December 2006 arXiv papers — page 42

S. Bellucci, M. Cini, P. Onorato, E. Perfetto

A theoretical analysis of the superconductivity observed recently in Carbon nanotubes is proposed. We argue that ultra-small (diameter $ \sim 0.4 nm$) single wall carbon nanotubes (with transition temperature $T_c\sim 15 ^{o}K$) and entirely end-bonded multi-walled ones ($T_c\sim 12 ^{o}K$) can superconduct by an electronic mechanism, basically the same in b

S. Bellucci, P. Onorato

We show that a nanometric four-probe ballistic junction can be used to check the presence of a transverse spin Hall current in a system with a Spin Orbit coupling not of the Rashba type, but rather due to the in-plane electric field. Indeed, the spin Hall effect is due to the presence of an effective small transverse magnetic field corresponding to the Spin

H. Schneider, Ch. Herbort, G. Jakob, H. Adrian

We report the deposition of thin Co$_2$FeSi films by RF magnetron sputtering. Epitaxial (100)-oriented and L2$_1$ ordered growth is observed for films grown on MgO(100) substrates. (110)-oriented films on Al$_2$O$_3$(110) show several epitaxial domains in the film plane. Investigation of the magnetic properties reveals a saturation magnetization of 5.0 $mu_B

Yasunori Mawatari, Kazuhiro Kajikawa

A simple analytical expression is presented for hysteretic ac loss $Q$ of a superconducting strip simultaneously exposed to an ac transport current $I_0\cosωt$ and a phase-different ac magnetic field $H_0\cos(ωt+θ_0)$. On the basis of Bean's critical state model, we calculate $Q$ for small current amplitude $I_0\ll I_c$, for small magnetic field amplitud

A. R. Pereira, A. R. Moura, W. A. Moura-Melo, D. F. Carneiro

How stable vortex-like magnetization in magnetic nanodisks with small aspect ratio ($L/R<<1$) is affected by two antidots is investigated analytically and by Monte Carlo simulations. For suitable ranges of the physical parameters this vortex presents bistable states when pinned around the antidots. The hysteresis loop obtained shows a central loop associated

W. J. Nellis

Our goals are to assist a non-practitioner understand likely resolution of the controversy about the boson that couples Cooper pairs in Cu oxides and to consider if high temperature superconductivity (HTS) in solid oxides might be related to predicted HTS in liquid metallic hydrogen (LMH) near 0 K. High temperatures (T~Tc~!D~100 K, where Tc is superconductin

Ken-Ichiro Imura, Yasuhiro Utsumi, Thierry Martin

Full counting statistics (FCS) for the transport through a molecular quantum dot magnet is studied theoretically in the incoherent tunneling regime. We consider a model describing a single-level quantum dot, magnetically coupled to an additional local spin, the latter representing the total molecular spin s. We also assume that the system is in the strong Co

Xiao-Zhong Yuan, Hsi-Sheng Goan, Ka-Di Zhu

The exact quantum dynamics of the reduced density matrix of two coupled spin qubits in a quantum Heisenberg XY spin star environment in the thermodynamic limit at arbitrarily finite temperatures is obtained using a novel operator technique. In this approach, the transformed Hamiltonian becomes effectively Jaynes-Cumming like and thus the analysis is also rel

S. Weiss, M. Thorwart, R. Egger

We study entanglement of charge qubits in a vertical tunnel-coupled double quantum dot containing two interacting electrons. Exact diagonalization is used to compute the negativity characterizing entanglement. We find that entanglement can be efficiently generated and controlled by sidegate voltages, and describe how it can be detected. For large enough tunn

Hugo Touchette, Christian Beck

We discuss a subtlety involved in the calculation of multifractal spectra when these are expressed as Legendre-Fenchel transforms of functions analogous to free energy functions. We show that the Legendre-Fenchel transform of a free energy function yields the correct multifractal spectrum only when the latter is wholly concave. If the spectrum has no definit

J. A. Eilek, F. N. Owen

We have observed a new, complete, cooling-core sample with the VLA, in order to understand how the massive black hole in the central galaxy interacts with the local cluster plasma. We find that every cooling core is currently being energized by an active radio jet, which has probably been destabilized by its interaction with the cooling core. We argue that c

P. Colin, A. Chukanov, V. Grebenyuk, D. Naumov

Most of the Ultra High Energy Cosmic Ray (UHECR) experiments and projects (HiRes, AUGER, TA, EUSO, TUS,...) use air fluorescence to detect and measure extensive air showers (EAS). The precise knowledge of the Fluorescence Light Yield (FLY) is of paramount importance for the reconstruction of UHECR. The MACFLY - Measurement of Air Cherenkov and Fluorescence L

