linear (k algebraically closed) hereditary category with Serre duality and enough projectives is equivalent to the category of finitely presented representations of a thread quiver. In this way, we obtain an explicit construction of a new class of hereditary categor
Scaling properties of one-dimensional cluster-cluster aggregation with Levy diffusion
physics.class-phColm Connaughton, Jamie Harris
We present a study of the scaling properties of cluster-cluster aggregation with a source of monomers in the stationary state when the spatial transport of particles occurs by Levy flights. We show that the transition from mean-field statistics to fluctuation-dominated statistics which, for the more commonly considered case of diffusive transport, occurs as
Frank Fiedler, Alexander Grohsjean, Petra Haefner, Philipp Schieferdecker
The most precise measurements of the top quark mass are based on the Matrix Element method. We present a detailed description of this analysis method, taking the measurements of the top quark mass in final states with one and two charged leptons as concrete examples. In addition, we show how the Matrix Element method is suitable to reduce the dominant system
R. Schlichenmaier, N. Bello Gonzalez, R. Rezaei, T. A. Waldmann
The generation of magnetic flux in the solar interior and its transport from the convection zone into the photosphere, the chromosphere, and the corona will be in the focus of solar physics research for the next decades. With 4m class telescopes, one plans to measure essential processes of radiative magneto-hydrodynamics that are needed to understand the nat
Analysis of Trace Impurities in Semiconductor Gas via Cavity-Enhanced Direct Frequency Comb Spectroscopy
physics.atom-phKevin C. Cossel, Florian Adler, Kris A. Bertness, Michael J. Thorpe
Cavity-enhanced direct frequency comb spectroscopy (CE-DFCS) has demonstrated powerful potential for trace gas detection based on its unique combination of high bandwidth, rapid data acquisition, high sensitivity, and high resolution, which is unavailable with conventional systems. However, previous demonstrations have been limited to proof-of-principle expe
Cornelius Weig, Torsten Ensslin
Reconstructing the matter density field from galaxy counts is a problem frequently addressed in current literature. Two main sources of error are shot noise from galaxy counts and insufficient knowledge of the correct galaxy position caused by peculiar velocities and redshift measurement uncertainty. Here we address the reconstruction problem of a Poissonian
Mark D. Roberts
The unique spherically symmetric metric which has vanishing weyl tensor, is asymptotically desitter, and can model constant galactic rotation curves is presented. Two types of field equations are shown to have this metric as an exact solution. The first is palatini varied scalar-tensor theory. The second is the low energy limit of string theory modified by i
Man Young Lee, Thomas Vojta
We investigate the generalized contact process with two absorbing states in one space dimension by means of large-scale Monte-Carlo simulations. Treating the creation rate of active sites between inactive domains as an independent parameter leads to a rich phase diagram. In addition to the conventional active and inactive phases we find a parameter region wh
Saul Ramos-Sanchez
We discuss recent developments on the solution of the so-called supersymmetric mu-problem in the context of heterotic orbifolds. In particular, an approximate R symmetry can induce an admissible mu-term in Minkowski vacua of orbifold models with the MSSM spectrum. A natural solution to the mu-problem is also offered by explicit string-derived NMSSMs. These m
Deog Ki Hong, Ho-Ung Yee
We study two aspects of 3D QCD with massless fermions in a holographic set-up from string theory, based on D3/D7 branes; parity anomaly and baryons as baby Skyrmions. We first give a novel account of parity anomaly of 3D QCD with odd number of flavors from the IR holographic viewpoint by observing a subtle point in D7 brane embeddings with a given fixed UV t
Envelope molecular-orbital theory of extended systems I. Electronic states of organic quasi-linear nano-heterostructures
cond-mat.mes-hallJulio C. Arce, Alejandro Perdomo-Ortiz, Martha L. Zambrano, Cesar A. Mujica-Martinez
