April 2012 arXiv papers — page 5
Showing 401–500 of 6,637 papers
Time-Reversal Symmetry and Universal Conductance Fluctuations in a Driven Two-Level System
cond-mat.mes-hallSimon Gustavsson, Jonas Bylander, William D. Oliver
In the presence of time-reversal symmetry, quantum interference gives strong corrections to the electric conductivity of disordered systems. The self-interference of an electron wavefunction traveling time-reversed paths leads to effects such as weak localization and universal conductance fluctuations. Here, we investigate the effects of broken time-reversal
W. J. Stirling, E. Vryonidou
We study the polarisation of gauge bosons produced at the LHC. Polarisation effects for W bosons manifest themselves in the angular distributions of the lepton and in the distributions of lepton transverse momentum and missing transverse energy. The distributions also depend on the selection cuts, with kinematic effects competing with polarisation effects. T
Luigi Costamante
Very high energy (VHE) gamma-rays from extragalactic sources, interacting by gamma-gamma collisions with diffuse intergalactic radiation fields, provide an alternative way to constrain the diffuse background light, completely independent of direct measurements. The limits depend however on our knowledge of the physics of the gamma-ray sources. After clarifyi
Working characteristics of the New Low-Background Laboratory (DULB-4900, Baksan Neutrino Observatory)
physics.ins-detJu. M. Gavriljuk, A. M. Gangapshev, A. M. Gezhaev, V. V. Kazalov
A concise technical characteristic of a new low-background laboratory DULB-4900 of the BNO INR RAS is presented. The technique and the results of background measurements in the Hall, ordinary box and low-background box are presented. Rn-222 contamination in the laboratory air has been measured by direct detection of gamma-radiation of its daughter Bi-214 dis
Panagiotis Cheilaris, Shakhar Smorodinsky
Given a hypergraph H = (V, E), a coloring of its vertices is said to be conflict-free if for every hyperedge S \in E there is at least one vertex in S whose color is distinct from the colors of all other vertices in S. The discrete interval hypergraph Hn is the hypergraph with vertex set {1,...,n} and hyperedge set the family of all subsets of consecutive in
Validity of the Generalized Density Matrix Method for Microscopic Calculation of Collective/Bosonic Hamiltonian
nucl-thL. Y. Jia, V. G. Zelevinsky
Recently a procedure by generalized density matrix (GDM) is proposed for calculating a collective/bosonic Hamiltonian microscopically from the shell-model Hamiltonian. In this work we examine the validity of the method by comparing the GDM results with that of the exact shell-model diagonalization in a number of models. It is shown that the GDM method reprod
Dag Lukkassen, Annette Meidell, Klas Pettersson
For a periodically perforated structure, for which homogenization takes place in the linear theory of elasticity, the components of the effective elasticity tensor depend in general on the geometry of the holes as well as on the local elastic properties. These dependencies were shown by Vigdergauz in [7] to be separated in an elementary way for one particula
Yixing Wang, W. P. Pratt,, Norman O. Birge
Josephson junctions containing multiple ferromagnetic layers can carry spin-triplet supercurrent under certain conditions. Large-area junctions containing multiple domains are expected to have a random distribution of 0 or pi coupling across the junction surface, whereas magnetized samples should have uniquely pi coupling everywhere. We have measured the are
Rajdeep Borgohain
With the increase in the number of security threats, Intrusion Detection Systems have evolved as a significant countermeasure against these threats. And as such, the topic of Intrusion Detection Systems has become one of the most prominent research topics in recent years. This paper gives an overview of the Intrusion Detection System and looks at two major m
Michael Gr. Voskoglou
In this paper we develop a fuzzy model for the description of the process of Analogical Reasoning by representing its main steps as fuzzy subsets of a set of linguistic labels characterizing the individuals' performance in each step and we use the Shannon- Wiener diversity index as a measure of the individuals' abilities in analogical problem solving
High Repetition-Rate Wakefield Electron Source Generated by Few-millijoule, 30 femtosecond Laser Pulses on a Density Downramp
physics.plasm-phZ. -H. He, B. Hou, J. H. Easter, K. Krushelnick
