February 2001 arXiv papers — page 9

J. P. Pekola, J. J. Toppari

We discuss dephasing by the dissipative electromagnetic environment and by measurement in circuits consisting of small Josephson junctions. We present quantitative estimates and determine in which case the circuit might qualify as a quantum bit. Specifically, we analyse a three junction Cooper pair pump and propose a measurement to determine the decoherence

A. Nowicka, M. R. Dudek, S. Cebrat, M. Kowalczuk

We have analyzed DNA sequences of known genes from 16 yeast chromosomes (Saccharomyces cerevisiae) in terms of oligonucleotides. We have noticed that the relative abundances of oligonucleotide usage in the genome follow a long-tail Levy-like distribution. We have observed that long genes often use strongly over-represented and under-represented nucleotides,

F. Schmitt, D. Marsan

Discrete multiplicative turbulent cascades are described using a formalism involving infinitely divisible random measures. This permits to consider the continuous limit of a cascade developed on a continuum of scales, and to provide the stochastic equations defining such processes, involving infinitely divisible stochastic integrals. Causal evolution laws ar

Philippe Jacquod

It is shown that off-diagonal fluctuations of interaction lead to the breakdown of perturbation theory in the immediate vicinity of the ground-state of a fermionic system at a rate inversely proportional to the number of considered particles. This rate is parametrically much faster than previously expected. It is shown that this follows from the coherent add

A. Kambili, H. Fehrmann, C. J. Lambert, J. H. Jefferson

In this paper, we investigate the ground state of two-dimensional disordered cylinders which contain spinless, interacting electrons using the Hartree-Fock approximation. Calculations of the deviation of the polarization from uniformity reveal a tendency of the charge to rearrange towards the ends of the system. The presence of disorder results in fluctuatio

T. Jarlborg

A theory for spin and lattice couplings to the electronic states in high-T$_C$ oxides is presented, with HgBa$_2$CuO$_4$ as an example. A simple analytical model suggests that the barrel band is sensitive to potential perturbations with long-range Fourier components, and that gaps can be opened at the Fermi energy. This is confirmed in self-consistent band c

Jun-ichi Igarashi, Manabu Takahashi

We study the resonant x-ray magnetic scattering (RXMS) around the K edge of Ni in the antiferromagnet NiO, by treating the 4p states of Ni as a band and the 3d states as localized states. We propose a mechanism that the 4p states are coupled to the magnetic order through the intra-atomic Coulomb interaction between the 4p and the 3d states and through the p-

E. M. Monier, S. Mathur, B. Wilkes, M. Elvis

The presence of a ``warm absorber'' was first suggested to explain spectral variability in an X-ray spectrum of the radio-quiet QSO MR2251-178. A unified picture, in which X-ray warm absorbers and ``intrinsic'' UV absorbers are the same, offers the opportunity to probe the nuclear environment of active galactic nuclei. To test this scenario a

H. W. Duerbeck, M. L. Hazen, A. A. Misch, W. C. Seitter

``Nova Aquilae No. 4'', discovered in 1919, later renamed V605 Aql, was recognized to be a final helium flash object only in the 1980s. Clayton and De Marco (1997) gave a detailed description of the available spectroscopic and photometric material. Here we try to re-analyze the photometric record. The photographic material is still available and has

H. W. Duerbeck

The optical photometric evolution of the final helium flash object V4334 Sgr from 1994 to 2000 is described. The rise to optical maximum (1994 - 1996) is characterized by a continuous increase of color indices, indicating a slowly expanding, cooling pseudo-photosphere. This photosphere became stationary in 1997. In the following years, the object underwent b

Jeremy Darling, Riccardo Giovanelli

We present current results of an ongoing survey for OH megamasers in luminous infrared galaxies at the Arecibo Observatory. The survey is now two-thirds complete, and has resulted in the discovery of 35 new OH megamasers at z > 0.1, 24 of which are presented in this paper. We discuss the properties of each source in detail, including an exhaustive survey of

Paul H. Frampton

Analytic formulas for the position of the first acoustic peak in the CMB are derived and discussed. They are generalized to the case of a time-dependent dark energy component and it is shown how the cosmic parameters $Ω_M$ and $Λ_Λ$, extracted from observations, have an intrinsic uncertainty until one knows whether the dark energy density is, or is not, time

