April 2009 arXiv papers — page 5
Showing 401–500 of 4,924 papers
Comparison of EIT schemes in semiconductor quantum dot structures: Impact of many-body interactions
cond-mat.mes-hallJ. Houmark, T. R. Nielsen, J. Mork, A. -P. Jauho
We investigate the impact of many-body interactions on group-velocity slowdown achieved via electromagnetically induced transparency in quantum dots using three different coupling-probe schemes (ladder, V, and Lambda, respectively). We find that for all schemes many-body interactions have an important impact on the slow light properties. In the case of the L
Steffen Waldherr, Rolf Findeisen, Frank Allgöwer
We study the problem of computing outer bounds for the region of steady states of biochemical reaction networks modelled by ordinary differential equations, with respect to parameters that are allowed to vary within a predefined region. Using a relaxed version of the corresponding feasibility problem and its Lagrangian dual, we show how to compute certificat
J. Nieves, E. Ruiz Arriola
The rigorous quantum mechanical definition of a resonance requires determining the pole position in the second Riemann sheet of the analytically continued partial wave scattering amplitude in the complex Mandelstam s-variable plane. For meson resonances we investigate the alternative Breit-Wigner (BW) definition within the large Nc expansion. By assuming tha
Juan-Manuel Torres-Moreno, Mirta B. Gordon
A efficient incremental learning algorithm for classification tasks, called NetLines, well adapted for both binary and real-valued input patterns is presented. It generates small compact feedforward neural networks with one hidden layer of binary units and binary output units. A convergence theorem ensures that solutions with a finite number of hidden units
Stavros D. Peroukidis, Panagiota K. Karahaliou, Alexandros G. Vanakaras, D. J. Photinos
We study the symmetry and the spatial uniformity of orientational order of the biaxial nematic phase in the light of recent experimental observations of phase biaxiality in thermotropic bent-core and calamitic-tetramer nematics. We present evidence supporting monoclinic symmetry, instead of the usually assumed orthorhombic. We describe the use of deuterium N
Donat J. Adams, Bernard Amadon
Rare earth (R) orthoferrites RFeO_3 exhibit large volume transitions associated with a spin collapse. We present here ab initio calculations on LuFeO_3. We show that taking into account the strong correlation among the Fe-3d electrons is necessary. Indeed, with the LDA+U method in the Projector Augmented Wave (PAW), we are able to describe the isostructural
Canonical Torsion-Free Connections on the Total Space of the Tangent and the Cotangent Bundle
math.RTLionel Bérard Bergery, Thomas Krantz
In this paper we define a class of torsion-free connections on the total space of the (co-)tangent bundle over a base-manifold with a connection and for which tangent spaces to the fibers are parallel. Each tangent space to a fiber is flat for these connections and the canonical projection from the (co-)tangent bundle to the base manifold is totally geodesic
Mateusz Michalek
In this note we give a short, direct proof of the well known Combinatorial Nullstellensatz.
V. A. Novikov, A. N. Rozanov, M. I. Vysotsky
Precision measurements of $Z$-boson parameters and $W$-boson and $t$-quark masses put strong constraints on non $SU(2)\times U(1)$ singlet New Physics. We demonstrate that one extra generation passes electroweak constraints even when all new particle masses are well above their direct mass bounds.
Hartmut Weiss
We give a new and detailed proof of the variation formulas for the equivariant Ray-Singer metric, which are originally due to J.M. Bismut and W. Zhang.
The dynamics of individual nucleosomes controls the chromatin condensation pathway: direct AFM visualization of variant chromatin
physics.bio-phFabien Montel, Hervé Menoni, Martin Castelnovo, Jan Bednar
Chromatin organization and dynamics is studied in this work at scales ranging from single nucleosome to nucleosomal array by using a unique combination of biochemical assays, single molecule imaging technique and numerical modeling. We demonstrate that a subtle modification in the nucleosome structure induced by the histone variant H2A.Bbd drastically modifi
Li-Bo Chen, Peng Shi, Yong-Jian Gu, Lin Xie
We propose schemes to prepare atomic entangled states in a bi-mode cavity via stimulated Raman adiabatic passage (STIRAP) and fractional stimulated Raman adiabatic passage (f-STIRAP) tech- niques. According to the simulation results, our schemes keep the cavity modes almost unexcited and the atomic excited states are nearly unpopulated during the whole proce
Yashonidhi Pandey
Let $π: Z \to X$ be Galois cover of smooth projective curves with Galois group $W$ a Weyl group of a simple Lie group $G$. For a dominant weight $λ$, we consider the intermediate curve $Y_λ= Z/\Stab(λ)$. One can realise a Prym variety $P_λ\subset \Jac(Y_λ)$ and we denote $φ_λ$ the restriction of the principal polarisation of $\Jac(Y_λ)$ upon $P_λ$. For two d
Yashonidhi Pandey
Let $W$ be a finite group and $T$ be an abelian group. Consider an extension $0 \ra T \ra N \ra W \ra 0$. For a smooth projective curve $X$, we give a precise description of the fiber of the quotient by $T$ map $q_T: \cM_X(N) \ra \cM_X(W)$ as a torsor over an abelian variety. We also prove a result on Mumford groups.
