November 2005 arXiv papers — page 22

S. Komossa, W. Voges, H. -M. Adorf, D. Xu

We report identification of the radio loud narrow-line quasar SDSS J172206.03+565451.6 which we found in the course of a search for radio loud narrow-line Active Galactic Nuclei (AGN). SDSSJ172206.03+565451.6 is only the ~4th securely identified radio loud narrow-line quasar and the second-most radio loudest with a radio index R_1.4 ~ 100-700. Its black hole

Patrizia A. Caraveo

Combining resolved spectroscopy with deep imaging, XMM-Newton is providing new insights on the particle acceleration processes long known to be at work in the magnetospheres of isolated neutron stars. According to a standard theoretical interpretation, in neutron stars' magnetospheres particles are accelerated along the B field lines and, depending on th

Lisa M. Winter, Richard F. Mushotzky, Christopher S. Reynolds

We determined oxygen and iron abundances of the interstellar medium (ISM) using K-shell (O) and L-shell (Fe) X-ray photo-ionization edges towards Ultra luminous X-ray sources (ULXs). We determine the hydrogen column densities (n_H) towards the ULXs from XMM-Newton archival spectra of 14 ULX sources. We compare our X-ray values with those obtained from radio

G. Bergond, S. E. Zepf, A. J. Romanowsky, R. M. Sharples

We present wide-field spectroscopy of globular clusters around the Leo I group galaxies NGC 3379 and NGC 3384 using the FLAMES multi-fibre instrument at the VLT. We obtain accurate radial velocities for 42 globular clusters (GCs) in total, 30 for GCs around the elliptical NGC 3379, eight around the lenticular NGC 3384, and four which may be associated with e

E. Antonello, L. Mantegazza, M. Rainer, A. Miglio

A survey for line profile variability in early A-type stars has been performed in order to detect nonradial pulsation signatures. The star HR 6139, with spectral type A2V and estimated T_eff=8800 K, shows evident line profile variations that can be explained by oscillations in prograde g-modes. This feature and the known photometric variability are similar t

D. Pellicciotta, F. Frontera, G. Loffredo, A. Pisa

Results of reflectivity measurements of mosaic crystal samples of Cu (111) are reported. These tests were performed in the context of a feasibility study of a hard X-ray focusing telescope for space astronomy with energy passband from 60 to 600 keV. The technique envisaged is that of using mosaic crystals in transmission configuration that diffract X-rays fo

Jose M. Rozas, Jordi Miralda-Escude, Eduard Salvador-Sole

We estimate the maximum contribution to reionization from the first generation of massive stars, with zero metallicity, under the assumption that one of these stars forms with a fixed mass in every collapsed halo in which metal-free gas is able to cool. We assume that any halo that has already had stars previously formed in one of their halo progenitors will

J. T. Schmelz, P. C. H. Martens

The observations from 1998 April 20 taken with the Coronal Diagnostics Spectrometer CDS on SOHO of a coronal loop on the limb have shown that the plasma was multi-thermal along each line of sight investigated, both before and after background subtraction. The latter result relied on Emission Measure Loci plots, but in this Letter, we used a forward folding t

Andrew King, Rudy Wijnands

Recent X-ray observations have detected a class of very faint X-ray transients in the Galaxy which probably reveal a previously unrecognised type of accretion on to neutron stars or black holes. We show that these systems cannot have descended from binaries with stellar-mass components of normal composition. Accretion of hydrogen-depleted matter on to stella

Paulo M. Sá, Brigitte Tomé

We discuss the role of differential rotation in the evolution of the l=2 r-mode instability of a newly born, hot, rapidly-rotating neutron star. It is shown that the amplitude of the r-mode saturates in a natural way at a value that depends on the amount of differential rotation at the time the instability becomes active. It is also shown that, independently

D. K. Aitken, J. H. Hough, A. Chrysostomou

The 3.1 micron absorption feature of water-ice has been observed spectroscopically in many molecular clouds and, when it has been observed spectropolarimetrically, usually a corre- sponding polarization feature is seen. Typically on these occasions, and particularly for the BN object, a distinct position angle shift between the feature and continuum is seen,

Markus Ahlers

The origin and chemical composition of ultra high energy cosmic rays is still an open question in astroparticle physics. The observed large-scale isotropy and also direct composition measurements can be interpreted as an extragalactic proton dominance above the ankle at about 10^10 GeV. Photopion production of extragalactic protons in the cosmic microwave ba

