January 2002 arXiv papers — page 2

Amnon Aharony

Thirty years after the Liu-Fisher paper on the {\bf bicritical} and {\bf tetracritical} points in quantum lattice gases, these multicritical points continue to appear in a variety of new physical contexts. This paper reviews some recent multicritical phase diagrams, which involve e. g. high-$T_c$ superconductivity and various magnetic phases which may (or ma

P. T. Muzy, A. P. Vieira, S. R. Salinas

Using a weak-disorder scheme and real-space renormalization-group techniques, we obtain analytical results for the critical behavior of various q-state Potts models with correlated disordered exchange interactions along d1 of d spatial dimensions on hierarchical (Migdal-Kadanoff) lattices. Our results indicate qualitative differences between the cases d-d1=1

R. Krupke, F. Hennrich, H. B. Weber, D. Beckmann

Single bundles of carbon nanotubes have been selectively deposited from suspensions onto sub-micron electrodes with alternating electric fields. We explore the resulting contacts using several solvents and delineate the differences between Au and Ag as electrode materials. Alignment of the bundles between electrodes occurs at frequencies above 1 kHz. Control

A. Minguzzi, P. Vignolo, M. P. Tosi

We use boson-fermion mapping to show that the single-particle momentum distribution in a one-dimensional gas of hard point-like bosons (Tonks gas) inside a harmonic trap decays as $p^{-4}$ at large momentum $p$. The relevant integrals expressing the one-body density matrix are evaluated for small numbers of particles in a simple Monte Carlo approach to test

Evgeny N. Bulgakov, Almas. F. Sadreev

We study spin dependent electron transmission through one- and two-dimensional curved waveguides and quantum dots with account of spin-orbit interaction. We prove that for a transmission through arbitrary structure there is no spin polarization provided that electron transmits in isolated energy subband and only two leads are attached to the structure. In pa

Muneo Sugiura, Yoshikazu Suzumura

The effect of correlation on Peierls transition, which is accompanied by a dimerization, t_d, of a bond alternation for transfer energy, has been examined for a half-filled one-dimensional electron system with on-site repulsive interaction (U). By applying the renormalization group method to the interaction of the bosonized Hamiltonian, the dimerization has

Evgeniy Khain, Baruch Meerson

Symmetry-breaking instability of a laterally uniform granular cluster (strip state) in a prototypical driven granular gas is investigated. The system consists of smooth hard disks in a two-dimensional box, colliding inelastically with each other and driven, at zero gravity, by a "thermal" wall. The limit of nearly elastic particle collisions is consi

Erik Aurell, Duccio Fanelli

The non-linear evolution of one-dimensional perturbations in a three-dimensional expanding Universe is considered. A general Lagrangian scheme is derived, and compared to two previously introduced approximate models. These models are simulated with heap-based event-driven numerical procedure, that allows for the study of large systems, averaged over many rea

Michael S. Turner

A convergence of ideas, observations and technology have led to the greatest period of cosmological discovery yet. Over the past three years we have determined the basic features of our Universe. We are now challenged to make sense of what we have found. The outcome of planned experiments and observations as well as new ideas will be required. If we succeed,

Isaac Shlosman

The central kpc of barred galaxies exhibits a wealth of morphological information on different components with clear dynamical consequences. These include nuclear rings, spirals, bars, and more. We argue that this morphology is driven by large-scale stellar bars and analyze its consequences for gas dynamics and the distribution of star-forming regions. Speci

Stacy Palen, Bruce Balick, Arsen R. Hajian, Yervant Terzian

We have combined two epochs of Hubble Space Telescope WFPC2 imaging data with ground-based expansion velocities to determine distances to three planetary nebulae (NGC 6578, NGC 6884, and IC 2448). We used two variants of the expansion parallax technique--a gradient method and a magnification method--to determine the distances. The results from the two method

Martin Elvis, Massimo Marengo, Margarita Karovska

Although dust is widely found in astrophysics, forming dust is surprisingly difficult. The proper combination of low temperature (<2000 K) and high density is mainly found in the winds of late-type giant and supergiant stars which, as a result, are the most efficient sources of dust known. Dust ejected from these stars into the interstellar medium has multip

Neil J. Cornish, David N. Spergel, Charles L. Bennett

We are surrounded by radiation that originated from the big bang. It has traveled to us from the farthest reaches of the Universe, carrying with it an unaltered record of the beginning of time and space. The radiation is in the form of gravitational waves - propagating ripples in the curvature of spacetime. We describe a mission to detect these Gravitational