Hitoshi Murayama, Vikram Rentala
Quantum interference of helicity amplitudes provides a powerful tool for measuring the spins of new particles. By looking at the azimuthal angular dependence of the differential cross-section in the production followed by decay of a new particle species one can determine its spin by looking at the various cosine modes. The heavy spin-2 Kaluza-Klein (KK) grav
Bianca M. Poggianti, Alfonso Aragon-Salamanca, Steven Bamford, Fabio Barazza
The ESO Distant Cluster Survey (EDisCS, P.I. Simon D.M. White, LP 166.A-0162) is an ESO large programme aimed at studying clusters and cluster galaxies at z=0.4-1. How different is the evolution of the star formation activity in clusters, in groups and in the field? Does it depend on cluster mass and/or the local galaxy density? How relevant are starburst an
Olga Bernardi, Franco Cardin
For evolutive Hamilton-Jacobi equations, we propose a refined definition of C^0-variational solution, adapted to Cauchy problems for continuous initial data. In this weaker framework we investigate the Markovian (or semigroup) property for these solutions. In the case of p-convex Hamiltonians, when variational solutions are known to be identical to viscosity
Sarben Sarkar
The possible role of decoherence due to space-time foam is discussed within the context of two models, one based on string/brane theory. and the other based on properties of black hole horizons in general relativity. It is argued that the density matrix satisfies a dissipative master equation, primarily from the study of renormalization group flows in non-cr
Patrice Medina, Cayetano Santos, Denis Villaume
A functional approach to the concept of pulse shape synthesis introduced here. This paper reviews some of the mechanisms influencing the process of signal induction, and the solution of electric field and charge carriers drift phenoma are considered for abritrary crystal geometries. Then, preforming some well known principles and a set of simple techniques p
Sourish Dutta, Tanmay Vachaspati
If the observed dark energy is a cosmological constant, the canonical state of the universe is de Sitter spacetime. In such a spacetime, quantum fluctuations that violate the null energy condition will create islands of matter that, if large enough, may resemble our observable universe. Phenomenological approaches to calculating density fluctuations yield a
Spin Density and Non-Collinear Magnetization in Frustrated Pyrochlore \tbti from Polarized Neutron Scattering
cond-mat.str-elArsen Gukasov, Huibo Cao, Isabelle Mirebeau, Pierre Bonville
We used a local susceptibility approach in extensive polarized neutron diffraction studies of the spin liquid \tbti. For a magnetic field applied along the [110] and [111] directions, we found that, at high temperature, all Tb moments are collinear and parallel to the field. With decreasing temperature, the Tb moments reorient from the field direction to the
Xinghua Deng, Robert V. Moody
Examples of distinct weighted model sets with equal 2, 3, 4, 5-point correlations are given.