G. Fabbiano

Today's sensitive, high-resolution X-ray observations allow the study of populations of X-ray sources, in the luminosity range of Galactic X-ray binaries, in galaxies as distant as 20-30 Mpc. The traditional astronomical tools of photometric diagrams and luminosity functions are now applied to these populations, providing a direct probe of the evolved bi

J. -U. Pott, A. Eckart, M. Krips, L. Tacconi-Garman

We present the results of a recently conducted mm-experiment at the IRAM 30m telescope. We searched in two QSO hosts for the HCN(J=1-0) line emission tracing the dense regions of gas. Our goal is to probe the HCN-CO line ratio in QSO hosts for the first time and to compare the results with recent findings of quiescent galaxies. These findings indicate a stro

E. Giacani, N. Loiseau, G. Dubner, M. J. S. Smith

We report on new VLA radio and XMM-Newton X-ray observations of the SNR G352.7-0.1. These high sensitivity, high resolution data reveal that G352.7-0.1 belongs to the thermal composite morphological class. Small scale structures in radio and X-ray emission are not always correlated and are different for the different X-rays bands examined. The distance to G3

M. A. T. Groenewegen

With the advent of space missions, like SPITZER and ASTRO-F, with sensitive detectors in the near- and mid-infra red covering a reasonable field-of-view and having a good spatial resolution, it will be possible to detect individual AGB stars in Local Group galaxies. The filters used by these missions are non-standard and different from mission to mission. In

German Olivares, Fernando Atrio-Barandela, Diego Pavon

We determine the range of parameter space of an interacting quintessence (IQ) model that best fits the luminosity distance of type Ia supernovae data and the recent WMAP measurements of Cosmic Microwave Background temperature anisotropies. Models in which quintessence decays into dark matter provide a clean explanation for the coincidence problem. We focus o

S. S. Hasan, J. -P. Zahn, J. Christensen-Dalsgaard

We suggest that high-order g modes can be used as a probe of the internal magnetic field of SPB (slowly pulsating B) stars. The idea is based on earlier work by the authors which analytically investigated the effect of a vertical magnetic field on p and g modes in a plane-parallel isothermal stratified atmosphere. It was found that even a weak field can sign

Masaru Ajiki, Yasuhiro Shioya, Yoshiaki Taniguchi, Takashi Murayama

We discuss observational properties of strong emission-line galaxies at low redshift found by our deep imaging survey for high-redshift Ly alpha emitters. In our surveys, we used the narrowband filter, NB816 (lambda_center=8150A with FWHM = 120A), and the intermediate-band filter, IA827 (lambda_center = 8270A with FWHM = 340A). In this survey, 62 NB816-exces

J. D. Vergados, Y. Giomataris

Supernova neutrinos can easily be detected by a spherical gaseous TPC detector measuring very low energy nuclear recoils. The expected rates are quite large for a neutron rich target since the neutrino nucleus neutral current interaction yields a coherent contribution of all neutrons. As a matter of fact for a typical supernova at 10 kpc, about 1000 events a

The Tibet AS Gamma Collaboration, M. Amenomori

A hybrid experiment consisting of emulsion chambers, burst detectors and the Tibet II air-shower array was carried out at Yangbajing (4,300 m a.s.l., 606 g/cm$^2$) in Tibet to obtain the energy spectra of primary protons and heliums. From three-year operation, these energy spectra are deduced between $10^{15}$ and $10^{16}$ eV by triggering the air showers a

Michael L. Norman

We review the theory of the formation of galaxy clusters and discuss their role as cosmological probes. We begin with the standard cosmological framework where we discuss the origin of the CDM matter power spectrum and the growth of density fluctuations in the linear regime. We then summarize the spherical top-hat model for the nonlinear growth of fluctuatio

Pavel A. Belov, Mario G. Silveirinha

The restrictions on the resolution of transmission devices formed by wire media (arrays of conductive cylinders) recently proposed in [Phys. Rev. B, 71, 193105 (2005)] and experimentally tested in [Phys. Rev. B, 73, 033108 (2006)] are studied in this paper using both analytical and numerical modeling. It is demonstrated that such transmission devices have su

Ke Liu, Nael Abu-Ghazaleh

Geographical routing protocols have several desirable features for use in ad hoc and sensor networks but are susceptible to voids and localization errors. Virtual coordinate systems are an alternative solution to geographically based routing protocols that works by overlaying a coordinate system on the sensors relative to well chosen reference points. VC is