We report on an experimental demonstration of laser wakefield electron acceleration using a sub-TW power laser by tightly focusing 30-fs laser pulses with only 8 mJ pulse energy on a 100 μm scale gas target. The experiments are carried out at an unprecedented 0.5 kHz repetition rate, allowing "real time" optimization of accelerator parameters. Well-c
The lead-glass electromagnetic calorimeters for the magnetic spectrometers in Hall C at Jefferson Lab
physics.ins-detH. Mkrtchyan, R. Carlini, V. Tadevosyan, J. Arrington
The electromagnetic calorimeters of the various magnetic spectrometers in Hall C at Jefferson Lab are presented. For the existing HMS and SOS spectrometers design considerations, relevant construction information, and comparisons of simulated and experimental results are included. The energy resolution of the HMS and SOS calorimeters is better than $σ/E \sim
Wolfgang Slany
Catroid is a free and open source visual programming language, programming environment, image manipulation program, and website. Catroid allows casual and first-time users starting from age eight to develop their own animations and games solely using their Android phones or tablets. Catroid also allows to wirelessly control external hardware such as Lego Min
LRS Bianchi type I universes exhibiting Noether symmetry in the scalar-tensor Brans-Dicke theory
gr-qcY. Kucukakca, U. Camci, İ. Semiz
Following up on hints of anisotropy in the cosmic microwave background radiation (CMB) data, we investigate locally rotational symmetric (LRS) Bianchi type I spacetimes with non-minimally coupled scalar fields. To single out potentially more interesting solutions, we search for Noether symmetry in this system. We then specialize to the Brans-Dicke (BD) field
Standing on the Shoulders of Their Peers: Success Factors for Massive Cooperation Among Children Creating Open Source Animations and Games on Their Smartphones
cs.CYTobias Gritschacher, Wolfgang Slany
We developed a website for kids where they can share new as well as remixed animations and games, e.g., interactive music videos, which they created on their smartphones or tablets using a visual "LEGO-style" programming environment called Catroid. Online communities for children like our website have unique requirements, and keeping the commitment o
Mathieu Molitor
Let (M,g) be a compact Riemannian manifold of dimension n. For k \in {0,...,n}, we denote Gr_{k}(M) the set of compact, connected and oriented submanifolds of M of dimension k. This set is called the non-linear Grassmannian. In this article, we endow Gr_{k}(M) with a smooth Fréchet manifold structure and investigate its basic geometrical properties. In parti
Low Frequency Dielectric Loss of Metal/Insulator/Organic Semiconductor Junctions in Ambient Conditions
cond-mat.mtrl-sciR. Ledru, S. Pleutin, B. Grouiez, D. Zander
The complex admittance of metal/oxide/pentacene thin film junctions is investigated under ambient conditions. At low frequencies, a contribution attributed to proton diffusion through the oxide is seen. This diffusion is shown to be anomalous and is believed to be also at the origin of the bias stress effect observed in organic field effect transistors. At h
Analytical studies of Hawking radiation and quasinormal modes in rotating linear dilatonic black hole
hep-thRan Li
The rotating linear dilatonic black hole is an asymptotically non-flat solution to Einstein-Maxwell-Dilaton-Axion gravity theory due to the existence of non-trivial matter fields. We have analytically studied the wave equation of scalar field in this background and shown that the radial wave equation can be solved in terms of hypergeometric function. By dete
Szymon Glab, Pedro L. Kaufmann, Leonardo Pellegrini
We show that the set of Lebesgue integrable functions in $[0,1]$ which are nowhere essentially bounded is spaceable, improving a result from [F. J. García-Pacheco, M. Martín, and J. B. Seoane-Sepúlveda. \textit{Lineability, spaceability, and algebrability of certain subsets of function spaces,} Taiwanese J. Math., \textbf{13} (2009), no. 4, 1257--1269], and
Daniele Treleani, Giorgio Calucci
The high rates of multi-parton interactions at the LHC can provide a unique opportunity to study the multi-parton structure of the hadron. To this purpose high energy collisions of protons with nuclei are particularly suitable. The rates of multi-parton interactions depend in fact both on the partonic multiplicities and on the distributions of partons in tra
Sergey M. Zagorodnyuk
In this paper we obtain some slight correction and generalization of the results of Ryabtseva on the generalized resolvents for isometric operators with a gap in their spectrum. Also, analogs of some McKelvey's results and a short proof of Inin's formula for the generalized resolvents of an isometric operator are obtained.
