arXiv papers from November 2003

Joel K. Erickson, Daniel H. Wesley, Paul J. Steinhardt, Neil Turok

We consider cosmological models with a scalar field with equation of state $w\ge 1$ that contract towards a big crunch singularity, as in recent cyclic and ekpyrotic scenarios. We show that chaotic mixmaster oscillations due to anisotropy and curvature are suppressed, and the contraction is described by a homogeneous and isotropic Friedmann equation if $w>1$

M. Plionis, S. Basilakos, H. Tovmassian

We estimate the distribution of intrinsic shapes of UZC-SSRS2 groups of galaxies from the distribution of their apparent shapes. We measure the projected group axial ratio using the moments of their discrete galaxy distribution. Then using the non-parametric kernel method to estimate the smooth apparent axial ratio distribution we numerically invert a set of

Alejandro Rivero

We note an intriguing coincidence in nuclear levels, that the subshells responsible for doubly magic numbers happen to bracket nuclei at the energies of the Standard Model bosons. This could show that these bosons actually contribute to the effective mesons of nuclear models.

Frank Gaitan

We examine the adiabatic dynamics of a quantum system coupled to a noisy classical control field. A stochastic phase shift is shown to arise in the off-diagonal elements of the system's density matrix which can cause decoherence. We derive the condition for onset of decoherence, and identify the noise properties that drive decoherence. We show how this decoh

C. S. Botzler, J. Snigula, R. Bender, U. Hopp

We present a modified version of the friends-of-friends (FOF) structure finding algorithm, designed specifically to locate groups or clusters of galaxies in photometric redshift datasets. The main objective of this paper is to show that this extended friends-of-friends (hereafter EXT-FOF) algorithm yields results almost identical to the original FOF, if appl

Daniel Brown

An analysis is made of a moving disturbance using a directed cyclic graph. A statistical approach is used to calculate the alternative positions in space and state of the disturbance with a defined observed time. The probability for a freely moving entity interacting in a particular spatial position is calculated and a formulation is derived for the minimum

Daniel Etzold

Using naive Bayes for email classification has become very popular within the last few months. They are quite easy to implement and very efficient. In this paper we want to present empirical results of email classification using a combination of naive Bayes and k-nearest neighbor searches. Using this technique we show that the accuracy of a Bayes filter can

Jeniffer E. Parker, Roberta M. Humphreys, Timothy C. Beers

We report a kinematic signature associated with the observed asymmetry in the distribution of thick disk/inner halo stars interior to the Solar circle described in Paper I. In that paper we found a statistically significant excess (20% to 25 %) of stars in quadrant I (l ~ 20 deg to 55 deg) both above and below the plane (b ~ +/- 25 deg to +/- 45 deg) compare

Daniel Brown

A cellular automata approach using a Directed Cyclic Graph is used to model interrelationships of fluctuating time, state and space. This model predicts phenomena including a constant and maximum speed at which any moving entity can travel, time dilation effects in accordance with special relativity, calculation for the Doppler effect, propagation in three s

Julien Laurat, Thomas Coudreau, Nicolas Treps, Agnes Maitre

We study the characteristics of the quantum state of light produced by a conditional preparation protocol totally performed in the continuous variable regime. It relies on conditional measurements on quantum intensity correlated bright twin beams emitted by a non-degenerate OPO above threshold. Analytical expressions as well as computer simulations of the se

Nikola Buric, Aldo Rampioni, Giorgio Turchetti

Statistics of Poincar\' e recurrence for a class of circle maps, including sub-critical, critical, and super-critical cases, are studied. It is shown how the topological differences in the various types of the dynamics are manifested in the statistics of the return times.