Frederic P. Schuller, Mattias N. R. Wohlfarth

String backgrounds and D-branes do not possess the structure of Lorentzian manifolds, but that of manifolds with area metric. Area metric geometry is a true generalization of metric geometry, which in particular may accommodate a B-field. While an area metric does not determine a connection, we identify the appropriate differential geometric structure which

Sean Hallgren, Martin Roetteler, Pranab Sen

It has been known for some time that graph isomorphism reduces to the hidden subgroup problem (HSP). What is more, most exponential speedups in quantum computation are obtained by solving instances of the HSP. A common feature of the resulting algorithms is the use of quantum coset states, which encode the hidden subgroup. An open question has been how hard

Adam S. Bolton, Scott Burles, Leon V. E. Koopmans, Tommaso Treu

The Sloan Lens ACS (SLACS) Survey is an efficient Hubble Space Telescope Snapshot imaging survey for new galaxy-scale strong gravitational lenses. The targeted lens candidates are selected spectroscopically from within the Sloan Digital Sky Survey (SDSS) database of galaxy spectra for having multiple nebular emission lines at a redshift significantly higher

Jingwen Wu, Neal J. Evans, Yu Gao, Philip M. Solomon

Observations have revealed prodigious amounts of star formation in starburst galaxies as traced by dust and molecular emission, even at large redshifts. Recent work shows that for both nearby spiral galaxies and distant starbursts, the global star formation rate, as indicated by the infrared luminosity, has a tight and almost linear correlation with the amou

Michael Goldstein, Wilhelm Schlag

We consider one-dimensional difference Schroedinger equations on the discrete line with a potential generated by evaluating a real-analytic potential function V(x) on the one-dimensional torus along an orbit of the shift x-->x+nw. If the Lyapunov exponent is positive for all energies and w, then the integrated density of states is absolutely continuous for a

V. Malafaia, M. T. Pena, Ch. Elster, J. Adam

The S-matrix approach is used to calculate charged as well as neutral pion production reactions from NN scattering, with the same set of underlying processes and interactions. The chiral perturbation theory piN scattering amplitude is used. For the nucleon-nucleon distortions a newly developed realistic potential within the Bonn family of potentials, valid w

Ivan S. Nikolaev, Peter Lodahl, A. Floris van Driel, A. Femius Koenderink

We observe experimentally that ensembles of quantum dots in three-dimensional (3D) photonic crystals reveal strongly nonexponential time-resolved emission. These complex emission decay curves are analyzed with a continuous distribution of decay rates. The log-normal distribution describes the decays well for all studied lattice parameters. The distribution w

Kaifu Luo, Ilkka Huopaniemi, Tapio Ala-Nissila, See-Chen Ying

We investigate the dynamics of polymer translocation through a nanopore under an externally applied field using the 2D fluctuating bond model with single-segment Monte Carlo moves. We concentrate on the influence of the field strength $E$, length of the chain $N$, and length of the pore $L$ on forced translocation. As our main result, we find a crossover sca

Frederique Clement, Jean-Pierre Francoise

We propose a mathematical model allowing for the alternating pulse and surge pattern of GnRH (Gonadotropin Releasing Hormone) secretion. The model is based on the coupling between two systems running on different time scales. The faster system corresponds to the average activity of GnRH neurons, while the slower one corresponds to the average activity of reg

M. Revnivtsev, S. Sazonov, E. Churazov, S. Trudolyubov

Based on RXTE scans and observations with the SWIFT/XRT telescope and INTEGRAL observatory, we report the identification of four X-ray sources discovered during the RXTE Slew Survey of the |b|>10deg sky with nearby (z ~ 0.017-0.098) luminous (log L_2-10keV ~ 42.7-44 erg/s) active galactic nuclei. Two of the objects exhibit heavily intrinsically absorbed X-ra

D. Pal, L. DeBeer-Schmitt, T. Bera, R. Cubitt

Using small-angle neutron scattering we have measured the misalignment between an applied field of 4 kOe and the flux-line lattice in MgB$_2$, as the field is rotated away from the c axis by an angle $θ$. The measurements, performed at 4.9 K, showed the vortices canting towards the c axis for all field orientations. Using a two-band/two-gap model to calculat

