December 2005 arXiv papers — page 17

M. Hoesch, T. Fukuda, T. Takenouchi, J. P. Sutter

We observe strong softening of optical phonon modes in superconducting (Tc = 4.2 K) boron doped diamond near the Brillouin zone center using inelastic x-ray scattering from a CVD-grown highly oriented sample. The magnitude of the softening, and our observation that it becomes stronger approaching zone center, supports theoretical models suggesting a phonon-m

J. Q. You, Yu-xi Liu, C. P. Sun, Franco Nori

We propose a tunable on-chip micromaser using a superconducting quantum circuit (SQC). By taking advantage of externally controllable state transitions, a state population inversion can be achieved and preserved for the two working levels of the SQC and, when needed, the SQC can generate a single photon. We can regularly repeat these processes in each cycle

Guoming Wang, Mingsheng Ying

We address the problem of unambiguous discrimination among a given set of quantum operations. The necessary and sufficient condition for them to be unambiguously distinguishable is derived in the cases of single use and multiple uses respectively. For the latter case we explicitly construct the input states and corresponding measurements that accomplish the

Detlev Buchholz, Stephen J. Summers

We study a weakly local, but nonlocal model in spacetime dimension $d \geq 2$ and prove that it is maximally nonlocal in a certain specific quantitative sense. Nevertheless, depending on the number of dimensions $d$, it has string--localized or brane--localized operators which commute at spatial distances. In two spacetime dimensions, the model even comprise

I. Dolce, R. Passante, F. Persico

We consider three two-level atoms inside a one-dimensional cavity, interacting with the electromagnetic field in the rotating wave approximation (RWA), commonly used in the atom-radiation interaction. One of the three atoms is initially excited, and the other two are in their ground state. We numerically calculate the propagation of the field spontaneously e

Gavriel Segre

A simple formal recasting of well known arguments concerning the ordering problems of General Relativity allows to obtain in such a context a Gröenewald Van Hove like theorem.

Andrei Khrennikov

We develop an analogue of probability theory for probabilities taking values in topological groups. We generalize Kolmogorov's method of axiomatization of probability theory: main distinguishing features of frequency probabilities are taken as axioms in the measure-theoretic approach. We also present a review of non-Kolmogorovian probabilistic models inc

Alexander Borichev, Yurii Lyubarskii

For a scale of spaces $X$ of functions analytic in the unit disc, including the Korenblum space, and for some natural families $\mathcal E$ of uniqueness subsets for $X$, we describe minorants for $(X,\mathcal E)$, that is non-decreasing functions $M:(0,1)\to(0,\infty)$ such that $f\in X$, $E\in\mathcal E$, and $\log|f(z)|\le -M(|z|)$ on $E$ imply $f=0$. We

Vilmos Totik

In this survey, different aspects of the theory of orthogonal polynomials of one (real or complex) variable are reviewed. Orthogonal polynomials on the unit circle are not discussed.

E. H. Saidi, M. B. Sedra

Methods developed for the analysis of integrable systems are used to study the problem of hyperKähler metrics building as formulated in D=2 N=4 supersymmetric harmonic superspace. We show, in particular, that the constraint equation $β\partial^{++2}ω-ξ^{++2}\exp 2βω=0$ and its Toda like generalizations are integrable. Explicit solutions together with the con

M. V. Libanov, E. Y. Nugaev

We study Higgs boson properties in a model where three fermionic families of the Standard Model arise from a single generation in (5+1) dimensions. We demonstrate that, in spite of a non-trivial background, properties of the four-dimensional Higgs particle are almost indistinguishable from those in the Standard Model. We also argue that it is more natural to

M. A. Markova, Yu. A. Markov

Within the framework of the effective theory for ultrasoft field modes a problem of interacting an energetic color particle with ultrasoft fluctuations in hot gluon plasma is considered. The procedure of calculation of certain effective current generating the process of interaction is proposed, and the problem of its gauge independence is discussed. The appl

Guihua Tian

The stability of the Schwarzschild black hole is studied. Using the Painlevé coordinate, our region can be defined as the black-hole-connected region(r>2m, see text) of the Schwarzschild black hole or the white-hole-connected region(r>2m, see text) of the Schwarzschild black hole. We study the stable problems of the black-hole-connected region. The conclusio

Igal Sason, Gil Wiechman

The paper presents bounds on the achievable rates and the decoding complexity of low-density parity-check (LDPC) codes. It is assumed that the communication of these codes takes place over statistically independent parallel channels where these channels are memoryless, binary-input and output-symmetric (MBIOS). The bounds are applied to punctured LDPC codes.

