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Sep 22, 2013
09/13
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Stavros Mouslopoulos; Antonios Papazoglou
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We explore the phenomenology of the recently proposed "+-+" brane model which has a characteristic anomalously light first Kaluza-Klein mode. We consider the processes e^+ e^- to mu^+ mu^- and the Kaluza-Klein production e^+ e^- to gamma KK giving missing visible energy. These in combination with the latest Cavendish experiments place severe bounds on the parameter space of the model. We also discuss how forthcoming experiments can test the model for ``natural'' range of the...
Source: http://arxiv.org/abs/hep-ph/0003207v3
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Sep 19, 2013
09/13
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Domenico Giulini; Norbert Straumann
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On December 14. 1900, Max Planck communicated his derivation of his radiation formula, which he later called ``an act of desperation''. This date is widely recognized as birthday of quantum theory. For Planck it meant the end of his carefully planned and ambitious research project, in which he wanted to establish the second law of thermodynamics as strictly deterministic law for systems of matter and electromagnetic radiation in interaction. He knew he could not succeed within classical...
Source: http://arxiv.org/abs/quant-ph/0010008v1
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Sep 18, 2013
09/13
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J. R. Mureika
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A simple algebraic expression is presented to correct men's and women's 100 metre sprint times for ambient wind and altitude effects. The simplified formula is derived from a more complicated equation of motion used to model the athlete's velocity as a function of time (the velocity curve). This method predicts adjustments to 0-wind and 0-altitude equivalents, which are in excellent agreement to other estimates presented in the literature. The expression is easily programmable on any computer,...
Source: http://arxiv.org/abs/physics/0006057v1
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Jul 20, 2013
07/13
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A. Prigent; O. Dauchot
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Investigations of counter-rotating Taylor-Couette flow (TCF) in the narrow gap limit are conducted in a very large aspect ratio apparatus. The phase diagram is presented and compared to that obtained by Andereck et al. The spiral turbulence regime is studied by varying both internal and external Reynolds numbers. Spiral turbulence is shown to emerge from the fully turbulent regime via a continuous transition appearing first as a modulated turbulent state, which eventually relaxes locally to the...
Source: http://arxiv.org/abs/cond-mat/0009241v1
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Sep 22, 2013
09/13
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M. Cocchi; A. Bazzano; L. Natalucci; P. Ubertini; J. Heise; J. J. M. in 't Zand; J. M. Muller; M. J. S. Smith
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We report on the long term monitoring of the GINGA transient source GS 1826-238 performed with the BeppoSAX Wide Fiels Camera (WFC) instrument, during four different observing campaigns covering October 1996 - September 1999. WFC detection of type-I bursting activity from the source ruled out its proposed black hole candidacy and clearly suggested the compact object related to GS 1826-238 to be a weakly magnetized neutron star. The analysis of the arrival times of the observed 78 bursts lead to...
Source: http://arxiv.org/abs/astro-ph/0003331v1
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Sep 22, 2013
09/13
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M. Molotskii; V. Fleurov
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An anomalously strong volume magnetostriction in Invars may lead to a situation when at low temperatures the dislocation free energy becomes negative and a multiple generation of dislocations becomes possible. This generation induces a first order phase transition from the FCC crystalline to an amorphous state, and may be called "cold melting". The possibility of the cold melting in Invars is connected with the fact that the exchange energy contribution into the dislocation self...
Source: http://arxiv.org/abs/cond-mat/0011158v2
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Sep 19, 2013
09/13
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B. L. Altshuler; V. V. Flambaum; M. Yu. Kuchiev; V. G. Zelevinsky
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We suggest a ``ping-pong'' mechanism of enhancement for fusion reactions between a low energy external deuteron beam and the deuterons in a condensed matter or molecular target. The mechanism is based on the possibility of acceleration of a target deuteron by the Coulomb field of a projectile deuteron with its subsequent rebound from a heavy atom in matter and the following fusion of the two deuterons moving towards each other. This effectively converts the fixed target process into a colliding...