J. H. Crossley, J. A. Eilek, T. H. Hankins

We have detected occasional, short-lived ``echoes&#39;&#39; of giant pulses from the Crab pulsar. These echo events remind us of previously reported echoes from this pulsar, but they differ significantly in detail. Our echo events last at most only a few days; the echo emission lags the primary emission by only 40-100 musec. The echoes are consistently weake

J. A. Nikkel, R. Hasty, W. H. Lippincott, D. N. McKinsey

We have measured the time dependence of scintillation light from electronic and nuclear recoils in liquid neon, finding a slow time constant of 15.4+-0.2 us. Pulse shape discrimination is investigated as a means of identifying event type in liquid neon. Finally, the nuclear recoil scintillation efficiency is measured to be 0.26+-0.03 for 387 keV nuclear reco

Jason Harris

We report on observations of the stellar populations in twelve fields spanning the region between the Magellanic Clouds, made with the Mosaic-II camera on the 4-meter telescope at the Cerro-Tololo Inter-American Observatory. The two main goals of the observations are to characterize the young stellar population (which presumably formed in situ in the Bridge

M. W. Wise, B. R. McNamara, P. E. J. Nulsen, J. C. Houck

A 227 ksec Chandra Observatory X-ray image of the hot plasma in the Hydra A cluster has revealed an extensive cavity system. The system was created by a continuous outflow or a series of bursts from the nucleus of the central galaxy over the past 200-500 Myr. The cavities have displaced 10% of the plasma within a 300 kpc radius of the central galaxy, creatin

B. F. Lane, J. L. Sokoloski, R. K. Barry, W. A. Traub

We report observations of the recurrent nova RS Oph using long-baseline near-IR interferometry. We are able to resolve emission from the nova for several weeks after the February 2006 outburst. The near-IR source initially expands to a size of approximately 5 milli-arcseconds. However, beginning around day 10 the IR source appears to begin to shrink, reachin

Suzy Collin

Black hole masses in Active Galactic Nuclei have been determined in 35 objects through reverberation mapping of the emission line region. I mention some uncertainties of the method, such as the ``scale factor&#39;&#39; relating the Virial Product to the mass, which depends on the unknown structure and dynamics of the Broad Line Region. When the black hole ma

M. Kueppers, S. Mottola, S. C. Lowry, M. F. A&#39;Hearn

Context: In 2004 asteroid (2867) Steins has been selected as a flyby target for the Rosetta mission. Determination of its spin period and the orientation of its rotation axis are essential for optimization of the flyby planning. Aim: Measurement of the rotation period and light curve of asteroid (2867) Steins at a phase angle larger than achievable from grou

S. P. Quanz, Th. Henning, J. Bouwman, H. Linz

We present Spitzer IRAC and IRS observations of the dark cloud L1287. The mid-infrared (MIR) IRAC images show deeply embedded infrared sources in the vicinity of the FU Orionis objects RNO 1B and RNO 1C suggesting their association with a small young stellar cluster. For the first time we resolve the MIR point source associated with IRAS 00338+6312 which is

Virginie Chantry, Pierre Magain

Archival HST/NICMOS-2 images of the Cloverleaf gravitational lens (H1413+117), a quadruply imaged quasar, have been analysed with a new method derived from the MCS deconvolution algorithm (Magain et al., 1998). This method is based on an iterative process which simultaneously allows to determine the Point Spread Function (PSF) and to perform a deconvolution

L. Burderi, T. Di Salvo, M. T. Menna, A. Riggio

We present a timing analysis of the 2002 outburst of the accreting millisecond pulsar SAX J1808.4-3658. A study of the phase delays of the entire pulse profile shows a behavior that is surprising and difficult to interpret: superposed to a general trend, a big jump by about 0.2 in phase is visible, starting at day 14 after the beginning of the outburst. An a

D. Blaschke, H. Grigorian

We introduce a new tool for &#39;unmasking&#39; the composition of neutron star (NS) interiors which is based on the fact that the state of matter at high densities determines the statistics of both NS observables, the temperature-age (TA) data as well as the mass distribution. We use modern cooling simulations to extract distributions of NS masses required

Alfio Bonanno, Giampiero Esposito, Claudio Rubano, Paolo Scudellaro

In the framework of renormalization-group improved cosmologies, we use the Noether symmetry approach to get exact and general integration of the matter-dominated cosmological equations. This is performed by using an expression of Lambda=Lambda(G) determined by the method itself. We also work out a comparison between such a model and the concordance LambdaCDM