S. Wolf, N. V. Voshchinnikov, Th. Henning

We present the first numerical radiative transfer simulation of multiple light scattering in dust configurations containing aligned non-spherical (spheroidal) dust grains. Such models are especially important if one wants to explain the circular polarization of light, observed in a variety of astronomical objects. The radiative transfer problem is solved on

N V Voshchinnikov, V G Farafonov

Using the method of separation of variables and a new approach to calculations of the prolate spheroidal wave functions, we study the optical properties of very elongated (cigar-like) spheroidal particles. A comparison of extinction efficiency factors of prolate spheroids and infinitely long circular cylinders is made. For the normal and oblique incidence of

Rostislav Protassov, David A. van Dyk, Alanna Connors, Vinay L. Kashyap

The likelihood ratio test (LRT) and the related $F$ test, do not (even asymptotically) adhere to their nominal $χ^2$ and $F$ distributions in many statistical tests common in astrophysics, thereby casting many marginal line or source detections and non-detections into doubt. Although there are many legitimate uses of these statistics, in some important cases

A. A. Berezhnoi, B. A. Klumov

The Lunar Prospector mission detected hydrogen-containing compounds in the lunar polar regions. We have considered the comet hypothesis of the origin of polar volatiles on the Moon. In the present paper we use our model of a comet impact with photochemical processes to be included to estimate chemical composition of volatiles which can be captured by the col

Nikita Salvi, Mat J. Page, Jason A. Stevens, Keith O. Mason

IIIZw2 was observed with XMM-Newton in July 2000. Its X-ray spectrum can be described by a powerlaw of photon index Gamma = 1.7 with a Gaussian line at 6.7 keV. There is no significant evidence of intrinsic absorption within the source or of a soft X-ray excess. Multi-wavelength light curves over a period of 25 years show related variations from the radio to

P. Gandhi, A. C. Fabian, C. S. Crawford

Models for the origin of the hard X-ray background have suggested that sources with the most accretion activity lie hidden in highly obscured AGN. We report on our study of hard, serendipitous sources in the fields of Chandra clusters with fluxes close to the turn-over in the source-counts. These include two Type II quasars with measured X-ray luminosities >

Henk Hoekstra, Howard Yee, Mike Gladders

We present a variety of weak lensing results based on the ongoing analysis of R_C-band imaging data from the Red-Sequence Cluster Survey (RCS). We briefly discuss the weak lensing signal induced by intervening large scale structure (cosmic shear), and study the properties of the dark matter halos surrounding galaxies with 19.5<R_C<21 (which have a median red

David Wands

I review the standard analysis of adiabatic scalar and tensor perturbations produced by slow-roll inflation driven by a single scalar field, before going on to discuss recent work on the role of non-adiabatic modes during and after inflation. Isocurvature perturbations correlated with adiabatic modes may be produced during multi-field inflation and would giv

A. Biviano, P. Katgert, T. Thomas, C. Adami

We study luminosity and morphology segregation of over 3000 cluster galaxies in an ensemble cluster of 59 rich, nearby galaxy clusters observed in the ESO Nearby Cluster Survey (ENACS). Within this sample we identify those galaxies that are in substructures. We compare the distribution of projected clustercentric distance, R, and &#39;normalized&#39; relativ

Andreas O. Jaunsen

Here we present results from a maximum likelihood analysis of galaxy-galaxy weak lensing effects as measured in a 12.5&#39; x 12.5&#39; field obtained at the Nordic Optical Telescope, on La Palma, Spain. The analysis incorporates photometric redshifts and gives circular velocities consistent with previous weak lensing work.

R. C. North, T. R. Marsh, U. Kolb, V. S. Dhillon

Although a large number of orbital periods of cataclysmic variable stars (CVs) have been measured, comparison of period and luminosity distributions with evolutionary theory is affected by strong selection effects. A test has been discovered which is independent of these selection effects and is based upon the kinematics of CVs (Kolb & Stehle, 1996). If the

P. S. Barklem, H. C. Stempels, C. Allende Prieto, O. P. Kochukhov

An analysis of H alpha and H beta spectra in a sample of 30 cool dwarf and subgiant stars is presented using MARCS model atmospheres based on the most recent calculations of the line opacities. A detailed quantitative comparison of the solar flux spectra with model spectra shows that Balmer line profile shapes, and therefore the temperature structure in the