Syukyo G. Ryu, Katsuji Koyama, Masayoshi Nobukawa, Ryosuke Fukuoka
We present a new methodology to derive the positions of the Sgr B molecular clouds (MCs) along the line of sight, as an application study of the Galactic center diffuse X-rays (GCDX). The GCDX is composed of hot plasma emission of about 7 keV and 1 keV temperatures, and non-thermal continuum emission including the 6.4 keV line from neutral irons. The former,
Andrey R. Kolovsky, Edgar A. Gómez, Hans Jürgen Korsch
The dynamics of a (quasi)one-dimensional interacting atomic Bose-Einstein condensate in a tilted optical lattice is studied in a discrete mean-field approximation, i.e., in terms of the discrete nonlinear Schrödinger equation. If the static field is varied the system shows a plethora of dynamical phenomena. In the strong field limit we demonstrate the existe
Zinaida A. Lykova
We investigate the higher-dimensional amenability of tensor products $\A \ptp \B$ of Banach algebras $\A$ and $\B$. We prove that the weak bidimension $db_w$ of the tensor product $\A \ptp \B$ of Banach algebras $\A$ and $\B$ with bounded approximate identities satisfies \[ db_w \A \ptp \B = db_w \A + db_w \B. \] We show that it cannot be extended to arbitra
Anderson transitions : multifractal or non-multifractal statistics of the transmission as a function of the scattering geometry
cond-mat.dis-nnCecile Monthus, Thomas Garel
The scaling theory of Anderson localization is based on a global conductance $g_L$ that remains a random variable of order O(1) at criticality. One realization of such a conductance is the Landauer transmission for many transverse channels. On the other hand, the statistics of the one-channel Landauer transmission between two local probes is described by a m
J. Vranjes, S. Poedts
The solar coronal heating problem refers to the question why the temperature of the Sun's corona is more than two orders of magnitude higher than that of its surface. Almost 70 years after the discovery, this puzzle is still one of the major challenges in astrophysics. The current basic paradigm of coronal heating is unable to explain all the observation
Scintillator counters with WLS fiber/MPPC readout for the side muon range detector (SMRD)of the T2K experiment
physics.ins-detA. Izmaylov, S. Aoki, J. Blocki, J. Brinson
The T2K neutrino experiment at J-PARC uses a set of near detectors to measure the properties of an unoscillated neutrino beam and neutrino interaction cross-sections. One of the sub-detectors of the near-detector complex, the side muon range detector (SMRD), is described in the paper. The detector is designed to help measure the neutrino energy spectrum, to
Marek Rogatko, Agnieszka Szypłowska
We study the effect of extra dimensions on the process of massive Dirac fermion emission in the spacetime of (4+n)-dimensional black hole, by examining the Dirac operator in arbitrary spacetime dimension. We comment on both bulk and brane emission and find absorption cross section and luminosity of Hawking radiation in the low-energy approximation.
Masahiro Ogihara, Shigeru Ida
We have investigated planetary accretion from planetesimals in terrestrial planet regions inside the ice line around M dwarf stars through N-body simulations including tidal interactions with disk gas. Because of low luminosity of M dwarfs, habitable zones (HZs) are located in inner regions. In the close-in HZ, type-I migration and the orbital decay induced
Amin Aminzadeh Gohari, Venkat Anantharam
In this paper, we generalize the well known cut-set bound to the problem of lossy transmission of functions of arbitrarily correlated sources over a discrete memoryless multiterminal network.
Ning Lu, Zhenyu Li, Jinlong Yang
Two dimensional materials are important for electronics applications. A natural way for electronic structure engineering on two dimensional systems is on-plane chemical functionalization. Based on density functional theory, we study the electronic structures of fluorine substituted planar polysilane and graphane. We find that carbon and silicon present very
Jesus Romero-Valencia, Alexis G. Zamora
Given a canonical genus three curve $X=\{F=0\}$, we construct, emulating Mumford discussion for hyperelliptic curves, a set of equations for an affine open subset of the jacobian $JX$. We give explicit algorithms describing the law group in $JX$. Finally we introduce a related construction by means of an imbedding of the open set previously described in a Gr
Carsten Güttler, Maya Krause, Ralf J. Geretshauser, Roland Speith
In the recent years we have performed various experiments on the collision dynamics of highly porous dust aggregates and although we now have a comprehensive picture of the micromechanics of those aggregates, the macroscopic understanding is still lacking. We are therefore developing a mechanical model to describe dust aggregate collisions with macroscopic p
Eugene Ostrovsky, Leonid Sirota
In this article we investigate the so-called Bilateral Small Lebesgue Spaces: prove that they are associated to the Grand Lebesgue spaces, calculate its fundamental functions and Boyd's indices find its dual spaces etc.