Igal Sason, Gil Wiechman

The paper is focused on the tradeoff between performance and decoding complexity per iteration for LDPC codes in terms of their gap (in rate) to capacity. The study of this tradeoff is done via information-theoretic bounds which also enable to get an indication on the sub-optimality of message-passing iterative decoding algorithms (as compared to optimal ML

Igal Sason, Shlomo Shamai

Upper and lower bounds on the error probability of linear codes under maximum-likelihood (ML) decoding are shortly surveyed and applied to ensembles of codes on graphs. For upper bounds, focus is put on Gallager bounding techniques and their relation to a variety of other reported bounds. Within the class of lower bounds, we address de Caen's based bound

Ioannis Z. Emiris, Elias P. Tsigaridas

We present algorithmic and complexity results concerning computations with one and two real algebraic numbers, as well as real solving of univariate polynomials and bivariate polynomial systems with integer coefficients using Sturm-Habicht sequences. Our main results, in the univariate case, concern the problems of real root isolation (Th. 19) and simultaneo

P. Bertet, I. Chiorescu, G. Burkard, K. Semba

We have studied the dephasing of a superconducting flux-qubit coupled to a DC-SQUID based oscillator. By varying the bias conditions of both circuits we were able to tune their effective coupling strength. This allowed us to measure the effect of such a controllable and well-characterized environment on the qubit coherence. We can quantitatively account for

Jason Alicea, Olexei I. Motrunich, Matthew P. A. Fisher

We explore spin-1/2 triangular antiferromagnets with both easy-plane and lattice exchange anisotropies by employing a dual vortex mapping followed by a fermionization of the vortices. Over a broad range of exchange anisotropy, this approach leads naturally to a ``critical'' spin liquid--the algebraic vortex liquid--which appears to be distinct from o

Amir Ahsan, Joseph Rudnick, Robijn Bruinsma

We propose a model for the elastic properties of RNA gels. The model predicts anomalous elastic properties in the form of a negative Poisson ratio and shape instabilities. The anomalous elasticity is generated by the non-Gaussian force-deformation relation of single-stranded RNA. The effect is greatly magnified by broken rotational symmetry produced by doubl

Yoshihiro Nishiyama

A transfer-matrix simulation scheme for the three-dimensional (d=3) bond percolation is presented. Our scheme is based on Novotny's transfer-matrix formalism, which enables us to consider arbitrary (integral) number of sites N constituting a unit of the transfer-matrix slice even for d=3. Such an arbitrariness allows us to perform systematic finite-size-

Christoph Stampfer, Stefan Rotter, Joachim Burgdoerfer

We investigate the role of quantum effects (e.g. zero-point energy fluctuations) in the physics of nanotube- and nanowire-based electromechanical sensors as discussed in a recent article [Postma et al., Appl. Phys. Lett. 86, 223105 (2005)]. Employing the quantum fluctuation-dissipation theorem we find that these effects pose additional limits on the dynamic

Saeed Ghanbari, Tien D. Kieu, Andrei Sidorov, Peter Hannaford

We propose the use of periodic arrays of permanent magnetic films for producing magnetic lattices of microtraps for confining, manipulating and controlling small clouds of ultracold atoms and quantum degenerate gases. Using analytical expressions and numerical calculations we show that periodic arrays of magnetic films can produce one-dimensional (1D) and tw

Ling-Nan Zou, Sidney R. Nagel

Myelin figures are long thin cylindrical structures that typically grow as a dense tangle when water is added to the concentrated lamellar phase of certain surfactants. We show that, starting from a well-ordered initial state, single myelin figures can be produced in isolation thus allowing a detailed study of their growth and stability. These structures gro

Kouichi Okunishi

We present a real-space renormalization group approach for the corner Hamiltonian, which is relevant to the reduced density matrix in the density matrix renormalization group. A set of self-consistent equations that the renormalized Hamiltonian should satisfy in the thermodynamic limit is also derived from the fixed point of the recursion relation for the co