N. J. Mayne, Tim Naylor, S. P. Littlefair, Eric S. Saunders

We have selected pre-main-sequence stars in 12 groups of notional ages ranging from 1 Myr to 35 Myrs, using heterogeneous membership criteria. Using these members we have constructed empirical isochrones in V, V-I colour magnitude diagrams (CMDs). This allows us to identify clearly the gap between the radiative main sequence and the convective pre-main-seque

Fiona C. Speirits, Martin A. Hendry, Alejandro Gonzalez

The desire to extend the Hubble Diagram to higher redshifts than the range of current Type Ia Supernovae observations has prompted investigation into spectral correlations in Gamma Ray Bursts, in the hope that standard candle-like properties can be identified. In this paper we discuss the potential of these new `cosmic rulers&#39; and highlight their limitat

P. Panuzzo, G. L. Granato, V. Buat, A. K. Inoue

We analyse the attenuation properties of a sample of UV selected galaxies, with the use of the spectrophotometric model Grasil. In particular, we focus on the relation between dust attenuation and the reddening in the UV spectral region. We show that a realistic modelling of geometrical distribution of dust and of the different population of stars can explai

Pierre-Henri Chavanis

We study the influence of the dimension of space on the thermodynamics of the classical and quantum self-gravitating gas. We consider Hamiltonian systems of self-gravitating particles described by the microcanonical ensemble and self-gravitating Brownian particles described by the canonical ensemble. We present a gallery of caloric curves in different dimens

Eun-Jin Kim, Nicolas Leprovost

We investigate the confinement and long-term dynamics of the magnetised solar tachocline. Starting from first principles, we derive the values of turbulent transport coefficients and then explore the implications for the confinement and long-term dynamics of the tachocline. For reasonable parameter values, the turbulent eddy viscosity is found to be negative

F. P. Pijpers

Scientific output varies between research fields and between disciplines within a field such as astrophysics. Even in fields where publication is the primary output, there is considerable variation in publication and hence in citation rates. Data from the Smithsonian/NASA Astrophysics Data System is used to illustrate this problem and argue against a &#34;on

Jan Conrad

This note gives a short review of the statistical issues concerning upper limit calculation and claiming of discovery arising in the search for exotic physics with neutrino telescopes. Low sample sizes and significant instrumental uncertainties require special consideration. Methods for treating instrumental or theoretical uncertainties in the calculation of

R. Capuzzo-Dolcetta

Different types of observations, together with consistent and physical modelizations, suggest as realistic the hypothesis of enrichement of galactic nuclei by mean of massive globular clusters orbitally decayed and merged in the inner regions of early type galaxies. In this context, the scenario of globular cluster mergers and subsequent formation of a dense

Stefan Noll, Daniele Pierini, Maurilio Pannella, Sandra Savaglio

Fundamental properties of the extinction curve, like the slope in the rest-frame UV and the presence/absence of a broad absorption excess centred at 2175A (the UV bump), are investigated for a sample of 108 massive, star-forming galaxies at 1<z<2.5, selected from the FDF Spectroscopic Survey, the K20 survey, and the GDDS. These characteristics are constraine

R. Horvat

A simple phenomenological description for the energy transfer between a variable cosmological constant (CC) and a gas of relic neutrinos in an expanding universe can account for a near coincidence between the neutrino and dark-energy densities to hold over a significant portion of the history of the universe. Although such a cosmological setup may promote ne

A. M. S. Richards, R. J. Beswick, S. T. Garrington, T. W. B. Muxlow

We use Virtual Observatory methods to investigate the association between radio and X-ray emission at high redshifts. Fifty-five of the 92 HDF(N) sources resolved by combining MERLIN+VLA data were detected by Chandra, of which 18 are hard enough and bright enough to be obscured AGN. The high-z population of microJy radio sources is dominated by starbursts an

R. J. Beswick, T. W. B. Muxlow, H. Thrall, A. M. S. Richards

We present recent and ongoing results from extremely deep 18 day MERLIN + VLA 1.4GHz observations (rms: 3.3microJy/bm) of an 8.5-by-8.5 arcminute field centred upon the Hubble Deep Field North. This area of sky has been the subject of some of the deepest observations ever made over a wide range of frequencies, from X-rays to the radio. The results presented

H. Thrall, T. W. B. Muxlow, R. J. Beswick, A. M. S. Richards

We present recent results from very deep MERLIN/VLA 1.4GHz observations of an 8.5-by-8.5 arcminute field centred on the the Hubble Deep Field North, in conjunction with BVIz catalogues of GOODS/ACS sources detected in this field. In an extension of work by Muxlow et al. (also presented at this conference) on the statistical properties of over 8000 sources, t

