February 1998 arXiv papers — page 3

Ferruccio Feruglio

We analyse in detail the behaviour of supersymmetric QCD with a number of flavours M smaller than the number of colours N, for quark masses smaller than the dynamically generated scale. In this regime, we find it useful to move from meson superfields to Nambu-Goldstone-like variables. In particular we work out the mass spectrum and the set of decay constants

V. D. Efros, J. M. Bang

It is found here that the 1/2+ first excited state of 9Be is a virtual state with the energy of -23.5 KeV. The line shape for the excitation of the state is approximated with a simple analytic form based on the effective range expansion. The partner in 9B of this state is found to be a resonance with a maximum in the peak at about 1.1 MeV, FWHM of 1.5 MeV, a

T. Tamura, Y Fukazawa, H. Kaneda, K. Makishima

The results obtained from the ASCA observations of the cluster of galaxies Abell 3627 are presented. This cluster, located behind the Milky way, was recently found to be a nearby, X-ray bright and very rich cluster. Pointed observations onto the central region of the cluster gave a gas temperature of $\sim7$ keV and a metallicity of about 0.2 solar. An offse

S. B. Dubovichenko

Processes of direct cluster photodisintegration of 4He nucleus into p3H and n3He channels are considered on the base of two-cluster potential models. Intercluster interactions being in agreement with elastic scattering phase shifts and characteristics of the bound state of a nucleus have, in some cases, forbidden states. The scattering phase shifts and poten

J. A. Minahan, D. Nemeschansky, C. Vafa, N. P. Warner

We study certain properties of six-dimensional tensionless E-strings (arising from zero size $E_8$ instantons). In particular we show that $n$ E-strings form a bound string which carries an $E_8$ level $n$ current algebra as well as a left-over conformal system with $c=12n-4-{248n \over n+30}$, whose characters can be computed. Moreover we show that the char

Vlatko Vedral, Martin B. Plenio

Quantum computers require quantum logic, something fundamentally different to classical Boolean logic. This difference leads to a greater efficiency of quantum computation over its classical counter-part. In this review we explain the basic principles of quantum computation, including the construction of basic gates, and networks. We illustrate the power of

Juergen Audretsch, Vladimir Skarzhinsky

We investigate the scattering of neutral polarizable atoms from an electrically charged wire placed in a homogeneous magnetic field. The atoms carry an induced electric dipole. The reflecting wire is discussed. We calculate the scattering amplitude and cross section the practically more important case that atoms are totally absorbed at the surface of the wir

N. E. Mavromatos, D. V. Nanopoulos

We focus on potential mechanisms for `energy-loss-free' transport along the cell microtubules, which could be considered as realizations of Fröhlich's ideas on the role of solitons for superconductivity and/or biological matter. In particular, by representing the MT arrangements as `cavities',we present a novel scenario on the formation of macros

W. G. Unruh

The radiation reaction fields are calculated for an accelerated changing dipole in scalar and electromagnetic radiation fields. The acceleration reaction is shown to alter the damping of a time varying dipole in the EM case, but not the scalar case. In the EM case, the dipole radiation reaction field can exert a force on an accelerated monopole charge associ

Pavol Severa

We present a picture of Lagrangean mechanics, free of some unnatural features (such as complete divergences). As a byproduct, a completely natural U(1)-bundle over the phase space appears. The correspondence between classical and quantum mechanics is very clear, e.g. no topological ambiguities remain. Contact geometry is the basic tool.

John R. de Bruyn, C. Bizon, M. D. Shattuck, D. Goldman

The stability of convection rolls in a fluid heated from below is limited by secondary instabilities, including the skew-varicose and crossroll instabilities. We observe a stability boundary defined by the same instabilities in stripe patterns in a vertically oscillated granular layer. Molecular dynamics simulations show that the mechanism of the skew-varico

G. Jonkmans, I. S. Towner, B. Sur

The sensitivity of the Sudbury Neutrino Observatory (SNO) to measure the shape of the recoil electron spectrum in the charged-current reaction of $^{8}$B solar neutrinos interacting with deuterium can be improved if the results of a $^{8}$Li beta-decay calibration experiment are included in the test. We calculate an improvement in sensitivity, under certain