Huijun Fan, Juergen Jost

We derive general Novikov-Morse type inequalities in a Conley type framework for flows carrying cocycles, therefore generalizing our results in [FJ2] derived for integral cocycle. The condition of carrying a cocycle expresses the nontriviality of integrals of that cocycle on flow lines. Gradient-like flows are distinguished from general flows carrying a cocy

Norbert A'Campo

With the help of a new program, we do computations concerning the Witten-Reshetikhin-Turaev representations of mapping class groups. In particular we distinguish some mutant fibered knots. The program can be downloaded from http://www.geometrie.ch/TQFT

Gia Dvali, Alexander Vilenkin

We study the formation of D and F-cosmic strings in D-brane annihilation after brane inflation. We show that D-string formation by quantum de Sitter fluctuations is severely suppressed, due to suppression of RR field fluctuations in compact dimensions. We discuss the resonant mechanism of production of D and F-strings, which are formed as magnetic and electr

Oliver Attie

A surgery classification theory is introduced for manifolds of bounded geometry up to quasi-isometry. The Borel conjecture for this theory is proven for flat Euclidean space.

P. Busch, T. Heinonen, P. Lahti

The operational meaning of some measures of noise and disturbance in measurements is analyzed and their limitations are pointed out. The cases of minimal noise and least disturbance are characterized.

Robert A. Herrmann

In this paper, the Eddington-Finkelstein transformation is used as an illustration of how the problem of singularities or infinities can be removed by application of nonstandard analysis to the Schwarzschild line element (metric). The evolution of a gravitationally collapsing spherical body with radius greater than but near to the Schwarzschild radius is als

Kiwoon Choi, Ian-Woo Kim

We discuss the gauge coupling renormalization in orbifold field theories in which the 4-dimensional graviton and/or matter fields are quasi-localized in extra dimension to generate hierarchically different mass scales and/or Yukawa couplings. In such theories, there can be large calculable Kaluza-Klein threshold corrections to low energy gauge couplings, enh

Robert A. Herrmann

In this paper, a simple and unified method is developed that predicts the relativistic alterations of physical measures when the behavior of a natural system is characterized by means of a specific operator equation. Separation of variables is the simple underlying procedure.

Robert A. Herrmann

In this paper, using concepts from the nonstandard physical world, the linear effect line element is derived. Previously this line element was employed to obtain, with the exception of radioactive decay, all of the experimentally verified special theory relativistic alterations in physical measures. In this paper by means of an operator equation and separati

L. Chuzhoy

Magnetic fields are generated in ionized objects rotating with respect to a radiation background. Based on conservation of canonical ion momentum, it has been previously suggested that even if the radiation intensity is unrestricted the maximum field strength generated this way is ~(10^{-4}\Omega) Gauss, where \Omega is the initial angular velocity of the ob

Ulrich Kirchner

We investigate timelike junctions (with surface layer) between spherically symmetric solutions of the Einstein-field equation. In contrast to previous investigations this is done in a coordinate system in which the junction surface motion is absorbed in the metric, while all coordinates are continuous at the junction surface. The evolution equations for all

Giovanni Amelino-Camelia

I briefly review some scenarios for the role of the Planck length in quantum gravity. In particular, I examine the differences between the schemes in which quantum gravity is expected to introduce a maximum acceleration and the schemes in which the Planck length sets the minimum value of wavelengths (maximum value of momentum). I also comment on some picture

A. V. Shytov

We study the S-matrix for the transitions at an avoided crossing of several energy levels, which is a multilevel generalization of the Landau-Zener problem. We demonstrate that, by extending the Schroedinger evolution to complex time, one can obtain an exact answer for some of the transition amplitudes. Similar to the Landau-Zener case, our result covers bot

O. P. Yushchenko, S. A. Akimenko, K. S. Belous, G. I. Britvich

The decay K- -> pi0 mu- nu has been studied using in-flight decays detected with the "ISTRA+" spectrometer. About 540K events were collected for the analysis. The lambda+ and lambda0 slope parameters of the decay form-factors f+(t), f0(t) have been measured : lambda+ = 0.0277+-0.0013 (stat)+-0.0009 (syst), lambda0 = 0.0183+-0.0011(stat)+-0.0006(syst), and d(

Nikolai Uraltsev

We analyze consequences of the approximation \mu_\pi^2 -\mu_G^2 << \mu_\pi^2 (a `BPS' limit) for B and D mesons. It is shown that neglecting perturbative effects many power corrections would vanish to all orders in 1/m_Q, in particular those violating heavy flavor symmetry. Among them are corrections to B->D formfactors. A number of relations receive correct