T. W. B. Muxlow, R. J. Beswick, H. Thrall, A. M. S Richards

Deep combination radio observations at 1.4GHz with the VLA and MERLIN have imaged a region 10 arcminutes square surrounding the Hubble Deep Field North (HDF-N). Initial studies of the weak radio source population have shown that the proportion of starburst systems increases with decreasing radio flux density with more than 70% of radio sources being starburs

O. Lardiere, F. Martinache, F. Patru

Future optical interferometric instrumentation mainly relies on the availability of an efficient cophasing system: once available, what has so far postponed the relevance of direct imaging with an interferometer will vanish. This paper focuses on the actual limits of snapshot imaging, inherent to the use of a sparse aperture: the number of telescopes and the

H. -Th. Janka, K. Langanke, A. Marek, G. Martinez-Pinedo

Advances in our understanding and the modeling of stellar core-collapse and supernova explosions over the past 15 years are reviewed, concentrating on the evolution of hydrodynamical simulations, the description of weak interactions and nuclear equation of state effects, and new insights into the nucleosynthesis occurring in the early phases of the explosion

Jaroslaw Stasielak, Slawomir Stachniewicz, Marek Kutschera

Our goal is to study the effects of the UV radiation from the first stars, quasars and hypothetical Super Heavy Dark Matter (SHDM) particle decays on the formation of primordial bound objects in the Universe. We trace the evolution of a spherically symmetric density perturbation in the Lambda Cold Dark Matter and MOND model, solving the frequency-dependent r

S. Gezari, D. C. Martin, B. Milliard, S. Basa

A supermassive black hole in the nucleus of a galaxy will be revealed when a star passes close enough to be torn apart by tidal forces and a flare of radiation is emitted by the stream of stellar debris that plunges into the black hole. Since common active galactic nuclei have accreting black holes that can also produce flares, a convincing demonstration tha

Almudena Alonso-Herrero, Jennifer L. Donley, George H. Rieke, Jane R. Rigby

We summarize multiwavelength properties of a sample of galaxies in the CDF-N and CDF-S whose Spectral Energy Distributions (SEDs) exhibit the characteristic power-law behavior expected for AGN in the Spitzer/IRAC 3.6-8micron bands. AGN selected this way tend to comprise the majority of high X-ray luminosity AGN, whereas AGN selected via other IRAC color-colo

C. Abajas, E. Mediavilla, J. A. Munoz, P. Gomez-Alvarez

The influence of microlensing in the profiles of the emission lines generated in a biconical geometry is discussed. Microlensing amplification in this anisotropic model is not directly related to the bicone&#39;s intrinsic size but depends on the orientation of the bicone axis and on the cone aperture. The orientation of the projected bicone with respect to

Jaemann Kyeong, Eon-Chang Sung, Sang Chul Kim, Sangmo Tony Sohn

We present JHK-band near-infrared photometry of star clusters in the dwarf irregular galaxy IC 5152. After excluding possible foreground stars, a number of candidate star clusters are identified in the near-infrared images of IC 5152, which include young populations. Especially, five young star clusters are identified in the (J-H, H-K) two color diagram and

J. Marvin Herndon

The high occurrence on Earth of ordinary chondrite meteorites and the making of models based upon arbitrary assumptions has led to some confusion about the origin of ordinary chondrites. Major element fractionation among chondrites has been discussed for decades as ratios relative to Si or Mg. Expressing ratios relative to Fe leads to a new relationship admi

Sperello di Serego Alighieri, Alessandro Bressan, Lucia Pozzetti

The study of the ages of early-type galaxies and their dependence on galaxy mass and environment is crucial for understanding the formation and early evolution of galaxies. We review recent works on the M/L ratio evolution, as derived from an analysis of the Fundamental Plane of early-type galaxies at z~1 both in the field and in the clusters environment. We

P. N. Bibikov

The Yang-Baxter equation for a $SU(2)\times U(1)$-symmetric $S=1/2$ spin-orbital chain was solved using the special computer algorithm developed by the author. The 8 new $R$-matrices separated on 5 groups are presented. Among the obtained integrable models there are special cases related to 1D ferromagnet ${\rm TDAE-C}_{60}$, 1D superconductors ${\rm AC}_{60

Komei Fukuda, Sonoko Moriyama, Yoshio Okamoto

Holt and Klee have recently shown that every (generic) LP orientation of the graph of a $d$-polytope satisfies a directed version of the $d$-connectivity property, i.e. there are $d$ internally disjoint directed paths from a unique source to a unique sink. We introduce two new classes HK and HK* of oriented matroids (OMs) by enforcing this property and its d

S. Zohren, R. D. Gill

We present a much simplified version of the CGLMP inequality for the 2 x 2 x d Bell scenario. Numerical maximization of the violation of this inequality over all states and measurements suggests that the optimal state is far from maximally entangled, while the best measurements are the same as conjectured best measurements for the maximally entangled state.