Liu Xiang, Carlo Stanghellini, Daniele Dallacasa, Zhang Haiyan

We present pc-scale images of ten Compact Symmetric Objects (CSO) candidates observed with the European VLBI network (EVN). Five radio sources have been observed at 1.6 GHz, and five more at 2.3/8.4 GHz, the latter subsample with the inclusion in the VLBI array of 3 antennae normally used for geodesy. These objects were selected from existing samples of GHz

Franck Delahaye, Anil K. Pradhan

The primary X-ray diagnostic lines in He-like ions are mainly excited by electron impact from the ground level to the n = 2 levels, but at high temperatures n > 2 levels are also excited. In order to describe the atomic processes more completely collision strengths are computed for OVII including for the first time all of the following: (i) relativistic fine

Anthony H. Gonzalez, Dennis Zaritsky, Risa H. Wechsler

We present the first non-local (z>0.2) measurement of the cluster-cluster spatial correlation length, using data from the Las Campanas Distant Cluster Survey (LCDCS). We measure the angular correlation function for velocity-dispersion limited subsamples of the catalog at estimated redshifts of 0.35<z_{est}<0.575, and derive spatial correlation lengths for th

M. Audard, M. Guedel, R. L. J. van der Meer

The X-ray luminous RS CVn binary system HR 1099 has been observed on several occasions in the early phases of \textit{Chandra} and \textit{XMM-Newton}. A very hot (up to 40 MK) dominant coronal plasma has been identified from the high-resolution spectroscopic data; cooler plasma is seen down to about 3 MK. We recently obtained 100 ksec in \textit{Chandra}&#3

T. Venturi, S. Bardelli, M. Zagaria, I. Prandoni

In this paper we report and discuss the results of a radio survey in the A3571 cluster complex, a structure located in the Shapley Concentration core, and formed by the three clusters A3571, A3572 and A3575. The survey was carried out simultaneously at 22 cm and 13 cm with the Australia Telescope Compact Array, and led to the detection of 124 radio sources a

A. Merloni, A. C. Fabian

We present a model for magnetic structured coronae above accretion discs. On the shortest timescales, spatially and temporally correlated coronal flares can explain X-ray temporal and spectral variability observed in Seyfert galaxies. In particular, power density spectra, flux-spectral index and flux-variance correlations are naturally accounted for by the m

Marc Audard, Manuel Guedel

The XMM-Newton Reflection Grating Spectrometer Team has obtained observations ofa large number of coronal sources of various activity levels, ages, and spectraltypes. In particular, X-ray bright RS CVn binary systems display saturated coronal emission with spectral lines characteristic of hot (10-30 MK) plasma. Furthermore, we have obtained XMM-Newton data f

Sune Toft, Jesper Rasmussen, Jesper Sommer-Larsen, Kristian Pedersen

Bolometric and 0.2-2 keV X-ray luminosities of the hot gas haloes of simulated disc galaxies have been calculated at redshift z=0. The TreeSPH simulations are fully cosmological and the sample of 44 disc galaxies span a range in characteristic circular speeds of V_c = 130-325 km/s. The galaxies have been obtained in simulations with a considerable range of p

A. Z. Gazizov, S. I. Yanush

Various implications of new, non-perturbative pomeron inspired enhancement of small-x neutrino-nucleon structure functions for high-energy neutrino astrophysics are discussed. At x larger than 10^{-5} these functions are given by perturbative QCD, while at lower x they are determined by a specific generalization of F_2^{ep}(x,Q^2) description, proposed by A.

M. O. Calvao, J. R. T de Mello Neto, I. Waga

We have run Monte Carlo simulations, for quasar clustering redshift distortions in the Two-Degree Field QSO Redshift Survey (2QZ), in order to elicit the power of redshift distortions (geometric Alcock-Paczynski and linear kinematic) to constrain the cosmological density and equation of state parameters, Omega_{m0}, Omega_{x0}, w, of a pressureless matter +

G. Ramsay, S. Zane, M. A. Jimenez-Garate, J. W. den Herder

We present spin-resolved X-ray data of the neutron star binary Her X-1. We find evidence that the Iron line at 6.4 keV originates from the same location as the blackbody X-ray component. The line width and energy varies over both the spin period and the 35 day precession period. We also find that the correlation between the soft and hard X-ray light curves v

