June 2008 arXiv papers — page 9

Stefano Pirandola, Samuel L. Braunstein, Seth Lloyd

We provide a simple description of the most general collective Gaussian attack in continuous-variable quantum cryptography. In the scenario of such general attacks, we analyze the asymptotic secret-key rates which are achievable with coherent states, joint measurements of the quadratures and one-way classical communication.

Ghadamali Bagherikaram, Abolfazl S. Motahari, Amir K. Khandani

In this paper, we consider a scenario where a source node wishes to broadcast two confidential messages for two respective receivers, while a wire-tapper also receives the transmitted signal. This model is motivated by wireless communications, where individual secure messages are broadcast over open media and can be received by any illegitimate receiver. The

V. Belokurov, N. W. Evans, P. C. Hewett, A. Moiseev

We present discovery images, together with follow-up imaging and spectroscopy, of two large separation gravitational lenses found by our survey for wide arcs (the CASSOWARY). The survey exploits the multicolor photometry of the Sloan Digital Sky Survey to find multiple blue components around red galaxies. CASSOWARY~2 (or "the Cheshire Cat") is compos

Christoph M. Puetter, Michael J. Lawler, Hae-Young Kee

We present a theory of the anisotropy tuned quantum phase transition between spin nematic and spin-Peierls phases in S=1 systems with significant bi-quadratic exchange interactions. Based on quantum Monte Carlo studies on finite size systems, [K. Harada et al., J. Phys. Soc. Jpn. 76, 013703 (2007)] it has been proposed that this phase transition is second or

Carmelo Evoli, Stefania Salvadori, Andrea Ferrara

We discuss the 6Li abundance evolution within a hierarchical model of Galaxy formation which correctly reproduces the [Fe/H] distribution of metal-poor halo stars. Contrary to previous findings, we find that neither the level (6Li/H=6x10^-12) nor the flatness of the 6Li distribution with [Fe/H] can be reproduced under the most favourable conditions by any mo

A. V. Dodonov, L. C. Celeri, F. Pascoal, M. D. Lukin

We study theoretically the non-stationary circuit QED system in which the artificial atom transition frequency has a small periodic modulation in time, prescribed externally. We show that, in the dispersive regime, when the modulation periodicity meets the `resonances', the dynamics may be described by the dynamical Casimir effect, Jaynes-Cummings or Ant

Eyo Eyo Ita

In this paper we carry out a quantization of gravity coupled to massless spin 1/2 fermions through the instanton representation of Plebanski gravity. We have constructed a Hilbert space of states for this model, and we have computed the Hamilton's equations of motion. The classical equations appear, at a superficial level, to be consistent with the quant

Eyo Eyo Ita

In this paper we quantize the Klein--Gordon scalar field coupled to gravity in the instanton representation for spatially homogeneous variables. The construction provides a well-defined Hilbert space of states for generic self-interaction potential V, with a direct link to the semiclassical limit below the Planck scale. Additionally, we compute the Hamilton&

Eyo Eyo Ita

In this paper we show that the instanton representation of Plebanski gravity exhibits a Hilbert space of harmonic oscillator-like coherent states. We put in place the formalism and carry out the construction of the states, and we elucidate on their physical interpretation. Additionally, we provide an invertible map between the Ashtekar variables and this Hil

Frank Petriello, Kathryn M. Zurek

We study whether spin-independent scattering of weakly-interacting massive particles (WIMPs) with nuclei can account for the annual modulation signal reported by DAMA. We consider both elastic and inelastic scattering processes. We find that there is a region of WIMP parameter space which can simultaneously accommodate DAMA and the null results of CDMS, CRES

Anupama Atre, Marcela Carena, Tao Han, Jose Santiago

Recent developments in models with warped extra dimensions have opened new possibilities for vector-like quark studies at hadron colliders. These new vector-like quarks can mix sizably with light Standard Model quarks without violating low energy constraints. We perform a model-independent analysis to determine the Tevatron reach in the search for new quarks

Ljiljana Janicijevic, Suzana Topuzoski

Expressions describing the vortex beams, which are generated in a process of Fresnel diffraction of a Gaussian beam, incident out of waist on a fork-shaped gratings of arbitrary integer charge p, and vortex spots in the case of Fraunhofer diffraction by these gratings are deduced. The common general transmission function of the gratings is defined and specia

