Research archive
arXiv papers from April 2013
The most recent 100 records published that month. Open any paper for its original abstract, citation metadata, related research, and reading tools.
A. Stavrova
Let R be a connected noetherian commutative ring, and let G be a simply connected reductive group over R of isotropic rank ge 2. The elementary subgroup E(R) of G(R) is the subgroup generated by the R-points U_P^+(R) and U_P^-(R) of the unipotent radicals of two opposite parabolic subgroups P^+ and P^- of G. Assume that 2 is invertible in R if G is of type B
P. S. Bhupal Dev, Srubabati Goswami, Manimala Mitra, Werner Rodejohann
We re-analyze the compatibility of the claimed observation of neutrinoless double beta decay ($0\nu\beta\beta$) in $^{76}$Ge with the new limits on the half-life of $^{136}$Xe from EXO-200 and KamLAND-Zen. Including recent calculations of the nuclear matrix elements (NMEs), we show that while the claim in $^{76}$Ge is still compatible with the individual lim
Yi-Chao Li, Feng-Quan Wu, Xuelei Chen
Based on the new cosmic CMB temperature data from the Planck satellite, the 9 year polarization data from the WMAP, the BAO distance ratio data from the SDSS and 6dF surveys, we place a new constraint on the Brans-Dicke theory. We adopt a parametrization $\zeta=\ln(1+1/\omega})$, where the general relativity (GR) limit corresponds to $\zeta = 0$. We find no
- Spin polarization of Ru in superconducting Ba(Fe$_{0.795}$Ru$_{0.205}$)$_2$As$_2$ studied by x-ray resonant magnetic scatteringcond-mat.str-el
M. G. Kim, J. Soh, J. Lang, M. P. M. Dean
We have employed the x-ray resonant magnetic scattering (XRMS) technique at the Ru $L_2$ edge of the Ba(Fe$_{1-x}$Ru$_x$)$_2$As$_2$ ($x = 0.205$) superconductor. We show that pronounced resonance enhancements at the Ru $L_2$ edge are observed at the wave vector which is consistent with the antiferromagnetic propagation vector of the Fe in the undoped BaFe$_2
Holger F. Hofmann
Recently, weak measurements have attracted a lot of interest as an experimental method for the investigation of non-classical correlations between observables that cannot be measured jointly. Here, I explain how the complex valued statistics observed in weak measurements relate to the operator algebra of the conventional Hilbert space formalism and show that
Christophe Hohlweg, Jean-Philippe Préaux, Vivien Ripoll
The notion of limit roots of a Coxeter group W was recently introduced (see arXiv:1112.5415 and arXiv:1303.6710): they are the accumulation points of directions of roots of a root system for W. In the case where the root system lives in a Lorentzian space W admits a faithful representation as a discrete reflection group of isometries on a hyperbolic space; t
Kevin S. Xu, Mark Kliger, Yilun Chen, Peter J. Woolf
To date, most studies on spam have focused only on the spamming phase of the spam cycle and have ignored the harvesting phase, which consists of the mass acquisition of email addresses. It has been observed that spammers conceal their identity to a lesser degree in the harvesting phase, so it may be possible to gain new insights into spammers' behavior by st
- A multi-wavelength view of cooling vs. AGN heating in the X-ray luminous cool-core of Abell 3581astro-ph.CO
R. E. A. Canning, M. Sun, J. S. Sanders, T. E. Clarke
We report the results of a multi-wavelength study of the nearby galaxy group, Abell 3581 (z=0.0218). This system hosts the most luminous cool core of any nearby group and exhibits active radio mode feedback from the super-massive black hole in its brightest group galaxy, IC 4374. The brightest galaxy has suffered multiple active galactic nucleus outbursts, b
Bertrand Deroin, Romain Dujardin
Let (\rho_\la)_{\la\in \La} be a holomorphic family of representations of a surface group \pi_1(S) into PSL(2,C), where S is a topological (possibly punctured) surface with negative Euler characteristic. Given a structure of Riemann surface of finite type on S we construct a bifurcation current on the parameter space \La, that is a (1,1) positive closed curr
Jeff Greensite, Kurt Langfeld
We calculate the effective Polyakov line action corresponding to SU(2) lattice gauge theory on a 16^3 X 4 lattice via the "relative weights" method. We consider a variety of lattice couplings, ranging from beta=1.2 in the strong-coupling domain, to beta=2.3 at the deconfinement transition, in order to study how the effective action evolves with beta. Compari
Ji Liu, Lei Yuan, Jieping Ye
We consider the following signal recovery problem: given a measurement matrix $\Phi\in \mathbb{R}^{n\times p}$ and a noisy observation vector $c\in \mathbb{R}^{n}$ constructed from $c = \Phi\theta^* + \epsilon$ where $\epsilon\in \mathbb{R}^{n}$ is the noise vector whose entries follow i.i.d. centered sub-Gaussian distribution, how to recover the signal $\th
Bingyuan Liu
In this paper, finite type domains with hyperbolic orbit accumulation points are studied. We prove, in case of $\mathbb{C}^2$, it has to be a (global) pseudoconvex domain, after an assumption of boundary regularity. Moreover, one of the applications will realize the classification of domains within this class, precisely the domain is biholomorphic to one of
- Strict comparison of projections and positive combinations of projections in certain multiplier algebrasmath.OA
Victor Kaftal, P. W. Ng, Shuang Zhang
In this paper we investigate whether positive elements in the multiplier algebras of certain finite C*-algebras can be written as finite linear combinations of projections with positive coefficients (PCP). Our focus is on the category of underlying C*-algebras that are separable, simple, with real rank zero, stable rank one, finitely many extreme traces, and