Source: http://arxiv.org/abs/nucl-th/0010028v1
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Sep 18, 2013
09/13
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A. R. Champneys; B. A. Malomed; J. Yang; D. J. Kaup
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It is commonly held that a necessary condition for the existence of solitons in nonlinear-wave systems is that the soliton's frequency (spatial or temporal) must not fall into the continuous spectrum of radiation modes. However, this is not always true. We present a new class of {\it % codimension-one} solitons (i.e., those existing at isolated frequency values) that are {\em embedded} into the continuous spectrum. This is possible if the spectrum of the linearized system has (at least) two...
Source: http://arxiv.org/abs/nlin/0005056v1
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Sep 17, 2013
09/13
by
S. Sultansoy
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The first Part contains the invited talk given at the First International Workshop on Linac-Ring Type ep and $gamma$p Colliders (9-11 April 1997, Ankara, Turkey). Four known types of colliders, which may give an opportunity to achieve TeV center of mass energies in the near future (10-15 years), are discussed. Parameters of the linac-ring type e-p, $gamma$-p, e-nucleus and $gamma$-nucleus machines are roughly estimated. Some speculations on TeV scale physics are given. The physics goals of the...
Source: http://arxiv.org/abs/hep-ex/0007043v2
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Sep 22, 2013
09/13
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O. D. Chernavskaya; E. L. Feinberg; I. I. Royzen
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An approach is suggested, invoking vitally the notion of constituent massive quarks (valons) which can survive and propagate rather than hadrons (except of pions) within the hot and dense matter formed below the chiral transition temperature in course of the heavy ion collisions at high energies. This approach is shown to be quite good for description of the experimentally observed excess in dilepton yield at masses 250 MeV < M < 700 MeV over the prompt resonance decay mechanism (CERES...
Source: http://arxiv.org/abs/hep-ph/0011009v1
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Sep 19, 2013
09/13
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P. Grassberger; W. Nadler
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We describe a general strategy for sampling configurations from a given (Gibbs-Boltzmann or other) distribution. It is {\it not} based on the Metropolis concept of establishing a Markov process whose stationary state is the wanted distribution. Instead, it builds weighted instances according to a biased distribution. If the bias is optimal, all weights are equal and importance sampling is perfect. If not, "population control" is applied by cloning/killing configurations with too...
Source: http://arxiv.org/abs/cond-mat/0010265v1
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Sep 22, 2013
09/13
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Graeme Mitchison; Serge Massar
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Absorption-free (also known as ``interaction-free'') measurement aims to detect the presence of an opaque object using a test particle without that particle being absorbed by the object. Here we consider semi-transparent objects which have an amplitude $\alpha$ of transmitting a particle while leaving the state of the object unchanged and an amplitude $\beta$ of absorbing the particle. The task is to devise a protocol that can decide which of two known transmission amplitudes is present while...
Source: http://arxiv.org/abs/quant-ph/0003140v2
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Sep 18, 2013
09/13
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P. G. Silvestrov
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Non-Hermitean operators may appear during the calculation of a partition function in various models of statistical mechanics. The tail eigen-states, having anomalously small real part of energy $Re(\eps)$, became naturally important in this case. We consider the distribution of such states and the form of eigenfunctions for the particle propagating in an imaginary random potential (the model motivated by the statistics of polymer chains). Unlike it is in the Hermitean quantum mechanics, our...
Source: http://arxiv.org/abs/cond-mat/0008118v2
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Sep 19, 2013
09/13
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Armin Uhlmann
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For pairs, omega, rho, of density operators on a finite dimensional Hilbert space of dimension d I call k-fidelity the d - k smallest eigenvalues of | omega^1/2 rho^1/2 |. k-fidelities are jointly concave in omega, rho. This follows by representing them as infima over linear functions. For k = 0 known properties of fidelity and transition probability are reproduced. Partial fidelities characterize equivalence classes which are partially ordered in a natural way.