O. Elgaroy, F. V. De Blasio

A microscopic, quantum mechanical model for neutron vortices in the crust of a neutron star is presented. After a brief introduction to the Bogoliubov- de Gennes equations, which form the basis for our calculations, we present results for density distributions, vortex core sizes and vortex energies, both for an isolated neutron vortex and for the case when t

Trevor C. Weekes

The first experiment in which radio emission was detected from high energy particles is described. An array of dipoles was operated by a team of British and Irish physicists in 1964-5 at the Jodrell Bank Radio Observatory in conjunction with a simple air shower trigger. The array operated at 44 MHz with 2.75 MHz bandwidth. Out of 4,500 triggers a clear bandw

Charles R. Keeton

Modern applications of strong gravitational lensing require the ability to use precise and varied observational data to constrain complex lens models. I discuss two sets of computational methods for lensing calculations. The first is a new algorithm for solving the lens equation for general mass distributions. This algorithm makes it possible to apply arbitr

Joseph A. Biello

Layer formation in a thermally destabilized fluid with stable density gradient has been observed in laboratory experiments and has been proposed as a mechanism for mixing molecular weight in late stages of stellar evolution in regions which are unstable to semiconvection. It is not yet known whether such layers can exist in a very low viscosity fluid: this w

J. D. Kurk, H. J. A. Rottgering, G. K. Miley, L. Pentericci

The radio galaxy MRC 1138-262 at z=2.16 is most likely a brightest cluster galaxy in an early stage of evolution. Here we present observations of the luminous emission line halo and the stellar components of this radio galaxy. Optical narrow band imaging shows a very extended (about 160 kpc) and luminous Lyman alpha halo. Infrared narrow band imaging reveals

Griet C. Van de Steene, George H. Jacoby

We observed 64 newly identified galactic bulge planetary nebulae in the radio continuum at 3 and 6 cm with the Australia Telescope Compact Array. We present their radio images, positions, flux densities, and angular sizes. The survey appears to have detected a larger ratio of more extended planetary nebulae with low surface brightness than in previous survey

Yoji Osaki, Friedrich Meyer, Emmi Meyer-Hofmeister

A WZ Sge-type dwarf nova, EG Cancri, exhibited six consecutive mini-outbursts with a mean interval of about seven days after the end of the main outburst in 1996/1997. Most unusual was that the star abruptly entered into a deep faint minimum after such frantic activities. We propose that this peculiar phenomenon may be understoodin terms of viscosity decay i

C. S. Kochanek, Martin White

The halo mass function, dn/dM, predicted by hierarchical clustering models can be measured indirectly using dynamical probes like the distribution of gravitational lens image separations, dn/dDelta-theta, or halo circular velocities, dn/d v_c. These dynamical variables depend on the halo structure as well as the halo mass. Since baryonic physics, particularl

K. Meisenheimer, M. Haas, S. A. H. Müller, R. Chini

In order to test the unified scheme for luminous radio galaxies and quasars we observed 10 galaxy/quasar pairs from the 3CR catalogue with ISOPHOT at infrared wavelengths between 5 and 180 micron. Each pair was selected such that both the 178 MHz luminosity and the redshift match as close as possible between the radio galaxy and the quasar in order to minimi

Barbara Paltrinieri, Francesco R. Ferraro, Francesco Paresce, Guido De Marchi

We present extensive UBVR photometry of the Galactic globular cluster (GGC) NGC6712 obtained with the ESO Very Large Telescope (VLT) which reach down to two magnitudes below the main sequence turn-off and allows us for the first time to determine the age of this cluster. By using the apparent luminosity of the zero age horizontal branch (ZAHB), $V_{ZAHB}=16.