Pavel Lougovski, S. J. van Enk

We show how a straightforward Bayesian updating procedure allows one to detect and quantify entanglement from any finite set of measurement results. The measurements do not have to be tomographically complete, and may consist of POVMs rather than von Neumann measurements. One obtains a probability that one's state is entangled and an estimate of any desi

J. I. Kapusta, T. Springer

We study the shear mode in the gauge/gravity correspondence at finite temperature. First, we confirm the general formula for the shear viscosity in an arbitrary background metric which includes a black hole in the fifth dimension. We then derive a general formula for the shear mode relaxation time which appears in the theory of relativistic dissipative fluid

A. Font-Ribera, J. Miralda-Escudé, I. Ribas

A new model for the formation of Jovian planets is proposed. We consider planets forming at large distances from a protostar (>100 AU) through direct fragmentation of a gas cloud, by the same formation mechanism as wide stellar and brown dwarf binaries. We model the gravitational evolution of a system of these distant planets and a second population formed i

Jorge Casalderrey-Solana, David Mateos

We show that if a flavour-less vector meson remains bound after deconfinement, and if its limiting velocity in the quark-gluon plasma is subluminal, then this meson produces a distinct peak in the spectrum of thermal photons emitted by the plasma. We also demonstrate that this effect is a universal property of all strongly coupled, large-Nc plasmas with a gr

Eugene Lerman

The first goal of this survey paper is to argue that if orbifolds are groupoids, then the collection of orbifolds and their maps has to be thought of as a 2-category. Compare this with the classical definition of Satake and Thurston of orbifolds as a 1-category of sets with extra structure and/or with the "modern" definition of orbifolds as proper et

M. E. McCulloch

The flyby anomalies are unexplained velocity jumps of 3.9, -4.6, 13.5, -2, 1.8 and 0.02 mm/s observed near closest approach during the Earth flybys of six spacecraft. These flybys are modelled here using a theory that assumes that inertia is due to a form of Unruh radiation, and varies with acceleration due to a Hubble-scale Casimir effect. Considering the a

I. Hambleton, L. R. Taylor, E. B. Williams

For any finite group G, we define a bivariant functor from the Dress category of finite G-sets to the conjugation biset category, whose objects are subgroups of G, and whose morphisms are generated by certain bifree bisets. Any additive functor from the conjugation biset category to abelian groups yields a Mackey functor by composition. We characterize the M

Vesselin Drensky, Jie-Tai Yu

Let $K[x,y]$ be the polynomial algebra in two variables over an algebraically closed field $K$. We generalize to the case of any characteristic the result of Furter that over a field of characteristic zero the set of automorphisms $(f,g)$ of $K[x,y]$ such that $\max\{\text{deg}(f),\text{deg}(g)\}=n\geq 2$ is constructible with dimension $n+6$. The same resul

Aisling Kenny

For any finite, real reflection group $W$, we construct a geometric basis for the homology of the corresponding non-crossing partition lattice. We relate this to the basis for the homology of the corresponding intersection lattice introduced by Björner and Wachs in \cite{BW} using a general construction of a generic affine hyperplane for the central hyperpla

Andrew J. Heim, Niels Gronbech-Jensen, Edward M. Kober, Timothy C. Germann

After making modifications to the Reactive Empirical Bond Order potential for Molecular Dynamics (MD) of Brenner et al. in order to make the model behave in a more conventional manner, we discover that the new model exhibits detonation instability, a first for MD. The instability is analyzed in terms of the accepted theory.

Thomas Jorg, Florent Krzakala, Jorge Kurchan, A. C. Maggs

We study first order quantum phase transitions in mean-field spin glasses. We solve the quantum Random Energy Model using elementary methods and show that at the transition the eigenstate suddenly projects onto the unperturbed ground state and that the gap between the lowest states is exponentially small in the system size. We argue that this is a generic fe

Bo Feng, Gang Yang

In unitarity cut method, compact input of on-shell tree level amplitudes is crucial to simplify calculations. Although BCFW on-shell recursion relation gives very compact tree level amplitudes, they usually contain spurious poles. In this paper, we present a method to deal with this issue and provide explicit simple algebraic functions for various coefficien

Zbigniew Idziaszek, Tommaso Calarco, Paul S. Julienne, Andrea Simoni

We study atom-ion scattering in the ultracold regime. To this aim, an analytical model based on the multichannel quantum defect formalism is developed and compared to close-coupled numerical calculations. We investigate the occurrence of magnetic Feshbach resonances focusing on the specific 40Ca+ - Na system. The presence of several resonances at experimenta