Source: http://arxiv.org/abs/quant-ph/9912114v2
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Sep 17, 2013
09/13
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V. V. Kassandrov; V. N. Trishin
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Foundations of algebrodynamics based on earlier proposed equations of biquaternionic holomorphy are briefly expounded. Free Maxwell and Yang-Mills Eqs. are satisfied identically on the solutions of primary system which is also related to the Eqs. of shear-free null congruences (SFC), and through them - to the Einstein-Maxwell electrovacuum system. Kerr theorem for SFC reduces the basic system to one algebraic equation, so that with each solution of the latter some (singular) solution of vacuum...
Source: http://arxiv.org/abs/gr-qc/0007026v1
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Sep 23, 2013
09/13
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Eldad Bettelheim; Oded Agam; Nadav M. Shnerb
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Diffusion limited reaction of the Lotka-Volterra type is analyzed taking into account the discrete nature of the reactants. In the continuum approximation, the dynamics is dominated by an elliptic fixed-point. This fixed-point becomes unstable due to discretization effects, a scenario similar to quantum phase transitions. As a result, the long-time asymptotic behavior of the system changes and the dynamics flows into a limit cycle. The results are verified by numerical simulations.
Source: http://arxiv.org/abs/cond-mat/9908450v4
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Sep 22, 2013
09/13
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D. Loison
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Classical XY spins on a two dimensional triangular lattice with antiferromagnetic interactions are reconsidered. We find that the Kosterlitz-Thouless transition associated to the U(1) symmetry appears at a temperature 0.0020(2) below the Ising transition at 0.5122(1) associated to the Z_2 symmetry. The Ising transition has critical exponents different from the standard ones. Using extensive Monte Carlo simulations for equilibrium and dynamical properties we show that the lack of universality...
Source: http://arxiv.org/abs/cond-mat/0001122v1
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Sep 22, 2013
09/13
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S. A. Crooker; N. Samarth; D. D. Awschalom
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Spin clustering in diluted magnetic semiconductors (DMS) arises from antiferromagnetic exchange between neighboring magnetic cations and is a strong function of reduced dimensionality. Epitaxially-grown single monolayers and abrupt interfaces of DMS are, however, never perfectly two-dimensional (2D) due to the unavoidable inter-monolayer mixing of atoms during growth. Thus the magnetization of DMS heterostructures, which is strongly modified by spin clustering, is intermediate between that of...
Source: http://arxiv.org/abs/cond-mat/0001378v1
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Sep 22, 2013
09/13
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Oded Agam; Boris L. Altshuler
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We consider the Faraday surface waves of a fluid in a container with a non-integrable boundary shape. We show that, at sufficiently low frequencies, the wave patterns are ``scars'' selected by the instability of the corresponding periodic orbits, the dissipation at the container side walls, and interaction effects which reflect the nonlinear nature of the Faraday waves. The results explain the observation of a limited number of scars with anomalous strengths in recent experiments by Kudrolli,...
Source: http://arxiv.org/abs/cond-mat/0004190v1
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Jul 20, 2013
07/13
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T. Dereli; O. Sarioglu
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We give a general class of exact solutions to the (1+2)-dimensional topologically massive gravity model coupled with Maxwell-Chern-Simons theory where a "self-duality" condition is imposed on the Maxwell field.
Source: http://arxiv.org/abs/gr-qc/0009090v1
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Jul 20, 2013
07/13
by
Zurab Kakushadze
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We consider an infinite-volume brane world setup where a codimension one brane is coupled to bulk gravity plus a scalar field with vanishing potential. The latter is protected by bulk supersymmetry, which is intact even if brane supersymmetry is completely broken as the volume of the extra dimension is infinite. Within this setup we discuss a flat solution with a ``self-tuning'' property, that is, such a solution exists for a continuous range of values for the brane tension. This...