Kevin Ingersent, Andreas W. W. Ludwig, Ian Affleck

Triangular symmetry stabilizes a novel non-Fermi-liquid phase in the three-impurity Kondo model with frustrating antiferromagnetic interactions between half-integer impurity spins. The phase arises without fine-tuning of couplings, and is stable against magnetic fields and particle-hole symmetry breaking. We find a conformal field theory describing this phas

H. Dannerbauer, E. Daddi, M. Onodera, X. Kong

We present MAMBO 1.2 mm observations of five BzK-pre-selected vigorous starburst galaxies at z~2. Two of these were detected at more than 99.5% confidence levels, with 1.2 mm fluxes around 1.5 mJy. These millimeter fluxes imply vigorous activity with star-formation rates (SFRs) approx. 500-1500 Msun/yr, confirmed also by detections at 24 microns with the MIP

Adrian Kent

Withdrawn -- a revised version will appear in due course.

J. C. D'Olivo, L. Nellen, S. Sahu, V. Van Elewyck

We present a calculation of the damping of an ultra-energetic (UHE) cosmic neutrino travelling through the thermal gas of relic neutrinos, using the formalism of finite-temperature field theory. From the self-energy diagram due to Z exchange, we obtain the annihilation cross section for an UHE neutrino interacting with an antineutrino from the background. Th

Alexandre Guillaume, Jonathan P. Dowling

We describe an assembly of N superconducting qubits contained in a single-mode cavity. In the dispersive regime, the correlation between the cavity field and each qubit results in an effective interaction between qubits that can be used to dynamically generate maximally entangled states. With only collective manipulations, we show how to create maximally ent

N. M. Law, S. T. Hodgkin, C. D. Mackay

We survey a sample of 32 M5-M8 stars with distance < 40pc for companions with separations between 0.1 arcsec and 1.5 arcsec and with Delta m_i <5. We find five new VLM binaries with separations between 0.15 arcsec and 1.1 arcsec, including a candidate brown dwarf companion. The raw binary fraction is 16% +8/-4% and the distance bias corrected fraction is 7%

Z. Burda, A. Krzywicki, O. C. Martin, Z. Tabor

Given discrete degrees of freedom (spins) on a graph interacting via an energy function, what can be said about the energy local minima and associated inherent structures? Using the lid algorithm in the context of a spin glass energy function, we investigate the properties of the energy landscape for a variety of graph topologies. First, we find that the mul

Vladimir V. Kisil

This paper presents an implementation of the Schwerdtfeger-Fillmore-Springer-Cnops construction (SFSCc) along with illustrations of its usage. SFSCc linearises the linear-fraction action of the Moebius group in R^n. This has clear advantages in several theoretical and applied fields including engineering. Our implementation is based on the Clifford algebra c

Vladimir V. Kisil

This paper presents geometrical foundation for a systematic treatment of three main (elliptic, parabolic and hyperbolic) types of analytic function theories based on the representation theory of SL(2,R) group. We describe here geometries of corresponding domains. The principal role is played by Clifford algebras of matching types. In this paper we also gener

Piotr Milos

Functional limit theorems are presented for the rescaled occupation time fluctuations process of a critical finite variance branching particle system in $R^d$ with symmetric a-stable motion starting off from either a standard Poisson random field or from the equilibrium distribution for intermediate dimensions a<d<2a. The limit processes are determined sub-f

Sasha Anan&#39;in, Nikolay Gusevskii

This article is based on the methods developed in [AGG]. We construct a complex hyperbolic structure on a trivial disc bundle over a closed orientable surface $Σ$ (of genus 2) thus solving a long standing problem in complex hyperbolic geometry (see [Gol1, p. 583] and [Sch, p. 14]). This example answers also [Eli, Open Question 8.1] if a trivial circle bundle

R. P. Thomas

These notes give an introduction to Geometric Invariant Theory and symplectic reduction, with lots of pictures and simple examples. We describe their applications to moduli of bundles and varieties, and their infinite dimensional analogues in gauge theory and the theory of special metrics on algebraic varieties. Donaldson&#39;s &#34;quantisation&#34; link be