Gui-Jun Ding, Rong-Gang Ping, Mu-Lin Yan

The X(1835) has been treated as a baryonium with sizable gluon content, and to be almost flavor singlet. This picture allows us to rationally understand X(1835) production in $J/ψ$ radiative decays, and its large couplings with $p\bar{p}$, $η^{\prime}ππ$. The processes $Υ(1S)\to γX(1835)$ and $J/ψ\to ωX(1835)$ have been examined. It has been found that $Br(Υ

M. Heyer, J. Williams, C. Brunt

The role of turbulent fragmentation in regulating the efficiency of star formation in interstellar clouds is examined from new wide field imaging of 12CO and 13CO J=1-0 emission from the Rosette and G216-2.5 molecular clouds. The Rosette molecular cloud is a typical star forming giant molecular cloud and G215-2.5 is a massive molecular cloud with no OB stars

Bin Zhu

Given a symmetrizable generalized Cartan matrix $A$, for any index $k$, one can define an automorphism associated with $A,$ of the field $\mathbf{Q}(u_1, >..., u_n)$ of rational functions of $n$ independent indeterminates $u_1,..., u_n.$ It is an isomorphism between two cluster algebras associated to the matrix $A$ (see section 4 for precise meaning). When $

Boris L. Granovsky

We establish necessary and sufficient conditions for convergence (in the sense of finite dimensional distributions) of multiplicative measures on the set of partitions. We show that this convergence is equivalent to asymptotic independence of finite sizes of components. The multiplicative measures depict component spectra of random structures, the equilibriu

Alex Degtyarev

We study complex plane projective sextic curves with simple singularities up to equisingular deformations. It is shown that two such curves are deformation equivalent if and only if the corresponding pairs are diffeomorphic. A way to enumerate all deformation classes is outlined, and a few examples are considered, including classical Zariski pairs.

V. P. Goncalves, M. V. T. Machado

In this letter we study the photoproduction of heavy quarks and vector mesons in the coherent proton-nucleus (pA) interactions for RHIC and LHC energies and analyze if these processes can be used to determine the QCD dynamics at high energies. The integrated cross section and rapidity distribution are estimated using the Color Glass Condensate (CGC) formalis

Shi-Hua Ouyang, Chi-Hang Lam, J. Q. You

We have studied the dissipative dynamics of a solid-state qubit with an extra electron confined to either one of two coupled quantum dots. Previous theoretical work based on Bloch-type rate equations gave an unphysical uniform occupation probability of the electron in the quantum dots even for non-identical dots. We show that this is due to neglecting higher

Marian Ioan Munteanu

In this paper we study a Riemanian metric on the tangent bundle $T(M)$ of a Riemannian manifold $M$ which generalizes Sasaki metric and Cheeger Gromoll metric and a compatible almost complex structure which together with the metric confers to $T(M)$ a structure of locally conformal almost Kählerian manifold. This is the natural generalization of the well kno

C. Bruegger, F. Kaempfer, M. Pepe, U. -J. Wiese

The long-range forces between holes in an antiferromagnet are due to magnon exchange. The one-magnon exchange potential between two holes is proportional to cos(2ϕ)/r^2 where r is the distance vector of the holes and ϕis the angle between r and an axis of the square crystal lattice. One-magnon exchange leads to bound states of holes with antiparallel spins r

Rie Kuriki Maegawa

The author comments on [1]. One of the deformed actions can express the Neveu-Schwarz-Ramond superstring under three gauge conditions. One of these depends on a matrix induced by the string coordinate.

C. D'Helon, M. R. James

This paper concerns the problem of stability for quantum feedback networks. We demonstrate in the context of quantum optics how stability of quantum feedback networks can be guaranteed using only simple gain inequalities for network components and algebraic relationships determined by the network. Quantum feedback networks are shown to be stable if the loop

Fritz Gesztesy, Yuri Latushkin, Marius Mitrea, Maxim Zinchenko

We study various spectral theoretic aspects of non-self-adjoint operators. Specifically, we consider a class of factorable non-self-adjoint perturbations of a given unperturbed non-self-adjoint operator and provide an in-depth study of a variant of the Birman-Schwinger principle as well as local and global Weinstein-Aronszajn formulas. Our applications inclu

Ping Dong, Zheng-Yuan Xue, Ming Yang, Zhuo-Liang Cao

We propose two schemes for the generation of the cluster states. One is based on cavity quantum electrodynamics (QED) techniques. The scheme only requires resonant interactions between two atoms and a single-mode cavity. The interaction time is very short, which is important in view of decoherence. Furthermore, we also discuss the cavity decay and atomic spo