A. Baldi, S. Molendi, A. Comastri, F. Fiore

We present the first results from an XMM-Newton serendipitous medium-deep survey, which covers nearly three square degrees. We show the log(N)-log(S) distributions for the 0.5-2, 2-10 and 5-10 keV bands, which are found to be in good agreement with previous determinations and with the predictions of XRB models. In the soft band we detect a break at fluxes ar

Xinwu Cao

We consider the power of a relativistic jet accelerated by the magnetic field of an accretion disc. It is found that the power extracted from the disc is mainly determined by the field strength and configuration of the field far from the disc. Comparing with the power extracted from a rotating black hole, we find that the jet power extracted from a disc can

Dmitri A. Uzdensky

In this paper I analyze the process of formation of thin current structures in the magnetosphere of a conducting accretion disk in response to the field-line twisting brought about by the rotation of the disk relative to the central star. I consider an axisymmetric force-free magnetically-linked star--disk configuration and investigate the expansion of the p

Andrei Gruzinov

It has been suggested that the laws of thermodynamics are violated by what we have called a convection-dominated accretion flow (or a 1/2-law accretion flow) -- an accretion flow characterized by a constant outflow of energy. We show that both the 1/2-law flow and the Bondi flow (also known as ADAF, advection dominated accretion flow) are thermodynamically a

Fabio Governato

Efforts to understand the deviation of the L--T relation from a simple scaling law valid for clusters and groups have triggered a number of interesting studies on the subject. Techniques and approaches differ widely but most works agree on the important role played by gas cooling and heating sources like AGNs and SNe. Observations set useful constraints on t

Sumanta Tewari, Sudip Chakravarty

Using a functional integral formulation, we analyze the collective modes in the $d$-density wave state. Since only discrete symmetries are broken, no massless phase mode is present. The only relevant fluctuation is the amplitude fluctuation of the order parameter, which is treated at the gaussian level above the long range order. These fluctuations give rise

Axel Krause

A proposal towards a microscopic understanding of the Bekenstein-Hawking entropy for D=4 spacetimes with event horizon is made. Since we will not rely on supersymmetry these spacetimes need not be supersymmetric. Euclidean D-branes which wrap the event horizon&#39;s boundary will play an important role. After arguing for a discretization of the Euclidean D-b

A. C. Petkou

We argue that multi-trace deformations of the boundary CFT in AdS/CFT correspondence can arise through the OPE of single-trace operators. We work out the example of a scalar field in AdS_5 with cubic self interaction. By an appropriate reparametrization of the boundary data we are able to deform the boundary CFT by a marginal operator that couples to the con

Egor Babaev

We discuss a phase diagram of two-dimentional $U(1)\times U(1)$ superconductor in the field theoretic formalizm of Ref. [17]. In particular we discuss that in the type-I case the system exhibit a quasi-neutral quasi-superfluid state.

Alexey Anisimov, Michael Dine, Michael Graesser, Scott Thomas

String and M-theory realizations of brane world supersymmetry breaking scenarios are considered in which visible sector Standard Model fields are confined on a brane, with hidden sector supersymmetry breaking isolated on a distant brane. In calculable examples with an internal manifold of any volume the Kahler potential generically contains brane--brane non-

Donald Marolf, Rafael Sorkin

We consider the question raised by Unruh and Wald of whether mirrored boxes can self-accelerate in flat spacetime (the ``self-accelerating box paradox&#39;&#39;). From the point of view of the box, which perceives the acceleration as an impressed gravitational field, this is equivalent to asking whether the box can be supported by the buoyant force arising f

Li-Sheng Tseng

We comment on the conformal boundary states of the c=1 free boson theory on a circle which do not preserve the U(1) symmetry. We construct these Virasoro boundary states at a generic radius by a simple asymmetric shift orbifold acting on the fundamental boundary states at the self-dual radius. We further calculate the boundary entropy and find that the Viras

Guo-Xin Chen, Anil K. Pradhan

New theoretical results from large-scale relativistic close coupling calculations reveal the precise effect of resonances in collisional excitation of x-ray lines of Ne-like Fe XVII. Employing the Breit-Pauli R-matrix method and a 89-level eigenfunction expansion including up to n = 4 levels shows significant resonance enhancement of the collision strengths

