April 2000 arXiv papers — page 22

Eiji Ogasa

Let K and K' be 2-knots. Suppose that K and K' are ribbon-move equivalent. Then the Farber-Levine pairing for K is equivalent to that for K' and the (Z-)torsion part of the first Alexander module of $K$ is isomorphic to that of K' as Z[Z] modules. Let K be a 2-knot which is ribbon-move equivalent to the trivial knot. Then the Atiyah-Patodi-Si

Jihn E. Kim, Bumseok Kyae, Hyun Min Lee

The Gauss-Bonnet interaction is the only consistent quadratic interaction below the Planck scale in the Randall-Sundrum compactification. We study various static and inflationary solutions including this Gauss-Bonnet interaction.

S. N. Balaban, E. P. Pokatilov, V. M. Fomin, V. N. Gladilin

A model is developed for a detailed investigation of the current flowing through a cylindrical nanosize MOSFET with a close gate electrode. The quantum mechanical features of the lateral charge transport are described by Wigner distribution function which is explicitly dealing with electron scattering due to acoustic phonons and acceptor impurities. A numeri

Emiliano Papa, Alexei M. Tsvelik

We study a single-particle density of states (DOS) in a model of Tomonaga-Luttinger liquid with small (large) values of the Luttinger parameter $K_\rc < 0.17$, ($K_\rc > 5.82$), in the charge sector. We explain that such values of $K_\rc$ may be achieved by electron-phonon interactions without generating the spin gap. We suggest that electron-phonon interact

D. Sornette

Firm foundation theory estimates a security&#39;s firm fundamental value based on four determinants: expected growth rate, expected dividend payout, the market interest rate and the degree of risk. In contrast, other views of decision-making in the stock market, using alternatives such as human psychology and behavior, bounded rationality, agent-based modeli

Eri Asakawa, Isamu Watanabe, Akio Sugamoto

In the $s$-channel Higgs-boson-exchange processes, the interference between the amplitudes for CP-even and CP-odd Higgs bosons is sizable, if the helicities of initial and final particles are properly fixed and if the mass difference between these bosons is not much larger than their decay widths. We discuss this interference effect in the process $μ^+ μ^-$

Volker D. Burkert

Applications of the chiral expansion to generalize the Gerasimov-Drell-Hearn sum rule for finite $Q^2$ are discussed. The observation of several authors that the corrections to the leading order contributions are large and limit the applicability to a very small range in $Q^2$, are valid when considering the sum rule for protons and neutrons, separately. Whe

I. V. Arzhantsev, D. A. Timashev

Let G be a reductive algebraic group and let H be a reductive subgroup of G. We describe all pairs (G,H) such that for any affine G-variety X with a dense G-orbit isomorphic to G/H the number of G-orbits in X is finite. The maximal number of parameters in families of G-orbits in all affine embeddings of G/H is computed.

Yong-Yeon Keum, Hsiang-nan Li, A. I. Sanda

We evaluate $B\to Kπ$ decay amplitudes in perturbative QCD picture. It is found that penguin contributions are dynamically enhanced by nearly 50% compared to those assumed in the factorization approximation. It is also shown that annihilation diagrams are not negligible, and give large strong phases. Our results for branching ratios of $B\to Kπ$ decays for a

Shahar Hod

We present some arguments in support of a {\it zero} entropy for {\it extremal} black holes. These rely on a combination of both quantum, thermodynamic, and statistical physics arguments. This result may shed some light on the nature of these extreme objects. In addition, we show that within a {\it quantum} framework the capture of a particle by an initially

David Brown

A rapidly rotating, axisymmetric star can be dynamically unstable to an m=2 &#34;bar&#34; mode that transforms the star from a disk shape to an elongated bar. The fate of such a bar-shaped star is uncertain. Some previous numerical studies indicate that the bar is short lived, lasting for only a few bar-rotation periods, while other studies suggest that the

Jun-Chen Su

The Lorentz-covariant quantization performed in the Hamiltonian path-integral formalism for massless non-Abelian gauge fields has been achieved. In this quantization, the Lorentz condition, as a constraint, must be introduced initially and incorporated into the Yang-Mills Lagrangian by the Lagrange undetermined multiplier method. In this way, it is found tha

Peng Zhou, S. Swain, L. You

We study the Autler-Townes spectrum of a V-type atom coupled to a single-mode, frequency-tunable cavity field at finite termperature, with a pre-selected polarization in the bad cavity limit, and show that, when the mean number of thermal photons $N\gg 1$ and the excited sublevel splitting is very large (the same order as the cavity linewidth), the probe gai

B. G. Sidharth

We argue that dimensionality is not absolute, but that it depends on the scale of resolution, from the Planck to the macro scale.

B. G. Sidharth

In an earlier paper we had pointed out that Quantum Mechanical type effects are seen at different scales in the macro universe also. In this paper we obtain a rationale for this, which lies in the picture of bound material systems, spanning a Compton wavelength type extent, separated by much larger and relatively much less dense distances.