Gao-Chan Yong, Bao-An Li, Lie-Wen Chen, Wei Zuo

Based on an isospin- and momentum-dependent hadronic transport model IBUU04, effects of the nuclear symmetry energy on the single and double pi^{-}/pi^{+}ratios in central reactions of ^{132}Sn+^{124}Sn and ^{112}Sn+^{112}Sn at a beam energy of 400 MeV/nucleon are studied. It is found that around the Coulomb peak of the single pi^{-}/pi^{+} ratio the double

L. Campanelli, M. Giannotti

We investigate the effects of an external magnetic helicity production on the evolution of the cosmic axion field. It is shown that a helicity larger than (few \times 10^{-15} G)^2 Mpc, if produced at temperatures above a few GeV, is in contradiction with the existence of the axion, since it would produce too much of an axion relic abundance.

Bogusław Broda, Marcin Ostrowski

The idea of the Michelson-Morley experiment is theoretically reanalyzed. Elementary arguments are put forward to precisely derive the most general allowable form of the directional dependence of the one-way velocity of light.

Kenji Kadota, J. Yokoyama

We discuss a D-term inflation scenario where a right-handed sneutrino can be an inflaton field leading to a viable inflation and leptogenesis, with a minimal form of Kähler potential. The decay of an inflaton sneutrino can non-thermally create large enough lepton asymmetry. Its entropy production is also big enough to ameliorate the gravitino problem caused

Yuichi Oyama

Results from the K2K experiment and status of the T2K experiment are reported.

N. Redington, M. A. K. Lodhi

A first-order relativistic wave equation is constructed in five dimensions. Its solutions are eight-component spinors, which are interpreted as single-particle fermion wave functions in four-dimensional spacetime. Use of a ``cylinder condition&#39;&#39; (the removal of explicit dependence on the fifth coordinate) reduces each eight-component solution to a pa

Renbin Yan, Jeffrey A. Newman, S. M. Faber, Nicholas Konidaris

We investigate the emission-line properties of galaxies with red rest-frame colors using spectra from SDSS DR4. Emission lines are detected in more than half of the red galaxies. We focus on the relationship between two emission lines commonly used as star formation rate indicators: Ha 6563 and [OII] 3727. There is a strong bimodality in [OII]/Ha ratio in th

Rennan Barkana, Abraham Loeb

The delay in light travel time along the line of sight generates an anisotropy in the power spectrum of 21cm brightness fluctuations from the epoch of reionization. We show that when the fluctuations in the neutral hydrogen fraction become non-linear at the later stages of reionization, the light-cone anisotropy becomes of order unity on scales >50 comoving

Y. Chen, Z. D. Wang, F. C. Zhang

We introduce a new measure called reduced entropy of sublattice to quantify entanglement in spin, electron and boson systems. By analyzing this quantity, we reveal an intriguing connection between quantum entanglement and quantum phase transitions in various strongly correlated systems: the local extremes of reduced entropy and its first derivative as functi

Caroline H Thompson

Recent proposed ``loophole-free&#39;&#39; Bell tests are discussed in the light of classical models for the relevant features of optical parametric amplification and homodyne detection. The Bell tests themselves are uncontroversial: there are no obvious loopholes that might cause bias and hence, if the world does, after all, obey local realism, no violation

V. P. Belavkin, P. Staszewski

A stochastic model of a continuous nondemolition observation of a free quantum Brownian motion is presented. The nonlinear stochastic wave equation describing the posterior dynamics of the observed quantum system is solved in a Gaussian case for a free particle of mass m. It is shown that the dispersion of the wave packet does not increase to infinity like f

V. P. Belavkin, P. Staszewski

A stochastic model for the continuous nondemolition ohservation of the position of a quantum particle in a potential field and a boson reservoir is given. lt is shown that any Gaussian wave function evolving according to the posterior wave equation with a quadratic potential collapses to a Gaussian wave packet given by the stationary solution of this equatio

V. P. Belavkin

A stochastic model for nondemolition continuous measurement in a quantum system is given. It is shown that the posterior dynamics, including a continuous collapse of the wave function, is described by a nonlinear stochastic wave equation. For a particle in an electromagnetic field it reduces the Schroedinger equation with extra imaginary stochastic potential