V. B. Belyaev, D. V. Naumov, F. M. Penkov

We estimate the nuclear fusion rates for the transition OH-->F from the ground and excited molecular states and also consider effect of screening of electric charges of nuclei by bound electrons in the case of colliding atoms O and H. We show that the fusion rate for the molecular state is vanishingly small while the electron screening drastically changes th

A. G. Percus, O. C. Martin

Take N sites distributed randomly and uniformly on a smooth closed surface. We express the expected distance <D_k(N)> from an arbitrary point on the surface to its kth-nearest neighboring site, in terms of the function A(l) giving the area of a disc of radius l about that point. We then find two universalities. First, for a flat surface, where A(l)=πl^2, the

H. Albuquerque, S. Majid

We show that the octonions are a twisting of the group algebra of Z_2 x Z_2 x Z_2 in the quasitensor category of representations of a quasi-Hopf algebra associated to a group 3-cocycle. We consider general quasi-associative algebras of this type and some general constructions for them, including quasi-linear algebra and representation theory, and an automorp

J. -P. Dufour, M. Zhitomirskii

We give a normal form for families of 3-dimensional Poisson structures. This allows us to classify singularities with nonzero 1-jet and typical bifurcations. The Appendix contains corollaries on classification of families of integrable 1-forms on $R^3

Jacek Pawełczyk

We introduce a $N_c\times N_c$ matrix model with $\mathcal{N}=2$ supersymmetries and show its relation to the topological rigid string and the topological YM$_2$. This allows to connect the latter two theories directly. Moreover the construction leads to a new insight in the \ninfty limit. Finally a quantum mechanical matrix theory is proposed which may desc

J. Naud, I. Nemenman, M. Van Raamsdonk, V. Periwal

The usual proof of renormalizability using the Callan-Symanzik equation makes explicit use of normalization conditions. It is shown that demanding that the renormalization group functions take the form required for minimal subtraction allows one to prove renormalizability using the Callan-Symanzik equation, without imposing normalization conditions. Scalar f

Daniel Zwanziger

We review the Coulomb gauge in QCD and report some recent results. The minimal Coulomb gauge is defined and the fundamental modular region, a region without Gribov copies, is described. The Coulomb gauge action is expressed in terms of the dynamical degrees of freedom with an instantaneous Coulomb interaction, and its physical meaning is discussed. The local

Theodora Ioannidou, Wojtek Zakrzewski

We present a Lagrangian formulation for the general modified chiral model. We use it to discuss the Hamiltonian formalism for this model and to derive the commutation relations for the chiral field. We look at some explicit examples and show that the Hamiltonian, containing a contribution involving a Wess-Zumino term, is conserved, as required.

George Chapline

The author has previously suggested that the ground state for 4-dimensional quantum gravity can be represented as a condensation of non-linear gravitons connected by Dirac strings. In this note we suggest that the low-lying excitations of this state can be described by a quasi-topological action corresponding to a trilinear coupling of solitonic 8-branes and

O. J. P. Eboli, E. M. Gregores, F. Halzen

The measurement of the inelastic photoproduction of charmonium at HERA seems to have ignited a new charmonium crisis. The (already discredited) color singlet model fits the data for large charmonium energy fraction z, where the NRQCD model qualitatively fails. We here point out that by the straightforward inclusion of color singlet and octet processes in the

J Bordes, HM Chan, J. Pfaudler, ST Tsou

A method developed from the Dualized Standard Model for calculating the quark CKM matrix and masses is applied to the parallel problem in neutrino oscillations. Taking the parameters determined from quarks and the masses of two neutrinos: $m_3^2 \sim 10^{-2} - 10^{-3} eV^2$ suggested by atmospheric neutrino data, and $m_2^2 \sim 10^{-10} eV^2$ suggested by t

Aneesh V. Manohar

1. Introduction 2. The Gross-Neveu Model 3. QCD 3.1 N-Counting Rules for Diagrams 3.1.1 U(1) Ghosts 3.2 The &#39;t Hooft Model 3.3 $N$-Counting Rules for Correlation Functions 3.4 The Master Field 4. Meson Phenomenology 4.1 Zweig&#39;s Rule 4.2 Exotics 4.3 Chiral Perturbation Theory 4.4 Non-leptonic K Decay 4.5 $K-\bar K$ mixing 4.6 Axial U(1) and the eta&#3

Kenzo Ogure, Joe Sato

Using auxiliary-mass method, O(N) invariant scalar model is investigated at finite temperature. This mass and an evolution equation allow us to calculate an effective potential without an infrared divergence. Second order phase transition is indicated by the effective potential. The critical exponents are determined numerically.