Gulsheen Ahuja, Manmohan Gupta, Monika Randhawa, Rohit Verma
Considering Dirac neutrinos and Fritzsch-like texture 6 zero and 5 zero mass matrices, detailed predictions for cases pertaining to normal/inverted hierarchy as well as degenerate scenario of neutrino masses have been carried out. All the cases considered here pertaining to inverted hierarchy and degenerate scenario of neutrino masses are ruled out by the ex
Spin current and spin accumulation near a Josephson junction between a singlet and triplet superconductor
cond-mat.supr-conChi-Ken Lu, Sungkit Yip
We consider a Josephson junction with an arbitrary transmission coefficient $\mathcal{D}$ between a singlet and a triplet superconductor with the latter order parameter characterized by a d-vector of the form ($k_x\hat{y}-k_y\hat{x}$). Various quantities such as the tunnelling current, spin accumulation, and spin current are calculated via the quasiclassical
Fei Li, Zhi Zhang
We consider online scheduling weighted packets with time constraints over a fading channel. Packets arrive at the transmitter in an online manner. Each packet has a value and a deadline by which it should be sent. The fade state of the channel determines the throughput obtained per unit of time and the channel's quality may change over time. In this pape
Tunneling and delocalization in hydrogen bonded systems: a study in position and momentum space
cond-mat.stat-mechJoseph A. Morrone, Lin Lin, Roberto Car
Novel experimental and computational studies have uncovered the proton momentum distribution in hydrogen bonded systems. In this work, we utilize recently developed open path integral Car-Parrinello molecular dynamics methodology in order to study the momentum distribution in phases of high pressure ice. Some of these phases exhibit symmetric hydrogen bonds
Alberto Piatti, Marco Zaffalon, Fabio Trojani, Marcus Hutter
In this paper, we consider the coherent theory of (epistemic) uncertainty of Walley, in which beliefs are represented through sets of probability distributions, and we focus on the problem of modeling prior ignorance about a categorical random variable. In this setting, it is a known result that a state of prior ignorance is not compatible with learning. To
Cenk M. Yetis, Syed A. Jafar, Ahmet H. Kayran
The degrees of freedom of MIMO interference networks with constant channel coefficients are not known in general. Determining the feasibility of a linear interference alignment solution is a key step toward solving this open problem. Our approach in this paper is to view the alignment problem as a system of bilinear equations and determine its solvability by
Paul Tune, Sibiraj Bhaskaran Pillai, Stephen Hanly
We analyze the asymptotic performance of sparse signal recovery from noisy measurements. In particular, we generalize some of the existing results for the Gaussian case to subgaussian and other ensembles. An achievable result is presented for the linear sparsity regime. A converse on the number of required measurements in the sub-linear regime is also presen
A scalable quantum computer with an ultranarrow optical transition of ultracold neutral atoms in an optical lattice
quant-phK. Shibata, S. Kato, A. Yamaguchi, S. Uetake
We propose a new quantum-computing scheme using ultracold neutral ytterbium atoms in an optical lattice. The nuclear Zeeman sublevels define a qubit. This choice avoids the natural phase evolution due to the magnetic dipole interaction between qubits. The Zeeman sublevels with large magnetic moments in the long-lived metastable state are also exploited to ad
Anthony Zuppero, Thomas J. Dolan
A particular type of surface chemical reaction resulted in direct charge ejection. Several different experimental observations strongly support the hypothesis that nearly all of the molecular kinetic energy of a highly excited vibrating molecule was transferred to the kinetic energy of a single electron in a conducting lattice, leaving the molecule in nearly
Multiscale limit for finite-gap Sine-Gordon Solutions and Calculation of Topological Charge using Theta-functional Formulae
math-phP. G. Grinevich, K. V. Kaipa
In this paper, we introduce the so-called multiscale limit for spectral curves, associated with real finite-gap Sine-Gordon solutions. This technique allows to solve the old problem of calculating the density of topological charge for real finite-gap Sine-Gordon solutions directly from the $θ$-functional formulas.
Mingshang Hu, Shige Peng
We give a very simple and elementary proof of the existence of a weakly compact family of probability measures $\{P_θ:θ\in Θ\}$ to represent an important sublinear expectation--G-expectation $\mathbb{E}[\cdot]$. We also give a concrete approximation of a bounded continuous function $X(ω)$ by an increasing sequence of cylinder functions $L_{ip}(Ω)$ in order t
Guillermo Morales-Luna
Given a real objective function defined over the symmetric group, a direct local-search algorithm is proposed, and its complexity is estimated. In particular for an $n$-dimensional unit vector we are interested in the permutation isometry that acts on this vector by mapping it into a cone of a given angle.
The Joint Milli-Arcsecond Pathfinder Survey (JMAPS): Mission Overview and Attitude Sensing Applications
astro-ph.SRBryan N. Dorland, Rachel P. Dudik, Zachary Dugan, Gregory S. Hen- nessy
The Joint Milliarcsecond Pathfinder Survey (JMAPS) is a Department of Navy bright star astrometric all-sky survey scheduled for launch in the 2012 timeframe. Mission objectives include a complete update of star positions for the 2015 epoch to accuracy levels of 1 milliarcsecond (5 nano-radians) for bright stars, as well as demonstration of 10 milliarcsecond
I. Anapolitanos, I. M. Sigal
In the mean-field regime, we prove convergence (with explicit bounds) of the many-body von Neumann dynamics with bounded interactions to the Hartree-von Neumann dynamics.