Claude Bardos, Francois Golse, Alex D. Gottlieb, Norbert J. Mauser

This article concerns the time-dependent Hartree-Fock (TDHF) approximation of single-particle dynamics in systems of interacting fermions. We find that the TDHF approximation is accurate when there are sufficiently many particles and the initial many-particle state is any Gibbs equilibrium state for noninteracting fermions (with Slater determinants as a spec

Nikhil J. Joshi

Gravitation lensing calculations, which are generally done for light ray, are extended to that for a massive particle. Many interesting results were observed. We discuss the scattering cross section along-with many consequential quantities here. In particular, the case of Schrwarzschild metric was taken as illustration, though the analysis applies to a wide

Jong-Phil Lee

In this talk, I introduce recently proposed method for measuring the photon polarization in $B\to K_{\rm res}\gamma$. It is also shown that anomalous right-handed top couplings can severely affect the photon polarization without spoiling the well measured branching ratio of $B\to X_s\gamma$. Estimated number of $B$ mesons needed for measuring the photon pola

Tadafumi Kishimoto, Toru Sato

Recently the so-called $\Theta^+$ resonance has been reported first from SPring8\cite{nakano} and many following experiments showed apparent confirmation of the state. Since $\Theta^+$ exclusively decays into either $K^+ n$ or $K^0 p$, it is explained as the predicted pentaquark state which includes $ u u d d \bar{s}$ quarks. However, one yet has to obtain c

O. Oron, L. P. Horwitz

We solve the problem of formulating Brownian motion in a relativistically covariant framework in 3+1 dimensions. We obtain covariant Fokker-Planck equations with (for the isotropic case) a differential operator of d'Alembert form. Treating the spacelike and timelike fluctuations separately in order to maintain the covariance property, we show that it is esse

Yukinobu Toda

Let $X$ be a smooth projective variety. We study a relationship between the derived category of $X$ and that of a canonical divisor. As an application, we will study Fourier-Mukai transforms when $\kappa (X)=dim X-1$.

H. Aoki, T. Sakakibara, H. Shishido, R. Settai

Field-angle dependent specific heat measurement has been done on the heavy-fermion superconductor CeCoIn5 down to ~ 0.29 K, in a magnetic field rotating in the tetragonal c-plane. A clear fourfold angular oscillation is observed in the specific heat with the minima (maxima) occurring along the [100] ([110]) directions. Oscillation persists down to low fields

M. Fontannaz, G. Heinrich

We analyse how the reaction gamma p -> gamma + jet + X can serve to constrain the gluon distributions. Our results are based on a code of partonic event generator type which includes full NLO corrections. We conclude that there are phase space domains in which either the gluon in the photon or the gluon in the proton give important contributions to the cross

Tetsuya Nagata, Daisuke Kato, Daisuke Baba, Shogo Nishiyama

We report on the discovery of an infrared counterpart to the X-ray transient XTE J1720-318 on 2003 January 18, nine days after an X-ray outburst, and the infrared light curve during the first 130 days after the outburst. The infrared light curve shows a decline of about 1.2 mag from the peak magnitude of Ks about 15.3 over the observation period, and a secon

A. W. P. Poon

The Sudbury Neutrino Observatory (SNO) is capable of measuring simultaneously the flux of electron-type neutrinos and the total flux of all active flavours of neutrinos originating from the Sun. A model-independent test of neutrino flavour transformation was performed by comparing these two measurements. Assuming an undistorted neutrino energy spectrum, this

Y. Harada, T. Tokushima, Y. Takata, T. Takeuchi

A recombination emission spectrum is applied to study the local lattice distortion due to core excitation in graphite. The recombination emission spectrum reveals a long low-energy tail when the C $1s$ electron is excited to the $\sigma^*$ core exciton state. This indicates a large local lattice distortion around the excited carbon atom within a core hole li

Matthias Bartelmann, Massimo Meneghetti

It was recently claimed that several galaxy clusters containing radial and tangential gravitational arcs and having a measured velocity-dispersion profile for the brightest cluster galaxy had to have central density profiles considerably flatter than those found in CDM cluster simulations. Using a simple analytic mass model, we confirm this result_for axiall