Aleksandr V. Pukhlikov

We prove that a smooth Fano hypersurface $V=V_M\subset{\Bbb P}^M$, $M\geq 6$, is birationally superrigid. In particular, it cannot be fibered into uniruled varieties by a non-trivial rational map and each birational map onto a minimal Fano variety of the same dimension is a biregular isomorphism. The proof is based on the method of maximal singularities comb

Ferruccio Feruglio, Alessandro Strumia, Francesco Vissani

Assuming Majorana neutrinos, we infer from oscillation data the expected values of the parameters m_{nu_e} and m_{ee} probed by beta and 0nu2beta-decay experiments. If neutrinos have a `normal hierarchy&#39; we get the 90% CL ranges |m_{ee}| = (0.7 - 4.6) meV, and discuss in which cases future experiments can test this possibility. For `inverse hierarchy&#39

E. Kiritsis, P. Anastasopoulos

The anomalous magnetic moment of the muon is evaluated in the D-brane realization of the Standard Model. It is pointed out that the massive anomalous U(1) gauge bosons predicted, give extra contributions that are compatible with current experimental data.

R. Jackiw, S. -Y. Pi

We show that the Seiberg-Witten map for a noncommutative gauge theory involves a noncommutative 1-cocycle. The cocycle condition enforces a consistency requirement, which has been previously derived.

Hans Guenter Dosch, Carlo Ewerz, Volker Schatz

We study the Odderon contribution to elastic pp and ppbar scattering at high energies. Different models for the Odderon-proton coupling are considered and their effects on the differential cross section in the dip region are investigated. We use a Regge fit by Donnachie and Landshoff as a framework and replace its Odderon contribution by the different models

U. Trittmann

We report on a test of the Maldacena conjecture. This string/field theory correspondence has interesting applications. When combined with Rehren&#39;s theorem, it has implications for issues concerning space-time structure and Lorentz symmetry. Our results indicate that the conjecture is correct. We are within 10-15% of the expected results, although the num

S. Oliver, R. G. Mann, R. Carballo, A. Franceschini

We present results from a deep mid-infrared survey of the Hubble Deep Field South (HDF-S) region performed at 7 and 15 micron with the CAM instrument on board the Infrared Space Observatory (ISO). The final map in each band was constructed by the coaddition of four independent rasters, registered using bright sources securely detected in all rasters, with th

R. G. Mann, S. Oliver, R. Carballo, A. Franceschini

We present results from a deep mid-IR survey of the Hubble Deep Field South (HDF-S) region performed at 7 and 15um with the CAM instrument on board ISO. We found reliable optical/near-IR associations for 32 of the 35 sources detected in this field by Oliver et al. (2002, Paper I): eight of them were identified as stars, one is definitely an AGN, a second see

Emmanuel Kohlprath

We compute the Schwinger term in the gravitational constraints in two dimensions, starting from the path integral in Hamiltonian form and the Einstein anomaly.

Nayantara Gupta

The number of neutrino induced upward going muons from a single Gamma Ray Burst (GRB) expected to be detected by the proposed kilometer scale IceCube detector at the South Pole location has been calculated. The effects of the Lorentz factor, total energy of the GRB emitted in neutrinos and its distance from the observer (red shift) on the number of neutrino

A. D. Dolgov, S. H. Hansen, S. Pastor, S. T. Petcov

We study three-flavor neutrino oscillations in the early universe in the presence of neutrino chemical potentials. We take into account all effects from the background medium, i.e. collisional damping, the refractive effects from charged leptons, and in particular neutrino self-interactions that synchronize the neutrino oscillations. We find that effective f

Mohsen Alishahiha, Mohammad R. Garousi

Using the recent proposal for the observables in open string field theory, we explicitly compute the coupling of closed string tachyon and massless states with the open string states up to level two. Using these couplings, we then calculate the tree level S-matrix elements of two closed string tachyons or two massless states in the open string field theory.