András Z. Salamon, Vashti Galpin
We use activity networks (task graphs) to model parallel programs and consider series-parallel extensions of these networks. Our motivation is two-fold: the benefits of series-parallel activity networks and the modelling of programming constructs, such as those imposed by current parallel computing environments. Series-parallelisation adds precedence constra
E. Tolstoy, V. Hill, M. Tosi
Within the Local Universe galaxies can be studied in great detail star by star, and here we review the results of quantitative studies in nearby dwarf galaxies. The Color-Magnitude Diagram synthesis method is well established as the most accurate way to determine star formation history of galaxies back to the earliest times. This approach received a large bo
Carlos F. Sopuerta, Nicolas Yunes
[abridged] Chern-Simons (CS) modified gravity is a 4D effective theory that descends both from string theory and loop quantum gravity, and that corrects the Einstein-Hilbert action by adding the product of a scalar field and the parity-violating, Pontryagin density. In this theory, the gravitational field of spinning black holes is described by a modified Ke
M. Haltmeier, O. Scherzer, G. Zangerl
Fourier reconstruction algorithms significantly outperform conventional back-projection algorithms in terms of computation time. In photoacoustic imaging, these methods require interpolation in the Fourier space domain, which creates artifacts in reconstructed images. We propose a novel reconstruction algorithm that applies the one-dimensional nonuniform fas
Alexander E. Holroyd, James Propp
The rotor walk is a derandomized version of the random walk on a graph. On successive visits to any given vertex, the walker is routed to each of the neighboring vertices in some fixed cyclic order, rather than to a random sequence of neighbors. The concept generalizes naturally to Markov chains on a countable state space. Subject to general conditions, we p
A. Ceresole, S. Ferrara, A. Gnecchi, A. Marrani
We examine few simple extremal black hole configurations of N=8, d=4 supergravity. We first elucidate the relation between the BPS Reissner-Nordstrom black hole and the non-BPS Kaluza-Klein dyonic black hole. Their classical entropy, given by the Bekenstein-Hawking formula, can be reproduced via the attractor mechanism by suitable choices of symplectic frame
Genoveva Micheva, Erik Zackrisson, Göran Östlin, Nils Bergvall
Previous studies of the host galaxy of Haro 11 have suggested an extreme red color of V-K=4.2+-0.8 which cannot be reconciled with any normal stellar population of reasonable metallicity. We present the deepest V and K band data to date of the blue compact galaxy (BCG) Haro 11 and derive a new V-K color for the host. Our new data suggest a much more modest v
L. Armus, J. M. Mazzarella, A. S. Evans, J. A. Surace
The Great Observatories All-sky LIRG Survey (GOALS) combines data from NASA's Spitzer, Chandra, Hubble and GALEX observatories, together with ground-based data into a comprehensive imaging and spectroscopic survey of over 200 low redshift Luminous Infrared Galaxies (LIRGs). The LIRGs are a complete subset of the IRAS Revised Bright Galaxy Sample (RBGS).
Mehdi Kargarian
In this work the topological order at finite temperature in two-dimensional color code is studied. The topological entropy is used to measure the behavior of the topological order. Topological order in color code arises from the colored string-net structures. By imposing the hard constrained limit the exact solution of the entanglement entropy becomes possib
Giulio Chiribella, Giacomo M. D'Ariano, Paolo Perinotti
We present a framework to treat quantum networks and all possible transformations thereof, including as special cases all possible manipulations of quantum states, measurements, and channels, such as, e.g., cloning, discrimination, estimation, and tomography. Our framework is based on the concepts of quantum comb-which describes all transformations achievabl
Lemaitre-Tolman-Bondi cosmological models, smoothness, and positivity of the central deceleration parameter
astro-ph.COR. Ali Vanderveld, Eanna E. Flanagan, Ira Wasserman
We argued in a previous paper [R. A. Vanderveld et al. 2006, arXiv:astro-ph/0602476] that negative deceleration parameters at the center of symmetry in Lemaitre-Tolman-Bondi cosmological models can only occur if the model is not smooth at the origin. Here we demonstrate explicitly the connection between non-smoothness and the failure of positivity theorems f
S Deser
Canonical analysis of a recently proposed [1] linear+quadratic curvature gravity model in D=3 displays its pure fourth derivative quadratic branch as a ghost-free (massless) excitation. Hence it both negates an old no-go theorem and is power-counting UV finite. It is also conformal-invariant, so the metric is underdetermined. While the 2-term branch is also
Brant C. Jones
We give an explicit nonrecursive complete matching for the Hasse diagram of the strong Bruhat order of any interval in any Coxeter group. This yields a new derivation of the Mobius function, recovering a classical result due to Verma.