Source: http://arxiv.org/abs/hep-th/0009199v2
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Sep 18, 2013
09/13
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A. M. Fedotov; N. B. Narozhny; Yu. E. Lozovik
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We consider an atom interacting with a quantized electromagnetic field inside a cavity with variable parameters. The atom in the ground state located in the initially empty cavity can be excited by variation of cavity parameters. We have discovered two mechanisms of atomic excitation. The first arises due to the interaction of the atom with the non-stationary electromagnetic field created by modulation of cavity parameters. If the characteristic time of variation of cavity parameters is of the...
Source: http://arxiv.org/abs/quant-ph/0008066v2
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Sep 18, 2013
09/13
by
Marieke Postma
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The temperature of the cosmic microwave background increases with redshift; at sufficiently high redshift it becomes possible for ultrahigh-energy photons and electrons to produce muons and pions through interactions with background photons. At the same time, energy losses due to interactions with radio background and intergalactic magnetic fields are negligible. The energetic muons and pions decay, yielding a flux of ``signature'' neutrinos with energies $E_\nu \sim 10^{17}$eV. Detection of...
Source: http://arxiv.org/abs/astro-ph/0012279v1
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Sep 18, 2013
09/13
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E. Conejero Jarque; F. Cornolti; A. Macchi; H. Ruhl
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We investigate numerically effects related to ``single-cycle'' ionization of dense matter by an ultra-short laser pulse. The strongly non-adiabatic response of electrons leads to generation of a megagauss steady magnetic field in laser-solid interaction. By using two-beam interference, it is possible to create periodic density structures able to trap light and to generate relativistic ionization fronts
Source: http://arxiv.org/abs/physics/0002017v1
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Sep 22, 2013
09/13
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B. M. Roehner; D. Sornette
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Establishing unambiguously the existence of speculative bubbles is an on-going controversy complicated by the need of defining a model of fundamental prices. Here, we present a novel empirical method which bypasses all the difficulties of the previous approaches by monitoring external indicators of an anomalously growing interest in the public at times of bubbles. From the definition of a bubble as a self-fulfilling reinforcing price change, we identify indicators of a possible self-reinforcing...
Source: http://arxiv.org/abs/cond-mat/0001353v1
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Sep 17, 2013
09/13
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N. V. Antonov
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A brief review is given of recent results devoted to the effects of large-scale anisotropy on the inertial-range statistics of the passive scalar quantity $\theta(t,{\bf x})$, advected by the synthetic turbulent velocity field with the covariance $\propto\delta(t-t')|{\bf x}-{\bf x'}|^{\eps}$. Inertial-range anomalous scaling behavior is established, and explicit asymptotic expressions for the structure functions $ S_n (\r) \equiv < [\theta(t,{\bf x}+\r)-\theta(t,{\bf x})]^{n}>$ are...
Source: http://arxiv.org/abs/nlin/0007015v1
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Sep 18, 2013
09/13
by
Tomislav Ivezic
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Different approaches to special relativity (SR) are discussed. The first approach is an invariant approach in which physical quantities in the four-dimensional spacetime are represented by true tensors or equivalently by coordinate-based geometric quantities comprising both components and a basis. This approach we call the ''true transformations (TT) relativity.'' It is compared with the usual covariant approach, which mainly deals with the basis components of true tensors. The third approach...
Source: http://arxiv.org/abs/physics/0012048v1
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Sep 22, 2013
09/13
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Toshiki Shimbori; Tsunehiro Kobayashi
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The present paper deals with some kind of quantum ``velocity'' which is introduced by the method of hydrodynamical analogy. It is found that this ``velocity'' is in general irrotational, namely, a vorticity vanishes, and then a velocity potential must exist in quantum mechanics. In some elementary examples of stable systems we will see what the ``velocities'' are. In particular, the two-dimensional flows of these examples can be expressed by complex velocity potentials whose real and imaginary...
Source: http://arxiv.org/abs/quant-ph/0004086v1
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Sep 22, 2013
09/13
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S. Antoci; L. Mihich
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eye 61
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Some authors have raised the question whether the probabilities stemming from a quantum mechanical computation are entitled to enter the Bell and the Clauser-Horne inequalities. They have remarked that if the quantum probabilities are given the status of conditional ones and the statistics for the various settings of the detectors in a given experiment is properly kept into account, the inequalities happen to be no longer violated. In the present paper a classical simile modeled after the...