Roldao da Rocha, Waldyr A. Rodrigues

In a previous paper we investigate a Lagrangian field theory for the gravitational field (which is there represented by a section g^a of the orthonormal coframe bundle over Minkowski spacetime. Such theory, under appropriate conditions, has been proved to be equivalent to a Lorentzian spacetime structure, where the metric tensor satisfies Einstein field equa

Jostein Paulsen

This survey treats the problem of ruin in a risk model when assets earn investment income. In addition to a general presentation of the problem, topics covered are a presentation of the relevant integro-differential equations, exact and numerical solutions, asymptotic results, bounds on the ruin probability and also the possibility of minimizing the ruin pro

Oliver Johnson

We analyse the properties of the Principal Fitted Components (PFC) algorithm proposed by Cook. We derive theoretical properties of the resulting estimators, including sufficient conditions under which they are $\sqrt{n}$-consistent, and explain some of the simulation results given in Cook's paper. We use techniques from random matrix theory and perturbat

Julian Adamek, David Campo, Jens C. Niemeyer, Renaud Parentani

The sensitivity of inflationary spectra to initial conditions is addressed in the context of a phenomenological model that breaks Lorentz invariance by dissipative effects above some threshold energy $Λ$. These effects are obtained dynamically by coupling the fluctuation modes to extra degrees of freedom which are unobservable below $Λ$. Because of the stron

Salvatore Capozziello, Mariafelicia De Laurentis

The emission of gravitational waves from a system of massive objects interacting on elliptical, hyperbolic and parabolic orbits is studied in the quadrupole approximation. Analytical expressions are then derived for the gravitational wave luminosity, the total energy output and gravitational radiation amplitude. A crude estimate of the expected number of eve

Lukas Meier, Sara van de Geer, Peter Bühlmann

We propose a new sparsity-smoothness penalty for high-dimensional generalized additive models. The combination of sparsity and smoothness is crucial for mathematical theory as well as performance for finite-sample data. We present a computationally efficient algorithm, with provable numerical convergence properties, for optimizing the penalized likelihood. F

Akos Rapp, Gergely Zarand

We apply a semiclassical approach to express finite temperature dynamical correlation functions of gapped spin models analytically. We show that the approach of [A. Rapp, G. Zarand, Phys. Rev. B 74, 014433 (2006)] can also be used for the S=1 antiferromagnetic Heisenberg chain, whose lineshape can be measured experimentally. We generalize our calculations to

Adam Bednorz, Wolfgang Belzig

We propose a derivation of the full counting statistics of electronic current based on a positive-operator-valued measure. Our approach justifies the Levitov-Lesovik formula in the long-time limit, but can be generalized to the detection of finite-frequency noise correlations. The combined action of the projection postulate and the quantum formula for curren

Wei Xue, Bin Chen

In this paper, we discuss the non-Guassianity originated from the $α$-vacuum on the CMB anisotropy. For $α$-vacuum, there exist correlation between points in the acausal two patches of de Sitter spactime. Such kind of correlation can lead to large local form non-Guassianity in $α$-vacuum. For the single field slow-roll inflationary scenario, the spacetime is

Evandro C. Silva, Diogenes Galetti

Discrete quantum phase space formalism is used to discuss some basic aspects of the spin tunneling occurring in Fe8 magnetic cluster by means of Wigner functions as well as Husimi distributions. Those functions were obtained for sharp angle states and symmetric combinations of the lowest energy doublet with the application of an external magnetic field. The

V. Bozza

We present an exhaustive numerical investigation of the optical caustics in gravitational lensing by a spinning black hole for an observer at infinity. Besides the primary caustic, we examine higher order caustics, formed by photons performing one or several loops around the black hole. Our investigation covers the whole parameter space, including the black

J. Manninen, F. Becattini

A comprehensive and detailed analysis of hadronic abundances measured in Au-Au collisions at RHIC at sqrt(s)_NN = 130 and 200 GeV is presented. The rapidity densities measured in the central rapidity region have been fitted to the statistical hadronization model and the chemical freeze-out parameters determined as a function of centrality, using data from ex

A. Bottino, F. Donato, N. Fornengo, S. Scopel

The most recent results from direct searches for dark matter particles in the galactic halo are examined in terms of an effective Minimal Supersymmetric extension of the Standard Model at the electroweak scale without gaugino masses unification. We show that the annual modulation effect at 8.2 $σ$ C.L. recently presented by the DAMA Collaboration, as the res

R. Mizuk, R. Chistov

We report the first observation of two resonance-like structures in the pi+ chi_c1 invariant mass distribution near 4.1 GeV/c^2 in exclusive B0-bar --> K- pi+ chi_c1 decays. From a Dalitz plot analysis in which the pi+ chi_c1 mass structures are represented by Breit-Wigner resonance amplitudes, we determine masses and widths of: M_1 = (4051 +-14 +20-41) MeV/

Thomas Willwacher, Damien Calaque

We prove Kontsevich's cyclic formality conjecture.