Anatoliy Zavdoveev, Yan Beygelzimer, Victor Varyukhin, Boris Efros
The image fractal analysis is actively used in all science branches. In particular in materials science the fractal analysis is applied to study microstructure of deformed metals because its structure can be interpreted as the fractal image. It is well known that such images can be described by fractal dimension. In this paper, the fractal dimension change f
A. Bouda, T. Foughali
In this paper, we propose a new deformed Poisson brackets which leads to the Fock coordinate transformation by using an analogous procedure as in Deformed Special Relativity. We therefore derive the corresponding momentum transformation which is revealed to be different from previous results. Contrary to the earlier version of Fock's nonlinear relativity
Roheet Bhatnagar, Mrinal Kanti Ghose
Accurately estimating the software size, cost, effort and schedule is probably the biggest challenge facing software developers today. It has major implications for the management of software development because both the overestimates and underestimates have direct impact for causing damage to software companies. Lot of models have been proposed over the yea
Laszlo P. Csernai, Gabriela Mocanu, Zoltan Neda
The dynamical development of the cooling and hadronizing quark-gluon Plasma (QGP) is studied in a simple model assuming critical fluctuations in the QGP to Hadronic Matter (HM) and a first order transition in a small finite system. We consider an earlier determined free-energy density curve in the neighbourhood of the critical point, with two local minima co
Suzaku Observation of Abell 1555 and Abell 1558: Searching for Non-thermal Emission from Large Scale Structure Formation
astro-ph.CORyu Makiya, Tomonori Totani, Kazuhiro Nakazawa
We report X-ray observations of two galaxy clusters Abell 1555 and Abell 1558 with Suzaku, which are included in a large scale filamentary structure and a supercluster, to search for non-thermal emission driven by shocks produced in structure formation. These two clusters are detected by Suzaku/XIS for the first time in the X-ray band of 0.5-7 keV. No signif
Corentin Herbert, Bérengère Dubrulle, Pierre-Henri Chavanis, Didier Paillard
Statistical mechanics provides an elegant explanation to the appearance of coherent structures in two-dimensional inviscid turbulence: while the fine-grained vorticity field, described by the Euler equation, becomes more and more filamented through time, its dynamical evolution is constrained by some global conservation laws (energy, Casimir invariants). As
Pavel Klavík, Jan Kratochvíl, Tomasz Krawczyk, Bartosz Walczak
Function graphs are graphs representable by intersections of continuous real-valued functions on the interval [0,1] and are known to be exactly the complements of comparability graphs. As such they are recognizable in polynomial time. Function graphs generalize permutation graphs, which arise when all functions considered are linear. We focus on the problem
Gia Dvali, Andre Franca, Cesar Gomez
We confront the concepts of Wilsonian UV-completion versus self-completion by Classicalization in theories with derivatively-coupled scalars. We observe that the information about the UV-completion road is encoded in the sign of the derivative terms. We note that the sign of the derivative couplings for which there is no consistent Wilsonian UV-completion is
Coupled Phonons, Magnetic Excitations and Ferroelectricity in AlFeO3: Raman and First-principles Studies
cond-mat.str-elPradeep Kumar, A. Bera, D. V. S. Muthu, S. N. Shirodkar
We determine the nature of coupled phonons and magnetic excitations in AlFeO3 using inelastic light scattering from 5 K to 315 K covering a spectral range from 100-2200 cm-1 and complementary first-principles density functional theory-based calculations. A strong spin-phonon coupling and magnetic ordering induced phonon renormalization are evident in (a) ano
Wolfgang Herfort, Pavel A. Zalesskii
We fill details in the proof of Lemma 13 in Bull.London.Math.Soc 40 (2008) (that is Lemma 3.2 in arXiv:0712.4244v1).
Yankui Sun, Tian Zhang
With the introduction of spectral-domain optical coherence tomography (OCT), much larger image datasets are routinely acquired compared to what was possible using the previous generation of time-domain OCT. Thus, the need for 3-D segmentation methods for processing such data is becoming increasingly important. We present a new 3D segmentation method for reti
J. S. Pelc, G. -L. Shentu, Q. Zhang, M. M. Fejer
Multi-longitudinal-mode lasers have been believed to be good candidates as pump sources for optical frequency conversion. However, we present a semi-classical model for frequency conversion of optical signals with a multimode pump laser, which shows that fluctuations of the instantaneous pump power limit the conversion efficiency. In an experiment, we upconv
Jun Masamune, Toshihiro Uemura, Jian Wang
Sufficient conditions for a symmetric jump-diffusion process to be conservative and recurrent are given in terms of the volume of the state space and the jump kernel of the process. A number of examples are presented to illustrate the optimality of these conditions; in particular, the situation is allowed to be that the state space is topologically disconnec
Simon Gustavsson, Fei Yan, Jonas Bylander, Fumiki Yoshihara
We implement dynamical decoupling techniques to mitigate noise and enhance the lifetime of an entangled state that is formed in a superconducting flux qubit coupled to a microscopic two-level system. By rapidly changing the qubit's transition frequency relative to the two-level system, we realize a refocusing pulse that reduces dephasing due to fluctuati
E. Weinan, Jianfeng Lu, Yuan Yao
Topological landscape is introduced for networks with functions defined on the nodes. By extending the notion of gradient flows to the network setting, critical nodes of different indices are defined. This leads to a concise and hierarchical representation of the network. Persistent homology from computational topology is used to design efficient algorithms
Tim Browning, Alan Haynes
We investigate the solubility of the congruence xy=1 (mod p), where p is a prime and x,y are restricted to lie in suitable short intervals. Our work relies on a mean value theorem for incomplete Kloosterman sums.