A. W. P. Poon

The Sudbury Neutrino Observatory (SNO) measures both the flux of the electron-type neutrinos and the total flux of all active flavours of neutrinos originating from the Sun. A model-independent test of neutrino flavour transformation was performed by comparing these two measurements. In 2002, this flavour transformation was definitively demonstrated. In this

L. B. Leinson, A. Perez

We argue that, in contrast to the non-relativistic approach, a relativistic evaluation of the nucleon--hole and delta-isobar--nucleon hole contributions to the pion self-energy incorporates the s-wave scattering, which requires a more accurate evaluation. Therefore relativistic approach containing only these diagrams does not describe appropriately the pion

J. Takata, S. Shibata, K. Hirtotani

We investigate the $\gamma$-ray emission from a outer-gap accelerator, which is located in the outer-magnetosphere of a pulsar. The charge depletion from the Goldreich-Julian density causes a large electric field along the magnetic field lines. The electric field accelerates electrons and positrons to high energies. We solve the formation of the electric fie

K. Garikipati, H. Narayanan, E. M. Arruda, K. Grosh

Remodelling of biological tissue, due to changes in microstructure, is treated in the continuum mechanical setting. Microstructural change is expressed as an evolution of the reference configuration. This evolution is expressed as a point-to-point map from the reference configuration to a remodelled configuration. A ``preferred'' change in configuration is c

K. Garikipati, E. M. Arruda, K. Grosh, H. Narayanan

Growth (and resorption) of biological tissue is formulated in the continuum setting. The treatment is macroscopic, rather than cellular or sub-cellular. Certain assumptions that are central to classical continuum mechanics are revisited, the theory is reformulated, and consequences for balance laws and constitutive relations are deduced. The treatment incorp

Hitoshi Murayama

Neutrino oscillation data had been a big surprise to theorists, and indeed they have ongoing impact on theory. I review what the impact has been, and what measurements will have critical impact on theory in the future.

Hendrik Heinz, Ulrich W. Suter, Epameinondas Leontidis

A new approach is introduced for calculating the spectral shifts of the most bathochromic pi -> pi* transition of an aromatic chromophore in apolar environments. As an example, perylene in solid and liquid n-alkane matrices was chosen, and all shifts are calculated relative to one well-defined solid-inclusion system. It is shown that a simple two-level treat

E. S. Sazonov, P. Klinkhachorn, R. L. Klein

The paper presents a hybrid system controller, incorporating a neural and an LQG controller. The neural controller has been optimized by genetic algorithms directly on the inverted pendulum system. The failure free optimization process stipulated a relatively small region of the asymptotic stability of the neural controller, which is concentrated around the

Harihar Behera

Gravitational Thomas Precession (GTP) is the name given to the Thomas Precession when the acceleration is caused by a gravitational force field. In continuation of our discussion on the idea of a GTP, in this note by way of considering the motion of a planet around the Sun, the GTP is shown to be a gravitomagnetic effect that a planet might experience while

Wesley Spalenza, Wander G. Ney, J. A. Helayel-Neto

In this work, we discuss the interaction between anti-symmetric rank-two tensor matter and topological Yang-Mills fields. The matter field considered here is the rank-2 Avdeev-Chizhov tensor matter field in a suitably extended $N_{T}=2$ SUSY. We start off from the $N_{T}=2$, D=4 superspace formulation and we go over to Riemannian manifolds. The matter field

Nemanja Kaloper

We show how short inflation naturally arises in a non-minimal gravity theory with a scalar field without any potential terms. This field drives inflation solely by its derivatives, which couple to the matter only through the combination $\bar g_{\mu\nu} = g_{\mu\nu} - \frac{1}{m^4} \partial_\mu \phi \partial_\nu \phi$. The theory is free of instabilities aro

Paulo D. F. Gouveia, Delfim F. M. Torres

We study Smarandache sequences of numbers, and related problems, via a Computer Algebra System. Solutions are discovered, and some conjectures presented.