R. Auzzi, M. Shifman, A. Yung

Composite non-Abelian vortices in N=2 supersymmetric U(2) SQCD are investigated. The internal moduli space of an elementary non-Abelian vortex is CP^1. In this paper we find a composite state of two coincident non-Abelian vortices explicitly solving the first order BPS equations. Topology of the internal moduli space T is determined in terms of a discrete qu

Cristopher Moore, Alexander Russell

We establish a general method for proving bounds on the information that can be extracted via arbitrary entangled measurements on tensor products of hidden subgroup coset states. When applied to the symmetric group, the method yields an Omega(n log n) lower bound on the number of coset states over which we must perform an entangled measurement in order to ob

Simone Severini

The Schmidt measure was introduced by Eisert and Briegel for quantifying the degree of entanglement of multipartite quantum systems [Phys. Rev. A 64, 022306 (2001)]. Although generally intractable, it turns out that there is a bound on the Schmidt measure for two-colorable graph states [Phys. Rev. A 69, 062311 (2004)]. For these states, the Schmidt measure i

Wolfgang Mauerer

We present the quantum programming language cQPL which is an extended version of QPL [P. Selinger, Math. Struct. in Comp. Sci. 14(4):527-586, 2004]. It is capable of quantum communication and it can be used to formulate all possible quantum algorithms. Additionally, it possesses a denotational semantics based on a partial order of superoperators and uses fix

Th. M. Nieuwenhuizen

Quantum mechanics is considered to arise from an underlying classical structure (``hidden variable theory'', ``sub-quantum mechanics''), where quantum fluctuations follow from a physical noise mechanism. The stability of the hydrogen ground state can then arise from a balance between Lorentz damping and energy absorption from the noise. Since

L. Stodolsky

A simulation of decoherence as random noise in the Hamiltonian is studied. The full Hamiltonian for the rf Squid is used, with the parameters chosen such that there is a double-potential well configuration where the two quasi-degenerate lowest levels are well separated from the rest. The results for these first two levels are in quantitative agreement with e

Alessandro Sergi

The statistical mechanics of quantum-classical systems with holonomic constraints is formulated rigorously by unifying the classical Dirac bracket and the quantum-classical bracket in matrix form. The resulting Dirac quantum-classical theory, which conserves the holonomic constraints exactly, is then used to formulate time evolution and statistical mechanics

T. Vértesi, R. Englman

Recently, Marzlin and Sanders (2004) demonstrated an inconsistency when the adiabatic approximation was applied to specific, "inverse" time-evolving systems. Following that, Tong et al. (2005) showed that the widely used traditional adiabatic conditions are insufficient to guarantee the validity of the adiabatic approximation for this class of system

Giuseppe Bimonte, Detlef Born, Enrico Calloni, Giampiero Esposito

Aladin2 is an experiment devoted to the first measurement of variations of Casimir energy in a rigid cavity. The main scientific motivation relies on the possibility of the first demonstration of a phase transition influenced by vacuum fluctuations. The guiding principle of the measurement, based on the behaviour of the critical field for an in-cavity superc

Simon Saunders

The concept of classical indistinguishability is analyzed and defended against a number of well-known criticisms, with particular attention to the Gibbs' paradox. Granted that it is as much at home in classical as in quantum statistical mechanics, the question arises as to why indistinguishability, in quantum mechanics but not in classical mechanics, for

S. Knysh, V. N. Smelyanskiy

We propose an approach suitable for solving NP-complete problems via adiabatic quantum computation with an architecture based on a lattice of interacting spins (qubits) driven by locally adjustable effective magnetic fields. Interactions between qubits are assumed constant and instance-independent, programming is done only by changing local magnetic fields.

L Zhou, M. Suhail Zubairy, Marlan O. Scully

This paper had been withdrawed

B. Bellomo, G. Compagno, F. Petruccione

We consider a free charged particle interacting with an electromagnetic bath at zero temperature. The dipole approximation is used to treat the bath wavelengths larger than the width of the particle wave packet. The effect of these wavelengths is described then by a linear Hamiltonian whose form is analogous to phenomenological Hamiltonians previously adopte

Lev Prokhorov

It is shown that for "ideal" macroscopic objects there are superselection rules forbidding superpositions of macroscopically distinguishable states of the objects. For real macroscopic bodies the notion of "weak" superselection rules is introduced. Some other aspects of the measurement problem are discussed.