Alon E. Faraggi
The equivalence postulate approach to quantum mechanics entails a derivation of quantum mechanics from a fundamental geometrical principle. Underlying the formalism there exists a basic cocycle condition, which is invariant under D-dimensional finite Mobius transformations. The invariance of the cocycle condition under finite Mobius transformations implies t
Mariusz Mirek
Let $\mathbf{P}$ denote the set of prime numbers and, for an appropriate function $h$, define a set $\mathbf{P}_{h}=\{p\in\mathbf{P}: \exists_{n\in\mathbb{N}}\ p=\lfloor h(n)\rfloor\}$. The aim of this paper is to show that every subset of $\mathbf{P}_{h}$ having positive relative upper density contains a nontrivial three-term arithmetic progression. In part
S. Torres-Flores, R. Barbá, J. Maíz Apellániz, M. Rubio
We present high-quality VLT-FLAMES optical spectroscopy of the nebular gas in the giant star-forming region 30 Doradus. In this paper, the first of a series, we introduce our observations and discuss the main kinematic features of 30 Dor, as revealed by the spectroscopy of the ionized gas in the region. The primary data set consists of regular grid of nebula
Tomislav Stankovski, Andrea Duggento, Peter V. E. McClintock, Aneta Stefanovska
In view of the current availability and variety of measured data, there is an increasing demand for powerful signal processing tools that can cope successfully with the associated problems that often arise when data are being analysed. In practice many of the data-generating systems are not only time-variable, but also influenced by neighbouring systems and
Lorenzo Giada, Claudio Nordio
In this note we show how to replicate a stylized CDS with a repurchase agreement and an asset swap. The latter must be designed in such a way that, on default of the issuer, it is terminated with a zero close-out amount. This break clause can be priced using the well known unilateral credit/debit valuation adjustment formulas.
M. H. Mohammady
A promising platform for quantum information processing is that of silicon impurities, where the quantum states are manipulated by magnetic resonance. Such systems, in abstraction, can be considered as a nucleus of arbitrary spin coupled to an electron of spin one-half via an isotropic hyperfine interaction. We therefore refer to them as "nuclear-electronic
Hailong Wang, Luis A. Zepeda-Ruiz, George H. Gilmer, Moneesh Upmanyu
Vapor-liquid-solid (VLS) route and its variants are routinely used for scalable synthesis of semiconducting nanowires yet the fundamental growth processes remain unknown. Here, we employ atomic-scale computations based on model potentials to study the stability and growth of gold-catalyzed silicon nanowires (SiNWs). Equilibrium studies uncover segregation at
Christian Y. Cardall, Eirik Endeve, Anthony Mezzacappa
We present a new derivation of the conservative form of the general relativistic Boltzmann equation and specialize it to the 3+1 metric. The resulting transport equation is intended for use in simulations involving numerical relativity, particularly in the absence of spherical symmetry. The independent variables are lab frame coordinate basis spacetime posit
Axel D. Dente, Carlos S. Bederián, Pablo R. Zangara, Horacio M. Pastawski
The resolution of dynamics in out of equilibrium quantum spin systems lies at the heart of fundamental questions among Quantum Information Processing, Statistical Mechanics and Nano-Technologies. Efficient computational simulations of interacting many-spin systems are extremely valuable tools for tackling such questions. Here, we use the Trotter-Suzuki (TS)
Karim Belabas, Eduardo Friedman
Assuming the Generalized Riemann Hypothesis, Bach has shown that one can calculate the residue of the Dedekind zeta function of a number field K by a clever use of the splitting of primes p < X, with an error asymptotically bounded by 8.33 log D_K/(\sqrt{X}\log X), where D_K is the absolute value of the discriminant of K. Guided by Weil's explicit formula an
- Regret Minimization in Non-Zero-Sum Games with Applications to Building Champion Multiplayer Computer Poker Agentscs.GT
Richard Gibson
In two-player zero-sum games, if both players minimize their average external regret, then the average of the strategy profiles converges to a Nash equilibrium. For n-player general-sum games, however, theoretical guarantees for regret minimization are less understood. Nonetheless, Counterfactual Regret Minimization (CFR), a popular regret minimization algor
- Vanadium dioxide as a natural disordered metamaterial: perfect thermal emission and large broadband negative differential thermal emittancephysics.optics
Mikhail A. Kats, Romain Blanchard, Shuyan Zhang, Patrice Genevet
We experimentally demonstrate that a thin (~150 nm) film of vanadium dioxide (VO2) deposited on sapphire has an anomalous thermal emittance profile when heated, which arises due to the optical interaction between the film and the substrate when the VO2 is at an intermediate state of its insulator-metal transition (IMT). Within the IMT region, the VO2 film co
Mario Blaum
A construction of Partial Maximum Distance Separable (PMDS) and Sector-Disk (SD) codes extending RAID 5 with two extra parities is given, solving an open problem. Previous constructions relied on computer searches, while our constructions provide a theoretical solution to the problem.