Garrisi Daniele

We give a definition of the spectral flow for paths of bounded essentially hyperbolic operators on a Banach space. The spectral flow induces a group homomorphism on the fundamental group of every connected component of the space of essentially hyperbolic operators. We prove that this homomorphism completes the exact homotopy sequence of a Serre fibration. Th

F. Wolfgramm, X. Xing, A. Cerè, A. Predojević

We demonstrate a high-brightness source of pairs of indistinguishable photons based on a type-II phase-matched doubly-resonant optical parametric oscillator operated far below threshold. The cavity-enhanced down-conversion output of a PPKTP crystal is coupled into two single-mode fibers with a mode coupling efficiency of 58%. The high degree of indistinguish

Rachel Mandelbaum, Cheng Li, Guinevere Kauffmann, Simon D. M. White

We compute two-point correlation functions and measure the shear signal due to galaxy-galaxy lensing for 80,000 optically identified and 5,700 radio-loud AGN from Data Release 4 (DR4) of the Sloan Digital Sky Survey. Halo occupation models are used to estimate halo masses and satellite fractions for these two types of AGN. The large sample size allows us to

R. Gray, J. Dunning-Davies

This article has been withdrawn by arXiv administrators due to excessive unattributed and verbatim text overlap with the pre-existing Wikipedia article on redshift

Juan A. Bonachela, Miguel A. Munoz

Stochastic sandpiles self-organize to a critical point with scaling behavior different from directed percolation (DP) and characterized by the presence of an additional conservation law. This is usually called C-DP or Manna universality class. There remains, however, an exception to this universality principle: a sandpile automaton introduced by Maslov and Z

Alex Degtyarev, Ilia Itenberg, Viatcheslav Kharlamov

Our main results concern complete intersections of three real quadrics. We prove that the maximal number $B^0_2(N)$ of connected components that a regular complete intersection of three real quadrics in $\Bbb{P}^N$ can have differs at most by one from the maximal number of ovals of the submaximal depth $[(N-1)/2]$ of a real plane projective curve of degree $

Alessandro Ballestrero, Giuseppe Bevilacqua, Ezio Maina

Higgs production in association with a $W$ boson and two energetic tag jets at the LHC is studied for $M_H = 120$ \GeV, with the Higgs decaying to $b\bar{b}$ and the $W$ to $\ellν$ ($\ell = e, μ$), guaranteeing high trigger efficiency. All parton level backgrounds are analyzed, including the effect of fake $b$--tagging. We discuss two detection strategies: i

Adi Armoni, Asad Naqvi

We propose a three dimensional non-supersymmetric theory that is conformal in the large N limit. In a certain well defined bosonic sub-sector of gauge invariant operators, this theory is planar equivalent to the theory recently proposed by Aharony, Bergman, Jafferis and Maldacena as the theory on multiple M2 branes at an orbifold singularity. We discuss the

Rozalia Lukacs, Jozsef Hegedus, Sandor Kugler

Atomic scale computer simulations on structures and photo induced volume changes of flatly and obliquely deposited amorphous selenium films have been carried out in order to understand how the properties of chalcogenide glasses are influenced by their preparation method. Obliquely deposited a-Se thin films contain more coordination defects, larger voids than

Vicky Henderson, David Hobson

In this article we study an optimal stopping/optimal control problem which models the decision facing a risk-averse agent over when to sell an asset. The market is incomplete so that the asset exposure cannot be hedged. In addition to the decision over when to sell, the agent has to choose a control strategy which corresponds to a feasible wealth process. We

N. Camara, G. Rius, J. -R. Huntzinger, A. Tiberj

We present an innovative method of selective epitaxial growth of few layers graphene (FLG) on a pre-patterned SiC substrate. The methods involves, successively, the sputtering of a thin AlN layer on top of a mono-crystalline SiC substrate and, then, patterning it with e-beam lithography (EBL) and wet etching. The sublimation of few atomic layers of Si from t