Lamei Yuan, Hong You
The purpose of this paper is to study Hom-Novikov algebras and Hom-Novikov-Poisson algebras, both of which were defined by Yau. In the paper, we give several constructions leading us to some interesting examples of Hom-Novikov algebras and Hom-Novikov-Poisson algebras. Also, we introduce the notion of quadratic Hom-Novikov algebras and provide some propertie
Sergey Sushkov
We investigate cosmological scenarios in the theory of gravity with the scalar field possessing a non-minimal kinetic coupling to the curvature. It is shown that the kinetic coupling provides an essentially new inflationary mechanism. Namely, at early cosmological times the domination of coupling terms in the field equations guarantees the quasi-De Sitter be
M. Neek-Amal, L. Covaci, F. M. Peeters
Recent experiments showed that non-uniform strain can be produced by depositing graphene over pillars. We employed atomistic calculations to study the non-uniform strain and the induced pseudo-magnetic field up to 5000 Tesla in graphene on top of nano-pillars. By decreasing the distance between the nano-pillars a complex distribution for the pseudo-magnetic
M. Neek-Amal, F. M. Peeters
Using atomistic simulations we investigate the morphological properties of graphene deposited on top of a nanostructured substrate. Sinusoidally corrugated surfaces, steps, elongated trenches, one dimensional and cubic barriers, spherical bubbles, Gaussian bump and Gaussian depression are considered as support structures for graphene. The graphene-substrate
First Principles Quantum Transport with Electron-vibration Interactions: A Maximally Localized Wannier Function Approach
cond-mat.mes-hallSejoong Kim, Nicola Marzari
We present an ab initio inelastic quantum transport approach based on maximally localized Wannier functions. Electronic-structure properties are calculated with density-functional theory in a planewave basis, and electron-vibration coupling strengths and vibrational properties are determined with density-functional perturbation theory. Vibration-induced inel
Strain engineered graphene using a nanostructured substrate: II Pseudo-magnetic fields
cond-mat.mes-hallM. Neek-Amal, F. M. Peeters
The strain induced pseudo-magnetic field in supported graphene deposited on top of a nanostructured substrate is investigated by using atomistic simulations. Step, elongated trench, one dimensional barrier, spherical bubbles, Gaussian bump and Gaussian depression are considered as support structures for graphene. From the obtained optimum configurations we f
A GPU Tool for Efficient, Accurate, and Realistic Simulation of Cone Beam CT Projections
physics.med-phXun Jia, Hao Yan, Laura Cervino, Michael Folkerts
Simulation of x-ray projection images plays an important role in cone beam CT (CBCT) related research projects. A projection image contains primary signal, scatter signal, and noise. It is computationally demanding to perform accurate and realistic computations for all of these components. In this work, we develop a package on GPU, called gDRR, for the accur
Rushdi Shams, Adel Elsayed, Quazi Mah-Zereen Akter
The aim of this paper is to evaluate a Text to Knowledge Mapping (TKM) Prototype. The prototype is domain-specific, the purpose of which is to map instructional text onto a knowledge domain. The context of the knowledge domain is DC electrical circuit. During development, the prototype has been tested with a limited data set from the domain. The prototype re
A Corpus-based Evaluation of Lexical Components of a Domainspecific Text to Knowledge Mapping Prototype
cs.IRRushdi Shams, Adel Elsayed
The aim of this paper is to evaluate the lexical components of a Text to Knowledge Mapping (TKM) prototype. The prototype is domain-specific, the purpose of which is to map instructional text onto a knowledge domain. The context of the knowledge domain of the prototype is physics, specifically DC electrical circuits. During development, the prototype has bee
Curtis Bennett, Edward Mosteig
We analyze congruence classes of $S(n,k)$, the Stirling numbers of the second kind, modulo powers of 2. This analysis provides insight into a conjecture posed by Amdeberhan, Manna and Moll, which those authors established for $k\le5$. We provide a framework that can be used to justify the conjecture by computational means, which we then complete for $k=5, 6,
M. Todd, P. Tanga, D. M. Coward, M. G. Zadnik
Trojan asteroids are minor planets that share the orbit of a planet about the Sun and librate around the L4 or L5 Lagrangian points of stability. Although only three Mars Trojans have been discovered, models suggest that at least ten times this number should exist with diameters >= 1 km. We derive a model that constrains optimal sky search areas and present
Direct Observation of Inner and Outer G' Band Double-resonance Raman Scattering in Free Standing Graphene
cond-mat.mtrl-sciZhiqiang Luo, Chunxiao Cong, Jun Zhang, Qihua Xiong
In contrary to the widely reported single and symmetric peak feature of G' (or 2D) band in Raman spectrum of graphene, we herein report the observation of splitting in G' band in free standing graphene. Our experimental findings provide a direct and strong support for the previous theoretical prediction that the coexistence of the outer and inner pro
Nanbo Peng, Yanxia Zhang, Yongheng Zhao, Xuebing Wu
We develop and demonstrate a classification system constituted by several Support Vector Machines (SVM) classifiers, which can be applied to select quasar candidates from large sky survey projects, such as SDSS, UKIDSS, GALEX. How to construct this SVM classification system is presented in detail. When the SVM classification system works on the test set to p