C. Vinegoni, T. Ralston, W. Tan, W. Luo

An integrated microscope that combines different optical techniques for simultaneous imaging is demonstrated. The microscope enables spectral-domain optical coherence microscopy based on optical backscatter, and multi-photon microscopy for the detection of two-photon fluorescence and second harmonic generation signals. The unique configuration of this integr

S. Jonsell, C. M. Dion, M. Nylén, S. J. H. Petra

We develop a semi-classical method to simulate the motion of atoms in a dissipative optical lattice. Our method treats the internal states of the atom quantum mechanically, including all nonadiabatic couplings, while position and momentum are treated as classical variables. We test our method in the one-dimensional case. Excellent agreement with fully quantu

A. A. Koronovskii, A. E. Hramov, A. E. Khramova

The dynamics of one-way coupled systems with discrete time is considered. The behavior of the coupled logistic maps is compared to the dynamics of maps obtained using the Poincare sectioning procedure applied to the coupled continuous-time systems in the phase synchronization regime. The behavior (previously considered as asynchronous) of the coupled maps th

A. E. Hramov, A. A. Koronovskii, O. I. Moskalenko

The behavior of two unidirectionally coupled chaotic oscillators near the generalized synchronization onset has been considered. The character of the boundaries of the generalized synchronization regime has been explained by means of the modified system

Alexander E. Hramov, Alexey A. Koronovskii, Pavel V. Popov

Generalized chaotic synchronization regime is observed in the unidirectionally coupled one-dimensional Ginzburg-Landau equations. The mechanism resulting in the generalized synchronization regime arising in the coupled spatially extended chaotic systems demonstrating spatiotemporal chaotic oscillations has been described. The cause of the generalized synchro

Romeo Brunetti, Martin Porrmann, Giuseppe Ruzzi

In this review we report on how the problem of general covariance is treated within the algebraic approach to quantum field theory by use of concepts from category theory. Some new results on net cohomology and superselection structure attained in this framework are included.

S. I. Tertychniy

The method of efficient description of long-term behavior of solutions of the non-linear first order ODE \dotϕ+\sinϕ=f for arbitrary periodic $f$ is discussed. The criterion enabling one to separate and identify the qualitatively different solutions is established. The applications of the method to the modeling of dynamics of overdamped Josephson junctions i

Georgia Benkart, Paul Terwilliger

We give a presentation of the universal central extension of the three-point loop algebra L over sl_2 by generators and relations. Our presentation arises from the realization of L as the tetrahedron Lie algebra and leads to connections between the universal central extension and the Onsager Lie algebra. Symmetry under the alternating group A_4 features prom

Alexander Engström

Karp conjectured that all nontrivial monotone graph properties are evasive. This was proved for n a prime power, and n=6, where n is the number of graph vertices, by Kahn, Saks, and Sturtevant. We give a complete description of which transitive graphs are contained in a possible counterexample when n=10.

Alexander Engström

We study the class of independence complexes of claw-free graphs. The main theorem give good bounds on the connectivity of these complexes, given bounds for a few subcomplexes of the same class. Two applications are presented. Firstly, we show that the independence complex of a claw-free graph with n vertices and maximal degree d is (cn/d+epsilon)-connected,

N. Bruin, K. Gyory, L. Hajdu, Sz. Tengely

In this paper we present some new results about unlike powers in arithmetic progression. We prove among other things that for given $k\geq 4$ and $L\geq 3$ there are only finitely many arithmetic progressions of the form $(x_0^{l_0},x_1^{l_1},...,x_{k-1}^{l_{k-1}})$ with $x_i\in{\Bbb Z},$ gcd$(x_0,x_1)=1$ and $2\leq l_i\leq L$ for $i=0,1,...,k-1.$ Furthermor

F. Beukers, Sz. Tengely

In this paper we suggest an implementation of Runge&#39;s method for solving Diophantine equations satisfying Runge&#39;s condition. In this implementation we avoid the use of Puiseux series and algebraic coefficients.

V. P. Belavkin

A history and drama of the development of quantum probability theory is outlined starting from the discovery of the Plank&#39;s constant exactly a 100 years ago. It is shown that before the rise of quantum mechanics 75 years ago, the quantum theory had appeared first in the form of the statistics of quantum thermal noise and quantum spontaneous jumps which h

V. P. Belavkin

We give an axiomatic formulation of quantum structures like semilogics and quasilogics which generalize the boolean semirings of events and fuzzy logics. The notions of distributions, states, representations observables and semiobservables are introduced and their Hilbert space realizations are found. The closed and open structures in semilogics are introduc

R. P. Thomas

We give a brief survey of some of the geometry of mirror symmetry, written in 2004 for the &#34;Encyclopaedia of Mathematical Physics&#34;. Probably a little bit out of date now in a few places, but hey.