V. D. Rusov, D. Vlasenko

Basing on the Chetaev's theorem on stable trajectories in dynamics in the presence of dissipative forces we obtain a generalized stability condition for Hamiltonian systems that has the form of the Schrodinger equation. We show that the energy of the dissipative forces generating generalized Chetaev's stability condition exactly coincides with Bohm&#

A. A. Akhundov

The numerical study of QED radiative corrections in the low x region for the H1 experiment at HERA was performed. The analytical program TERAD91 was used to obtain the values of the radiative correction factor for the first measurement of the proton structure function F2(x,Q2) in the range x= 10^{-2} - 10^{-4} and 5 < Q2 < 80 GeV2.

Toshio Sumi, Mitsuhiro Miyazaki, Toshio Sakata

High dimensional array data, tensor data, is becoming important in recent days. Then maximal rank of tensors is important in theory and applications. In this paper we consider the maximal rank of 3 tensors. It can be attacked from various viewpoints, however, we trace the method of Atkinson-Stephens(1979) and Atkinson-Lloyd(1980). They treated the problem in

Kazuyuki Furuuchi, Sheng-Yu Darren Shih, Tomohisa Takimi

We investigate space-time supersymmetry of the model of multiple M2-branes proposed by Bagger-Lambert and Gustavsson. When there is a central element in Lie 3-algebra, the model possesses an extra symmetry shifting the fermions in the central element. Together with the original worldvolume supersymmetry transformation, we construct major part of the eleven d

T. Cuhadar-Donszelmann, M. Karagoz Unel, V. E. Ozcan, S. Sultansoy

We evaluate the LHC discovery potential for the fourth family Standard Model neutrinos in the process $pp\to Z/h\toν_{4}{\barν_{4}}\to WμWμ$. We show that, depending on their masses, the simultaneous discovery of both the Higgs boson and the heavy neutrinos is probable at early stages of LHC operation. Results are presented for both Majorana and Dirac type f

Motohiko Kusakabe, Toshitaka Kajino, Takashi Yoshida, Tatsushi Shima

A recent measurement of $^4$He photodisintegration reactions, $^4$He($γ$,$p$)$^3$H and $^4$He($γ$,$n$)$^3$He with laser-Compton photons shows smaller cross sections than those estimated by other previous experiments at $E_γ\lesssim 30$ MeV. We study big-bang nucleosynthesis with the radiative particle decay using the new photodisintegration cross sections of

J. A. Bergstra, C. A. Middelburg

We study shedding in the setting of data linkage dynamics, a simple model of computation that bears on the use of dynamic data structures in programming. Shedding is complementary to garbage collection. With shedding, each time a link to a data object is updated by a program, it is determined whether or not the link will possibly be used once again by the pr

Lusaka Bhattacharya, Pradip Roy

We expose the role of collisional energy loss on high $p_T$ photon data measured by PHENIX collaboration by calculating photon yield in jet plasma interaction. The phase space distribution of the participating jet is dynamically evolved by solving Fokker-Planck equation. It is shown that the data is reasonably well reproduced when contributions from all the

A. Mason, R. Chatterjee, L. Fortunato, A. Vitturi

Mirror isobars $^7$Li and $^7$Be are investigated in a dicluster model. The magnetic dipole moments and the magnetic dipole response to the continuum are calculated in this framework. The magnetic contribution is found to be small with respect to electric dipole and quadrupole excitations even at astrophysical energies, at a variance with the case of deutero

Seung-il Nam, Ji-Hyoung Park, Atsushi Hosaka, Hyun-Chul Kim

We investigate the photoproduction of Lambda(1405,1/2^-) = Lambda* off the proton target using the effective Lagrangian in the Born approximation. We observed that, depending on the choice of the K* N Lambda* coupling strength, the total cross section becomes 0.1 <~ sigma_Lambda* <~ 0.2 mu b near the threshold and starts to decrease beyond E_gamma ~ 1.6 GeV,

Jérôme Los

We construct infinite sequences of pseudo-Anosov homeomorphisms without fixed points and leaving invariant a sequence of orientable measured foliations on the same topological surface and the same stratum of the space of abelian differentials. The existence of such sequences show that all pseudo-Anosov homeomorphisms fixing orientable measured foliations can