Manuel Tiglio, Luis Lehner, David Neilsen

We present three-dimensional simulations of Einstein equations implementing a symmetric hyperbolic system of equations with dynamical lapse. The numerical implementation makes use of techniques that guarantee linear numerical stability for the associated initial-boundary value problem. The code is first tested with a gauge wave solution, where rather larger

Max Burke, Wieslaw Kubis, Stevo Todorcevic

We study the existence of pointwise Kadec renormings for Banach spaces of the form $C(K)$. We show in particular that such a renorming exists when $K$ is any product of compact linearly ordered spaces, extending the result for a single factor due to Haydon, Jayne, Namioka and Rogers. We show that if $C(K_1)$ has a pointwise Kadec renorming and $K_2$ belongs

A. Barresi, G. Burgio, M. Muller-Preussker

The adjoint SU(2) lattice gauge theory in 3+1 dimensions with the Wilson plaquette action modified by a Z(2) monopole suppression term is reinvestigated with special emphasis on the existence of a finite-temperature phase transition decoupling from the well-known bulk transitions.

Nickolay Y. Gnedin, Peter A. Shaver

We use cosmological simulations of reionization to predict the possible signal from the redshifted 21 cm line of neutral hydrogen in the pre-reionization era and to investigate the observability of this signal. We show that the separation of the mean (global) signal over the whole sky from the known foreground contamination may be feasible, but very challeng

A. Drago, A. Lavagno, G. Pagliara

We compute the bulk viscosity of a mixed quark-hadron phase. In the first scenario to be discussed, the mixed phase occurs at large densities and we assume that it is composed of a mixing of hyperonic matter and quarks in the Color Flavor Locked phase. In a second scenario, the mixed phase occurs at lower densities and it is composed of a mixing of nucleons

Yuri G. Prokhorov

We give some rationality constructions for Fano threefolds with canonical Gorenstein singularities.

Yuri G. Prokhorov

We consider Fano threefolds $X$ with canonical Gorenstein singularities. Under additional assumption that $X$ has at least one non-cDV point we prove a sharp bound of the degree: $-K_X^3\le 72$.

Dong Ruan

In this paper two kinds of two-boson realizations of the Higgs algebra are obtained by generalizing the well known Jordan-Schwinger realizations of the SU(2) and SU(1,1) algebras. In each kind, an unitary realization and two nonunitary realizations, together with the properties of their respective acting spaces are discussed in detail. Furthermore, similarit

D. J. Butler, D. Martinez-Delgado, W. Brandner

We present the first WFPC2 V, I photometry for the Sculptor Group galaxy NGC 300 in four fields ranging from the centre to the outer edge. We have made the first measurement of the star formation histories in two disk fields: the oldest stars were born at similar epochs and formation activity increased but at different mean rates. The main disk stellar popul

A. M. Lisewski

We approach the virtual reality phenomenon by studying its relationship to set theory, and we investigate the case where this is done using the wellfoundedness property of sets. Our hypothesis is that non-wellfounded sets (hypersets) give rise to a different quality of virtual reality than do familiar wellfounded sets. We initially provide an alternative app

Leonardo Giusti

I review recent lattice computations of the matrix element relevant for K0-K0bar mixing and discuss the advantages of fermions with an exact chiral symmetry to compute K->pipi amplitudes.

Zhi-Wei Sun

By some extremely simple arguments, we point out the following: (i) If n is the least positive k-th power non-residue modulo a positive integer m, then the greatest number of consecutive k-th power residues mod m is smaller than m/n. (ii) Let O_K be the ring of algebraic integers in a quadratic field $K=Q(\sqrt d)$ with d in {-1,-2,-3,-7,-11}. Then, for any

I. V. Burskii

In this paper we propose some approaches for finding of pointwise estimates of a solution of the Dirichlet boundary value problem $-\Delta u \pm |u|^{q-1} u = 0 $, $|u|=k$ when $|x|=d<1$ and $|u|=0$ when $|x|=1$ where $x\in \Omega = \{x| d<|x|<1\}$. Along with these we consider the same boundary conditions for the Laplace equation and get appropriate estimat

Tomohiro Inagaki, Daiji Kimura, Tsukasa Murata

We investigate an influence of an external magnetic field on chiral symmetry breaking in a four-fermion interaction model at finite temperature and chemical potential. By using the Fock-Schwinger proper-time method, we calculate the effective potential for the four-fermion interaction model at the leading order of the $1/N_c$ expansion. A phase structure of