H. M. Khudaverdian, Th. Th. Voronov

The classical Kolmogorov-Gelfand theorem gives an embedding of a (compact Hausdorff) topological space X into the linear space of all linear functionals C(X)^* on the algebra of continuous functions C(X). The image is specified by algebraic equations: f(ab)=f(a)f(b) for all functions a, b on X; that is, the image consists of all algebra homomorphisms of C(X)

Jiri Lebl

Local conditions on boundaries of $C^\infty$ Levi-flat hypersurfaces, in case the boundary is a generic submanifold, are studied. For nontrivial real analytic boundaries we get an extension and uniqueness result, which forces the hypersurface to be real analytic. This allows us to classify all real analytic generic boundaries of Levi-flat hypersurfaces in te

E. Minguzzi

We give a causal version of Eisenhart&#39;s geodesic characterization of classical mechanics. We emphasize the geometric, coordinate independent properties needed to express Eisenhart&#39;s theorem in light of modern studies on the Bargmann structures (lightlike dimensional reduction, pp-waves). The construction of the space metric, Coriolis 1-form and scala

A. H. Fatollahi, M. Khorrami

A noncommutative space is considered the position operators of which satisfy the commutativity relations of a Lie algebra. The basic tools for calculation on this space, including the product of the fields, inner product and the proper measure for integration are derived. Some general aspects of perturbative field theory calculations on this space are also d

Gavriel Segre

Introducing his Chronology Protection Conjecture Stephen Hawking said that it seems that there exists a Chronology Protection Agency making the Universe safe for historians. Without taking sides about such a conjecture we show that the Chronology Protection Agency is not necessary in order to make the Universe unsafe for historians but safe for logicians.

Hirokazu Nishimura

Kock [Bull. Austral. Math. Soc., 25 (1982), 357-386] has considered differential forms with values in a group in a context where neighborhood relations are available. By doing so, he has made it clear where the so-called Maurer-Cartan formula should come from. In this paper, while we retain the classical definition of differential form with values in the Lie

Mei-Yu Wang, Feng-Li Yan, Ting gao, You-Cheng Li

We present a simultaneous quantum state teleportation scheme, in which receivers can not recover their quantum state separately. When they want to recover their respective quantum state, they must perform an unlocking operator together.

Tomislav Ivezic

This paper is Comment on the paper: S.A.R. Horsley and M. Babiker, Phys. Rev. Lett. 95, 010405 (2005).

Hong Li, Meng Su, Zuhui Fan, Zigao Dai

In this paper we analyze the constraints on the property of dark energy from cosmological observations. Together with SNe Ia Gold sample, WMAP, SDSS and 2dFGRS data, we include 69 long Gamma-Ray Bursts (GRBs) data in our study and perform global fitting using Markov Chain Monte Carlo (MCMC) technique. Dark energy perturbations are explicitly considered. We p

Alexander B. Balakin, Alexei E. Zayats

A self-consistent non-minimal non-Abelian Einstein-Yang-Mills model, containing three phenomenological coupling constants, is formulated. The ansatz of a vanishing Yang-Mills induction is considered as a particular case of the self-duality requirement for the gauge field. Such an ansatz is shown to allow obtaining an exact solution of the self-consistent set

Alexander B. Balakin, Alexei E. Zayats

We discuss new exact spherically symmetric static solutions to non-minimally extended Einstein-Yang-Mills equations. The obtained solution to the Yang-Mills subsystem is interpreted as a non-minimal Wu-Yang monopole solution. We focus on the analysis of two classes of the exact solutions to the gravitational field equations. Solutions of the first class belo

D. W. Shen, B. P. Xie, J. F. Zhao, L. X. Yang

Charge density wave, or CDW, is usually associated with Fermi surfaces nesting. We here report a new CDW mechanism discovered in a 2H-structured transition metal dichalcogenide, where the two essential ingredients of CDW are realized in very anomalous ways due to the strong-coupling nature of the electronic structure. Namely, the CDW gap is only partially op