Source: http://arxiv.org/abs/quant-ph/0004037v1
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Sep 22, 2013
09/13
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Pierre-Gilles de Gennes
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If we pull out rapidly a metallic frame out of a surfactant solution, we arrive at a "young" soap film with relatively simple features, as noticed first by Lucassen. The weight of the film is equilibrated by a vertical gradient of surface tension. At each level, the local solution concentration equilibrates with the local monolayers. A detailed analysis of the young films was started by us in 1987. We present here an approach which is more illuminating a) the concentration profiles...
Source: http://arxiv.org/abs/cond-mat/0011085v1
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Sep 18, 2013
09/13
by
Shu-dong Zhang
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The temporal fluctuation of the average slope of a ricepile model is investigated. It is found that the power spectrum $S(f)$ scales as $1/f^{\alpha}$ with $\alpha\approx 1.3$ when grains of rice are added only to one end of the pile. If grains are randomly added to the pile, the power spectrum exhibits $1/f^2$ behaviour. The profile fluctuations of the pile under different driving mechanisms are also discussed.
Source: http://arxiv.org/abs/cond-mat/0002270v2
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Sep 19, 2013
09/13
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Jörn Davidsen; Heinz Georg Schuster
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Using the well-known Olami-Feder-Christensen model as our paradigm, we show how to modify uniform driven self-organized critical models to generate $1/f^\alpha$ noise. Our model can reproduce all the main features of $1/f^\alpha$ noise: (1) $\alpha$ is close to one and does not depend on the dimension of the system. (2) The $1/f^\alpha$ behavior is found for very low frequencies. (3) The spatial correlations do not obey a power law. That proves that spatially extended systems based on...
Source: http://arxiv.org/abs/cond-mat/0010158v1
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Sep 18, 2013
09/13
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Jong-Phil Lee; Chun Liu; H. S. Song
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The mass spectrum of the L=1 orbitally excited heavy baryons with light quarks in the spin-flavor symmetric representation is studied by the $1/N_c$ expansion method in the framework of the heavy quark effective theory. The mixing effect from the baryons in the mixed representation is considered. The general pattern of the spectrum is predicted which will be verified by the experiments in the near future. The $1/m_Q$ and SU(3) corrections are also considered. Mass relations for the baryons...
Source: http://arxiv.org/abs/hep-ph/0006267v2
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Jul 20, 2013
07/13
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T. N. Pham
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The large branching ratios for $B \to K\pi$ decays as observed by the CLEO Collaboration indicate that penguin interactions contribute a major part to the decay rates and provide an interference between the Cabibbo-suppressed tree and penguin contributions resulting in a CP-asymmetry between the $B \to K\pi$ and its charge conjugate mode. The CP-averaged decay rates depend also on the weak phase $\gamma$ and give us a determination of this phase. In this talk, I would like to report on a recent...
Source: http://arxiv.org/abs/hep-ph/0009142v1
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Sep 18, 2013
09/13
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Chao-Shang Huang; Shou Hua Zhu
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The differential branching ratio, CP asymmetry and lepton polarization $P_N$ for $B\to ^M X_s\tau^+\tau^-$ in a CP spotaneously broken two Higgs doublet model are compute d. ^M It is shown that contributions of neutral Higgs bosons to the decay are ^M quite significant when $\tan\beta$ is large and $P_N$ can reach five persent.
Source: http://arxiv.org/abs/hep-ph/0002018v3
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Sep 18, 2013
09/13
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Taizo Muta; Akio Sugamoto; Mao-Zhi Yang; Ya-Dong Yang
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Motivated by recent measurements, we investigate $B\to \pi \pi, K \pi$ decay modes in the framework of QCD improved factorization, which was recently proposed by Beneke $et al$. We find that all the measured branching ratios are well accommodated in the reasonable parameter space except for $B\to K^0 \pi^0 $. We also discuss in detail the strong penguin contributions and the ${\cal O}(\alpha_s)$ corrections to the chirally enhanced terms. We find that the weak phase $\gamma$ lies in the region...