Richard Jozsa, Noah Linden

For any quantum algorithm operating on pure states we prove that the presence of multi-partite entanglement, with a number of parties that increases unboundedly with input size, is necessary if the quantum algorithm is to offer an exponential speed-up over classical computation. Furthermore we prove that the algorithm can be classically efficiently simulated

F. Gungor, V. I. Lahno, R. Z. Zhdanov

Group classification of a class of third-order nonlinear evolution equations generalizing KdV and mKdV equations is performed. It is shown that there are two equations admitting simple Lie algebras of dimension three. Next, we prove that there exist only four equations invariant with respect to Lie algebras having nontrivial Levi factors of dimension four an

R. A. Bertlmann, W. Grimus

We consider the time evolution of the density matrix $ρ$ in a 2-dimensional complex Hilbert space. We allow for dissipation by adding to the von Neumann equation a term $D[ρ]$, which is of Lindblad type in order to assure complete positivity of the time evolution. We present five equivalent forms of $D[ρ]$. In particular, we connect the familiar dissipation

H. Navelet, R. Peschanski

We show that, in onium-onium scattering at (very) high energy, a transition to saturation happens due to quantum fluctuations of QCD dipoles. This transition starts when the order $α^2$ correction of the dipole loop is compensated by its faster energy evolution, leading to a negative interference with the tree level amplitude. After a derivation of the the o

S. Serjeant, J. S. Dunlop, R. G. Mann, M. Rowan-Robinson

We present an extended analysis of the SCUBA observations of the Hubble Deep Field (HDF), expanding the areal coverage of the Hughes et al. 1998 study by a factor of ~1.8 and containing at least three further sources in addition to the five in that study. We also announce the public release of the reduced data products. The map is the deepest ever made in th

C. Blochinger, H. Fraas, G. Moortgat-Pick, W. Porod

We investigate selectron pair production and decay in e-e- scattering and e+e- annihilation with polarized beams taking into account neutralino mixing as well as ISR and beamstrahlung corrections. One of the main advantages of having both modes at disposal is their complementarity concerning the threshold behaviour of selectron pair production. In e-e- the c

Massimo Meneghetti, Matthias Bartelmann, Lauro Moscardini

The statistics of gravitationally lensed arcs was recognised earlier as a potentially powerful cosmological probe. However, while fully numerical models find orders of magnitude difference between the arc probabilities in different cosmological models, analytic models tend to find markedly different results. We introduce in this paper an analytic cluster len

Masako Asano, Yasuhiro Sekino

We study one-loop effective action of Berkooz-Douglas Matrix theory and obtain non-abelian action of D0-branes in the background field produced by longitudinal 5-branes. Since these 5-branes do not have D0-brane charge and are not present in BFSS Matrix theory, our analysis can be regarded as an independent test for the coupling of D-branes to general weak b

B. T. Wolschrijn, R. A. Cornelussen, R. J. C. Spreeuw, H. B. van Linden van den Heuvell

We report measurements on the guiding of cold $^{87}$Rb atoms from a magneto-optical trap by a continuous light beam over a vertical distance of 6.5 mm. For moderate laser power ($<$85 mW) we are able to capture around 40% of the cold atoms. Although the guide is red-detuned, the optical scattering rate at this detuning ($\approx$70 GHz) is acceptably low. F

Jiliang Jing

The Cardy-Verlinde formula is further verified by using the Kerr-Newman-AdS$_4$ and Kerr-Newman-dS$_4$ black holes. In the Kerr-Newman-AdS$_4$ spacetime, we find that, for strongly coupled CFTs with AdS duals, to cast the entropy of the CFT into the Cardy-Verlinde formula the Casimir energy must contains the terms $ -n ({\mathcal{J}} Ω_H+ \frac{QΦ}{2}+ \frac

Varun Sahni, Tarun Deep Saini, A. A. Starobinsky, Ujjaini Alam

We introduce a new cosmological diagnostic pair $\lbrace r,s\rbrace$ called Statefinder. The Statefinder is dimensionless and, like the Hubble and deceleration parameters $H(z)$ and $q(z)$, is constructed from the scale factor of the Universe and its derivatives only. The parameter $r(z)$ forms the next step in the hierarchy of geometrical cosmological param

Giovanni Amelino-Camelia, Dario Benedetti, Francesco D&#39;Andrea, Andrea Procaccini

We consider the two most studied proposals of relativity theories with observer-independent scales of both velocity and length/mass: the one discussed by Amelino-Camelia as illustrative example for the original proposal (gr-qc/0012051) of theories with two relativistic invariants, and an alternative more recently proposed by Magueijo and Smolin (hep-th/01120

Yosuke Uehara

We consider recently observed neutrinoless double beta decay in the context of the minimal supersymmetric standard model with R-parity violating couplings lambda^{&#39;}. We observe that most of the current experimental bounds on the R-parity violating couplings do not exclude the possibility that the neutrinoless double beta decay is caused by R-parity viol