V. P. Belavkin

Statistically interpretable axioms are formulated that define a quantum stochastic process (QSP) as a causally ordered operator field in an arbitrary space-time region T of an open quantum system under a sequential observation at a discrete space-time localization. It is shown that to every QSP described in the weak sense by a self-consistent system of causa

Harish Seshadri, Kaushal Verma

Let (M,g) be a simply connected complete Kahler manifold with nonpositive sectional curvature. Assume that g has constant negative holomorphic sectional curvature outside a compact set. We prove that M is then biholomorphic to the unit ball in C^n, where dim M = n.

Dongwen Qi

The aim of this note is to prove that the parabolic closure of any subset of a Coxeter group is a parabolic subgroup. To obtain that, several technical lemmas on the root system of a parabolic subgroup are established.

E. S. Esyp, I. V. Kazachkov, V. N. Remeslennikov

The original version of the paper was published in Contemporary Mathematics 378 ``Groups, Languages, Algorithms&#39;&#39;; 2005, pp. 319-348. This is a modified version with Appendix that holds a corrected formulation of Proposition 4.1.

Ian Ellwood, Akikazu Hashimoto

We describe how the matrix integral of Imbimbo and Mukhi arises from a limit of the FZZT partition function in the double-scaled c=1 matrix model. We show a similar result for 0A and comment on subtleties in 0B.

N. Caporaso, M. Cirafici, L. Griguolo, S. Pasquetti

The counting of microstates of BPS black-holes on local Calabi-Yau of the form ${\mathcal O}(p-2)\oplus{\mathcal O}(-p) \longrightarrow S^2$ is explored by computing the partition function of q-deformed Yang-Mills theory on $S^2$. We obtain, at finite $N$, the instanton expansion of the gauge theory. It can be written exactly as the partition function for U(

Matthias Neubert

These notes are based on five lectures presented at the 2004 Theoretical Advanced Study Institute (TASI) on ``Physics in D>=4&#39;&#39;. After a brief motivation of flavor physics, they provide a pedagogical introduction to effective field theory, the effective weak Lagrangian, and the technology of renormalization-group improved perturbation theory. These g

L. Nilse

We study five-dimensional Yang-Mills theories compactified on an S^1/Z_2 orbifold. The fundamental Lagrangian naturally includes brane kinetic terms at the orbifold fixed points which are induced by quantum corrections of the bulk fields. The theories are quantized in the higher-dimensional R_xi gauges before compactification. Using Ward and Slavnov-Taylor i

Frank Wilczek

I discuss the historical and conceptual roots of reasoning about the parameters of fundamental physics and cosmology based on selection effects. I argue concretely that such reasoning can and should be combined with arguments based on symmetry and dynamics; it supplements them, but does not replace them.

Marcin Raczkowski, Andrzej M. Oles, Raymond Fresard

Based on the mean-field method applied either to the extended single-band Hubbard model or to the single-band Peierls-Hubbard Hamiltonian we study the stability of both site-centered and bond-centered charge domain walls. The difference in energy between these phases is found to be small. Therefore, moderate perturbations to the pure Hubbard model, such as n

Hiroshi Watanabe, Chin-Kun Hu

The article is an reply to comments on the paper [H. Watanabe, S. Yukawa, N. Ito, and C.-K. Hu, Phys. Rev. Lett. vol. 93, 19601 (2004)] by G. Pruessner and N. R. Moloney published in [Phys. Rev. Lett. vo. 95, 258901 (2005)]. In this reply, we also point out that the exponents $a$ and $b$ in the 2004 paper just mentioned can be calculated from mapping functio

V. U. Nazarov, C. S. Kim, Y. Takada

We revisit the problem of the spontaneous magnetization of an {\em sp} impurity atom in a simple metal host. The main features of interest are: (i) Formation of the spherical spin density/charge density wave around the impurity; (ii) Considerable decrease in the size of the pseudoatom in the spin-polarized state as compared with the paramagnetic one, and (ii