B. G. Sidharth

In this brief note we re-emphasize the fact that an underpinning of fluctuations characterizes the fundamental interactions in the light of El Naschie&#39;s recent work.

B. G. Sidharth

In this talk, we touch upon the chaotic and fractal aspects of the Universe.

Mircea Crâşmăreanu

Some types of first integrals for Hamiltonian Nambu-Poisson vector fields are obtained by using the notions of pseudosymmetries. In this theory, the homogeneous Hamiltonian vector fields play a special role and we point out this fact. The differential system which describe the $SU(2)$-monopoles is given as example. The paper ends with two appendices.

Maciej Blaszak

A review of a new separability theory based on degenerated Poisson pencils and the so-called separation curves is presented. This theory can be considered as an alternative to the Sklyanin theory based on Lax representations and the so-called spectral curves.

G. Falkovich, I. Kolokolov, V. Lebedev, S. Turitsyn

We present a consistent method to calculate the probability distribution of soliton parameters in systems with additive noise. Even though a weak noise is considered, we are interested in probabilities of large fluctuations (generally non-Gaussian) which are beyond perturbation theory. Our method is a further development of the instanton formalism (method of

Steve Shkoller

This paper is devoted to the geometric analysis of the incompressible averaged Euler equations on compact Riemannian manifolds with boundary. The equation also coincides with the model for a second-grade non-Newtonian fluid. We study the analytical and geometrical properties of the Lagrangian flow map. We prove existence and uniqueness of smooth-in-time solu

Boris A. Kupershmidt

This is a review of the 5-volumes of Ramanujan&#39;s Notebooks, as worked over by Bruce C. Berndt over the last quarter of the XX-th Century. To illustrate how useful Ramanujan&#39;s insights could be for anyone who indulges in the wild pleasure of savoring Ramanujan&#39;s genius, the reviewer takes one formula of Ramanujan from the Notebooks, analyses it ca

Boris A. Kupershmidt

A counter-intuitive result of Gauss (formulae (1.6), (1.7) below) is made less mysterious by virtue of being generalized through the introduction of an additional parameter.

Dimitry Leites, Alexander Shapovalov

Following V. Drinfeld and G. Olshansky, we construct Manin triples $(\fg, \fa, \fa^*)$ such that $\fg$ is different from Drinfeld&#39;s doubles of $\fa$ for several series of Lie superalgebras $\fa$ which have no even invariant bilinear form (periplectic, Poisson and contact) and for a remarkable exception. Straightforward superization of suitable Etingof--K

Yuri A. Ilyin

We consider the class of autonomous systems $\dot x=f(x)$, where $x \in {\bf R}^{2n}$, $f \in C^1({\bf R}^{2n})$ whose phase portrait is a Cartesian product of $n$ two-dimensional {\em centres}. We also consider perturbations of this system, namely $\dot x=f(x)+g(t,x)$, where $g \in C^1({\bf R}\times{\bf R}^{2n})$ and $g$ is asymptotically small, that is $g\

Björn Birnir, Nils Svanstedt

The Navier-Stokes equation driven by heat conduction is studied. As a prototype we consider Rayleigh-Bénard convection, in the Boussinesq approximation. Under a large aspect ratio assumption, which is the case in Rayleigh-Bénard experiments with Prandtl number close to one, we prove the existence of a global strong solution to the 3D Navier-Stokes equation c

Yongge Tian

We present in this paper some fundamental tools for developing matrix analysis over the complex quaternion algebra. As applications, we consider generalized inverses, eigenvalues and eigenvectors, similarity, determinants of complex quaternion matrices, and so on.

Wolfgang Buehring

An asymptotic expansion of a ratio of products of gamma functions is derived. It generalizes a formula which was stated by Dingle, first proved by Paris, and recently reconsidered by Olver.

Yongge Tian

As is well-known, the real quaternion division algebra $ {\cal H}$ is algebraically isomorphic to a 4-by-4 real matrix algebra. But the real division octonion algebra ${\cal O}$ can not be algebraically isomorphic to any matrix algebras over the real number field ${\cal R}$, because ${\cal O}$ is a non-associative algebra over ${\cal R}$. However since ${\ca

H. B. Benaoum

BFYM on commutative and noncommutative ${\mathbb{R}}^4$ is considered and a Seiberg-Witten gauge-equivalent transformation is constructed for these theories. Then we write the noncommutative action in terms of the ordinary fields and show that it is equivalent to the ordinary action up to higher dimensional gauge invariant terms.

Dean Lee

We review recent developments in non-perturbative field theory using modal field methods. We discuss Monte Carlo results as well as a new diagonalization technique known as the quasi-sparse eigenvector method.