V. E. Rochev

The problem of quantum fluctuations of the chiral condensate due to next-to-leading contributions is investigated. Meson contributions to the chiral condensate are calculated in the Nambu--Jona-Lasinio model with the analytical (dimensional) regularization in a framework of the mean-field expansion. The pion contribution can be significant, while the sigma-m

L. Pastur, M. Shcherbina

Basing on our recent results on the $1/n$-expansion in unitary invariant random matrix ensembles, known as matrix models, we prove that the local eigenvalue statistic, arising in a certain neighborhood of the edges of the support of the Density of States, is independent of the form of the potential, determining the matrix model. Our proof is applicable to th

Aleksandar Ivić

A discussion involving the evaluation of the sum $\sum_{0<\gamma\le T} |\zeta(1/2+i\gamma)|^2$ is presented, where $\gamma$ denotes imaginary parts of complex zeros of the Riemann zeta-function $\zeta(s)$. Three theorems involving certain integrals related to this sum are proved, and the sum is unconditionally shown to be $\ll T\log^2T\log\log T$.

Sergey A. Melikhov

We note that the Conway potential function $\Omega_L$ of an $m$-component link $L$, $m>1$, can be expressed as $\Omega_L(x_1,\dots,x_m)=\Theta_L(\nabla_L(x_1-x_1^{-1},\dots,x_m-x_m^{-1}))$ for a unique $\nabla_L\in\mathbb Z[z_1,\dots,z_m]$, where $\Theta_L$ is a certain endomorphism of the additive group of $\mathbb Z[x_1^{\pm1},\dots,x_m^{\pm1}]$ which depe

Harumichi Nishimura, Tomoyuki Yamakami

This paper employs a powerful argument, called an algorithmic argument, to prove lower bounds of the quantum query complexity of a multiple-block ordered search problem in which, given a block number i, we are to find a location of a target keyword in an ordered list of the i-th block. Apart from much studied polynomial and adversary methods for quantum quer

Zuo-tang Liang

Recent e+e- annihilation experiments show a striking spin alignment of vector mesons produced in the fragmentation of a polarized quark.We show that these data imply a simple relation between the polarization of the anti-quark, which is produced in the fragmentation process to combine with the fragmenting quark to form the meson, and that of the fragmenting

Takayuki Miyadera, Masanori Ohya

We investigate a quantum dynamical entropy of one-dimesional quantum spin systems. We show that the dynamical entropy is bounded from above by a quantity which is related with group velocity determined by the interaction and mean entropy of the state.

Anthony Henderson

We give a formula for the character of the representation of the symmetric group $S_n$ on each isotypic component of the cohomology of the set of regular elements of a maximal torus of $SL_n$, with respect to the action of the centre.

Ashoke Sen

We study the moduli space of the boundary conformal field theories describing an unstable D-brane of type II string theory compactified on a circle of critical radius. This moduli space has two branches, -- a three dimensional branch S^3/Z_2 and a two dimensional branch described by a square torus T^2. These two branches are joined along a circle. We compare

Yasufumi Kojima, Norihito Matsunaga, Taishi Okita

We investigate the electromagnetic fields in the vacuum exterior of a rotating relativistic star endowed with a magnetic dipole moment, and with the stellar surface behaving as a perfect conductor. While the stellar rotation is treated in the slow-approximation of general relativity, we do not restrict our attention to slowly rotating electromagnetic fields,

Chiho Matsumoto, Karen M. Leighly, Herman L. Marshall

We present results from a 50 ks observation of the narrow-line Seyfert 1 galaxy Ark 564 with the Chandra HETGS. The spectra above 2 keV are modeled by a power-law with a photon-index of 2.56+/-0.06. We confirm the presence of the soft excess below about 1.5 keV. If we fit the excess with blackbody model, the best-fit temperature is 0.124 keV. Ark 564 has bee

Paula Benaglia, Baerbel Koribalski

We present the results of radio continuum observations towards the open cluster Tr 14, where our main targets are the early-type O stars HD 93129A/B and HD 93128. The observations were carried out at 3 cm (8.64 GHz) and 6 cm (4.80 GHz) with the Australia Telescope Compact Array. Only HD 93129A (type O2 If*) was detected; we measure flux densities of S_(3cm)

Gonzalo Contreras, Fernando Oliveira

We prove that a riemannian metric on the 2-sphere or the projective plane can be C2-approximated by a smooth metric whose geodesic flow has an elliptic closed geodesic.