David Prendergast, Giulia Galli

We present a series of ab-initio calculations of spectroscopic properties of liquid water at ambient conditions. Our results show that all available theoretical and experimental evidence is consistent with the standard model of the liquid as comprising molecules with approximately four hydrogen bonds. In particular, this model cannot be discounted on the bas

Ulf von Barth, Nils Erik Dahlen, Robert van Leeuwen, Gianluca Stefanucci

In the present work we propose a theory for obtaining successively better approximations to the linear response functions of time-dependent density or current-density functional theory. The new technique is based on the variational approach to many-body perturbation theory (MBPT) as developed during the sixties and later expanded by us in the mid nineties. D

Stefan Kirchner, Lijun Zhu, Qimiao Si, D. Natelson

Considerable evidence exists for the failure of the traditional theory of quantum critical points (QCPs), pointing to the need to incorporate novel excitations. The destruction of Kondo entanglement and the concomitant critical Kondo effect may underlie these emergent excitations in heavy fermion metals -- a prototype system for quantum criticality -- but th

Wei Fa, Chuanfu Luo, Jinming Dong

Using the relativistic all-electron density-functional calculations on the AuN (N=2-26) in the generalized gradient approximation, combined with the guided simulated annealing, we have found that the two- to three-dimensional structural transition for AuN occurs between N=13 and 15, and the AuN (16<= N <=25) prefer also the pyramid-based bulk fragment struct

Hiroaki Kadowaki, Yoshikazu Tabata, Masugu Sato, Naofumi Aso

A quantum critical point (QCP) of the heavy fermion Ce(Ru_{1-x}Rh_x)_2Si_2 (x = 0, 0.03) has been studied by single-crystalline neutron scattering. By accurately measuring the dynamical susceptibility at the antiferromagnetic wave vector k_3 = 0.35 c^*, we have shown that the energy width Gamma(k_3), i.e., inverse correlation time, depends on temperature as

S. Y. Liu, X. L. Lei

We present a two-band kinetic equation method to investigate the anomalous Hall effect in a Rashba two-dimensional electron system subjected to a homogeneous magnetization. The electron-impurity scattering is taken into account in the self-consistent Born approximation. It is demonstrated that the impurity-density-free anomalous Hall conductivity arises from

V. I. Kozub, Y. M. Galperin, V. Vinokur

We propose a mechanism for 1/f-type noise in hopping insulators based on the multi-electron charge redistribution within the specific aggregates of the localized states located in the vicinity of the critical resistors. We predict that the noise with 1/f-type spectrum extends down to practically arbitrarily low frequencies.

Ramin Skibba, Ravi K. Sheth, Andrew J. Connolly, Ryan Scranton

We present measurements of the redshift-space luminosity-weighted or `marked&#39; correlation function in the SDSS. These are compared with a model in which the luminosity function and luminosity dependence of clustering are the same as that observed, and in which the form of the luminosity-weighted correlation function is entirely a consequence of the fact

Jenny E. Greene, Luis C. Ho

(ABRIDGED) We present stellar velocity dispersion (sigma*) measurements for a significant sample of 40 broad-line (Type 1) active galaxies for use in testing the well-known relation between black hole mass and stellar velocity dispersion. The objects are selected to contain Ca II triplet, Mgb triplet, and Ca H+K stellar absorption features in their optical s

Jenny E. Greene, Luis C. Ho

We examine whether active galaxies obey the same relation between black hole mass and stellar velocity dispersion as inactive systems, using the largest published sample of velocity dispersions for active nuclei to date. The combination of 56 original measurements with objects from the literature not only increases the sample from the 15 considered previousl

The Tibet AS Gamma Collaboration, M. Amenomori

We searched for steady PeV gamma-ray emission from the Monogem ring region with the Tibet air shower array from 1997 February to 2004 October. No evidence for statistically significant gamma-ray signals was found in a region 111$\degr$ $\leq$ R.A. $<$ 114$\degr$, 12$\fdg$5 $\leq$ decl. $<$ 15$\fdg$5 in the Monogem ring where the MAKET-ANI experiment recently