Shinya Katayama, Akito Kobayashi, Yoshikazu Suzumura

A zero-gap state (ZGS) has been found in a bulk system of two-dimensional organic conductor, $α$-(BEDT-TTF)$_2$I$_3$ salt which consists of four sites of donor molecules in a unit cell. In the present paper, the characteristic of the ZGS is analyzed in detail and the electronic properties are examined in the vicinity of the contact point where the conduction

A. M. Shirokov, A. I. Mazur, J. P. Vary, E. A. Mazur

The $J$-matrix inverse scattering approach can be used as an alternative to a conventional $R$-matrix in analyzing scattering phase shifts and extracting resonance energies and widths from experimental data. A great advantage of the $J$-matrix is that it provides eigenstates directly related to the ones obtained in the shell model in a given model space and

Caroline J. Klivans, Kathryn L. Nyman, Bridget E. Tenner

We study degree sequences for simplicial posets and polyhedral complexes, generalizing the well-studied graphical degree sequences. Here we extend the more common generalization of vertex-to-facet degree sequences by considering arbitrary face-to-flag degree sequences. In particular, these may be viewed as natural refinements of the flag f-vector of the pose

Andrey N. Todorov

There is a natural sequence of CY manifolds that are double covers of the projective g dimensional spaces ramified over 2g+2 hyperplanes. We observe that some of them are obtained as quotient of the action of the semi-direct product of g-1 copies of cyclic Z/2Z groups with the symmetric g group on the product of g-copies of hyper-elliptic curves of genus g.

Avi Shporer, Gaspar A. Bakos, Francois Bouchy, Frederic Pont

We report the discovery of a planet transiting a moderately faint (V=12.3 mag) late F star, with an orbital period of 3.92289 +/- 0.00004 days. From the transit light curve and radial velocity measurements we determine that the radius of the planet is R_p = 1.40 +/- 0.06 R_Jup and that the mass is M_p = 0.78 +/- 0.09 M_Jup. The density of the new planet, rho

Hongsheng Zhang, Heng Yu, Hyerim Noh, Zong-Hong Zhu

The cosmic acceleration is one of the most significant cosmological discoveries over the last century. The two categories of explanation are exotic component (dark energy) and modified gravity. We constrain the two types of model by a joint analysis with perturbation growth and direct $H(z)$ data. Though the minimal $χ^2$ of the $Λ$CDM is almost the same as

Tetsuro Yamamoto, Masaru Shibata, Keisuke Taniguchi

We report our new code (named SACRA) for numerical relativity simulations in which an adaptive mesh refinement algorithm is implemented. In this code, the Einstein equations are solved in the BSSN formalism with a fourth-order finite differencing, and the hydrodynamic equations are solved by a third-order high-resolution central scheme. The fourth-order Rung

László Á. Gergely

The high value of brane tension has a crucial role in recovering Einstein&#39;s general relativity at low energies. In the framework of a recently developed formalism with variable brane tension one can pose the question, whether it was always that high? In analogy with fluid membranes, in this paper we allow for temperature dependent brane tension, accordin

Mark M. Wilde

Quantum error-correcting codes will be the ultimate enabler of a future quantum computing or quantum communication device. This theory forms the cornerstone of practical quantum information theory. We provide several contributions to the theory of quantum error correction--mainly to the theory of &#34;entanglement-assisted&#34; quantum error correction where

Andrew Frohmader

Notions of sesquiconstructible complexes and odd iterated stellar subdivisions are introduced, and some of their basic properties are verified. The Charney-Davis conjecture is then proven for odd iterated stellar subdivisions of sesquiconstructible balls and spheres.

Jan Arpe, Elchanan Mossel

We prove that the class of functions g:{-1,+1}^n -> {-1,+1} that only depend on an unknown subset of k<<n variables (so-called k-juntas) is agnostically learnable from a random walk in time polynomial in n, 2^{k^2}, epsilon^{-k}, and log(1/delta). In other words, there is an algorithm with the claimed running time that, given epsilon, delta > 0 and access to

Christian Gothgen, Rafal Oszwaldowski, Athos Petrou, Igor Zutic

We formulate an analytical model for vertical-cavity surface-emitting lasers (VCSELs) with injection (pump) of spin-polarized electrons. Our results for two different modes of carrier recombination allow for a systematic analysis of the operational regimes of the spin-VCSELs. We demonstrate that threshold reduction by electrically-pumped spin-polarized carri

Andrew Frohmader

For Turán&#39;s (3, 4)-conjecture, in the case of n = 3k+1 vertices, (.5)6^{k-1} non-isomorphic complexes are constructed that attain the conjecture. In the case of n = 3k+2 vertices, 6^{k-1} non-isomorphic complexes are constructed that attain the conjecture.