K. K. Bardhan, D. Talukdar, U. N. Nandi, C. D. Mukherjee
The effect of an electric field on conduction in a disordered system is an old but largely unsolved problem. Experiments cover an wide variety of systems - amorphous/doped semiconductors, conducting polymers, organic crystals, manganites, composites, metallic alloys, double perovskites - ranging from strongly localized systems to weakly localized ones, from
L. V. Zadorozhna, B. I. Hnatyk, Yu. A. Sitenko
Cosmic strings are topological defects which can be formed as a result of phase transitions with a spontaneous symmetry breaking in the early Universe. The possibility of the generation of a magnetic field around a cosmic string on the Grand Unification energy scale (GUT scale) in the early Universe immediately after the termination of the deconfinement-conf
Schuyler D. Van Dyk
The Type IIn supernovae (SNe IIn) have been found to be associated with significant amounts of dust. These core-collapse events are generally expected to be the final stage in the evolution of highly-massive stars, either while in an extreme red supergiant phase or during a luminous blue variable phase. Both evolutionary scenarios involve substantial pre-sup
K. P. Zybin, V. A Sirota
The appearance of vortex filaments, the power-law dependence of velocity and vorticity correlators and their multiscaling behavior are derived from the Navier-Stokes equation. This is possible due to interpretation of the Navier-Stokes equation as an equation with multiplicative noise, and remarkable properties of random matrix products.
- Comments on two papers by Galliano Valent, concerning integrable Hamiltonian systems admitting quartic and cubic integralsnlin.SI
Hamad Yehia
In this note we comment on two recently published papers by G. Valent: The 1st is the preprint "On a Class of Integrable Systems with a quartic First Integral, arXiv:1304.5859. April 22, (2013)". We show that the two integrable Hamiltonian systems introduced in this reprint as original results are not new. They are special cases of two systems introduced by
Tepper L Gill
In this note we show that, if $\mcB$ is separable Banach space, then there is a biorthogonal system $\{x_n, x_n^*\}$ such that, the closed linear span of $\{x_n\},\bar{\left\langle {\{x_n\}}\right\rangle}=\mcB$ and $\left\| {x_n} \right\|\left\| {x_n^*} \right\| = 1$ for all $n$.
Christian G. Boehmer, Francisco S. N. Lobo, Nicola Tamanini
Hybrid metric-Palatini gravity is a recent and novel approach to modified theories of gravity, which consists of adding to the metric Einstein-Hilbert Lagrangian an f(R) term constructed a la Palatini. It was shown that the theory passes local tests even if the scalar field is very light, and thus implies the existence of a long-range scalar field, which is
Nathan Ilten, Hendrik Süß
Let X be a T-variety, where T is an algebraic torus. We describe a fully faithful functor from the category of T-equivariant vector bundles on X to a certain category of filtered vector bundles on a suitable quotient of X by T. We show that if X is factorial, this functor gives an equivalence of categories. This generalizes Klyachko's description of equivari
- Phenomenological Study of the Interplay between IR-Improved DGLAP-CS Theory and the Precision of an NLO ME Matched Parton Shower MChep-ph
S. K. Majhi, A. Mukhopadhyay, B. F. L. Ward, S. A. Yost
We present a phenomenological study of the current status of the application of our approach of {\it exact} amplitude-based resummation in quantum field theory to precision QCD calculations, by realistic MC event generator methods, as needed for precision LHC physics. We discuss recent results as they relate to the interplay of the attendant IR-Improved DGLA
J. Vandenbroucke, B. Humensky, J. Holder, R. A. Ong
Cosmic electrons, positrons, protons, and antiprotons carry essential information about both astrophysical processes and fundamental physics. Charged particles provide signatures of dark matter annihilation or decay, \emph{in situ} in the universe, that are complementary to the other messengers of indirect dark matter detection, gamma rays and neutrinos. We
- Dark matter coupling to electroweak gauge and Higgs bosons: an effective field theory approachhep-ph
Jing-Yuan Chen, Edward W. Kolb, Lian-Tao Wang
If dark matter is a new species of particle produced in the early universe as a cold thermal relic (a weakly-interacting massive particle-WIMP), its present abundance, its scattering with matter in direct-detection experiments, its present-day annihilation signature in indirect-detection experiments, and its production and detection at colliders, depend cruc
Firas A. Jassim
The standard JPEG format is almost the optimum format in image compression. The compression ratio in JPEG sometimes reaches 30:1. The compression ratio of JPEG could be increased by embedding the Five Modulus Method (FMM) into the JPEG algorithm. The novel algorithm gives twice the time as the standard JPEG algorithm or more. The novel algorithm was called F