Zhigang Gong, Ladislav Zejda, Werner Dappen, Josep M. Aparicio

The generalized Fermi-Dirac functions and their derivatives are important in evaluating the thermodynamic quantities of partially degenerate electrons in hot dense stellar plasmas. New recursion relations of the generalized Fermi-Dirac functions have been found. An effective numerical method to evaluate the derivatives of the generalized Fermi-Dirac function

A. J. Castro-Tirado, V. V. Sokolov, J. Gorosabel, J. M. Castro Cerón

Observations of the extraordinarily bright optical afterglow (OA) of GRB 991208 started 2.1 d after the event. The flux decay constant of the OA in the R-band is -2.30 +/- 0.07 up to 5 d, which is very likely due to the jet effect, and after that it is followed by a much steeper decay with constant -3.2 +/- 0.2, the fastest one ever seen in a GRB OA. A negat

B. Pioline, H. Nicolai, J. Plefka, A. Waldron

This letter is an attempt to carry out a first-principle computation in M-theory using the point of view that the eleven-dimensional membrane gives the fundamental degrees of freedom of M-theory. Our aim is to derive the exact BPS $R^4$ couplings in M-theory compactified on a torus $T^{d+1}$ from the toroidal BPS membrane, by pursuing the analogy with the on

T. W. Kephart, H. Päs

We propose a standard model minimal extension with two lepton weak SU(2) doublets and a scalar singlet to explain the deviation of the measured anomalous magnetic moment of the muon from the standard model expectation. This scheme can be naturally motivated in string inspired models such as E_6 and AdS/CFT.

Jason Manning

We outline a rigorous algorithm, first suggested by Casson, for determining whether a closed orientable 3-manifold M is hyperbolic, and to compute the hyperbolic structure, if one exists. The algorithm requires that a procedure has been given to solve the word problem in π_1(M).

Robert V. Harlander, William B. Kilgore

The contributions of virtual corrections and soft gluon emission to the inclusive Higgs production cross section pp -> H + X are computed at next-to-next-to-leading order in the heavy top quark limit. We show that this part of the total cross section is well behaved in the sense of perturbative convergence, with the NNLO corrections amounting to an enhanceme

Xuepeng Sun, Hans J. Weber

A method for constructing a complete set of relativistic three-quark states in light front dynamics is implemented for the nucleon, N$^*$(1520) and N$^*$(1535). This approach facilitates constructing states containing virtual antiquarks. A physical interpretation is provided in terms of transition amplitudes from quark to quark-gluon or quark-Goldstone boson

Illes J. Farkas, Imre Derenyi, Albert-Laszlo Barabasi, Tamas Vicsek

Many natural and social systems develop complex networks, that are usually modelled as random graphs. The eigenvalue spectrum of these graphs provides information about their structural properties. While the semi-circle law is known to describe the spectral density of uncorrelated random graphs, much less is known about the eigenvalues of real-world graphs,

A. P. Baeta Scarpelli, M. Sampaio, M. C. Nemes, B. Hiller

This is the second in a series of two contributions in which we set out to establish a novel momentum space framework to treat field theoretical infinities in perturbative calculations when parity-violating objects occur. Since no analytic continuation on the space-time dimension is effected, this framework can be particularly useful to treat dimension-speci

C. I. Lazaroiu

I discuss the axiomatic framework of (tree-level) associative open string field theory in the presence of D-branes by considering the natural extension of the case of a single boundary sector. This leads to a formulation which is intimately connected with the mathematical theory of differential graded categories. I point out that a generic string field theor

Thomas Schaefer

Inspired by a recent proposal for a Higgs description of QCD we study the possible formation of a color-octet/flavor-octet quark-anti-quark condensate in the instanton liquid model. For this purpose we calculate two-point correlation functions of color-singlet and octet quark-anti-quark operators. We find long range order in the standard $<\barψψ>$ channel,

Luca Barbieri-Viale, Andreas Rosenschon, Morihiko Saito

We reformulate a conjecture of Deligne on 1-motives by using the integral weight filtration of Gillet and Soulé on cohomology, and prove it. This implies the original conjecture up to isogeny. If the degree of cohomology is at most two, we can prove the conjecture for the Hodge realization without isogeny, and even for 1-motives with torsion.