J. S. Zhang, C. Henkel, M. Kadler, L. J. Greenhill

Having conducted a search for the 22 GHz water vapor line towards galaxies with nuclear activity, large nuclear column densities or high infrared luminosities, we present H_2O spectra for NGC2273, UGC5101 and NGC3393 with isotropic luminosities of 7, 1500, and 400 L_sun. The H_2O maser in UGC5101 is by far the most luminous yet found in an ultraluminous infr

Brice Ménard, Stefano Zibetti, Daniel Nestor, David Turnshek

Using a large sample of MgII absorbers with 0.4<z<2.2 detected by Nestor et al (2005) in the Early Data Release of the SDSS, we present new constraints on the physical properties of these systems based on two statistical analyses: (i) By computing the ratio between the composite spectra of quasars with and without absorbers, we measure the reddening effects

M. Haverkorn, B. M. Gaensler, J. C. Brown, N. S. Bizunok

We present an analysis of the rotation measures (RMs) of polarized extragalactic point sources in the Southern Galactic Plane Survey. This work demonstrates that the statistics of fluctuations in RM differ for the spiral arms and the interarm regions. Structure functions of RM are flat in the spiral arms, while they increase in the interarms. This indicates

J. -M. Wang, Y. -M. Chen, C. Hu

Seed black holes formed in the collapse of population III stars have been invoked to explain the presence of supermassive black holes at high redshift. It has been suggested that a seed black hole can grow up to $10^{5\sim 6}\sunm$ through highly super-Eddington accretion for a period of $\sim 10^{6\sim 7}$ yr between redshift $z=20\sim 24$. We studied the f

C. D. Froggatt, H. B. Nielsen

We propose that dark matter consists of collections of atoms encapsulated inside pieces of an alternative vacuum, in which the Higgs field vacuum expectation value is appreciably smaller than in the usual vacuum. The alternative vacuum is supposed to have the same energy density as our own. Apart from this degeneracy of vacuum phases, we do not introduce any

J. Harnad, A. Yu. Orlov

A new representation of the 2N fold integrals appearing in various two-matrix models that admit reductions to integrals over their eigenvalues is given in terms of vacuum state expectation values of operator products formed from two-component free fermions. This is used to derive the perturbation series for these integrals under deformations induced by expon

Joanna Kiryluk

We present preliminary results for the first measurements of the double longitudinal spin asymmetry A_LL in inclusive jet production at mid-rapidity in polarized proton-proton collisions at sqrt(s) = 200 GeV. The data amount to ~ 0.5 pb-1 collected at RHIC in 2003 and 2004 with beam polarizations up to 45%. The jet transverse energies are in the range of 5 <

E. Accomando, A. Ballestrero, S. Bolognesi, E. Maina

Boson-boson scattering and Higgs production in boson-boson fusion hold the key to electroweak symmetry breaking. In order to analyze these essential features of the Standard Model we have performed a partonic level study of all processes $q_1 q_2 \to q_3 q_4 q_5 q_6 l ν$ at the LHC using the exact matrix elements at $Ø(α_{em}^6)$ provided by \Phase, a new MC

Risa H. Wechsler, Andrew R. Zentner, James S. Bullock, Andrey V. Kravtsov

We investigate the dependence of dark matter halo clustering on halo formation time, density profile concentration, and subhalo occupation number, using high-resolution numerical simulations of a LCDM cosmology. We confirm results that halo clustering is a function of halo formation time, and that this trend depends on halo mass. For the first time, we show

Tamon Stephen, Hugh Thomas

We show that any point in the convex hull of each of (d+1) sets of (d+1) points in R^d is contained in at least floor((d+2)^2/4) simplices with one vertex from each set.

T. Jungk, A. Hoffmann, E. Soergel

The interpretation of ferroelectric domain images obtained with piezoresponse force microscopy (PFM) is discussed. The influences of an inherent experimental background on the domain contrast in PFM images (enhancement, nulling, inversion) as well as on the shape and the location of the domain boundaries are described. We present experimental results to evid

Pengjie Zhang

The decay rate of cosmological gravitational potential measures the deviation from Einstein-de Sitter universe and can put strong constraints on the nature of dark energy and gravity. Usual method to measure this decay rate is through the integrated Sachs-Wolfe (ISW) effect-large scale structure (LSS) cross correlation. However, the interpretation of the mea