S. V. Dordevic, D. N. Basov, C. C. Homes
Universal scaling relations are of tremendous importance in science, as they reveal fundamental laws of nature. Several such scaling relations have recently been proposed for superconductors; however, they are not really universal in the sense that some important families of superconductors appear to fail the scaling relations, or obey the scaling with diffe
Jakob Palmkvist
We introduce an infinite-dimensional Lie superalgebra which is an extension of the U-duality Lie algebra of maximal supergravity in D dimensions, for D between 3 and 7. The level decomposition with respect to the U-duality Lie algebra gives exactly the tensor hierarchy of representations that arises in gauge deformations of the theory described by an embeddi
Elizabeth E. Jenkins, Aneesh V. Manohar, Michael Trott
The principle of minimal coupling has been used in the study of Higgs boson interactions to argue that certain higher dimensional operators in the low-energy effective theory generalization of the Standard Model are suppressed by loop factors, and thus smaller than others. It also has been extensively used to analyze beyond-the-standard-model theories. We sh
M. H. M. Morais, F. Namouni
We continue the investigation of the dynamics of retrograde resonances initiated in Morais & Giuppone (2012). After deriving a procedure to deduce the retrograde resonance terms from the standard expansion of the three-dimensional disturbing function, we concentrate on the planar problem and construct surfaces of section that explore phase-space in the vicin
Balaji Lakshminarayanan, Yee Whye Teh
A popular approach for large scale data annotation tasks is crowdsourcing, wherein each data point is labeled by multiple noisy annotators. We consider the problem of inferring ground truth from noisy ordinal labels obtained from multiple annotators of varying and unknown expertise levels. Annotation models for ordinal data have been proposed mostly as exten
- Framework for maximum likelihood analysis of neutron beta decay observables to resolve the limits of the V-A lawhep-ph
S. Gardner, B. Plaster
We assess the ability of future neutron beta decay measurements of up to O(10^{-4}) precision to falsify the standard model, particularly the V-A law, and to identify the dynamics beyond it. To do this, we employ a maximum likelihood statistical framework which incorporates both experimental and theoretical uncertainties. Using illustrative combined global f
Constantin Candu, Carl Vollenweider
The main objective of this work is to construct and classify the most general classical and quantum $\mathcal{N}=1$ $\mathcal{W}_\infty$-algebras generated by the same spins as the singlet algebra of $N$ fermions and $N$ bosons in the vector representation of $O(N)$ in the $N\to\infty$ limit. This type of algebras appears in a recent $\mathcal{N}=1$ version
William E. Lucas, Ian A. Bonnell, Melvyn B. Davies, Ken Rice
We follow the near radial infall of a prolate cloud onto a 4 x 10^6 Msun supermassive black hole in the Galactic Centre using smoothed particle hydrodynamics (SPH). We show that a prolate cloud oriented perpendicular to its orbital plane naturally produces a spread in angular momenta in the gas which can translate into misaligned discs as is seen in the youn
Grigory Bednik, Oriol Pujolas, Sergey Sibiryakov
We explore the phenomenon of emergent Lorentz invariance in strongly coupled theories. The strong dynamics is handled using the gauge/gravity correspondence. We analyze how the renormalization group flow towards Lorentz invariance is reflected in the two-point functions of local operators and in the dispersion relations of the bound states. The deviations of
Cornelius Rampf, Gerasimos Rigopoulos
We describe the irrotational dust component of the universe in terms of a relativistic gradient expansion and transform the resulting synchronous metric to a Newtonian coordinate system. The two metrics are connected via a space-like displacement field and a time-like perturbation, providing a relativistic generalization of the transformation from Lagrangian
B. Audren, D. Blas, J. Lesgourgues, S. Sibiryakov
The role of Lorentz invariance as a fundamental symmetry of nature has been lately reconsidered in different approaches to quantum gravity. It is thus natural to study whether other puzzles of physics may be solved within these proposals. This may be the case for the cosmological constant problem. Indeed, it has been shown that breaking Lorentz invariance pr
Mariele Motta, Ignacy Sawicki, Ippocratis D. Saltas, Luca Amendola
We consider the consequences of having no prior knowledge of the true dark energy model for the interpretation of cosmological observations. The magnitude of redshift-space distortions and weak-lensing shear is determined by the metric on the geodesics of which galaxies and light propagate. We show that, given precise enough observations, we can use these da