A conceptually appealing and computationally economical course-grained molecular-orbital (MO) theory for extended quasi-linear molecular heterostructures is presented. The formalism, which is based on a straightforward adaptation, by including explicitly the vacuum, of the envelope-function approximation widely employed in solid-state physics, leads to a map
Benedikt Obermayer, Erwin Frey
The information content of a non-enzymatic self-replicator is limited by Eigen's error threshold. Presumably, enzymatic replication can maintain higher complexity, but in a competitive environment such a replicator is faced with two problems related to its twofold role as enzyme and substrate: as enzyme, it should replicate itself rather than wastefully
Ilarion V. Melnikov, M. Ronen Plesser
We study the linear sigma model subspace of the moduli space of (0,2) superconformal world-sheet theories obtained by deforming (2,2) theories based on Calabi-Yau hypersurfaces in reflexively plain toric varieties. We describe a set of algebraic coordinates on this subspace, formulate a (0,2) generalization of the monomial-divisor mirror map, and show that t
Tereza Krejcova, Jan Budaj, Viktoria Krushevska
Wasp-10b is a very interesting transiting extrasolar planet. Although its transit is very deep, about 40 mmag, there are very different estimates of its radius in the literature. We present new photometric observations of four complete transits of this planet. The whole event was detected for each transit and the final light curve consists of more than 1500
Soumen Mandal, Cécile Naud, Oliver A. Williams, Étienne Bustarret
We report on the transport properties of nanostructures made from boron-doped superconducting diamond. Starting from nanocrystalline superconducting boron-doped diamond thin films, grown by Chemical Vapor Deposition, we pattern by electron-beam lithography devices with dimensions in the nanometer range. We show that even for such small devices, the supercond
J. M. Baptista
We derive general expressions for the Kaehler form of the L^2-metric in terms of standard 2-forms on vortex moduli spaces. In the case of abelian vortices in gauged linear sigma-models, this allows us to compute explicitly the Kaehler class of the L^2-metric. As an application we compute the total volume of the moduli space of abelian semi-local vortices. In
Yuval Oreg, Gil Refael, Felix von Oppen
We show that the combination of spin-orbit coupling with a Zeeman field or strong interactions may lead to the formation of a helical liquid in single-channel quantum wires. In a helical liquid, electrons with opposite velocities have opposite spin precession. We argue that zero-energy Majorana bound states are formed in various situations when the wire is s
Victor Guba, Mark Sapir
To every finitely generated group one can assign the conjugacy growth function that counts the number of conjugacy classes intersecting a ball of radius $n$. Results of Ivanov and Osin show that the conjugacy growth function may be constant even if the (ordinary) growth function is exponential. The aim of this paper is to provide conjectures, examples and st
G. Vitagliano, A. Riera, J. I. Latorre
Entanglement entropy obeys area law scaling for typical physical quantum systems. This may naively be argued to follow from locality of interactions. We show that this is not the case by constructing an explicit simple spin chain Hamiltonian with nearest neighbor interactions that presents an entanglement volume scaling law. This non-translational model is c
Pieter Rozenhart, Michael Jacobson, Renate Scheidler
This paper presents an algorithm for generating all imaginary and unusual discriminants up to a fixed degree bound that define a quadratic function field of positive 3-rank. Our method makes use of function field adaptations of a method due to Belabas for finding quadratic number fields of high 3-rank and of a refined function field version of a theorem due
Jacopo Belfi, Giuseppe Bevilacqua, Valerio Biancalana, Roberto Cecchi
We describe a system for the compensation of time-dependent stray magnetic fields using a dual channel scalar magnetometer based on non-linear Faraday rotation in synchronously optically pumped Cs vapour. We detail the active control strategy, with an emphasis on the electronic circuitry, based on a simple phase-locked-loop integrated circuit. The performanc