L. Giuggioli, G. Abramson, V. M. Kenkre, R. R. Parmenter

A theory is provided for the estimation of home ranges of animals from the standard mark-recapture technique in which data are collected by capturing, tagging and recapturing the animals. The theoretical tool used is the Fokker-Planck equation, its characteristic quantities being the diffusion constant which describes the motion of the animals, and the attra

L. Giuggioli, G. Abramson, V. M. Kenkre, G. Suzán

Simple random walk considerations are used to interpret rodent population data collected in Hantavirus-related investigations in Panama regarding the short-tailed cane mouse, \emph{Zygodontomys brevicauda}. The diffusion constant of mice is evaluated to be of the order of (and larger than) 200 meters squared per day. The investigation also shows that the rod

V. M. Kenkre, L. Giuggioli, G. Abramson, G. Camelo-Neto

A generalized model of the spread of the Hantavirus in mice populations is presented on the basis of recent observational findings concerning the movement characteristics of the mice that carry the infection. The factual information behind the generalization is based on mark-recapture observations reported in Giuggioli et al. [Bull. Math. Biol. 67, 1135 (200

Yuval Tabach, Michael Milyavsky, Igor Shats, Ran Brosh

Deciphering regulatory events that drive malignant transformation represents a major challenge for systems biology. Here we analyzed genome-wide transcription profiling of an in-vitro transformation process. We focused on a cluster of genes whose expression levels increased as a function of p53 and p16INK4A tumor suppressors inactivation. This cluster predom

Joseph Lotem, Dvir Netanely, Eytan Domany, Leo Sachs

We have analyzed gene expression data from 3 different kinds of samples: normal human tissues, human cancer cell lines and leukemic cells from lymphoid and myeloid leukemia pediatric patients. We have searched for genes that are over expressed in human cancer and also show specific patterns of tissue-dependent expression in normal tissues. Using the expressi

Joseph Lotem, Hila Benjamin, Dvir Netaneli, Eytan Domany

Using DNA microarray and cluster analysis of expressed genes in a cloned line (M1-t-p53) of myeloid leukemic cells, we have analyzed the expression of genes that are preferentially expressed in different normal tissues. Clustering of 547 highly expressed genes in these leukemic cells showed 38 genes preferentially expressed in normal hematopoietic tissues an

Christophe Rosty, Michal Sheffer, Dafna Tsafrir, Nicolas Stransky

Specific HPV DNA sequences are associated with more than 90% of invasive carcinomas of the uterine cervix. Viral E6 and E7 oncogenes are key mediators in cell transformation by disrupting TP53 and RB pathways. To investigate molecular mechanisms involved in the progression of invasive cervical carcinoma, we performed a gene expression study on cases selected

G. Ruffini, C. Ray, J. Marco, L. Fuentemilla

We analyze the complex networks associated with brain electrical activity. Multichannel EEG measurements are first processed to obtain 3D voxel activations using the tomographic algorithm LORETA. Then, the correlation of the current intensity activation between voxel pairs is computed to produce a voxel cross-correlation coefficient matrix. Using several cor

Ihor Lubashevsky, Cyril Garnisov, Reinhard Mahnke, Boris Lifshits

The paper presents a preliminary analysis of traffic flow data collected in the Lefortovo tunnel located on the 3-rd circular highway of Moscow. It is shown that the observed tunnel congested traffic in fact exhibits cooperative phenomena in vehicle motion, namely, there is a region of widely scatted states on the fundamental diagrams which is related typica

Douglas Scott, J. P. Zibin

A recent paper by Hsu & Zee (physics/0510102) suggests that if a Creator wanted to leave a message for us, and she wanted it to be decipherable to all sentient beings, then she would place it on the most cosmic of all billboards, the Cosmic Microwave Background (CMB) sky. Here we point out that the spherical harmonic coefficients of the observed CMB anisotro

Luiz Fernando Roncaratti, Ricardo Gargano, Geraldo Magela e Silva

Several types of numerical and combinatorial optimization algorithms have been used as useful tools to minimize functional forms. Generally, when those forms are non-linear or occur in problems without a specific optimization method, stochastic methods based on search algorithms have shown good results due to its smaller susceptibility to be trapped in a loc