LHPC Collaboration, SESAM Collaboration, D. Dolgov, R. Brower

Moments of the quark density, helicity, and transversity distributions are calculated in unquenched lattice QCD. Calculations of proton matrix elements of operators corresponding to these moments through the operator product expansion have been performed on $16^3 \times 32$ lattices for Wilson fermions at $β= 5.6$ using configurations from the SESAM collabor

Martin B. Einhorn

A family of SO(10) symmetric instanton solutions in Type IIB supergravity is developed. The instanton of least action is a candidate for the low-energy, semiclassical approximation to the {D=--1} brane. Unlike a previously published solution,[GGP] this admits an interpretation as a tunneling amplitude between perturbatively degenerate asymptotic states, but

Laurent Bartholdi

I describe a class of groups acting on rooted trees. The original claim was that all have intermediate word growth between polynomial and exponential. The argument constructs a functional equation on the growth formal power series, and derives the growth properties from its analytical behaviour. Unfortunately, there are substantial mistakes in the proofs, so

Mun-Seog Kim, John A. Skinta, Thomas R. Lemberger, W. N. Kang

The magnetic penetration depth, $λ^{-2}(T)$, in the basal plane of a magnesium diboride (MgB$_2$) film was measured using a two-coil mutual inductance technique at 50 kHz. This film has $T_c\simeq 38$ K, $ΔT_c \leq 1$ K, and $λ(0)\sim 1500$ Å. At low temperatures, $λ^{-2}(T)$ shows a clear exponential temperature dependence, indicating s-wave superconducting

Sanjay Gupta, R. K. P. Zia

This paper initiates the study of quantum computing within the constraints of using a polylogarithmic ($O(\log^k n), k\geq 1$) number of qubits and a polylogarithmic number of computation steps. The current research in the literature has focussed on using a polynomial number of qubits. A new mathematical model of computation called \emph{Quantum Neural Netwo

M. Nilsson, L. Levin, N. Ohlsson, T. Christiansson

In this paper initial experiments towards constructing simple quantum gates in a solid state material are presented. Instead of using specially tailored materials, the aim is to select a subset of randomly distributed ions in the material, which have the interaction necessary to control each other and therefore can be used to do quantum logic operations. The

F. Guinea, M. A. Martin-Delgado

We apply several quantization schemes to simple versions of the Chinos game. Classically, for two players with one coin each, there is a symmetric stable strategy that allows each player to win half of the times on average. A partial quantization of the game (semiclassical) allows us to find a winning strategy for the second player, but it is unstable w.r.t.

Yuri Ozhigov

We study a quantum computer with fixed and permanent interaction of diagonal type between qubits. It is controlled only by one-qubit quick transformations. It is shown how to implement Quantum Fourier Transform and to solve Shroedinger equations with linear and quadratic potentials by a quantum computer of such type. The method is adaptable to the wide range

Giuseppe Castagnoli, David Ritz Finkelstein

Systems of spin 1, such as triplet pairs of spin-1/2 fermions (like orthohydrogen nuclei) make useful three-terminal elements for quantum computation, and when interconnected by qubit equality relations are universal for quantum computation. This is an instance of quantum-statistical computation: some of the logical relations of the problem are satisfied ide

N. D. Hari Dass, Pradeep Ganesh

We have withdrawn this paper due to a fatal flaw in eqn(38).

Claus Beisbart, Martin Kerscher, Klaus Mecke

Mark correlations provide a systematic approach to look at objects both distributed in space and bearing intrinsic information, for instance on physical properties. The interplay of the objects&#39; properties (marks) with the spatial clustering is of vivid interest for many applications; are, e.g., galaxies with high luminosities more strongly clustered tha

L. N. Labzowsky, D. A. Solovyev, G. Plunien, G. Soff

The nonresonant (NR) corrections are estimated for the most accurately measured two-photon transition 1s-2s in the hydrogen atom. These corrections depend on the measurement process and set a limit for the accuracy of atomic frequency measurements. With the measurement process adopted in the modern experiments the NR contribution for 1s-2s transition energy

Yuri A. Rylov

Influence of associative delusions (AD) onto development of physics and mathematics is investigated. The associative delusion (AD) means a mistake, appearing from incorrect associations, when a property of one object is attributed to another one. Examples of most ancient delusions are: (1) connection of the gravitation field direction with a preferred direct