Joy Christian
An elementary topological error in Bell's representation of the EPR elements of reality is identified. Once recognized, it leads to a topologically correct local-realistic framework that provides exact, deterministic, and local underpinning of at least the Bell, GHZ-3, GHZ-4, and Hardy states. The correlations exhibited by these states are shown to be ex
Radu Balan, Pete Casazza, Zeph Landau
Redundancy is the qualitative property which makes Hilbert space frames so useful in practice. However, developing a meaningful quantitative notion of redundancy for infinite frames has proven elusive. Though quantitative candidates for redundancy exist, the main open problem is whether a frame with redundancy greater than one contains a subframe with redund
Low-temperature thermal conductivity of BaFe2As2: Parent compound of iron-arsenide superconductors
cond-mat.str-elN. Kurita, F. Ronning, C. F. Miclea, E. D. Bauer
We report low-temperature thermal conductivity down to 40 mK of the antiferromagnet BaFe$_2$As$_{2}$, which is the parent compound of recently discovered iron-based superconductors. In the investigated temperature range below 4 K, the thermal conductivity $κ$ is well described by the expression $κ$ = $aT$ + $bT^{2.22}$. We attribute the ``$aT$''-term
P. Yao, S. Hughes
We introduce a photonic crystal waveguide-cavity system for controlling single photon cavity-QED processes. Exploiting Bloch mode analysis, and medium-dependent Green function techniques, we demonstrate that the propagation of single photons can be accurately described analytically, for integrated periodic waveguides with little more than four unit cells, in
Davide Gaiotto, Juan Maldacena
We study the gauge/gravity duality for theories with four dimensional ${\cal N}=2$ supersymmetries. We consider the large class of generalized quiver field theories constructed recently by one of us (D.G.). These field theories can also be viewed as the IR limit of M5 branes wrapping a Riemann surface with punctures. We give a prescription for constructing t
Jack S. Calcut, Robert E. Gompf, John D. McCarthy
In classical covering space theory, a covering map induces an injection of fundamental groups. This paper reveals a dual property for certain quotient maps having connected fibers, with applications to orbit spaces of vector fields and leaf spaces in general.
Troels Harmark
We introduce the domain structure for stationary black hole space-times. Given a set of commuting Killing vector fields of the space-time the domain structure lives on the submanifold where at least one of the Killing vector fields have zero norm. Depending on which Killing vector field has zero norm the submanifold is naturally divided into domains. A domai
Thomas P. Sotiriou, Matt Visser, Silke Weinfurtner
Horava's "Lifschitz point gravity" has many desirable features, but in its original incarnation one is forced to accept a non-zero cosmological constant of the wrong sign to be compatible with observation. We develop an extension of Horava's model that abandons "detailed balance", and in 3+1 dimensions exhibit all five marginal (renor
Vyacheslav Boyko, Jiri Patera, Roman Popovych
A purely algebraic algorithm for computation of invariants (generalized Casimir operators) of Lie algebras by means of moving frames is discussed. Results on the application of the method to computation of invariants of low-dimensional Lie algebras and series of solvable Lie algebras restricted only by a required structure of the nilradical are reviewed.
M. V. Chekhova, G. Kh. Kitaeva, O. A. Shumilkina, I. P. Degiovanni
We show that broadband biphoton wavepackets produced via Spontaneous Parametric Down-Conversion (SPDC) in crystals with linearly aperiodic poling can be easily compressed in time using the effect of group-velocity dispersion in optical fibres. This result could foster important developments in quantum metrology and lithography.