B. A. Gizhevskii, Yu. P. Sukhorukov, N. N. Loshkareva, A. S. Moskvin

Optical absorption spectra of nanocrystalline cupric oxide CuO samples, obtained using the converging spherical shock wave procedure, reveal significant spectral weight red-shift as compared with spectra of single crystalline CuO samples. In addition, some of these samples manifest the remarkable temperature-dependent &#34;peak-dip-hump&#34; feature near 1.3

Janusz Jedrzejewski, Taras Krokhmalskii

In the framework of the band theory, we consider two tight-binding models of insulators. The first one, proposed recently by Taraskin et al, is a translationally invariant system, built out of two independent non-overlapping bands of single-particle orbitals that are coupled by a weak inter-band hybridization. This kind of insulator exhibits unphysical prope

Hisao Hayakawa, Hiroto Kuninaka

We have reviewed recent developments of the theory of the impact for macroscopic elastic materials. This review includes (i) standard theories for the normal impact and the oblique impact, (ii) some typical approaches to simulate impact problems, (iii) and an example of our simulation to clarify the mechanism of anomalous restitution coefficient in an obliqu

B. Laburthe Tolra, K. M. O&#39;Hara, J. H. Huckans, W. D. Phillips

We investigate correlation properties of a one-dimensional interacting Bose gas by loading a magnetically trapped 87-Rb Bose-Einstein condensate into a deep two-dimensional optical lattice. We measure the three-body recombination rate for both the BEC in the magnetic trap and the BEC loaded into the optical lattice. The recombination rate coefficient is a fa

B. G. Chae, D. H. Youn, H. T. Kim, S. Y. Maeng

We have grown VO2 thin films by laser ablation for electronic device applications. In obtaining the thin films of the pure VO2 phase, oxygen partial pressure is a critical parameter because vanadium oxides have several phases with the oxygen concentration. It is found that the pure VO2 films are epitaxially grown on Al2O3 substrate in the narrow ranges of 55

C. R. da Silva, U. L. Fulco, M. L. Lyra, G. M. Viswanathan

In this work, we study the critical behavior of an epidemic propagation model that considers individuals that can develop drug resistance. In our lattice model, each site can be found in one of four states: empty, healthy, normally infected (not drug resistant) and strain infected (drug resistant) states. The most relevant parameters in our model are related

Roberto Miatello, Ricardo Podesta

Let $M$ be an orientable compact flat Riemannian manifold endowed with a spin structure. In this paper we determine the spectrum of Dirac operators acting on smooth sections of twisted spinor bundles of $M$, and we derive a formula for the corresponding eta series. In the case of manifolds with holonomy group $\Z_2^k$, we give a very simple expression for th

Hanfeng Li

We introduce a new quantum Gromov-Hausdorff distance between C*-algebraic compact quantum metric spaces. Because it is able to distinguish algebraic structures, this new distance fixes a weakness of Rieffel's quantum distance. We show that this new quantum distance has properties analogous to the basic properties of the classical Gromov-Hausdorff distance, a

H. Lu, C. N. Pope, K. S. Stelle, P. K. Townsend

The equations of 10 or 11 dimensional supergravity admit supersymmetric compactifications on 7-manifolds of $G_2$ holonomy, but these supergravity vacua are deformed away from special holonomy by the higher-order corrections of string or M-theory. We find simple expressions for the first-order corrections to the Einstein and Killing spinor equations in terms

G. N. Wells, K. Garikipati, L. Molari

The numerical solution of strain gradient-dependent continuum problems has been dogged by continuity demands on the basis functions. For most commonly accepted models, solutions using the finite element method demand $C^{1}$ continuity of the shape functions. Here, recent development in discontinuous Galerkin methods are explored and exploited for the soluti

H. L. Haroutyunyan, G. Nienhuis

The relative phase between two uncoupled BE condensates tends to attain a specific value when the phase is measured. This can be done by observing their decay products in interference. We discuss exactly solvable models for this process in cases where competing observation channels drive the phases to different sets of values. We treat the case of two modes