Pascal Lefevre, Daniel Li, Herve Queffelec, Luis Rodriguez-Piazzaa

We compare the compactness of composition operators on $H^2$ and on Orlicz-Hardy spaces $H^Ψ$. We show in particular that exists an Orlicz function $Ψ$ such that $H^{3+\eps} \subseteq H^Ψ\subseteq H^3$ for every $\eps >0$, and a composition operator $C_ϕ$ which is compact on $H^3$ and on $H^{3+\eps}$, but not compact on $H^Ψ$.

P. M. Echternach, M. D. Shaw, J. Bueno, P. K. Day

We propose a sensitive new detector based on Cooper pair breaking in a superconductor. The quantum capacitor detector (QCD) exploits the extraordinary sensitivity of superconducting single-electron devices to the presence of quasiparticles generated by pair-breaking photons. This concept would enable single-photon detection at far-IR and sub-millimeter frequ

Pascal Lefevre, Daniel Li, Herve Queffelec, Luis Rodriguez-Piazzaa

To appear in J. Funct. Spaces and Appl.

Pascal Lefevre, Daniel Li, Herve Queffelec, Luis Rodriguez-Piazza

To appear in J. Functional Analysis

Alejandro Gangui

Since the time of ancient civilizations, cosmology had a privileged place within the various artistic and literary manifestations. The Divine Comedy by Dante Alighieri, one of the masterpieces in literature and thought of the Western World, is organized on the image of the cosmos of the XIII century, which is analyzed in this article.

MiniBooNE Collaboration

The MiniBooNE neutrino detector was designed and built to look for muon-neutrino to electron-neutrino oscillations in the mixing parameter space region where the LSND experiment reported a signal. The MiniBooNE experiment used a beam energy and baseline that were an order of magnitude larger than those of LSND so that the backgrounds and systematic errors wo

Donatello Materassi, Murti Salapaka, Michele Basso

A weak form of the Circle Criterion for Lur&#39;e systems is stated. The result allows prove global boundedness of all system solutions. Moreover such a result can be employed to enlarge the set of nonlinearities for which the standard Circle Criterion can guarantee absolute stability.

I. M. Bradaric, M. S. Laad, F. V. Kusmartsev, K. Yoshii

We have experimentally found related anomalies in electrical resistivity, dc and ac magnetic susceptibility, appearing deeply within ferromagnetically ordered state in SrRuO3. Lack of Jahn-Teller distortion in this regime rules out conventional orbital order, forcing one to describe these in terms of an orbital liquid ground state coexisting with ferromagnet

R. V. E. Lovelace, M. M. Romanova, A. W. Barnard

This paper investigates the influence of magneto-centrifugally driven or simply magnetic winds of rapidly-rotating, strongly-magnetized T Tauri stars in causing the inward or outward migration of close-in giant planets. The azimuthal ram pressure of the magnetized wind acting on the planet tends to increase the planet&#39;s angular momentum and cause outward

R. Moosa, T. Scanlon

The notion of prolongation of an algebraic variety is developed in an abstract setting that generalises the difference and (Hasse) differential contexts. An interpolating map that compares the prolongation spaces with algebraic jet spaces is introduced and studied.

H. J. Kimble

Quantum networks offer a unifying set of opportunities and challenges across exciting intellectual and technical frontiers, including for quantum computation, communication, and metrology. The realization of quantum networks composed of many nodes and channels requires new scientific capabilities for the generation and characterization of quantum coherence a

Neil D. Christensen, Claude Duhr

In this paper we present FeynRules, a new Mathematica package that facilitates the implementation of new particle physics models. After the user implements the basic model information (e.g. particle content, parameters and Lagrangian), FeynRules derives the Feynman rules and stores them in a generic form suitable for translation to any Feynman diagram calcul

F. M. Souza, J. A. Gomez

We calculate current, spin current and tunnel magnetoresistance (TMR) for a quantum dot coupled to ferromagnetic leads in the presence of a square wave of bias voltage. Our results are obtained via time-dependent nonequilibrium Green function. Both parallel and antiparallel lead magnetization alignments are considered. The main findings include a wave of spi