Haim Goldberg

The electromagnetic two-body interaction energy is modified in the thermal environment of the solar core. The modifications are shown to imply a gross violation of standard solar physics unless the dispersion relation ω_t(k) for the transverse modes of the photon is altered to include a transverse mass. A non-zero transverse mass $m_t^2\simeq e^2 n_e/m_e$ is

V. I. Zakharov

In two lectures, we overview the renormalon and renormalon-related techniques and their phenomenological applications. We begin with a single renormalon chain which is a well defined and systematic way to specify the character of corrections in inverse powers of the total energy to observables directly in Minkowski space. Renormalons demonstrate also presenc

Hung-Liang Lai, Hsiang-nan Li

We show that the Sudakov factor from the resummation of double logarithms $\ln(s/k_T^2)$ contained in the distribution functions is responsible for the $k_T$ smearing mechanism employed in the next-to-leading-order QCD ($αα_s^2$) calculations of direct photon production. $s$ is the center-of-mass energy, and $k_T$ the transverse momentum carried by a parton

J. Hosek

Formation of a vacuum like domain of the strong-interaction chiral condensate misaligned with respect to the electroweak symmetry breaking arguably modifies the mass spectrum of electroweak gauge bosons and their interactions in that domain in an observable manner. In particular,photon acquires the mass $m_γ\sim{1/2}f_π\sin2θ_{W}$.

A. Khodjamirian, R. Rückl, C. W. Winhart

QCD sum rules on the light-cone are derived for the sum $f^+ + f^-$ of the $B\to π$ and $D\to π$ form factors taking into account contributions up to twist four. Combining the results with the corresponding $f^+$ form factors calculated previously by the same method, we obtain the scalar form factors $f^0$. Our sum rule predictions are compared with lattice

L. Chkhaidze, T. Djobava, G. Gogiberidze, L. Kharkhelauri

The transverse momentum technique is used to analyse charged-particle exclusive data in the central C-Ne and C-Cu interactions at a momentum of 4.5 Gev/c per nucleon.The results are presented in terms of the mean transverse momentum per nucleon projected onto the estimated reaction plane <P_{x}(Y)> as a function of the rapidity Y in the laboratory system. Th

Wilfred H. Tang, Konstantin S. Kostov, Karl F. Freed

We extend to nonequilibrium processes our recent theory for the long time dynamics of flexible chain molecules. While the previous theory describes the equilibrium motions for any bond or interatomic separation in (bio)polymers by time correlation functions, the present extension of the theory enables the prediction of the nonequilibrium relaxation that occu

Igor F. Lyuksyutov, Valery Pokrovsky

We consider a superconducting film with Magnetic Dots Array (MDA) placed on it. Magnetic moments of these dots are supposed to be normal to the film and strong enough to create vortices in the superconducting film. Magnetic interaction between dots is negligible. Below the superconducting transition temperature of the film in zero magnetic field the MDA with

Zheng Weihong

The multi-layer $S={1\over 2}$ square lattice Heisenberg antiferromagnet with up to 6 layers is studied via various series expansions. For the systems with an odd number of coupled planes, the ground-state energy, staggered magnetization, and triplet excitation spectra are calculated via two different Ising expansions. The systems are found to have long rang

C. Kuebert, P. J. Hirschfeld

We consider the problem of the vortex contribution to thermal properties of dirty d-wave superconductors. In the clean limit, Volovik has argued that the main contribution to the density of states in a d-wave superconductor arises from extended quasiparticle states which may be treated semiclassically, giving rise to a specific heat contribution δC(H)\ltsim