Source: http://arxiv.org/abs/hep-ph/0006022v2
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Sep 18, 2013
09/13
by
Xiao-Gang He; J. P. Ma; Chung-Yi Wu
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We study $B\to \phi K$ and $B\to \phi X_s$ decays in the heavy quark limit using perturbative QCD. The next leading order corrections introduce substantial modifications to the naive factorization results (more than 50%). The branching ratio $Br(B\to \phi K)$ is predicted to be in the range $(F^{B\to K}_1(m^2_\phi)/0.33)^2(3.5\sim 4.2) \times 10^{-6}$ which is within the one $\sigma$ allowed region from the central value of $6.2\times 10^{-6}$ measured by CLEO, but outside the one $\sigma$...
Source: http://arxiv.org/abs/hep-ph/0008159v2
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Sep 18, 2013
09/13
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P. H. Chankowski; L. Slawianowska
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We present the results of the complete one-loop computation of the $B^0_{d,s}\to l^+l^-$ decay rate in the MSSM. Both sources of the FCNC, the CKM matrix and off-diagonal entries of the sfermion mass matrices are considered. Strong enhancement of the branching ratio (compared to the SM prediction) can be obtained in the large $\tan\beta\sim m_t/m_b$ regime in which the neutral Higgs boson ``penguin'' diagrams dominate. We make explicit the strong dependence of this enhancement on the top...
Source: http://arxiv.org/abs/hep-ph/0008046v1
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Sep 22, 2013
09/13
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Cheng-Ju Stephen Lin
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We set a preliminary 95% C.L. exclusion on the oscillation frequency of $B_s^0 - \bar{B_s^0}$ mixing using a sample of 400,000 hadronic $Z^0$ decays collected by the SLD experiment at the SLC during the 1996-98 run. Three analyses are presented in this paper. The first analysis partially reconstructs the $B_s^0$ by combining a fully reconstructed $D_s$ with the remaining charged B decay tracks. The second analysis selects a sample of events with a partially reconstructed charm vertex and a...
Source: http://arxiv.org/abs/hep-ex/0011040v1
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Sep 22, 2013
09/13
by
C. Quesne; N. Vansteenkiste
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$C_{\lambda}$-extended oscillator algebras generalizing the Calogero-Vasiliev algebra, where $C_{\lambda}$ is the cyclic group of order $\lambda$, are studied both from mathematical and applied viewpoints. Casimir operators of the algebras are obtained, and used to provide a complete classification of their unitary irreducible representations under the assumption that the number operator spectrum is nondegenerate. Deformed algebras admitting Casimir operators analogous to those of their...
Source: http://arxiv.org/abs/math-ph/0003025v1
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Sep 18, 2013
09/13
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F. S. Navarra; M. Nielsen; M. E. Bracco; M. Chiapparini; C. L. Schat
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The $H^*H\pi$ form factor for H = B and D mesons is evaluated in a QCD sum rule calculation. We study the Borel sum rule for the three point function of two pseudoscalar and one vector meson currents up to order four in the operator product expansion. The double Borel transform is performed with respect to the heavy meson momenta. We discuss the momentum dependence of the form factors and two different approaches to extract the $H^*H\pi$ coupling constant.
Source: http://arxiv.org/abs/hep-ph/0005026v3
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Sep 18, 2013
09/13
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P. Banerjee; R. Shyam
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We investigate the effects arising out of the $E1 - E2$ interference in the Coulomb dissociation of $^8$B at beam energies below and around 50 MeV/nucleon. The theory has been formulated within a first order semiclassical scheme of Coulomb excitation, in which both the ground state and the continuum state wave functions of $^8$B enter as inputs. We find that the magnitude of the interference could be large in some cases. However, there are some specific observables which are free from the...