Leonardo Rastelli, Ashoke Sen, Barton Zwiebach

In a previous paper [hep-th/0012251] we proposed a simple class of actions for string field theory around the tachyon vacuum. In this paper we search for classical solutions describing D-branes of different dimensions using the ansatz that the solutions factorize into the direct product of a matter state and a universal ghost state. We find closed form expre

Adam Ritz, Arkady Vainshtein

We consider the long range forces between two BPS particles on the Coulomb branch of N=2 and N=4 supersymmetric gauge theories. The 1/r potential is unambiguously fixed, even at strong coupling, by the moduli dependence of central charges supported by the BPS states. The effective Coulombic coupling vanishes on marginal stability curves, while sign changes o

Michael Haack, Jan Louis, Harvendra Singh

In this paper we study K3 compactification of ten-dimensional massive type IIA theory with all possible Ramond-Ramond background fluxes turned on. The resulting six-dimensional theory is a new massive (gauged) supergravity with an action that is manifestly invariant under an O(4,20) / (O(4) times O(20)) duality symmetry. We discover that this six-dimensional

David Vitali, Stefano Mancini, Paolo Tombesi

We show that a cooling scheme and an appropriate quantum nonstationary strategy can be used to improve the signal to noise ratio for the optomechanical detection of weak impulsive forces.

Kingman Cheung

The recent measurement on the muon anomalous magnetic moment $a_\mu$ shows a $2.6\sigma$ deviation from the standard model value. We show that it puts an interesting bound on the mass of the second generation leptoquarks. To account for the data the leptoquark must have both the left- and right-handed couplings to the muon. Assuming that the couplings have e

B. I. Lev, A. A. Semenov, C. V. Usenko

A description of scalar charged particles, based on the Feshbach-Villars formalism, is proposed. Particles are described by an object that is a Wigner function in usual coordinates and momenta and a density matrix in the charge variable. It is possible to introduce the usual Wigner function for a large class of dynamical variables. Such an approach explicitl

Mun-Seog Kim, C. U. Jung, Min-Seok Park, S. Y. Lee

We report the magnetic-field dependence of the irreversible magnetization of the recently discovered binary superconductor MgB$_{2}$. For the temperature region of $T< 0.9T_c$, the contribution of the bulk pinning to the magnetization overwhelms that of the surface pinning. This was evident from the fact that the magnetization curves, $M(H)$, were well descr

Sofiane Tafat

We study nonperturbative corrections to the transverse momentum distribution of vector bosons in the Drell-Yan process. Factorizing out the Sudakov effects due to soft gluons we express their contribution to the distribution in the form of the vacuum averaged Wilson loop operator. We calculate the nonperturbative contribution to the Sudakov form factor using

W. N. Kang, C. U. Jung, Kijoon H. P. Kim, Min-Seok Park

The longitudinal resistivity rho_{xx} and Hall coefficient R_H were measured for MgB2 sintered under high pressure. We found that R_H is positive like cuprate high-Tc superconductors, and decreases as the temperature increases for 40 K < T < 300 K. The cotangent of the Hall angle was found to follow a+bT^2 behavior from Tc to 300 K. At T = 100 K, R_H = 4.1 x

P. Bantay

It is shown that for the modular representations associated to Rational Conformal Field Theories, the kernel is a congruence subgroup whose level equals the order of the Dehn-twist. An explicit algebraic characterization of the kernel is given. It is also shown that the conductor, i.e. the order of the Dehn-twist is bounded by a function of the number of pri

S. Antoci, D. -E. Liebscher

We analyse the Schwarzschild solution in the context of the historical development of its present use, and explain the invariant definition of a singular surface at the Schwarzschild&#39;s radius, that can be applied to the Kerr-Newman solution too.

Thomas Nowotny, Ulrich Behn

The local magnetization in the one-dimensional random-field Ising model is essentially the sum of two effective fields with multifractal probability measure. The probability measure of the local magnetization is thus the convolution of two multifractals. In this paper we prove relations between the multifractal properties of two measures and the multifractal

Felix Finster, Oliver C. Schnuerer

We prove an existence theorem for convex hypersurfaces of prescribed Gauss curvature in the complement of a compact set in Euclidean space which are close to a cone.

C. Bizdadea, M. T. Miauta, S. O. Saliu

Consistent couplings between an Abelian gauge field and three types of matter fields are investigated by means of the Hamiltonian BRST deformation theory based on cohomological techniques. In this manner, scalar electrodynamics, the Stuckelberg theory for Abelian zero- and one-forms, respectively, spinor electrodynamics, are inferred.