Shiro Tsukamoto, Markus Pristovsek, Bradford G. Orr, Akihiro Ohtake

Ga-rich GaAs (001) surfaces are successfully observed during high-temperature annealing by scanning tunneling microscopy (STM). With a substrate temperature of 550 C, reflection high-energy diffraction patterns and reflectance anisotropy spectra confirm a (4x2) Ga-stabilized surface. STM images clearly show alteration of the surface reconstructions while sca

Gy. Szondy

General Relativity is considered to be so far the best gravitation theory. However it is quite hard to use in real situations. The root of these difficulties lays in the non-linearity of the theory. Our aim was not to linearize the theory, but find the source of non-linearity and get rid of it. We found that the resolution can be obtained by defining standar

M. B. Hecht, M. Oettel, C. D. Roberts, S. M. Schmidt

Poincare' covariant Faddeev equations for the nucleon and Delta are solved to illustrate that an internally consistent description in terms of confined-quark and nonpointlike confined-diquark-correlations can be obtained. pi N-loop induced self-energy corrections to the nucleon's mass are analysed and shown to be independent of whether a pseudoscalar or pseu

Brian D. Serot

Recent progress in Lorentz-covariant quantum field theories of the nuclear many-body problem ({\em quantum hadrodynamics}, or QHD) is discussed. The importance of modern perspectives in effective field theory and density functional theory for understanding the successes of QHD is emphasized. The inclusion of hadronic electromagnetic structure and of nonanaly

H. Mineo, W. Bentz, N. Ishii, K. Yazaki

In order to extract information on the strength of quark-quark correlations in the axial vector (a.v.) diquark channel ($J^P=1^+, T=1$), we analyze the quark light cone momentum distributions in the nucleon, in particular their flavor dependencies, and the static properties of the nucleon. To construct the nucleon as a relativistic 3-quark bound state, we us

T. Kollegger

Recent results from the NA49 experiment on the energy dependence of charged kaon production in central Pb+Pb collisions are presented. First results from the new data at 80 AGeV beam energy are compared with those from lower and higher energies. A difference in the energy dependence of the <K^{+}>/<π^{+}> and <K^{-}>/<π^{-}> ratios is observed. The <K^{+}>/<

Hans Henrik Rugh

We consider the micro-canonical ensemble of a classical Hamiltonian dynamical system, the Hamiltonian being parameter dependent and in the possible presence of other first integrals. We describe a thermodynamic formalism in which a 1st law of thermodynamics, or fundamental relation, is based upon the bulk-entropy, S. Under an ergodic hypothesis, S is shown t

P. H. M. Kersten, A. S. Sorin

The N=2 supersymmetric α=1 KdV hierarchy in N=2 superspace is considered and its rich symmetry structure is uncovered. New nonpolynomial and nonlocal, bosonic and fermionic symmetries and Hamiltonians, bi-Hamiltonian structure as well as a recursion operator connecting all symmetries and Hamiltonian structures of the N=2 α=1 KdV hierarchy are constructed in

G. Sardanashvily

Solutions of a smooth first order dynamic equation can be made Lyapunov stable at will by the choice of an appropriate time-dependent Riemannian metric.

R. Gielerak, J. Damek

The problem of the Bose-Einstein condensate preservation under thermofield and standard gauge-invariant perturbations is discussed. A new result on stability of the condensate under thermofield perturbations of a polynomial type is presented.

Mark Adler Pierre van Moerbeke

The Toeplitz determinants (of increasing size) associated with the symbols $exp{t(z+z^{-1})}$ or $(1-ξ{z})^α (1-ξ{z^{-1}})^β$ satisfy recursion relations, thus expressing all the Toeplitz determinants as a rational function of the first few determinants. A. Borodin found these relations using Riemann-Hilbert methods. The nature of Borodin&#39;s relations poi

Daniela Garajeu, Annamaria Kiss

We present a method to construct a basis of singular and non-singular common eigenvectors for Gaudin Hamiltonians in a tensor product module of the Lie algebra SL(2). The subset of singular vectors is completely described by analogy with covariant differential operators. The relation between singular eigenvectors and the Bethe Ansatz is discussed. In each we

J. Torres, H. C. Rosu

We present a simple SUSY N=2 superspace extension of the differential equations in which the sought solutions are considered to be real superfields but maintaining the common derivative operators and the coefficients of the differential equations unaltered. In this way, we get selfconsistent systems of coupled differential equations for the components of the