Ted Jacobson
The vacuum of quantum fields contains correlated fluctuations. When restricted to one side of a surface these have a huge entropy of entanglement that scales with the surface area. If UV physics renders this entropy finite, then a thermodynamic argument implies the existence of gravity. That is, the causal structure of spacetime must be dynamical and governe
An Input-Output Simulation Approach to Controlling Multi-AffineSystems for Linear Temporal Logic Specifications
eess.SYYajuan Sun, Hai Lin, Ben M. Chen
This paper presents an input-output simulation approach to controlling multi-affine systems for linear temporal logic (LTL) specifications, which consists of the following steps. First, we partition the state space into rectangles, each of which satisfies atomic LTL propositions. Then, we study the control of multi-affine systems on rectangles including the
Prediction of polaron-like vortices and dissociation depinning transition in magnetic superconductors: The example of ErNi2B2C
cond-mat.supr-conLev N. Bulaevskii, Shi-Zeng Lin
In borocarbide ErNi$_2$B$_2$C the phase transition to the commensurate spin density wave at 2.3 K leaves 1/20 part of Ising-like Er spins practically free. Vortices polarize these spins nonuniformly and repolarize them when moving. At a low spin relaxation rate and at low bias currents vortices carrying magnetic polarization clouds become polaron-like and th
Energetically stable singular vortex cores in an atomic spin-1 Bose-Einstein condensate
cond-mat.quant-gasJustin Lovegrove, Magnus O. Borgh, Janne Ruostekoski
We analyze the structure and stability of singular singly quantized vortices in a rotating spin-1 Bose-Einstein condensate. We show that the singular vortex can be energetically stable in both the ferromagnetic and polar phases despite the existence of a lower-energy nonsingular coreless vortex in the ferromagnetic phase. The spin-1 system exhibits an energe
Junghoon Lee, Cihan Tepedelenlioglu
Stochastic orders are binary relations defined on probability distributions which capture intuitive notions like being larger or being more variable. This paper introduces stochastic ordering of interference distributions in large-scale networks modeled as point process. Interference is the main performance-limiting factor in most wireless networks, thus it
Transition probability of perturbative form for nu_mu -> nu_e oscillations in matter of constant density
hep-phW. Anthony Mann, Tomas Kafka, Jacob Schneps, Ozgur Altinok
We give a convenient expression for the appearance probability P(nu_mu -> nu_e) describing neutrino oscillations in matter of constant density, derived using textbook quantum mechanics stratagems. Our formulation retains the clarity of an expansion in alpha = Delta m_{21}^2/Delta m_{31}^2 exhibited by the popular Cervera et al. formula [Nucl. Phys. B 579, 17
Oleksii Matsedonskyi, Giuliano Panico, Andrea Wulzer
Anomalously light fermionic partners of the top quark often appear in explicit constructions, such as the 5d holographic models, where the Higgs is a light composite pseudo Nambu-Goldstone boson and its potential is generated radiatively by top quark loops. We show that this is due to a structural correlation among the mass of the partners and the one of the
S. Mondal, D. Pekker, K. Sengupta
We study the non-equilibrium dynamics of ultracold bosons in an optical lattice with a time dependent hopping amplitude J(t)=J_0 +δJ \cos(ωt) which takes the system from a superfluid phase near the Mott-superfluid transition (J= J_0+δJ) to a Mott phase (J=J_0-δJ) and back through a quantum critical point (J=J_c) and demonstrate dynamic freezing of the boson
Hui-Yiing Chang, Robert J. Scherrer
We examine cyclic phantom models for the universe, in which the universe is dominated sequentially by radiation, matter, and a phantom dark energy field, followed by a standard inflationary phase. Since this cycle repeats endlessly, the Universe spends a substantial portion of its lifetime in a state for which the matter and dark energy densities have compar
Jose L. Goity, Roberto C. Trinchero
Five dimensional dilaton models are considered as possible holographic duals of the pure gauge QCD vacuum. In the framework of these models, the QCD trace anomaly equation is considered. Each quantity appearing in that equation is computed by holographic means. Two exact solutions for different dilaton potentials corresponding to perturbative and non-perturb
Jean-Philippe Jodoin, Guillaume-Alexandre Bilodeau, Nicolas Saunier
We present a novel approach to background subtraction that is based on the local shape of small image regions. In our approach, an image region centered on a pixel is mod-eled using the local self-similarity descriptor. We aim at obtaining a reliable change detection based on local shape change in an image when foreground objects are moving. The method first
Konstantinos Chorianopoulos, Vassiliki Tsaknaki
We explore the design of a seamless broadcast communication system that brings together the distributed community of remote secondary education schools. In contrast to higher education, primary and secondary education establishments should remain distributed, in order to maintain a balance of urban and rural life in the developing and the developed world. We
Jorge Noreña, Licia Verde, Gabriela Barenboim, Cristian Bosch
We consider whether the non-Gaussian scale-dependent halo bias can be used not only to constrain the local form of non-Gaussianity but also to distinguish among different shapes. In particular, we ask whether it can constrain the behavior of the primordial three-point function in the squeezed limit where one of the momenta is much smaller than the other two.