Andrew J. Larkoski, Gavin P. Salam, Jesse Thaler
We show how generalized energy correlation functions can be used as a powerful probe of jet substructure. These correlation functions are based on the energies and pair-wise angles of particles within a jet, with (N+1)-point correlators sensitive to N-prong substructure. Unlike many previous jet substructure methods, these correlation functions do not requir
Philip W. Phillips, Brandon W. Langley, Jimmy A. Hutasoit
Since any non-trivial infrared dynamics in strongly correlated electron matter must be controlled by a critical fixed point, we argue that the form of the single-particle propagator can be deduced simply by imposing scale invariance. As a consequence, the unparticle picture proposed by Georgi\cite{georgi} is the natural candidate to describe such dynamics. U
A. Stroe, R. J. van Weeren, H. T. Intema, H. J. A. Röttgering
Giant cluster radio relics are thought to form at shock fronts in the course of collisions between galaxy clusters. Via processes that are still poorly understood, these shocks accelerate or re-accelerate cosmic-ray electrons and might amplify magnetic fields. The best object to study this phenomenon is the galaxy cluster CIZA J2242.8+5301 as it shows the mo
A. Liam Fitzpatrick, Jared Kaplan, David Poland
We derive conformal blocks in an inverse spacetime dimension expansion. In this large D limit, the blocks are naturally written in terms of a new combination of conformal cross-ratios. We comment on the implications for the conformal bootstrap at large D.
- Chiral edge states and fractional charge separation in interacting bosons on a Kagome latticecond-mat.quant-gas
Xue-Feng Zhang, Sebastian Eggert
We consider the extended hard-core Bose-Hubbard model on a Kagome lattice with boundary conditions on two edges. We find that the sharp edges lift the degeneracy and freeze the system into a striped order at 1/3 and 2/3 filling for zero hopping. At small hopping strengths, holes spontaneously appear and separate into fractional charges which move to the edge
Baradhwaj Coleppa, Felix Kling, Shufang Su
We study the implication of the LHC Higgs search results on the Type II Two Higgs-Doublet Model. In particular, we explore the scenarios in which the observed 126 GeV Higgs signal is interpreted as either the light CP-even Higgs $h^0$ or the heavy CP-even Higgs $H^0$. Imposing both theoretical and experimental constraints, we analyze the surviving parameter
- From Hierarchical Partitions to Hierarchical Covers: Optimal Fault-Tolerant Spanners for Doubling Metricscs.DS
Shay Solomon
In this paper we devise an optimal construction of fault-tolerant spanners for doubling metrics. Specifically, for any $n$-point doubling metric, any $\eps > 0$, and any integer $0 \le k \le n-2$, our construction provides a $k$-fault-tolerant $(1+\eps)$-spanner with optimal degree $O(k)$ within optimal time $O(n \log n + k n)$. We then strengthen this resul
Mario Antonelli, Vincenzo Cirigliano, Alberto Lusiani, Emilie Passemar
Hadronic tau decays provide several ways to extract the Cabbibo-Kobashi-Maskawa (CKM) matrix element V_{us}. The most precise determination involves using inclusive tau decays and requires as input the total branching ratio into strange final states. Recent results from B-factories have led to a discrepancy of about 3.4 sigma from the value of V_{us} implied
F. Hautmann
We address aspects of jet physics at the Large Hadron Collider focusing on features of recent jet measurements which challenge the theory. We discuss examples illustrating the role of QCD parton showers, nonperturbative corrections, soft multi-gluon emission.
Zeyuan Allen Zhu, Silvio Lattanzi, Vahab Mirrokni
Motivated by applications of large-scale graph clustering, we study random-walk-based LOCAL algorithms whose running times depend only on the size of the output cluster, rather than the entire graph. All previously known such algorithms guarantee an output conductance of $\tilde{O}(\sqrt{\phi(A)})$ when the target set $A$ has conductance $\phi(A)\in[0,1]$. I
Kwang Sik Jeong, Fuminobu Takahashi
We propose a novel mechanism to suppress the isocurvature perturbations of the QCD axion. The point is that the QCD interactions become strong at an intermediate or high energy scale in the very early Universe, if the Higgs field has a sufficiently large expectation value. The effective QCD scale can be even higher in the presence of extra colored particles.
V. G. Bornyakov, V. K. Mitrjushkin, R. N. Rogalyov
We study the Landau gauge gluon propagator D(p) in the 3d SU(2) lattice gauge theory. We show that in the infinite-volume limit the expectation values over the Gribov region \Omega, are different (in the infrared) from that calculated in the fundamental modular region \Gamma. Also we show that this conclusion does not change when spacing $a$ tends to zero.