H. G. Ballesteros, L. A. Fernandez, V. Martin-Mayor, A. Munoz Sudupe

We study the phase diagram of the site-diluted Ising model in a wide dilution range, through Monte Carlo simulations and Finite-Size Scaling techniques. Our results for the critical exponents and universal cumulants turn out to be dilution-independent, but only after a proper infinite volume extrapolation, taking into account the leading corrections-to-scali

Taeseung Choi, Chang-Mo Ryu, Chul Koo Kim

We consider the external magnetic field effects on the two types of anyon with fractional statistical parameters $p/q$ with coprimes $p$ and $q$, one with fractional charge $e/q $ and flux $p ϕ_0(=hc/e)$(type I), the other with fractional flux $p ϕ_0/q$ and fundamental charge $e$(type II). These two-types of anyons show different behaviors in the presence of

R. Prozorov, E. B. Sonin, E. Sheriff, A. Shaulov

We calculate the distribution of the current density $j$ in superconducting films along the direction of an external field applied perpendicular to the film plane. Our analysis reveals that in the presence of bulk pinning $j$ is inhomogeneous on a length scale of order the inter vortex distance. This inhomogeneity is significantly enhanced in the presence of

Cecilia Clementi, Amos Maritan, Jayanth R. Banavar

We present the results of a self-consistent, unified molecular dynamics study of simple model heteropolymers in the continuum with emphasis on folding, sequence design and the determination of the interaction parameters of the effective potential between the amino acids from the knowledge of the native states of the designed sequences.

Gunter M. Schütz

We show that the stochastic dynamics of a large class of one-dimensional interacting particle systems may be presented by integrable quantum spin Hamiltonians. Generalizing earlier work \cite{Stin95a,Stin95b} we present an alternative description of these processes in terms of a time-dependent operator algebra with quadratic relations. These relations genera

Wellington Cruz

We extract the Braid group structure of a recently derived hierarchy scheme for the filling factors proposed by us which related the Hausdorff dimension, $h$, to statistics, $ν$, of the collective excitations in the context of the Fractional Quantum Hall Effect (FQHE).

Wellington Cruz

We propose a new hierarchy scheme for the filling factor, a parameter which characterizes the occurrence of the Fractional Quantum Hall Effect (FQHE). We consider the Hausdorff dimension, $h$, as a parameter for classifying fractional spin particles, such that, it is written in terms of the statistics of the collective excitations. The number $h$ classifies

Juan M. Lopez, Jean Schmittbuhl

We argue that fracture surfaces may exhibit anomalous dynamic scaling properties akin to what occurs in some models of kinetic roughening. We determine the complete scaling behavior of the local fluctuations of a brittle fracture in a granite block from experimental data. We obtain a global roughness exponent $χ= 1.2$ which differs from the local one, $χ_{lo

N. Schopohl, O. V. Dolgov

We present a thermodynamics argument against a strictly linear temperature dependence of the magnetic penetration depth, which applies to superconductors with arbitrary pairing symmetry at low temperatures.

H. Kunz, B. Shapiro

We consider the Rosenzweig-Porter model of random matrix which interpolates between Poisson and gaussian unitary statistics and compute exactly the two-point correlation function. Asymptotic formulas for this function are given near the Poisson and gaussian limit.

K. Varga

We re-examine the results of A. Thilagam [Phys. Rev. B 55, 7804 (1997)], who calculated the ratio of the binding energies of the two dimensional exciton complexes. We point out that, for charged biexciton complexes, this calculation is oversimplified, and these systems do not always form bound states if they interact via pure Coulomb interaction. If experime

K. Varga, J. Usukura, Y. Suzuki

A new, hitherto unknown bound state of the positronium molecule, with orbital angular momentum L=1 and negative parity is reported. This state is stable against autodissociation even if the masses of the positive and negative charges are not equal. The existence of a similar state in two-dimension has also been investigated. The fact that the biexcitons have

Juhao Wu, A. Widom

In experiments involving Bose condensed atoms trapped in magnetic bottles, plugging the hole in the bottle potential with a LASER beam produces a new potential with two minima, and thus a condensate order parameter (i.e. wave function) with two maxima. When the trapping potential is removed and the condensate explodes away from the trap, the two wave functio