J. Smith

We compare variable number schemes for heavy quark electroproduction

G. S. Sharov

For the relativistic string with massive ends (the meson model) and four various string baryon models (q-qq, q-q-q, Y and $Δ$) we consider the classical quasirotational motions, which are small disturbances of the planar uniform rotations of these systems. For the string meson model the two types of these solutions are obtained. They describe oscillatory mot

S. Arunagiri

I review the role of the spectator quarks effect in the inclusive beauty decays. The evaluation of the expectation values of four-quark operators between hadronic states and its consequences are discussed.

Jie-Jie Zhu, Mu-Lin Yan

We propose to search for CP-violating effects in the decay psi(2S)->J/psi+pi+pi. The scheme has the advantage that one does not need to track two or more CP-conjugate processes. Model independent amplitudes are derived for this purpose. The fact that leading CP violating terms are O(k) under low energy expansion and the processes are flavor disconnected make

Ting-Wai Chiu

We show that even if a lattice Dirac operator satisfies the conditions consisting of locality, free of species doublings, correct continuum behavior, $\gm5$-hermiticity and the Ginsparg-Wilson relation, it does not necessarily have exact zero modes in nontrivial gauge backgrounds. This implies that each lattice Dirac operator has its own topological characte

I. L. Bogolubsky, V. K. Mitrjushkin, M. Muller-Preussker, P. Peter

The Gribov ambiguity problem is studied for compact lattice QED within the Lorentz gauge. In the Coulomb phase, Gribov copies are mainly caused by double Dirac sheets and zero-momentum modes of the gauge fields. Removing them by (non-) periodic gauge transformations allows to reach the absolute extremum of the Lorentz gauge functional. For standard Lorentz g

Jens C. Niemeyer, Raphael Bousso

We investigate the quantum evolution of large black holes that nucleate spontaneously in de Sitter space. By numerical computation in the s-wave and one-loop approximations, we verify claims that such black holes can initially &#34;anti-evaporate&#34; instead of shrink. We show, however, that this is a transitory effect. It is followed by an evaporating phas

Arthur Lue, Erick J. Weinberg

One of the remarkable features of black holes is that they possess a thermodynamic description, even though they do not appear to be statistical systems. We use self-gravitating magnetic monopole solutions as tools for understanding the emergence of this description as one goes from an ordinary spacetime to one containing a black hole. We describe how causal

M. Farine, P. Schuck, X. Vinas

The moment of inertia Q of a trapped superfluid gas of atomic Fermions (6Li) is calculated as a function of the temperature. At zero temperature the moment of inertia takes on the irrotational flow value. Only for T very close to Tc rigid rotation is attained. It is proposed that future measurements of the rotational energy will unambiguously reveal whether

Gilles Poirot

With the help of computer algebra, I devise an exact unitary transformation for the Anderson impurity model which allows to kill the hybridization term in the slightly simplified case of zero chemical potential. Then I compute explicitly the outcome of this transformation. This is a rigorous version of the well known Schrieffer-Wolff transformation. It shoul

Alexander Moroz, Adriaan Tip, Jean-Michel Combes

Photonic band structure of metal-dielectric and semiconductor-dielectric layered structures are studied in the presence of a strong absorption. It is shown that absorption can enlarge some gaps by as much as 50%.

R. Botet, M. Ploszajczak

We discuss the universal scaling laws of order parameter fluctuations in any system in which the second-order critical behaviour can be identified. These scaling laws can be derived rigorously for equilibrium systems when combined with the finite-size scaling analysis. The relation between order parameter, criticality and scaling law of fluctuations has been

Igor V. Igumenshchev, Marek A. Abramowicz, Ramesh Narayan

Advection-dominated accretion flows (ADAFs) are known to be convectively unstable for low values of the viscosity parameter alpha. Two-dimensional axisymmetric hydrodynamic simulations of such flows reveal a radial density profile which is significantly flatter than the rho~r^{-3/2} expected for a canonical ADAF. The modified density profile is the result of

Katherine Blundell, Namir Kassim, Rick Perley

Low-radio-frequency observations played a remarkable role in the early days of radio astronomy; however, in the subsequent three or four decades their usefulness has largely been in terms of the finding-frequency of surveys. Recent technical innovation at the VLA has meant that spatially well-resolved imaging at low frequencies is now possible. Such imaging

Akika Nakamichi, Izumi Joichi, Osamu Iguchi, Masahiro Morikawa

Large-scale astrophysical systems are non-extensive due to their long-range force of gravity. Here we show an approach toward the statistical mechanics of such self-gravitating systems (SGS). This is a generalization of the standard statistical mechanics based on the new definition of entropy; Tsallis statistical mechanics. Developing the composition of entr

Elena Pierpaoli, Douglas Scott, Martin White

The Universe could be spatially flat, positively curved or negatively curved. Each option has been popular at various times, partly affected by an understanding that models tend to evolve away from flatness. The curvature of the Universe is amenable to measurement, through tests such as the determination of the angles of sufficiently large triangles. The ang