Hanfeng Li

We introduce a new distance dist_oq between compact quantum metric spaces. We show that dist_oq is Lipschitz equivalent to Rieffel's distance dist_q, and give criteria for when a parameterized family of compact quantum metric spaces is continuous with respect to dist_oq. As applications, we show that the continuity of a parameterized family of quantum metric

Liliya L. R. Williams, Arif Babul, Julianne J. Dalcanton

Although high-resolution N-body simulations make robust empirical predictions for the density distribution within cold dark matter halos, these studies have yielded little physical insight into the origins of the distribution. We investigate the problem using analytic and semi-analytic approaches. Simple analytic considerations suggest that the inner slope o

E. Perez

Searches for R-parity violating supersymmetry performed at the H1 experiment are presented. Emphasis is put on searches for squarks, which may be resonantly produced at the HERA $ep$ collider in supersymmetry where R-parity is violated. The preliminary results presented here were obtained using data collected at a centre-of-mass energy of 320 GeV and corresp

W. C. Keel

I present two-band HST STIS imaging, and WIYN spectral mapping, of ongoing mass transfer in the interacting galaxy pair NGC 1409/10 (where NGC 1410 is the Seyfert galaxy also catalogued as III Zw 55). Archival snapshot WFPC2 imaging from the survey by Malkan et al. showed a dust feature stretching between the galaxies, apparently being captured by NGC 1409.

L. Francis, J. -M. Friedt, C. Zhou, P. Bertrand

We show the theoretical and experimental combination of acoustic and optical methods for the in situ quantitative evaluation of the density, the viscosity and the thickness of soft layers adsorbed on chemically tailored metal surfaces. For the highest sensitivity and an operation in liquids, a Love mode surface acoustic wave (SAW) sensor with a hydrophobized

Luis A. Anchordoqui, Jonathan L. Feng, Haim Goldberg, Alfred D. Shapere

Black hole production in elementary particle collisions is among the most promising probes of large extra spacetime dimensions. Studies of black holes at particle colliders have assumed that all of the incoming energy is captured in the resulting black hole. We incorporate the inelasticity inherent in such processes and determine the prospects for discoverin

Ruth Britto, Bo Feng, Oleg Lunin, Soo-Jong Rey

We construct the exact solution of one (anti)instanton in N=1/2 super Yang-Mills theory defined on non(anti)commutative superspace. We first identify N = 1/2 superconformal invariance as maximal spacetime symmetry. For gauge group U(2), SU(2) part of the solution is given by the standard (anti)instanton, but U(1) field strength also turns out nonzero. The so

Michael Christ, Loukas Grafakos, Petr Honzik, Andreas Seeger

We show that maximal operators formed by dilations of Mikhlin-H"ormander multipliers are typically not bounded on $L^p(R^d)$. We also give rather weak conditions in terms of the decay of such multipliers under which $L^p$ boundedness of the maximal operators holds.

K. Basu, C. Hernandez-Monteagudo, R. Sunyaev

The metallicity evolution and ionization history of the universe must leave its imprint on the Cosmic Microwave Background through resonant scattering of CMB photons by atoms, ions and molecules. These transitions partially erase original temperature anisotropies of the CMB, and also generate new fluctuations. In this paper we propose a method to determine t

Alexey A. Petrov

We review recent developments in charm physics, focusing on the physics of charmed mesons. We discuss charm spectroscopy, decay constants, as well as searches for new physics with charmed mesons. We discuss D0-anti-D0 mixing and CP-violation in charm decays. We also present the modified Nelson plot of charm mixing predictions.

Simon Catterall, Sofiane Ghadab

We show how to construct lattice sigma models in one, two and four dimensions which exhibit an exact fermionic symmetry. These models are discretized and {\it twisted} versions of conventional supersymmetric sigma models with N=2 supersymmetry. The fermionic symmetry corresponds to a scalar BRST charge built from the original supercharges. The lattice theori

Douglas A. Galbi

The history of the occupations "author" and "photographer" provides an insightful perspective on copyright and creativity. The concept of the romantic author, associated with personal creative genius, gained prominence in the eighteenth century. However, in the U.S. in 1900 only about three thousand persons professed their occupation to be "author." Self-pro