Brett Hemenway, Rafail Ostrovsky, Mary Wootters
In this work, we present the first local-decoding algorithm for expander codes. This yields a new family of constant-rate codes that can recover from a constant fraction of errors in the codeword symbols, and where any symbol of the codeword can be recovered with high probability by reading $N^\epsilon$ symbols from the corrupted codeword, where $N$ is the b
Hoi-Kwan Lau, Christian Weedbrook
We extend the formalism of cluster state quantum secret sharing, as presented in Markham and Sanders [Phys. Rev. A 78, 042309 (2008)] and Keet et al. [Phy. Rev. A 82, 062315 (2010)], to the continuous-variable regime. We show that both classical and quantum information can be shared by distributing continuous-variable cluster states through either public or
Jon Chaika, Jon Fickenscher
We show that a residual set of non-degenerate IETs on more than 3 letters is topologically mixing. This shows that there exists a uniquely ergodic topologically mixing IET. This is then applied to show that some billiard flows in a fixed direction in an L-shaped polygon are topologically mixing.
Flavio Chierichetti, Jon Kleinberg, Sigal Oren
An active line of research has considered games played on networks in which payoffs depend on both a player's individual decision and also the decisions of her neighbors. Such games have been used to model issues including the formation of opinions and the adoption of technology. A basic question that has remained largely open in this area is to consider gam
- Derivation of conditions for a Brans-Dicke coupling constant of order unity be consistent with solar system boundsgr-qc
Jean Paul Mbelek
We provide proofs of some assumptions recently made by F. O. Minotti to conclude on the possibility that an additional scalar field minimally coupled to gravity may help to reconcile a Brans-Dicke coupling constant $\omega$ of the order unity with solar system bounds.
L. F. A. Teodoro, V. R. Eke, R. C. Elphic, W. C. Feldman
A detailed comparison is made of results from the Lunar Prospector Neutron Spectrometer (LPNS) and the Lunar Exploration Neutron Detector Collimated Sensors for EpiThermal Neutrons (LEND CSETN). Using the autocorrelation function and power spectrum of the polar count rate maps produced by these experiments, it is shown that the LEND CSETN has a footprint tha
- New perturbative method for solving the gravitational N-body problem in the general theory of relativitygr-qc
Slava G. Turyshev, Viktor T. Toth
We present a new approach to describe the dynamics of an isolated, gravitationally bound astronomical $N$-body system in the weak field and slow-motion approximation of the general theory of relativity. Celestial bodies are described using an arbitrary energy-momentum tensor and assumed to possess any number of internal multipole moments. The solution of the
- Confronting measured near and sub-barrier fusion cross-sections for 20O+12C with a microscopic methodnucl-ex
R. T. deSouza, S. Hudan, V. E. Oberacker, A. S. Umar
Recently measured fusion cross-sections for the neutron-rich system 20O+12C are compared to dynamic, microscopic calculations using time-dependent density functional theory. The calculations are carried out on a three-dimensional lattice and performed both with and without a constraint on the density. The method has no adjustable parameters, and its only inp
- Event mixing does not reproduce single particle acceptance convolutions for nonuniform pseudorapidity distributionsnucl-ex
Lingshan Xu, Chin-Hao Chen, Fuqiang Wang
We point out that the mixed-event method for two-particle acceptance correction, widely used in particle correlation measurements at RHIC and LHC, is wrong in cases where the single particle pseudorapidity distribution is significantly nonuniform. The correct acceptance should be the convolution of two single-particle efficiency$\times$acceptance functions.
- Non-trivial spin-texture of the coaxial Dirac cones on the surface of topological crystalline insulator SnTecond-mat.mtrl-sci
Yung Jui Wang, Wei-Feng Tsai, Hsin Lin, Su-Yang Xu
We present first principles calculations of the nontrivial surface states and their spin-textures in the topological crystalline insulator SnTe. The surface state dispersion on the [001] surface exhibits four Dirac-cones centered along the intersection of the mirror plane and the surface plane. We propose a simple model of two interacting coaxial Dirac cones
- Fuzzy equilibrium existence for Bayesian abstract fuzzy economies and applications to random quasi-variational inequalities with random fuzzy mappingsmath.OC
Monica Patriche
In this paper, we introduce a Bayesian abstract fuzzy economy model and we prove the Bayesian fuzzy equilibrium existence. As applications, we prove the existence of the solutions for two types of random quasi-variational inequalities with random fuzzy mappings and we also obtain random fixed point theorems.