Eric C. Andrade, Matthias Vojta
Hour-glass-shaped magnetic excitation spectra have been detected in a variety of doped transition-metal oxides with stripe-like charge order. Compared to the predictions of spin-wave theory, these spectra display a different intensity distribution and anomalous broadening. Here we show, based on a comprehensive modelling of these phenomena for La5/3Sr1/3CoO4
Wladimir Lyra, Marc J. Kuchner
Debris disks should not be completely gas-free, since there is second generation gas from outgassing of planetesimals and dust grains via sublimation, photodesorption, or collisions, generating a system of dust-to-gas ratio close to unity, where hydrodynamics cannot be ignored. A clumping instability exists in this configuration, that has been hitherto explo
Tom McCavana, Miroslav Micic, Geraint F. Lewis, Manodeep Sinha
We present a comparative study of recent works on merger-timescales with dynamical friction and find a strong contrast between idealized/isolated mergers (Boylan-Kolchin et al. 2008) and mergers from a cosmological volume (Jiang et al. 2008). Our study measures the duration of mergers in a cosmological N-body simulation of dark matter, with emphasis on highe
Joo Heon Yoon, Mary Putman, Christopher Thom, Hsiao-Wen Chen
The first systematic study of the warm gas (T=10^4-5 K) distribution across a galaxy cluster is presented using multiple background QSOs to the Virgo Cluster. We detect 25 Lya absorbers (N_HI = 10^13.1-15.4 cm^-2) in the Virgo velocity range toward 9 of 12 QSO sightlines observed with Cosmic Origin Spectrograph, with a cluster impact parameter range of 0.36-
Steven S. Gubser, Jie Ren
We find exact, analytic solutions of the Dirac equation for a charged, massless fermion in the background of a charged, dilatonic black hole in AdS_5. The black hole descends from type IIB supergravity, where it describes D3-branes with equal angular momenta in two of the three independent planes of rotation orthogonal to the world-volume. The Green's fu
Victor Alexandrov, Piers Coleman
In this paper we discuss two-dimensional holographic metals from a condensed matter physics perspective. We examine the spin structure of the Green's function of the holographic metal, demonstrating that the excitations of the holographic metal are "chiral", lacking the inversion symmetry of a conventional Fermi surface, with only one spin orient
Paul M. Hohler, Ralf Rapp
We simultaneously analyze vector and axial-vector spectral functions in vacuum using hadronic models constrained by experimental data and the requirement that Weinberg-type sum rules are satisfied. Upon explicit inclusion of an excited vector state, viz. rho', and the requirement that the perturbative continua are degenerate in vector and axial-vector ch
Jay M. Gambetta, A. D. Corcoles, S. T. Merkel, B. R. Johnson
The control and handling of errors arising from cross-talk and unwanted interactions in multi-qubit systems is an important issue in quantum information processing architectures. We introduce a benchmarking protocol that provides information about the amount of addressability present in the system and implement it on coupled superconducting qubits. The proto
N. Grosjean, J. M. Maillet, G. Niccoli
We develop a method for computing form factors of local operators in the framework of Sklyanin's separation of variables (SOV) approach to quantum integrable systems. For that purpose, we consider the sine-Gordon model on a finite lattice and in finite dimensional cyclic representations as our main example. We first build our two central tools for comput
Joseph Plowman, Charles Kankelborg, Petrus Martens
We present a fast method for reconstructing Differential Emission Measures (DEMs) using solar coronal data. On average, the method computes over 1000 DEMs per second for a sample active region observed by the Atmospheric Imaging Assembly (AIA) on the Solar Dynamics Observatory (SDO), and achieves reduced chi-squared of order unity with no negative emission i
Closing the Loop: A Self-Consistent Model of Optical, X-ray, and SZ Scaling Relations for Clusters of Galaxies
astro-ph.COEduardo Rozo, James G. Bartlett, August E. Evrard, Eli S. Rykoff
We demonstrate that optical data from SDSS, X-ray data from ROSAT and Chandra, and SZ data from Planck, can be modeled in a fully self-consistent manner. After accounting for systematic errors and allowing for property covariance, we find that scaling relations derived from optical and X-ray selected cluster samples are consistent with one another. Moreover,