Pan-Jun Kim, Tae-Wook Ko, Hawoong Jeong, Kyoung J. Lee

Chaotic itinerancy is a universal dynamical concept that describes itinerant motion among many different ordered states through chaotic transition in dynamical systems. Unlike the expectation of the prevalence of chaotic itinerancy in high-dimensional systems, we identify chaotic itinerant behavior from a relatively simple ecological system, which consists o

T. Aste, T. Di Matteo, M. Saadatfar, T. J. Senden

We have discovered an invariant distribution for local packing configurations in static granular media. This distribution holds in experiments for packing fractions covering most of the range from random loose packed to random close packed, for beads packed both in air and in water. Assuming only that there exist elementary cells in which the system volume i

Hua Xiao, Amir H. Banihashemi

A method for estimating the performance of low-density parity-check (LDPC) codes decoded by hard-decision iterative decoding algorithms on binary symmetric channels (BSC) is proposed. Based on the enumeration of the smallest weight error patterns that can not be all corrected by the decoder, this method estimates both the frame error rate (FER) and the bit e

Philip J. Humphrey, David A. Buote

We present a Chandra survey of LMXBs in 24 early-type galaxies. Correcting for detection incompleteness, the X-ray luminosity function (XLF) of each galaxy is consistent with a powerlaw with negative logarithmic differential slope, beta~2.0. However, beta strongly correlates with incompleteness, indicating the XLF flattens at low-Lx. The composite XLF is wel

Andrei Marshakov, Nikita Nekrasov

The prepotential of the effective N=2 super-Yang-Mills theory perturbed in the ultraviolet by the descendents of the single-trace chiral operators is shown to be a particular tau-function of the quasiclassical Toda hierarchy. In the case of noncommutative U(1) theory (or U(N) theory with 2N-2 fundamental hypermultiplets at the appropriate locus of the moduli

Eugene V. Stefanovich

We explore the idea that gravitational interaction can be described by instantaneous inter-particle potentials. This idea is in full accord with relativistic quantum theory. In particular, it resembles the ``dressed particle&#39;&#39; approach to quantum electrodynamics. Although the complete non-perturbative of this theory is yet unknown, one can reasonably

Daniel E. Browne

A number of elegant approaches have been developed for the identification of quantum circuits which can be efficiently simulated on a classical computer. Recently, these methods have been employed to demonstrate the classical simulability of the quantum Fourier transform (QFT). In this note, we show that one can demonstrate a number of simulability results f

Fu-Guo Deng, Hong-Yu Zhou andGui Lu Long

A circular quantum secret sharing protocol is proposed, which is useful and efficient when one of the parties of secret sharing is remote to the others who are in adjacent, especially the parties are more than three. We describe the process of this protocol and discuss its security when the quantum information carrying is polarized single photons running cir

Xi-Han Li, Chun-Yan Li, Fu-Guo Deng, Ping Zhou

We present two schemes for multiparty quantum remote secret conference in which each legitimate conferee can read out securely the secret message announced by another one, but a vicious eavesdropper can get nothing about it. The first one is based on the same key shared efficiently and securely by all the parties with Greenberger-Horne-Zeilinger (GHZ) states

Xi-Han Li, Fu-Guo Deng, Hong-Yu Zhou

We analyzed the security of the secure direct communication protocol based on secret transmitting order of particles recently proposed by Zhu, Xia, Fan, and Zhang [Phys. Rev. A 73, 022338 (2006)], and found that this scheme is insecure if an eavesdropper, say Eve, wants to steal the secret message with Trojan horse attack strategies. The vital loophole in th

Jarvist Frost

Codes were written to simulate the propagation of monochromatic light through a bare optical resonator, using a computational Fourier method to solve the Huygens-Fresnel integral. This was used, in the Fox-Li method, to find the lowest-loss eigenmodes of arbitrary cavity designs. An implicit shift `hopping&#39; method was employed to allow a series of increa

Friedrich W. Hehl

M.W.Evans tried to relate the electromagnetic field strength to the torsion of a Riemann-Cartan spacetime. We show that this ansatz is untenable for at least two reasons: (i) Geometry: Torsion is related to the (external) translation group and cannot be linked to an internal group, like the U(1) group of electrodynamics. (ii) Electrodynamics: The electromagn

Alexei Krouglov

Presented is intuitive proof of Black-Scholes formula for European call options, which is based on arbitrage and properties of lognormal distribution. Paper can help students and non-mathematicians to better understand economic concepts behind one of the biggest achievements in modern financial theory.