Impurity effect as a probe for order parameter symmetry in iron-based superconductors
cond-mat.supr-conTao Zhou, Xiang Hu, Jian-Xin Zhu, C. S. Ting
The pointlike impurity scattering is studied for a superconductor with different pairing symmetries based on a minimal two band model proposed by S. Raghu $et$ $al.$ [Phys. Rev. B {\bf 77}, R220503 (2008)], and the self-consistent Bogoliubov-de Gennes equations. Two intra-gap resonance peaks are found at or near the nonmagnetic impurity site for a typical $s
Michael T. Goodrich
We study the degree to which a character string, $Q$, leaks details about itself any time it engages in comparison protocols with a strings provided by a querier, Bob, even if those protocols are cryptographically guaranteed to produce no additional information other than the scores that assess the degree to which $Q$ matches strings offered by Bob. We show
Duiliu-Emanuel Diaconescu
ADHM invariants are equivariant virtual invariants of moduli spaces of twisted cyclic representations of the ADHM quiver in the abelian category of coherent sheaves of a smooth complex projective curve X. The goal of the present paper is to present a generalization of this construction employing a more general stability condition which depends on a real para
J. Seely, A. Daniel, D. Gaskell, J. Arrington
New Jefferson Lab data are presented on the nuclear dependence of the inclusive cross section from 2H, 3He, 4He, 9Be and 12C for 0.3<x<0.9, Q^2 approximately 3-6 GeV^2. These data represent the first measurement of the EMC effect for 3He at large x and a significant improvement for 4He. The data do not support previous A-dependent or density-dependent fits t
Andrea Campoleoni, Dario Francia, Jihad Mourad, Augusto Sagnotti
This paper is a sequel of arXiv:0810.4350 [hep-th], and is also devoted to the local "metric-like" unconstrained Lagrangians and field equations for higher-spin fields of mixed symmetry in flat space. Here we complete the previous constrained on-shell formulation of Labastida for Fermi fields, deriving the corresponding constrained Lagrangians both v
Shot noise and conductivity at high bias in bilayer graphene: Signatures of electron-optical phonon coupling
cond-mat.mes-hallA. Fay, R. Danneau, J. K. Viljas, F. Wu
We have studied electronic conductivity and shot noise of bilayer graphene (BLG) sheets at high bias voltages and low bath temperature $T_0=4.2$ K. As a function of bias, we find initially an increase of the differential conductivity, which we attribute to self-heating. At higher bias, the conductivity saturates and even decreases due to backscattering from
M. Veneziani, A. Amblard, A. Cooray, F. Piacentini
The Sunyaev-Zel'dovich (SZ) effect is the inverse Compton-scattering of cosmic microwave background (CMB) photons by hot electrons in the intervening gas throughout the universe. The effect has a distinct spectral signature that allows its separation from other signals in multifrequency CMB datasets. Using CMB anisotropies measured at three frequencies b
Signatures of the super fluid-insulator phase transition in laser driven dissipative nonlinear cavity arrays
cond-mat.str-elA. Tomadin, V. Giovannetti, R. Fazio, D. Gerace
We analyze the non-equilibrium dynamics of a gas of interacting photons in an array of coupled dissipative nonlinear cavities driven by a pulsed external coherent field. Using a mean-field approach, we show that the system exhibits a phase transition from a Mott-insulator-like to a superfluid regime. For a given single-photon nonlinearity, the critical value
F. Cianfrani, G. Montani
We analyze the phase space of gravity non-minimally coupled to a scalar field in a generic local Lorentz frame. We reduce the set of constraints to a first-class one by fixing a specific hypersurfaces in the phase space. The main issue of our analysis is to extend the features of the vacuum case to the presence of scalar matter by recovering the emergence of
Sara M. Petty, Duilia F. de Mello, John S. Gallagher, Jonathan P. Gardner
The rest-frame far-ultraviolet (FUV) morphologies of 8 nearby interacting and starburst galaxies (Arp 269, M 82, Mrk 8, NGC 520, NGC 1068, NGC 3079, NGC 3310, NGC 7673) are compared with 54 galaxies at z ~ 1.5 and 46 galaxies at z ~ 4 observed in the GOODS-ACS field. The nearby sample is artificially redshifted to z ~ 1.5 and 4. We compare the simulated gala
Paweł Sieczka, Janusz A. Hołyst
We present a simple model of firm rating evolution. We consider two sources of defaults: individual dynamics of economic development and Potts-like interactions between firms. We show that such a defined model leads to phase transition, which results in collective defaults. The existence of the collective phase depends on the mean interaction strength. For s
David Orden, Pedro Ramos, Gelasio Salazar
Let $S$ be a set of $r$ red points and $b=r+2d$ blue points in general position in the plane, with $d\geq 0$. A line $\ell$ determined by them is said to be balanced if in each open half-plane bounded by $\ell$ the difference between the number of red points and blue points is $d$. We show that every set $S$ as above has at least $r$ balanced lines. The main
Michal Dobrski
It is shown how Seiberg-Witten equations can be obtained by means of Fedosov deformation quantization of endomorphism bundle and the corresponding theory of equivalences of star products. In such setting, Seiberg-Witten map can be iteratively computed for arbitrary gauge group up to any given degree with recursive methods of Fedosov construction. Presented a
Florian Enescu
We study the relationship between the Frobenius stability of an Artinian module over an F-injective ring and its stable part.