A. A. Nucita, M. Guainazzi, A. L. Longinotti, M. Santos-Lleo
Soft X-rays high resolution spectroscopy of obscured AGNs shows the existence of a complex soft $X$-ray spectrum dominated by emission lines of He and H-like transitions of elements from Carbon to Neon, as well as L-shell transitions due to iron ions. In this paper we characterize the XMM-Newton RGS spectrum of the Seyfert 1 galaxy NGC 4051 observed during a
Alain-Sol Sznitman
The vacant set of random interlacements on ${\mathbb{Z}}^d$, $d\ge3$, has nontrivial percolative properties. It is known from Sznitman [Ann. Math. 171 (2010) 2039--2087], Sidoravicius and Sznitman [Comm. Pure Appl. Math. 62 (2009) 831--858] that there is a nondegenerate critical value $u_*$ such that the vacant set at level $u$ percolates when $u<u_*$ and do
Properties of linear integral equations related to the six-vertex model with disorder parameter
math-phHermann Boos, Frank Göhmann
One of the key steps in recent work on the correlation functions of the XXZ chain was to regularize the underlying six-vertex model by a disorder parameter $\alpha$. For the regularized model it was shown that all static correlation functions are polynomials in only two functions. It was further shown that these two functions can be written as contour integr
Markus Aichhorn, Silke Biermann, Takashi Miyake, Antoine Georges
The role of electronic Coulomb correlations in iron-based superconductors is an important open question. We provide theoretical evidence for strong correlation effects in the FeSe compound, based on dynamical mean field calculations. A lower Hubbard band is found in the spectral properties. Moreover, together with significant orbital-dependent mass enhanceme
A. V. Shavrina, Ya. V. Pavlenko, A. A. Veles, V. A. Sheminova
We report on ground-based FTIR observations being performed within the framework of the ESA-NIVR-KNMI project 2907 entitled "OMI validation by ground based remote sensing: ozone columns and atmospheric profiles" for the purpose of OMI data validation. FTIR observations were performed during the time frames August-October 2005, June-October 2006 and M
The nature of B supergiants: clues from a steep drop in rotation rates at 22000 K. The possibility of Bi-stability braking
astro-ph.SRJorick S. Vink, I. Brott, G. Graefener, N. Langer
The location of B supergiants in the Hertzsprung-Russell diagram (HRD) represents a long-standing problem in massive star evolution. Here we propose their nature may be revealed utilising their rotational properties, and we highlight a steep drop in massive star rotation rates at an effective temperature of 22000 K. We discuss two potential explanations for
C. A. de S. Pires, F. Queiroz, P. S. Rodrigues da Silva
In the original version of the minimal SU(3)_C x SU(3)_L x U(1)_N model the masses of all quarks are correctly obtained by introducing three scalar triplets into the model, meanwhile the lepton mass generation requires the introduction of at least one scalar sextet. In this work we show that this scalar sextet is unable to yield the correct neutrino masses a
Gautam Bhattacharyya, Tirtha Sankar Ray
Supersymmetry and extra dimension need not be mutually exclusive options of physics for the TeV scale and beyond. In this paper, we envisage a phenomenological scenario by embedding the 4d constrained minimal supersymmetric standard model in a flat 5d $S_1 /Z_2$ orbifold, with the inverse radius of compactification at the TeV scale. The gauge, Higgs and the
Diffuse-interface model for nanopatterning induced by self-sustained ion etch masking
cond-mat.mtrl-sciS. Le Roy, E. Søndergård, M. Kildemo, I. S. Nerbø
We construct a simple phenomenological diffuse-interface model for composition-induced nanopatterning during ion sputtering of alloys. In simulations, this model reproduces without difficulties the high-aspect ratio structures and tilted pillars observed in experiments. We investigate the time evolution of the pillar height, both by simulations and by {\it i
Novel mechanism for temperature-independent transitions in flexible molecules: role of thermodynamic fluctuations
cond-mat.stat-mechV. I. Teslenko, E. G. Petrov, A. Verkhratsky, O. A. Krishtal