E. Hatefi, A. J. Nurmagambetov, I. Y. Park
In this paper, which is a companion to ArXiv:1204.2711[hep-th], we formulate a criterion for constructing 11D/10D maximal supergravity black-brane solutions with the near-extremal $S\sim n^3T^5$ entropy-temperature relation. We present explicit examples of such solutions with special attention paid to thermodynamics of black M-waves (KK-waves), intersecting/
Brian K. Butler, Paul H. Siegel
The spectral radius ρ(G) of a digraph G is the maximum modulus of the eigenvalues of its adjacency matrix. We present bounds on ρ(G) that are often tighter and are applicable to a larger class of digraphs than previously reported bounds. Calculating the final bound pair is particularly suited to sparse digraphs. For strongly connected digraphs, we derive equ
Quantum optomechanics with a high-frequency dilational mode in thin dielectric membranes
cond-mat.mes-hallK. Borkje, S. M. Girvin
The interaction between a high-frequency dilational mode of a thin dielectric film and an optical cavity field is studied theoretically in the membrane-in-the-middle setup. A derivation from first principles leads to a multi-mode optomechanical Hamiltonian where multiple cavity modes are coupled by the thickness variation of the membrane. For membrane thickn
Cheng-Wei Chiang, Gaber Faisel, Yi-Fan Lin, Jusak Tandean
We consider nonstandard interactions of neutrinos with electrons arising from a new light spin-1 particle with mass of tens of GeV or lower and couplings to the neutrinos and electron. This boson is not necessarily a gauge boson and is assumed to have no mixing with standard-model gauge bosons. Adopting a model-independent approach, we study constraints on t
S. I. Kruglov
A modified theory of gravity with the function $F(R) = R\exp(αR)$ instead of Ricci scalar $R$ in the Einstein$-$Hilbert action is considered and analyzed. The action of the model is converted into Einstein$-$Hilbert action at small value of the parameter $α$. From local tests we obtain a bound on the parameter $α\leq 10^{-6}$ cm$^2$. The Jordan and Einstein
Eduardo Rozo, August E. Evrard, Eli S. Rykoff, James G. Bartlett
We compare cluster scaling relations published for three different samples selected via X-ray and Sunyaev-Zel'dovich (SZ) signatures. We find tensions driven mainly by two factors: i) systematic differences in the X-ray cluster observables used to derive the scaling relations, and ii) uncertainty in the modeling of how the gas mass of galaxy clusters sca
Paolo Benincasa, Alfonso V. Ramallo
We study the addition of localised impurities to U(N) Supersymmetric Yang-Mills theories in (p+1)-dimensions by using the gauge/gravity correspondence. From the gravity side, the impurities are introduced by considering probe D(8-p)-branes extendingalong the time and radial directions and wrapping an (7-p)-dimensional submanifold of the internal (8-p)-sphere
Masafumi Fukuma, Yuho Sakatani
We present a generally covariant formulation of conformal higher-order viscoelastic fluid mechanics with strain allowed to take arbitrarily large values. We give a general prescription to determine the dynamics of a relativistic viscoelastic fluid in a way consistent with the hypothesis of local thermodynamic equilibrium and the second law of thermodynamics.
J. R. Barnes, J. S. Jenkins, H. R. A. Jones, P. Rojo
We present the first results from our Red Optical Planet Survey (ROPS) to search for low mass planets orbiting late type dwarfs (M5.5V - M9V) in their habitable zones (HZ). Our observations, with the red arm of the MIKE spectrograph (0.5 - 0.9 microns) at the 6.5 m Magellan Clay telescope at Las Campanas Observatory indicate that >= 92 per cent of the flux l
D. Smirnov, H. Schmidt, R. J. Haug
Aharonov-Bohm oscillations are observed in a graphene quantum ring with a top gate covering one arm of the ring. As graphene is a gapless semiconductor this geometry allows to study not only the quantum interference of electrons with electrons or holes with holes but also the unique situation of quantum interference between electrons and holes. The period an
D. Kotschick
Generalizing the theorem of Green--Lazarsfeld and Gromov, we classify Kaehler groups of deficiency at least two. As a consequence we see that there are no Kaehler groups of even and strictly positive deficiency. With the same arguments we prove that Kaehler groups that are non-Abelian and are limit groups in the sense of Sela are surface groups.