Francesco Vissani

We study the class of neutrino mass matrices with a dominant block but unspecified O(1) coefficients, and scan the possible models by the help of random number generators. We discuss which are the most common expectations in dependence of the adjustable parameter of the mass matrices, &#34;epsilon&#34;, and emphasise an interesting sub-class of models that h

Paolo Creminelli, Giovanni Signorelli, Alessandro Strumia

The solar neutrino data are analyzed in a frequentist framework, using the Crow-Gardner and Feldman-Cousins prescriptions for the construction of confidence regions. Including in the fit only the total rates measured by the various experiments, both methods give results similar to the commonly used Delta chi^2-cut approximation. When fitting the full data se

Stefan Neuwirth

We characterize the 1-unconditional subsequences of the canonical basis (e_rc) of elementary matrices in the Schatten-von-Neumann class S^p . The set I of couples (r,c) must be the set of edges of a bipartite graph without cycles of even length 4<=l<=p if p is an even integer, and without cycles at all if p is a positive real number that is not an even integ

C. Bauer, H. S. Do

We present a new algorithm for the reduction of one-loop tensor Feynman integrals within the framework of the XLOOPS project, covering both mathematical and programming aspects. The new algorithm supplies a clean way to reduce the one-loop one-, two- and three-point Feynman integrals with arbitrary tensor rank and powers of the propagators to a basis of simp

T. Hirayama

The energy-momentum tensor of the Liénard-Wiechert field is split into bound and emitted parts in the Rindler frame, by generalizing the reasoning of Teitelboim applied in the inertial frame. Our analysis proceeds by invoking the concept of ``energy&#39;&#39; defined with respect to the Killing vector field attached to the frame. We obtain the radiation form

Teruyuki Kitabayashi, Masaki Yasue

An SU(3)_L x U(1)_N gauge model, where E^{-i} (i=1,2,3) as heavy leptons are placed in the third member of lepton triplets, is shown to provide the large mixing angle (LMA) MSW solution to the solar neutrino problem. By introducing approximate conservation of L_e-L_mu-L_tau (\equiv L&#39;) into the model, we have estimated Δm_\odot^2 \sim \sqrt{2}εΔm_{atm}^2

P. M. Lavrov, P. Yu. Moshin

We consider possible superfield representations of extended BRST symmetry for general gauge theories within the principle of gauge-fixing based on a generating equation for the gauge functional. We examine admissible superfield choices for an extended antibracket and delta-operator with given algebraic properties and show that only one of these choices is co

Michael Levitin, Leonid Parnovski

Using simple commutator relations, we obtain several trace identities involving eigenvalues and eigenfunctions of an abstract self-adjoint operator acting in a Hilbert space. Applications involve abstract universal estimates for the eigenvalue gaps. As particular examples, we present simple proofs of the classical universal estimates for eigenvalues of the D

Amos Sharoni, Israel Felner, Oded Millo

Cryogenic scanning tunneling microscopy and magnetization measurements were used to study the superconducting properties of MgB_2. The magnetization measurements show a sharp superconductor transition onset at T_c = 38.5 K, in agreement with previous works. The tunneling spectra exhibit BCS gap structures, with gap parameters in the range of 5 to 7 meV, yiel

Alexei Nurmagambetov

We consider the T-duality transformations of the low-energy quantum string theory effective action in the presence of classical fundamental string source and demonstrate explicitly that T-duality still holds.

S. V. Borisenko, A. A. Kordyuk, S. Legner, C. Duerr

The strong dependence of the momentum distribution of the photoelectrons on experimental conditions raises the question as to whether angle-resolved photoemission spectroscopy (ARPES) is able to provide an accurate reflection of the Fermi surface in Bi-based cuprate superconductors. In this paper we experimentally prove that the main contribution to the inte

Thomas Friedrich, Stefan Ivanov

We describe all almost contact metric, almost hermitian and $G_2$-structures admitting a connection with totally skew-symmetric torsion tensor, and prove that there exists at most one such connection. We investigate its torsion form, its Ricci tensor, the Dirac operator and the $\nabla$-parallel spinors. In particular, we obtain solutions of the type II stri