Scott Pratt

The equations of relativistic hydrodynamics are transformed so that steps forward in time preserves local simultaneity. In these variables, the space-time coordinates of neighboring points on the mesh are simultaneous according to co-moving observers. Aside from the time step varying as a function of the location on the mesh, the local velocity gradient and

S. Bacca, H. Arenhoevel, N. Barnea, W. Leidemann

Inclusive electron scattering off 4He is calculated exactly with a complete treatment of the final state interaction within a simple semirealistic potential model. We discuss results for both the longitudinal and the transverse response functions, at various momentum transfers. A consistent meson exchange current is implemented. Good agreement with available

C. Bisconti, G. Co&#39;, F. Arias de Saavedra

Momentum distributions, spectroscopic factors and quasi-hole wave functions of medium-heavy doubly closed shell nuclei have been calculated in the framework of the Correlated Basis Function theory, by using the Fermi hypernetted chain resummation techniques. The calculations have been done by using microscopic two-body nucleon-nucleon potentials of Argonne t

W. L. Wang, F. Huang, Z. Y. Zhang, Y. W. Yu

The structure of Omega-pi state with isospin I=1 and spin-parity J^p=3/2^- are dynamically studied in both the chiral SU(3) quark model and the extended chiral SU(3) quark model by solving a resonating group method (RGM) equation. The model parameters are taken from our previous work, which gave a satisfactory description of the energies of the baryon ground

Y. Nir-El, G. Haquin, Z. Yungreiss, M. Hass

A controlled and precise determination of the cross-sections of the fusion reactions 7Be(p,gamma)8B and 3He(4He,gamma)7Be, which play an important role in determining the solar neutrino flux, necessitates the knowledge of a precise value of the electron-capture half-life of 7Be. This half-life may depend on the material hosting the 7Be atoms via small modifi

Yves Grandati, Alain Bérard, Ferhat Menas

The Bertrand&#39;s theorem can be formulated as the solution of an inverse problem for a classical unidimensional motion. We show that the solutions of these problems, if restricted to a given class, can be obtained by solving a numerical equation. This permit a particulary compact and elegant proof of Bertrand&#39;s theorem.

Dimitris Bertsimas, Natasha Bushueva

Employing probabilistic techniques we compute best possible upper and lower bounds on the price of an option on one or two assets with continuous piecewise linear payoff function based on prices of simple call options of possibly distinct maturities and the no-arbitrage condition, but without any assumption on the price dynamics of underlying assets. We show

Andreas Eberle, Carlo Marinelli

Sequential Monte Carlo Samplers are a class of stochastic algorithms for Monte Carlo integral estimation w.r.t. probability distributions, which combine elements of Markov chain Monte Carlo methods and importance sampling/resampling schemes. We develop a stability analysis by functional inequalities for a nonlinear flow of probability measures describing the

Huai-Dong Cao, Xi-Ping Zhu

In this paper, we provide an essentially self-contained and detailed account of the fundamental works of Hamilton and the recent breakthrough of Perelman on the Ricci flow and their application to the geometrization of three-manifolds. In particular, we give a detailed exposition of a complete proof of the Poincaré conjecture due to Hamilton and Perelman.

Kirill Vankov

Shimura&#39;s conjectire (1963) concerns the rationality of the generating series for Hecke operators for the symplectic group of genus g. This conjecture wes proved by Andrianov for arbitrary genus g. For genus g=4, we explicify the rational fraction in this conjecture. Using formulas for images of double cosets, we first compute the sum of the generating s

Yuji Koike, Kazuhiro Tanaka

A dominant QCD mechanism for the single transverse-spin asymmetry in hard processes is induced by the twist-3 quark-gluon correlations inside nucleon, combined with the soft-gluonic poles to produce the interfering phase for the associated partonic hard scattering. It is shown that the corresponding interfering amplitude can be calculated entirely in terms o

Hiroyuki Kawamura, Jiro Kodaira, Kazuhiro Tanaka

We present QCD prediction of double-spin asymmetries ($A_{TT}$) in transversely polarized Drell-Yan process at small transverse momentum $Q_T$ of dimuon. Resummation of large logarithmic corrections, relevant in small $Q_T$ region, is performed up to next-to-leading logarithmic (NLL) accuracy. $A_{TT}$ at RHIC, J-PARC and GSI are studied numerically in the c

Peter N. Meisinger, Michael C. Ogilvie

We introduce a D-dimensional Hamiltonian formalism for the study of Polyakov loop models of finite temperature gauge theories in D+1 dimensions. Polyakov loop string tensions are obtained from energy eigenstates of the Hamiltonian. For D=1, the gauge theory reduces to quantum mechanics on the gauge group; for D>1, the Hamiltonian includes hopping terms that