Source: http://arxiv.org/abs/nucl-th/0008025v2
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Sep 19, 2013
09/13
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Robert D. Mawhinney
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We are using domain wall fermions to study $K \to \pi \pi$ matrix elements by measuring $K \to \pi$ and $K \to 0$ matrix elements on the lattice and employing chiral perturbation theory to relate these to the desired physical result. The residual chiral symmetry breaking of domain wall fermions with a finite extent in the fifth dimension impacts these measurements. Using the Ward-Takahashi identities, we investigate residual chiral symmetry breaking effects for divergent quantities and study...
Source: http://arxiv.org/abs/hep-lat/0010030v2
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Sep 22, 2013
09/13
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T. Blum
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We present a lattice calculation of the $K\to\pi$ and $K\to 0$ matrix elements of the $\Delta S=1$ effective weak Hamiltonian which can be used to determine $\epsilon^\prime/\epsilon$ and the $\Delta I=1/2$ rule for $K$ decays in the Standard Model. The matrix elements for $K\to\pi\pi$ decays are related to $K\to\pi$ and $K\to 0$ using lowest order chiral perturbation theory. We also present results for the kaon $B$ parameter, $B_K$. Our quenched domain wall fermion simulation was done at...
Source: http://arxiv.org/abs/hep-lat/0011042v1
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Sep 18, 2013
09/13
by
Mu-Lin Yan
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Electromagnetic masses of neutral $K^*(892)$ may be larger than one of charged $K^*(892)$. It is unusual and is called $K^*$-EM-mass anomaly. We review the studies on this issue, and point out that $K^*$-mass splitting can be measured in BES accurately.
Source: http://arxiv.org/abs/hep-ph/0012105v1
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Sep 22, 2013
09/13
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C. Q. Geng; C. C. Lih; C. C. Liu
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We study the CP conserving and violating contributions to the decay of $\knng$ in the standard model. In our analysis, we use the form factors for $K\to\gamma$ transitions calculated directly in the entire physical range of momentum transfer within the light front model. We find that the branching ratios for the CP conserving and violating parts are about $1.0\times 10^{-13}$ and $1.5\times 10^{-15}$, respectively.
Source: http://arxiv.org/abs/hep-ph/0004164v1
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Sep 22, 2013
09/13
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G. Amoros; J. Bijnens; P. Talavera
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The $F$ and $G$ form-factors of $K_{\ell4}$ and the quark condensates are calculated to ${\cal O}(p^6)$ in Chiral Perturbation Theory (CHPT). Full formulas are presented as much as possible. A full refit of most of the ${\cal O}(p^4)$ CHPT parameters is done with a discussion of all inputs and underlying assumptions. We discuss the consequences for the vacuum expectation values, decay constants, pseudoscalar masses and $\pi$-$\pi$ scattering.
Source: http://arxiv.org/abs/hep-ph/0003258v1
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Sep 22, 2013
09/13
by
Gabriel Amoros; Johan Bijnens; Pere Talavera
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We present the results from our two-loop calculations of masses, decay-constants, vacuum-expectation-values and the $K_{\ell4}$ form-factors in three-flavour Chiral Perturbation Theory (CHPT). We use this to fit the $L_i^r$ to two-loops and discuss the ensuing predictions for $\pi\pi$-threshold parameters.
Source: http://arxiv.org/abs/hep-ph/0011023v1
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Jul 20, 2013
07/13
by
Mathieu Dutour
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We extend a classical result by Rankin. We consider the following question: given $n$ vectors $v_i$ in the ball of radius $R$ of an infinite dimensional Banach space ${\cal B}$ with $d(v_i,v_j)\geq 1$, can we bound the number $n$?
Source: http://arxiv.org/abs/math/0009142v2
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Sep 19, 2013
09/13
by
N. J. Kalton; G. Lancien
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We investigate the problem of $L^p$-maximal regularity on Banach spaces having a Schauder basis. Our results improve those of a recent paper.
Source: http://arxiv.org/abs/math/0010156v1