Pengjie Zhang, Hume A. Feldman, Roman Juszkiewicz, Albert Stebbins

We propose to use spatial correlations of the kinetic Sunyaev-Zeldovich (KSZ) flux as an estimator of the peculiar velocity power spectrum. In contrast with conventional techniques, our new method does not require measurements of the thermal SZ signal or the X-ray temperature. Moreover, this method has the special advantage that the expected systematic error

Michael Gill, Michele Trenti, M. Coleman Miller, Roeland van der Marel

In many theoretical scenarios it is expected that intermediate-mass black holes (IMBHs, with masses M ~ 100-10000 solar masses) reside at the centers of some globular clusters. However, observational evidence for their existence is limited. Several previous numerical investigations have focused on the impact of an IMBH on the cluster dynamics or brightness p

Pieter Buyle, Sven De Rijcke, Victor P. Debattista, Ignacio Ferreras

The presence of black holes (BHs) at the centers of dwarf elliptical galaxies (dEs) has been argued both theoretically and observationally. Using archival HST/WFPC2 data, we found the Virgo cluster dwarf elliptical galaxy VCC128 to harbor a binary nucleus, a feature that is usually interpreted as the observable signature of a stellar disk orbiting a central

D. Grumiller, R. Jackiw, N. Johansson

Wolfgang Kummer was a pioneer of two-dimensional gravity and a strong advocate of the first order formulation in terms of Cartan variables. In the present work we apply Wolfgang Kummer&#39;s philosophy, the `Vienna School approach&#39;, to a specific three-dimensional model of gravity, cosmological topologically massive gravity at the chiral point. Exploitin

Nicolas Puech, Serge Mora, Vincent Testard, Grégoire Porte

Model microemulsion networks of oil droplets stabilized by non ionic surfactant and telechelic polymer C18-PEO(10k)-C18 have been studied for two droplet-to-polymer size ratios. The rheological properties of the networks have been measured as a function of network connectivity and can be described in terms of simple percolation laws. The network structure ha

Valerio Ramos-Batista, Frank Baginski

In this paper we show how to bypass the usual difficulties in the analysis of elliptic integrals that arise when solving period problems for minimal surfaces. The method consists of replacing period problems with ordinary Sturm-Liouville problems involving the support function. We give a practical application by proving existence of the sheared Scherk-Karche

Alfons I. Ooms

Let U(L) be the enveloping algebra of a finite dimensional Lie algebra L over a field k of characteristic zero, Z(U(L)) its center and Sz(U(L)) its semicenter. A sufficient condition is given in order for Sz(U(L)) to be a polynomial algebra over k. Surprisingly, this condition holds for many Lie algebras, especially among those for which the radical is nilpo

Stephan Hachinger, Paolo A. Mazzali, Masaomi Tanaka, Wolfgang Hillebrandt

SNe Ia are good distance indicators because the shape of their light curves, which can be measured independently of distance, varies smoothly with luminosity. This suggests that SNe Ia are a single family of events. Similar correlations are observed between luminosity and spectral properties. In particular, the ratio of the strengths of the SiII λ5972 and λ6

Mathieu Cossutta

We study the question of the growth of Betti numbers of certain arithmetic varieties in tower of congruence coverings. In fact, our results are about Siegel varieties and varieties associated to orthogonal groups. We explain how a theorem of Waldspurger can be used to obtain lower and upper bound. Our results are in the direction of conjectures made by Sarna

F. Pauly, J. K. Viljas, U. Huniar, M. Hafner

We present a cluster-based density-functional approach to model charge transport through molecular and atomic contacts. The electronic structure of the contacts is determined in the framework of density functional theory, and the parameters needed to describe transport are extracted from finite clusters. A similar procedure, restricted to nearest-neighbor in

P. D. Nation, M. P. Blencowe, E. Buks

We carry out a quantum analysis of a dc SQUID mechanical displacement detector, comprising a SQUID with mechanically compliant loop segment, which is embedded in a microwave transmission line resonator. The SQUID is approximated as a nonlinear, current dependent inductance, inducing an external flux tunable, nonlinear Duffing self-interaction term in the mic

Andrey Pereverzev, Eric R. Bittner

It is well known that the Gaussian wave packet dynamics can be written in terms of Hamilton equations in the extended phase space that is twice as large as in the corresponding classical system. We construct several generalizations of this approach that include non-Gausssian wave packets. These generalizations lead to the further extension of the phase space