Novel physical mechanism is proposed for explanation of temperature-independent transition reactions in molecular systems. The mechanism becomes effective in the case of conformation transitions between quasi-isoenergetic molecular states. It is shown that at room temperatures, stochastic broadening of molecular energy levels predominates the energy of low f
Edward A. Olszewski
We construct dyon solutions in SU(N) with topological electric and magnetic charge. Assuming a |Φ|^4-like potential for the Higgs field we show that the mass of the dyons is relatively insensitive to the coupling parameter λcharacterizing the potential. We then apply the methodology of constructing dyon solutions in SU(N) to G2. In order to define the electr
Brian P. Tighe, Erik Woldhuis, Joris J. C. Remmers, Wim van Saarloos
We probe flows of soft, viscous spheres near the jamming point, which acts as a critical point for static soft spheres. Starting from energy considerations, we find nontrivial scaling of velocity fluctuations with strain rate. Combining this scaling with insights from jamming, we arrive at an analytical model that predicts four distinct regimes of flow, each
Ulrike von Luxburg, Agnes Radl, Matthias Hein
Next to the shortest path distance, the second most popular distance function between vertices in a graph is the commute distance (resistance distance). For two vertices u and v, the hitting time H_{uv} is the expected time it takes a random walk to travel from u to v. The commute time is its symmetrized version C_{uv} = H_{uv} + H_{vu}. In our paper we stud
Jakob Scholbach
This paper studies Artin-Tate motives over number rings. As a subcategory of geometric motives, the triangulated category of Artin-Tate motives DATM(S) is generated by motives of schemes that are finite over the base S. After establishing stability of these subcategories under pullback and pushforward along open and closed immersions, a motivic t-structure i
A. M. Beloborodov, F. Daigne, R. Mochkovitch, Z. L. Uhm
The curvature of a relativistic blast wave implies that its emission arrives to observers with a spread in time. This effect is believed to wash out fast variability in the lightcurves of GRB afterglows. We note that the spreading effect is reduced if emission is anisotropic in the rest-frame of the blast wave (i.e. if emission is limb-brightened or limb-dar
Joakim Munkhammar
In this paper we suggest a connection between quantum mechanics and Verlinde's recently proposed entropic force theory for the laws of Newton. We propose an entropy based on the quantum mechanical probability density distribution. With the assumption that the holographic principle holds we propose that our suggested quantum entropy generalizes the Bekens
Ujjaini Alam
In this work, we study a class of early dark energy (EDE) models, in which, unlike in standard DE models, a substantial amount of DE exists in the matter-dominated era, self-consistently including DE perturbations. Our analysis shows that, marginalizing over the non DE parameters such as $Omega_m, H_0, n_s$, current CMB observations alone can constrain the s
András Némethi
We consider a connected negative definite plumbing graph, and we assume that the associated plumbed 3-manifold is a rational homology sphere. We provide two new combinatorial formulae for the Seiberg-Witten invariant of this manifold. The first one is the constant term of a `multivariable Hilbert polynomial', it reflects in a conceptual way the structure
S. K. Gorny, J. V. Perea-Calderon, D. A. Garcia-Hernandez, P. Garcia-Lario
We investigate Galactic bulge planetary nebulae without emission-line central stars for which peculiar infrared spectra have been obtained with the Spitzer Space Telescope, including the simultaneous signs of oxygen and carbon based dust. Three separate sub-groups can be defined characterized by the different chemical composition of the dust and the presence
Viswanath Gunturi, Shashi Shekhar, Arnab Bhattacharya
Given a spatio-temporal network (ST network) where edge properties vary with time, a time-sub-interval minimum spanning tree (TSMST) is a collection of minimum spanning trees of the ST network, where each tree is associated with a time interval. During this time interval, the total cost of tree is least among all the spanning trees. The TSMST problem aims to