K. M. Hanna, K. V. Lukyanov, V. K. Lukyanov, Z. Metawei

The (semi-)microscopic double-folding nucleus-nucleus optical potentials are suggested for consideration of inelastic scattering with excitation of collective nuclear states by using the adiabatic approach and the elastic scattering amplitude in the high-energy approximation. The analytical expression for inelastic scattering amplitude is obtained keeping th

H. Machner, J. Niskanen

We review to what extent charge independence breaking (\emph{CIB}) in isospin related reactions of the type $NN\to dπ$ can or could be seen in existing data. In doing this we present fits to global and threshold cross sections including most recent data. Applying these we point out the probable impossibility to make model independent predictions even based s

V. K. Chandrasekar, S. N. Pandey, M. Senthilvelan, M. Lakshmanan

In this paper, we consider a generalized second order nonlinear ordinary differential equation of the form $\ddot{x}+(k_1x^q+k_2)\dot{x}+k_3x^{2q+1}+k_4x^{q+1}+λ_1x=0$, where $k_i$'s, $i=1,2,3,4$, $λ_1$ and $q$ are arbitrary parameters, which includes several physically important nonlinear oscillators such as the simple harmonic oscillator, anharmonic os

Yoshimasa Matsuno

This paper extends the results of the previous paper designated I hereafter in which the one- and two-soiton solutions of the Degasperis-Procesi(DP) equation were obtained and their peakon limit was considered. Here, we present the general N-soliton solution of the DP equation and investigate its property. We show that it has a novel structure expressed by a

Nathan Becker, J. D. Scheel, M. C. Cross, Guenter Ahlers

Experiments and simulations from a variety of sample sizes indicated that the centrifugal force significantly affects rotating Rayleigh-Bénard convection-patterns. In a large-aspect-ratio sample, we observed a hybrid state consisting of domain chaos close to the sample center, surrounded by an annulus of nearly-stationary nearly-radial rolls populated by occ

P. S. Turner, D. J. Rowe, J. Repka

For applications of group theory in quantum mechanics, one generally needs explicit matrix representations of the spectrum generating algebras that arise in bases that reduce the symmetry group of some Hamiltonian of interest. Here we use vector coherent state techniques to develop an algorithm for constructing the matrices for arbitrary finite-dimensional i

Siu A. Chin

I show that the basic structure of symplectic integrators is governed by a theorem which states {\it precisely}, how symplectic integrators with positive coefficients cannot be corrected beyond second order. All previous known results can now be derived quantitatively from this theorem. The theorem provided sharp bounds on second-order error coefficients exp

Richard Froese, David Hasler, Wolfgang Spitzer

We give a new proof of a version of Klein's theorem on the existence of absolutely continuous spectrum for the Anderson model on the Bethe Lattice at weak disorder.

Kathleen L. Petersen, Christopher D. Sinclair

We study the geometry, topology and Lebesgue measure of the set of monic conjugate reciprocal polynomials of fixed degree with all roots on the unit circle. The set of such polynomials of degree N is naturally associated to a subset of $\R^{N-1}$. We calculate the volume of this set, prove the set is homeomorphic to the $N-1$ ball and that its isometry group

Žarko Mijajlović, Miloš Milošević, Aleksandar Perović

In this article a new method of generating sums of like powers is presented.

Alberto Calabri, Margarida Mendes Lopes, Rita Pardini

Numerical Campedelli surfaces are minimal surfaces of general type with p_g=0 (and so q=0) and K^2=2. Although they have been studied by several authors, their complete classification is not known. In this paper we classify numerical Campedelli surfaces with an involution, i.e. an automorphism of order 2. First we show that an involution on a numerical Campe

John R. Britnell, Jason Fulman

It is shown that a wide range of probabilities and limiting probabilities in finite classical groups have integral coefficients when expanded as a power series in 1/q. Moreover it is proved that the coefficients of the limiting probabilities in the general linear and unitary cases are equal modulo 2. The rate of stabilization of the finite dimensional coeffi

Norman E. Breslow, Jon A. Wellner

Weighted likelihood, in which one solves Horvitz-Thompson or inverse probability weighted (IPW) versions of the likelihood equations, offers a simple and robust method for fitting models to two phase stratified samples. We consider semiparametric models for which solution of infinite dimensional estimating equations leads to $\sqrt{N}$ consistent and asympto

William H. Meeks, Matthias Weber

We construct Colding-Minicozzi limit minimal laminations in open domains in $\rth$ with the singular set of $C^1$-convergence being any properly embedded $C^{1,1}$-curve. By Meeks' $C^{1,1}$-regularity theorem, the singular set of convergence of a Colding-Minicozzi limit minimal lamination ${\cal L}$ is a locally finite collection $S({\cal L})$ of $C^{1,

Carla Novelli, Gianluca Occhetta

We classify Fano fivefolds of index two which are projectivization of rank two vector bundles over four dimensional manifolds.