Jack Ireland, Anne K. Tolbert, Richard A. Schwartz, Gordon D. Holman
We compare four different methods of calculating uncertainty estimates in fitting parameterized models to RHESSI X-ray spectra, considering only statistical sources of error. Three of the four methods are based on estimating the scale-size of the minimum in a hypersurface formed by the weighted sum of the squares of the differences between the model fit and
Francisco M Fernández, Javier Garcia
We calculate accurate critical parameters for a class of non-hermitian Hamiltonians by means of the diagonalization method. We study three one-dimensional models and two perturbed rigid rotors with PT symmetry. One of the latter models illustrates the necessity of a more general condition for the appearance of real eigenvalues that we also discuss here.
M. Angeles Perez-Garcia, Joseph Silk, Ue-Li Pen
We propose that interstellar extreme scattering events, usually observed as pulsar scintillations, may be caused by a coherent agent rather than the usually assumed turbulence of $\rm H_2$ clouds. We find that the penetration of a flux of ionizing, positively charged strangelets or quark nuggets into a dense interstellar hydrogen cloud may produce ionization
Sergey I. Senashov, Alexander Yakhno
In this paper, all the known classical solutions of plane perfect plasticity system under Saint Venant -- Tresca -- von Mises yield criterion are associated with some group of point symmetries. The equations of slip-line families for all solutions are constructed, which permits to determine explicitly boundaries of plastic areas. It is shown, how one can det
Mary Alberg, Gerald A. Miller
In a recent Comment [arXiv:1206.3671] on our calculation of the pion contributions to the self-energy of the nucleon [arXiv:1201.4184], Ji, Melnitchouk and Thomas (JMT) correctly state that we obtain the same result as given by the pseudovector (PV) theory. We point out that this result is expected by the equivalence theorem, since our pion-nucleon effective
Benjamin C. Rislow, Carl E. Carlson
The $\gamma Z$-box diagram for parity violating elastic $e$-$p$ scattering has recently undergone a thorough analysis by several research groups. Though all now agree on the analytic form of the diagram, the numerical results differ due to the treatment of the structure functions, $F_{1,2,3}^{\gamma Z}(x,Q^2)$. Currently, $F_{1,2,3}^{\gamma Z}(x,Q^2)$ at low
P. A. Sturrock, E. Fischbach, J. T. Gruenwal, D. Javorsek
Claims by the DAMA (DArk MAtter) collaboration to have detected an annually varying signal consistent with models of dark matter appear to be at variance with results from other dark-matter searches. To further understand the DAMA results, we have carried out an independent analysis of DAMA data reconstructed from published figures. In addition to reexaminin
M. Iskin
We analyze the ground-state phase diagram of two-component Fermi gases loaded into a two-dimensional checkerboard superlattice, i.e. a double-well optical lattice, potential within the BCS mean-field theory. We show that, by coupling the two s-wave sublattice superfluid order parameters, a checkerboard potential gives rise to a Hamiltonian that has the form
Ronald Petrlic, Stephan Sekula
We present a solution to the problem of privacy invasion in a multiparty digital rights management scheme. (Roaming) users buy content licenses from a content provider and execute it at any nearby content distributor. Our approach, which does not need any trusted third party--in contrast to most related work on privacy-preserving DRM--is based on a re-encryp
Mohit Singh, Nisheeth K. Vishnoi
In this paper we study the problem of computing max-entropy distributions over a discrete set of objects subject to observed marginals. Interest in such distributions arises due to their applicability in areas such as statistical physics, economics, biology, information theory, machine learning, combinatorics and, more recently, approximation algorithms. A k
Tim Johannsen
According to the no-hair theorem, astrophysical black holes are uniquely described by the Kerr metric. In order to test this theorem with observations in either the electromagnetic or gravitational-wave spectra, several Kerr-like spacetimes have been constructed which describe potential deviations from the Kerr spacetime in parametric form. For electromagnet
Sergey V. Zharikov, Dmitry A. Zyuzin, Yuri A. Shibanov, Ronald E. Mennickent
The young radio pulsar J1124-5916 is associated with a Cas A like supernova remnant G292.0+1.8. It powers a compact torus-like pulsar wind nebula with a jet first detected in X-rays and then identified in the optical and mid-infrared. We carried out deep near-infrared observations of the pulsar field to identify the pulsar and its nebula in this range. The d
Ole Andersson, Hoshang Heydari
Geometric effects make evolution time vary for different evolution curves that connect the same two quantum states. Thus, it is important to be able to control along which path a quantum state evolve to achieve maximal speed in quantum calculations. In this paper we establish fundamental relations between Hamiltonian dynamics and Riemannian structures on the
Sergey Loyka, Victoria Kostina, Francois Gagnon
Convexity properties of error rates of a class of decoders, including the ML/min-distance one as a special case, are studied for arbitrary constellations, bit mapping and coding. Earlier results obtained for the AWGN channel are extended to a wide class of noise densities, including unimodal and spherically-invariant noise. Under these broad conditions, symb