K. A. Bugaev, V. K. Petrov, G. M. Zinovjev
We discuss a new way to develop the exactly solvable model of the QCD critical endpoint by matching the deconfinement phase transition line for the system of quark-gluon bags with the line of their vanishing surface tension coefficient. In contrast to all previous findings in such models the deconfined phase is defined not by an essential singularity of the
Yuko Urakawa, Takahiro Tanaka
We propose one way to regularize the fluctuations generated during inflation, whose infrared (IR) corrections diverge logarithmically. In the case of a single field inflation model, recently, we proposed one solution to the IR divergence problem. There, we introduced new perturbative variables which better mimic actual observable fluctuations, and proved the
Mark Durkee
This short note shows that many of the results derived by Pravda et al (Class. Quant. Grav. 24 4407-4428) for higher-dimensional Type D Einstein spacetimes can be generalized to all Einstein spacetimes admitting a multiple WAND; the main new result being the extension to include the Type II case. Examples of Type D Einstein spacetimes admitting non-geodesic
Daniel de Florian
We compute the next-to-leading order QCD corrections to the spin-independent and spin-dependent cross-sections for the production of a single-hadron accompanied by an opposite jet in hadronic collisions. This process is being studied experimentally at RHIC, providing a new tool to unveil the polarized gluon distribution Delta g. We perform a detailed analysi
Mustafa Sarisaman
We study the pseudoduality transformation in supersymmetric sigma models. We generalize the classical construction of pseudoduality transformation to supersymmetric case. We perform this both by component expansion method on manifold M and by orthonormal coframe method on manifold SO(M). The component expansion method yields the result that pseudoduality tra
Maresuke Shiraishi, Kazuhide Ichikawa, Kiyotomo Ichiki, Naoshi Sugiyama
In this paper, we put constraints on neutrino properties such as mass $m_ν$ and degeneracy parameters $ξ_i$ from WMAP5 data and light element abundances by using a Markov chain Monte Carlo (MCMC) approach. In order to take consistently into account the effects of the degeneracy parameters, we run the Big Bang Nucleosynthesis code for each value of $ξ_i$ and
Michael Motsch, Martin Zeppenfeld, Pepijn W. H. Pinkse, Gerhard Rempe
We demonstrate Purcell-like enhancement of Rayleigh scattering into a single optical mode of a Fabry-Perot resonator for several thermal atomic and molecular gases. The light is detuned by more than an octave, in this case by hundreds of nanometers, from any optical transition, making particle excitation and spontaneous emission negligible. The enhancement o
Mateusz Michalek
We consider two varieties associated to a web of quadrics W in the projective space of dimension 7. One is the base locus and the second one is the double cover of the three dimensional projective space branched along the determinant surface of W. We show that small resolutions of these varieties are Calabi-Yau manifolds. We compute their Betti numbers and s
Ting Jia, Guoren Zhang, Zhi Zeng, H. Q. Lin
The magnetic properties of NaVO2 are investigated using full-potential linearized augmented plane wave method. We perform calculations for three structures. For the rhombohedral structure at 100 K, the t2g orbitals of V ions are split into upper a1g and lower e'g orbitals by a trigonal distortion of compression. For the monoclinic structure at 91.5 K, th
Constanze Roedig, Thomas Burkart, Oliver Elbracht, Felix Spanier
Context: Active Galactic Nuclei are highly variable emitters of electromagnetic waves from the radio to the gamma-ray regime. This variability may be periodic, which in turn could be the signature of a binary black hole. Systems of black holes are strong emitters of gravitational waves whose amplitude depends on the binary orbital parameters as the component
Observational tests of a two parameter power-law class modified gravity in Palatini formalism
astro-ph.COShant Baghram, M. Sadegh Movahed, Sohrab Rahvar
{\bf{CONTEXT}}: In this work we propose a modified gravity action $f(R)=(R^n-R^n_{0})^{1/n}$ with two free parameters of $n$ and $R_{0}$ and derive the dynamics of a universe for this action in the Palatini formalism. {\bf {AIM}}: We do a cosmological comparison of this model with observed data to find the best parameters of a model in a flat universe. {\bf{
Asymptotyczna teoria reprezentacji grup permutacji (Asymptotic representation theory of symmetric groups)
math.RTPiotr Sniady
This article (written in Polish) is aimed for a wide mathematical audience. It is intended as an introductory text concerning problems of the asymptotic theory of symmetric groups.
Bram Mesland
By introducing a notion of smooth connection for unbounded $KK$-cycles, we show that the Kasparov product of such cycles can be defined directly, by an algebraic formula. In order to achieve this it is necessary to develop a framework of smooth algebras and a notion of differentiable $C^{*}$-module. The theory of operator spaces provides the required tools.
Density profile, velocity anisotropy and line-of-sight external convergence of SLACS gravitational lenses
astro-ph.COAntonio C. C. Guimarães, Laerte Sodré
Data from 58 strong-lensing events surveyed by the Sloan Lens ACS Survey are used to estimate the projected galaxy mass inside their Einstein radii by two independent methods: stellar dynamics and strong gravitational lensing. We perform a joint analysis of these two estimates inside models with up to three degrees of freedom with respect to the lens density