Xin-Nian Wang, Xiaofeng Guo

Multiple parton scattering and induced parton energy loss is studied in deeply inelastic scattering (DIS) off nuclei. The effect of multiple scattering of a highly off-shell quark and the induced parton energy loss is expressed in terms of the modification to the quark fragmentation functions. We derive such modified quark fragmentation functions and their Q

Rong-Gen Cai

In a recent paper hep-th/0008140 by E. Verlinde, an interesting formula has been put forward, which relates the entropy of a conformal formal field in arbitrary dimensions to its total energy and Casimir energy. This formula has been shown to hold for the conformal field theories that have AdS duals in the cases of AdS Schwarzschild black holes and AdS Kerr

S. X. Dou, X. L. Wang, J. Horvat, D. Milliken

The recent discovery of intermediate-temperature superconductivity (ITC) in MgB2 by Akimitsu et al. and its almost simultaneous explanation in terms of a hole-carrier-based pairing mechanism by Hirsch, has triggered an avalanche of studies of its structural, magnetic and transport properties. As a further contribution to the field we report the results of fi

V. Vedral

Quantum mechanics and information theory are among the most important scientific discoveries of the last century. Although these two areas initially developed separately it has emerged that they are in fact intimately related. In this review I will show how quantum information theory extends traditional information theory by exploring the limits imposed by q

B. Bagchi, S. Mallik, C. Quesne

In the framework of SUSYQM extended to deal with non-Hermitian Hamiltonians, we analyze three sets of complex potentials with real spectra, recently derived by a potential algebraic approach based upon the complex Lie algebra sl(2, C). This extends to the complex domain the well-known relationship between SUSYQM and potential algebras for Hermitian Hamiltoni

D. J. Fernandez C., H. C. Rosu

We generalize the standard first-order intertwining relationship of supersymmetric quantum mechanics in order to include simultaneous scaling transformations in both the original Hamiltonian and the intertwining operator. It is argued that in this way one can generate potentials with more interesting spectra than those obtained by means of the standard first

J. Knoll, Yu. B. Ivanov, D. N. Voskresensky

It is shown that the Kadanoff-Baym equations at consistent first-order gradient approximation reveal exact rather than approximate conservation laws related to global symmetries of the system. The conserved currents and energy-momentum tensor coincide with corresponding Noether quantities in the local approximation. These exact conservations are valid, provi

Michael Murray

A summary of current interferometry data in relativistic heavy ions is presented. At sqrt{s}=17GeV a sudden increase in the pion source volume is observed for central PbPb collisions. This seems to imply that the pion phase density has reached a limit. The source size of different particles decreases with mass when the transverse velocity is held constant bu

M. Rousseau, C. Beck, C. Bhattacharya, V. Rauch

The possible occurence of highly deformed configurations is investigated in the $^{40}$Ca and $^{56}$Ni di-nuclear systems as formed in the $^{28}$Si + $^{12}$C and $^{28}$Si + $^{28}$Si reactions, respectively, by using the properties of emitted light charged particles. Inclusive as well as exclusive data of the heavy fragments (A $\geq$ 6) and their associ

G. Boffetta, G. Lacorata, G. Redaelli, A. Vulpiani

We review and discuss some different techniques for describing local dispersion properties in fluids. A recent Lagrangian diagnostics, based on the Finite Scale Lyapunov Exponent (FSLE), is presented and compared to the Finite Time Lyapunov Exponent (FTLE), and to the Okubo-Weiss (OW) and Hua-Klein (HK) criteria. We show that the OW and HK are a limiting cas

Kazuhiro Hikami

Studied is the Baxter equation for the quantum discrete Boussinesq equation. We explicitly construct the Baxter $\mathcal{Q}$ operator from a generating function of the local integrals of motion of the affine Toda lattice field theory, and show that it solves the third order operator-valued difference equation.

Sami I. Muslih

The link between the tratment of singular Lagrangians as field systems and the canonical Hamiltonian approach is studied. It is shown that the singular Lagrangians as field systems are always in exact agreement with the canonical approach for the parametrization invariant theories.