Arman Margaryan, Roxanne P Springer
The X(3872) has non-charmonium-like properties, such as decay processes that seem to violate isospin, and a mass that lies unexpectedly close to the neutral-D-plus-neutral-D-excited-state threshold. An EFT that includes both charmonium-like (short distance) and molecule-like (meson bound state) properties is used to analyze the X(3872) as it is produced in t
- Synthesis of Dispersed Metal Particles for Applications in Photovoltaics, Catalysis, and Electronicscond-mat.mtrl-sci
I. Sevonkaev, V. Privman, D. Goia
In colloid and nanoparticle chemistry, particle size, shape, crystallinity, surface morphology and composition are controlled by employing the mechanisms of burst nucleation, diffusional growth, aggregation, or their combinations. Here we review and survey practical examples of recently developed methods for preparing metal colloids and nanoparticles for ind
Tomasz Sowiński, Tobias Grass, Omjyoti Dutta, Maciej Lewenstein
We study spin-1/2 fermions, interacting via a two-body contact potential, in a one-dimensional harmonic trap. Applying exact diagonalization, we investigate their behavior at finite interaction strength, and discuss the role of the ground-state degeneracy which occurs for sufficiently strong repulsive interaction. Even low temperature or a completely depolar
- Regularization of the slip length divergence in water nanoflows by inhomogeneities at the Angstrom scalecond-mat.soft
Marcello Sega, Mauro Sbragaglia, Luca Biferale, Sauro Succi
We performed non-equilibrium Molecular Dynamics simulations of water flow in nano-channels with the aim of discriminating {\it static} from {\it dynamic} contributions of the solid surface to the slip length of the molecular flow. We show that the regularization of the slip length divergence at high shear rates, formerly attributed to the wall dynamics, is c
Jack S. Calcut, Patrick V. Haggerty
We study connected sum at infinity on smooth, open manifolds. This operation requires a choice of proper ray in each manifold summand. In favorable circumstances, the connected sum at infinity operation is independent of ray choices. For each m at least 3, we construct an infinite family of pairs of m-manifolds on which the connected sum at infinity operatio
Johannes Otterbach, Matthias Moos, Dominik Muth, Michael Fleischhauer
The coupling of weak light fields to Rydberg states of atoms under conditions of electromagnetically induced transparency (EIT) leads to the formation of Rydberg polaritons which are quasi-particles with tunable effective mass and long-range interactions. Confined to one spatial dimension their low energy physics is that of a moving-frame Luttinger liquid wh
C. Ryu, A. A. Blinova, P. W. Blackburn, M. G. Boshier
We report the creation of a pair of Josephson junctions on a toroidal dilute gas Bose-Einstein condensate (BEC), a configuration that is the cold atom analog of the well-known dc superconducting quantum interference device (SQUID). We observe Josephson effects, measure the critical current of the junctions, and find dynamic behavior that is in good agreement
Chen Zhang, Chris H. Greene
Confinement induced resonances (CIR) in quasi-1D systems have been theoretically predicted and observed in various ultracold atomic gases. Here a regularized local frame transformation method is developed to treat CIR in a quasi-1D system that has an arbitrary transverse trap shape in general. The method is applied to predict the CIR position in a system who
Hongzhong Zhang
The drawdown process of an one-dimensional regular diffusion process $X$ is given by $X$ reflected at its running maximum. The drawup process is given by $X$ reflected at its running minimum. We calculate the probability that a drawdown proceeds a drawup in an exponential time-horizon. We then study the law of the occupation times of the drawdown process and
P. Shanmugavadivu, V. Sivakumar
In this paper, a novel method for edge detection of microcalcification clusters in mammogram images is presented using the concept of Fractal Dimension and Hurst co-efficient that enables to locate the microcalcifications in the mammograms. This technique detects the edges accurately than the ones obtained by the conventional Sobel method. Generally, Sobel m
H. Najafi, M. S. Moslehian
We investigate the deformation of involution and multiplication in a unital $C^*$-algebra when its norm is fixed. Our main result is to present all multiplications and involutions on a given $C^*$-algebra $\mathcal{A}$ under which $\mathcal{A}$ is still a $C^*$-algebra whereas we keep the norm unchanged. For each invertible element $a\in\mathcal{A}$ we also
Christine A. Muschik, Simon Moulieras, Adrian Bachtold, Maciej Lewenstein
Position measurements at the quantum level are vital for many applications, but also challenging. Typically, methods based on optical phase shifts are used, but these methods are often weak and difficult to apply to many materials. An important example is graphene, which is an excellent mechanical resonator due to its small mass and an outstanding platform f
Sónia Dias, Paula Brito
Symbolic Data Analysis works with variables for which each unit or class of units takes a finite set of values/categories, an interval or a distribution (an histogram, for instance). When to each observation corresponds an empirical distribution, we have a histogram-valued variable; it reduces to the case of an interval-valued variable if each unit takes val