Robert E. Gompf

For a smooth map $f:X^4\toΣ^2$ that is locally modeled by holomorphic maps, the domain is shown to admit a symplectic structure that is symplectic on some regular fiber, if and only if $f^*[Σ]\ne0$. If so, the space of symplectic forms on $X$ that are symplectic on all fibers is nonempty and contractible. The cohomology classes of these forms vary with the m

Ivan Nourdin, Ciprian A. Tudor

Using the multiple stochastic integrals we prove an existence and uniqueness result for a linear stochastic equation driven by the fractional Brownian motion with any Hurst parameter. We study both the one parameter and two parameter cases. When the drift is zero, we show that in the one-parameter case the solution in an exponential, thus positive, function

Francesco Caravenna, Giambattista Giacomin, Lorenzo Zambotti

We consider continuous and discrete (1+1)-dimensional wetting models which undergo a localization/delocalization phase transition. Using a simple approach based on Renewal Theory we determine the precise asymptotic behavior of the partition function, from which we obtain the scaling limits of the models and an explicit construction of the infinite volume mea

Ganna Kudryavtseva, Volodymyr Mazorchuk

We study the algebraic properties of the series $\mathrm{K}_n$ of semigroups, which is inspired by \cite{Ki} and has origins in convexity theory. In particular, we describe Green's relations on $\mathrm{K}_n$, prove that there exists a faithful representation of $\mathrm{K}_n$ by $n\times n$ matrices with non-negative integer coefficients (and even expli

Elizabeth Wulcan

We compute residue currents of Bochner-Martinelli type associated with a monomial ideal $I$, by methods involving certain toric varieties. In case the variety of $I$ is the origin, we give a complete description of the annihilator of the currents in terms of the associated Newton diagram. In particular, we show that the annihilator is strictly included in $I

Fritz Gesztesy, Yuri Latushkin, Konstantin A. Makarov

The principal results of this paper consist of an intrinsic definition of the Evans function in terms of newly introduced generalized matrix-valued Jost solutions for general first-order matrix-valued differential equations on the real line, and a proof of the fact that the Evans function, a finite-dimensional determinant by construction, coincides with a mo

Fritz Gesztesy, Vadim Tkachenko

We derive necessary and sufficient conditions for a one-dimensional periodic Schrödinger (i.e., Hill) operator H=-d^2/dx^2+V in L^2(R) to be a spectral operator of scalar type. The conditions demonstrate the remarkable fact that the property of a Hill operator being a spectral operator is independent of smoothness (or even analyticity) properties of the pote

David Ellerman

The question "What is category theory" is approached by focusing on universal mapping properties and adjoint functors. Category theory organizes mathematics using morphisms that transmit structure and determination. Structures of mathematical interest are usually characterized by some universal mapping property so the general thesis is that category

Jonathan Bennett, Anthony Carbery, Michael Christ, Terence Tao

We consider the Brascamp--Lieb inequalities concerning multilinear integrals of products of functions in several dimensions. We give a complete treatment of the issues of finiteness of the constant, and of the existence and uniqueness of centred gaussian extremals. For arbitrary extremals we completely address the issue of existence, and partly address the i

Norbert Roehrl

We present a variational algorithm for solving the classical inverse Sturm-Liouville problem in one dimension when two spectra are given. All critical points of the least squares functional are at global minima, which which suggests minimization by a (conjugate) gradient descent algorithm. Numerical examples show that the resulting algorithm works quite reli

C. Casagrande

Let X be a complex, Gorenstein, Q-factorial, toric Fano variety. We prove two conjectures on the maximal Picard number of X in terms of its dimension and its pseudo-index, and characterize the boundary cases. Equivalently, we determine the maximal number of vertices of a simplicial reflexive polytope.

E. J. Beggs, S. Majid

We semiclassicalise the standard notion of differential calculus in noncommutative geometry on algebras and quantum groups. We show in the symplectic case that the infinitesimal data for a differential calculus is a symplectic connection, and interpret its curvature as lowest order nonassociativity of the exterior algebra. Semiclassicalisation of the noncomm