A. Dranishnikov

We develop some basic Lipschitz homotopy technique and apply it to manifolds with finite asymptotic dimension. In particular we show that the Higson compactification of a uniformly contractible manifold is mod $p$ acyclic in the finite dimensional case. Then we give an alternative proof of the Higher Signature Novikov Conjecture for the groups with finite as

B. Khesin, A. Rosly

We describe polar homology groups for complex manifolds. The polar k-chains are subvarieties of complex dimension k with meromorphic forms on them, while the boundary operator is defined by taking the polar divisor and the Poincare residue on it. The polar homology groups may be regarded as holomorphic analogues of the homology groups in topology. We also de

Stefan Neuwirth

We solve an elementary extremal problem on trigonometric polynomials and obtain the exact value of the Sidon constant for sets with three elements {n0, n1, n2}: it is \sec(π/ 2n) for n = max(n1-n0, n2-n0, n2-n1) / gcd(n1-n0, n2-n0).

M. R. Razvan, M. Fotouhi Firoozabad

In this paper, we use Conley index theory to examine the Poincare index of an isolated invariant set. We obtain some limiting conditions on a critical point of a planar vector field to be an isolated invariant set. As a result we show the existence of infinitely many homoclinic orbits for a critical point with the Poincare index greater than one.

Ruslan Sharipov

Problem of global integration of geometric structures arising in the theory of dynamical systems admitting the normal shift is considered. In the case when such integration is possible the problem of globalization for shift maps is studied.

Grigori Shpiz

This paper suggests an algebraic version of the theorem on the existence of eigenvectors for linear operators in abstract idempotent spaces. Earlier, the theorem on the existence of eigenvectors was only known for the cases of a free finite-dimensional semimodule and for compact operators in semimodules of real continuous functions.

Benson Farb, John Franks

This paper has been withdrawn by the authors; it will be incorporated into part I of the series (in preparation).

Anna Erschler-Dyubina

We prove that there exist infinitely many asymptotics of drift for random walks on finitely generated groups.

Tim R. Morris

A gauge invariant Wilsonian effective action is constructed for pure SU(N) Yang-Mills theory by formulating the corresponding flow equation. Manifestly gauge invariant calculations can be performed i.e. without gauge fixing or ghosts. Regularisation is implemented in a novel way which realises a spontaneously broken SU(N|N) supergauge theory. As an example w

Hikoya Kasari, Yoshio Yamaguchi

Contrary to the conventional belief, it was shown that the Breit equation has the eigenvalues for bound states of two oppositely charged Dirac particles interacting through the (static) Coulomb potential. All eigenvalues reduced to those of the Schödinger case in the non-relativistic limit.

C. Bizdadea, E. M. Cioroianu, S. O. Saliu

An irreducible Hamiltonian BRST-anti-BRST treatment of reducible first-class systems based on homological arguments is proposed. The general formalism is exemplified on the Freedman-Townsend model.

N. Chepilko, A. Romanenko

Using extended Schwinger&#39;s quantization approach quantum mechanics on a Riemannian manifold $M$ with a given action of an intransitive group of isometries is developed. It was shown that quantum mechanics can be determined unequivocally only on submanifolds of $M$ where $G$ acts simply transitively (orbits of $G$-action). The remaining part of degrees of

N. Chepilko, A. Romanenko

Extended Schwinger&#39;s quantization procedure is used for constructing quantum mechanics on a manifold with a group structure. The considered manifold $M$ is a homogeneous Riemannian space with the given action of isometry transformation group. Using the identification of $M$ with the quotient space $G/H$, where $H$ is the isotropy group of an arbitrary fi

Je-An Gu, Pei-Ming Ho, Sanjaye Ramgoolam

In this paper we point out that the spacetime uncertainty relation proposed for string theory has strong cosmological implications that can solve the flatness problem and the horizon problem without the need of inflation. We make minimal assumptions about the very early universe.

M. B. Voloshin

The response to a magnetic flux is considered of the vacuum state of charged Dirac fermions interacting with a domain wall made of a neutral spinless field in (3+1) dimensions with the fermion mass having a phase variation across the wall. It is pointed out that due to simple C parity arguments the spontaneous magnetization for this system is necessarily zer

Francesco Vissani

The hypothesis that neutrinos are massive has a strong experimental support; however, the information we have is quite limited, and many possibilities are open. Theoretical considerations might help fill the gaps (or foresee regularities), as we illustrate with a specific example.