Adilson E. Motter, Manuel A. Matias, Juergen Kurths, Edward Ott

At the eight-year anniversary of Watts & Strogatz&#39;s work on the collective dynamics of small-world networks and seven years after Barabasi & Albert&#39;s discovery of scale-free networks, the area of dynamical processes on complex networks is at the forefront of the current research on nonlinear dynamics and complex systems. This volume brings together a

F. M. Russell, J. C. Eilbeck

We report the ejection of atoms at a crystal surface caused by energetic breathers which have travelled more than 10^7 unit cells in atomic chain directions. The breathers were created by bombardment of a crystal face with heavy ions. This effect was observed at 300K in the layered crystal muscovite, which has linear chains of atoms for which the surrounding

Issai Shlimak, Israel Vagner

We suggest a new method of quantum information processing based on the precise placing of P-31 isotope atoms in a quasi-one-dimensional Si-28 nanowire using isotope engineering and neutron-transmutation doping of the grown structures. In our structure, interqubit entanglement is based on the indirect interaction of P-31 nuclear spins with electrons localized

Congxiao Liu, Min Sun, Hideo Fujiwara

Complementary nature of coercivity enhancement and exchange bias is generalized from the layered systems to ferro-antiferromagnet (F-AF) exchange coupled systems with arbitrary configurations and is proved based on the coherent rotation of the F magnetization. In the proof, the effect of F-AF coupling is absorbed into the anisotropy of the F part, resulting

Giovanni Gallavotti

A unified viewpoint is presented in margin to the ``Work, dissipation and fluctuations in nonequilibrium physics&#39;&#39;, Bruxelles 22-25 March, 2006, where the topics were discussed by various authors and it became clear the need that the very different viewpoints be consistently presented by their proponents.

G. Lavagetto, I. Bombaci, A. D&#39;Ai&#39;, I. Vidana

The recent discovery of burst oscillations at 1122 Hz in the x-ray transient XTE J1739-285, together with the measurement of the mass of the binary millisecond pulsar PSR J0751+1807 (2.1 +- 0.2 solar masses) can finally allow us to put strong, model-independent observational constraints to the equation of state of compact stars. We show that the measurement

Avi Shporer, Joel Hartman, Tsevi Mazeh, Wolfgang Pietsch

Aims: Study the high-mass X-ray binary X-7 in M33 using broad-band optical data. Methods: We used recently published CFHT r&#39; and i&#39; data for variable stars in M33 to extract the light curve of the optical counterpart of X-7. We combined these data with DIRECT B and V measurements in order to search for an independent optical modulation with the X-ray

M. Coleman Miller

With current terrestrial gravitational wave detectors working at initial design sensitivities, and upgrades and space missions planned, it is likely that in the next five to ten years gravitational radiation will be detected directly from a variety of classes of objects. The most confidently expected of these classes is compact binaries, involving neutron st

Frederick M. Goodman, Holly Hauschild Mosley

The cyclotomic Birman-Wenzl-Murakami algebras are quotients of the affine BMW algebras in which the affine generator satisfies a polynomial relation. We study admissibility conditions on the ground ring for these algebras, and show that the algebras defined over an admissible integral ground ring $S$ are free $S$--modules and isomorphic to cyclotomic Kauffma

Frederick M. Goodman, Holly Hauschild Mosley

The cyclotomic Birman-Wenzl-Murakami algebras are quotients of the affine BMW algebras in which the affine generator satisfies a polynomial relation. We show that the cyclotomic BMW algebras are free modules over any (admissible, integral) ground ring, and that they are isomorphic to cyclotomic versions of the Kauffman tangle algebras

O. Costin, S. Tanveer

We consider the Navier-Stokes initial value problem, $$v_t - \nabla v = -\mathcal{P} [ v \cdot \nabla v \right ] + f, v(x, 0) = v_0 (x), x \in \mathbb{R}^3 $$ where $\mathcal{P}$ is the Hodge-Projection to divergence free vector fields in the assumption that $ | f |_{μ, β} < \infty $ and $| v_0 |_{μ+2, β} < \infty$ for $β\ge 0, μ> 3$, where $$ | {\hat f} (k)

Murat Korunur, Mustafa Salti, Oktay Aydogdu

This paper has been removed by arXiv administrators because it plagiarizes gr-qc/0203084, gr-qc/0607138, gr-qc/0011087, gr-qc/0102070, gr-qc/0607138, gr-qc/0109017, gr-qc/0212018, and gr-qc/9409039.