Antoine Chambert-Loir, Antoine Ducros
We define a theory of real $(p,q)$-forms and currents on Berkovich spaces which is parallel to the theory of differential forms on complex spaces. It is based on Lagerberg's theory of superforms in tropical geometry and on the consideration of tropicalization maps and skeleta on domains of non archimedean analytic spaces in the sense of Berkovich. We con
Junji Hisano, Daiki Kobayashi, Natsumi Nagata
In the supersymmetric grand unified theories (SUSY GUTs), gauge bosons associated with the unified gauge group induce proton decay. We investigate the proton decay rate via the gauge bosons in the SUSY GUTs under the two situations; one is with extra vector-like multiplets, and the other is with heavy sfermions. It is found that the proton lifetime is signif
Rafael Ferraro
We briefly review f(R) theories, both in the metric and Palatini formulations, their scalar-tensor representations and the chameleon mechanism that could explain the absence of perceptible consequences in the Solar System. We also review f(T) theories, a different approach to modified gravity consisting in a deformation of the teleparallel equivalent of Gene
Eduardo Martin-Martinez, Dominic Hosler, Miguel Montero
We study communication between an inertial observer and one of two causally-disconnected counter accelerating observers. We will restrict the quantum channel considering inertial-to-accelerated bipartite classical and quantum communication over different sets of Unruh modes (single-rail or dual-rail encoding). We find that the coherent information (and there
Freddy Bouchet, Hugo Touchette
We study the large deviations of a simple noise-perturbed dynamical system having continuous sets of steady states, which mimick those found in some partial differential equations related, for example, to turbulence problems. The system is a two-dimensional nonlinear Langevin equation involving a dissipative, non-potential force, which has the essential effe
Daniele Colosi, Dennis Raetzel
In the framework of the general boundary formulation (GBF) of scalar quantum field theory we obtain a coincidence of expectation values of local observables in the Minkowski vacuum and in a particular state in Rindler space. This coincidence could be seen as a consequence of the identification of the Minkowski vacuum as a thermal state in Rindler space usual
Kevin McGoff, Sayan Mukherjee, Natesh S. Pillai
The topic of statistical inference for dynamical systems has been studied extensively across several fields. In this survey we focus on the problem of parameter estimation for non-linear dynamical systems. Our objective is to place results across distinct disciplines in a common setting and highlight opportunities for further research.
Dorothea Bahns, Katarzyna Rejzner, Jochen Zahn
We show that the Nambu-Goto string, and its higher dimensional generalizations, can be quantized, in the sense of an effective theory, in any dimension of the target space. The crucial point is to consider expansions around classical string configurations. We are using tools from perturbative algebraic quantum field theory, quantum field theory on curved spa
Adrien Hardy, Arno B. J. Kuijlaars
We investigate an additive perturbation of a complex Wishart random matrix and prove that a large deviation principle holds for the spectral measures. The rate function is associated to a vector equilibrium problem coming from logarithmic potential theory, which in our case is a quadratic map involving the logarithmic energies, or Voiculescu's entropies,
T. Marketin, E. Litvinova, D. Vretenar, P. Ring
An extension of time-dependent covariant density functional theory that includes particle-vibration coupling is applied to the charge-exchange channel. Spin-dipole excitation spectra are calculated an compared to available data for $^{90}$Zr and $^{208}$Pb. A significant fragmentation is found for all three angular-momentum components of the spin-dipole stre
Level spacings for weakly asymmetric real random matrices and application to two-color QCD with chemical potential
hep-latJacques Bloch, Falk Bruckmann, Nils Meyer, Sebastian Schierenberg
We consider antisymmetric perturbations of real symmetric matrices in the context of random matrix theory and two-color quantum chromodynamics. We investigate the level spacing distributions of eigenvalues that remain real or become complex conjugate pairs under the perturbation. We work out analytical surmises from small matrices and show that they describe
Steven L. Kleiman, Vivek V. Shende, with an appendix by Ilya Tyomkin
For a line bundle L on a smooth surface S, it is now known that the degree of the Severi variety of cogenus-d curves is given by a universal polynomial in the Chern classes of L and S if L is d-very ample. For S rational, we relax the latter condition substantially: it suffices that three key loci be of codimension more than d. As corollaries, we prove that
M. Hoferichter, C. Ditsche, B. Kubis, U. -G. Meißner
Based on the recently proposed Roy-Steiner equations for pion-nucleon scattering, we derive a system of coupled integral equations for the pi pi --> N-bar N and K-bar K --> N-bar N S-waves. These equations take the form of a two-channel Muskhelishvili-Omnes problem, whose solution in the presence of a finite matching point is discussed. We use these results
Sergey V. Petoukhov
The conception of multi-alphabetical genetics is represented. Matrix forms of the representation of the multi-level system of molecular-genetic alphabets have revealed algebraic properties of this system. These properties are connected with well-known notions of dyadic groups and dyadic-shift matrices. Matrix genetics shows relations of the genetic alphabets
The Meissner effect in a strongly underdoped cuprate above its critical temperature
cond-mat.supr-conElvezio Morenzoni, Bastian M. Wojek, Andreas Suter, Thomas Prokscha
The Meissner effect and the associated perfect "bulk" diamagnetism together with zero resistance and gap opening are characteristic features of the superconducting state. In the pseudogap state of cuprates unusual diamagnetic signals as well as anomalous proximity effects have been detected but a Meissner effect has never been observed. Here we have