D. Bardin, P. Christova, L. Kalinovskaya, Giampiero Passarino

The atomic parity-violation (APV) parameter QW for a nucleus with `n&#39; neutrons and `z&#39; protons has been included in the list of pseudo-observables accessible with the codes TOPAZ0 and ZFITTER. In this way one can add the APV results in the LEP EWWG `global&#39; electroweak fits, checking the corresponding effect when added to the existing precision m

Patrik Eden

I discuss recent developments in the QCD cascade formalism. I focus on the importance of and uncertainties in higher order corrections to the Modified Leading Log approximation for final-state radiation. I also talk about the CCFM and LDC evolution equations for initial-state radiation in DIS.

G. Cvetic, D. Schildknecht, B. Surrow, M. Tentyukov

We give a detailed account of the recently formulated generalized vector dominance/colour-dipole picture (GVD/CDP) of deep-inelastic scattering at low $x\cong Q^2/W^2$, including photoproduction. The approach, based on $γ^*(q \bar q)$ transitions, $q \bar q$ propagation and diffractive $(q \bar q)p$ scattering via the generic structure of the two-gluon excha

HERMES Collaboration, A. Airapetian

Evidence for a positive longitudinal double-spin asymmetry <A_1^rho> = 0.24 +-0.11 (stat) +-0.02 (syst) in the cross section for exclusive diffractive rho^0(770) vector meson production in polarised lepton-proton scattering was observed by the HERMES experiment. The longitudinally polarised 27.56 GeV HERA positron beam was scattered off a longitudinally pola

H. E. Puthoff

Standard pedagogy treats topics in general relativity (GR) in terms of tensor formulations in curved space-time. Although mathematically straightforward, the curved space-time approach can seem abstruse to beginning students due to the degree of mathematical sophistication required. As a heuristic tool to provide insight into what is meant by a curved metric

Christian Klein

This is the first in a series of papers on the construction of explicit solutions to the stationary axisymmetric Einstein equations which describe counter-rotating disks of dust. These disks can serve as models for certain galaxies and accretion disks in astrophysics. We review the Newtonian theory for disks using Riemann-Hilbert methods which can be extende

Wu Shuang-Qing, Cai Xu

Hawking effect of Dirac particles in a variable-mass Kerr space-time is investigated by using method of the generalized tortoise coordinate transformation. The location and the temperature of event horizon of the non-stationary Kerr black hole are derived. It is shown that the temperature and the shape of event horizon depend not only on the time but also on

Tsukasa Murata, Keiji Tsunoda, Kazuhiro Yamamoto

Motivated by a recent work by Terashima (Phys. Rev. D60 084001), we revisit the fluctuation-dissipation (FD) relation between the dissipative coefficient of a detector and the vacuum noise of fields in curved spacetime. In an explicit manner we show that the dissipative coefficient obtained from classical equations of motion of the detector and the scalar (o

Christian Klein

This is the second in a series of papers on the construction of explicit solutions to the stationary axisymmetric Einstein equations which can be interpreted as counter-rotating disks of dust. We discuss the class of solutions to the Einstein equations for disks with constant angular velocity and constant relative density which was constructed in the first p

Daniel M. Sforza

Finite dimensional models that mimic the constraint structure of Einstein&#39;s General Relativity are quantized in the framework of BRST and Dirac&#39;s canonical formalisms. The first system to be studied is one featuring a constraint quadratic in the momenta (the &#34;super-Hamiltonian&#34;) and a set of constraints linear in the momenta (the &#34;supermo

Joerg Flum, Martin Grohe

In this article, we study parameterized complexity theory from the perspective of logic, or more specifically, descriptive complexity theory. We propose to consider parameterized model-checking problems for various fragments of first-order logic as generic parameterized problems and show how this approach can be useful in studying both fixed-parameter tracta

Patrizia Vignolo, Anna Minguzzi, M. P. Tosi

We evaluate the scattering functions of a gas of spin-polarized, non-interacting fermions confined in a quasi-onedimensional harmonic trap at zero temperature. The main focus is on the inelastic scattering spectrum and on the angular distribution of scattered light from a mesoscopic atomic cloud as probes of its discrete quantum levels and of its shell struc