Bumsoo Kyung

We present the doping dependence of the spectral functions, density of states and low frequency behavior of the self-energy for the 2D Hubbard model on the basis of our recently developed theory for the Hubbard model. Strong 2D critical spin fluctuations dominating near half-filling are completely destroyed by 13 and 20 percent doping concentrations for U=4

Yan V. Fyodorov, Boris Khoruzhenko, H. -J. Sommers

This paper is a detailed account of the recent progress in understanding the statistical properties of complex eigenvalues of random non-Hermitian matrices reported earlier in our two short communications: Physics Letters A v.226, 46 (1997) and Phys. Rev. Lett., v.79, 557 (1997)

Pavel Cejnar, Jan Jolie

The degree of chaos in the Interacting Boson Model (IBM-1) is compared with what we call the &#34;dynamical-symmetry content&#34; of the system. The latter is represented by the information entropy of the eigenfunctions with respect to bases associated with dynamical symmetries of the IBM-1, and expresses thus the localization of actual eigenfunctions in the

C. Chandre, M. Govin, H. R. Jauslin, H. Koch

In this article, we describe a new renormalization-group scheme for analyzing the breakup of invariant tori for Hamiltonian systems with two degrees of freedom. The transformation, which acts on Hamiltonians that are quadratic in the action variables, combines a rescaling of phase space and a partial elimination of irrelevant (non-resonant) frequencies. It i

C. Chandre, M. Govin, H. R. Jauslin

We analyze the breakup of invariant tori in Hamiltonian systems with two degrees of freedom using a combination of KAM theory and renormalization-group techniques. We consider a class of Hamiltonians quadratic in the action variables that is invariant under the chosen KAM transformations, following the approach of Thirring. The numerical implementation of th

M. Govin, C. Chandre, H. R. Jauslin

We study the stability and breakup of invariant tori in Hamiltonian flows using a combination of Kolmogorov-Arnold-Moser (KAM) theory and renormalization-group techniques. We implement the scheme numerically for a family of Hamiltonians quadratic in the actions to analyze the strong coupling regime. We show that the KAM iteration converges up to the critical

Antony A. Stark, John E. Carlstrom, Frank P. Israel, Karl M. Menten

A 10 meter diameter submillimeter-wave telescope has been proposed for the NSF Amundsen-Scott South Pole Station. Current evidence indicates that the South Pole is the best submillimeter-wave telescope site among all existing or proposed ground-based observatories. Proposed scientific programs place stringent requirements on the optical quality of the telesc

Blaise Canzian

Spiral density wave theories demand that grand design spiral structure be bounded, at most, between the inner and outer Lindblad resonances of the spiral pattern. The corotation resonance lies between the outer and inner Lindblad resonances. The locations of the resonances are at radii whose ratios to each other are rather independent of the shape of the rot

Colleen A. Wilson, Mark H. Finger, B. Alan Harmon, Deepto Chakrabarty

GRO J2058+42, a transient 198 second x-ray pulsar, was discovered by the Burst and Transient Source Experiment (BATSE) on the Compton Gamma-Ray Observatory (CGRO), during a &#34;giant&#34; outburst in 1995 September-October. The total flux peaked at about 300 mCrab (20-50 keV) as measured by Earth occultation. The pulse period decreased from 198 s to 196 s d

L. da Costa, E. Bertin, E. Deul, T. Erben

The ESO Imaging Survey (EIS) presented in early issues of the Messenger, and with up-to-date information on the ongoing observations available on the Web (http://www.eso.org/eis), is a concerted effort by ESO and the Member State community to provide targets for the first year of operation of the VLT. It consists of two parts: a relatively wide-angle survey

Robert Popham, Charles F. Gammie

In a previous paper we have written down equations describing steady-state, optically thin, advection-dominated accretion onto a Kerr black hole (Gammie and Popham 1997, hereafter Paper I). In this paper we survey the numerical solutions to these equations. We find that the temperature and density of the gas in the inner part of the accretion flow depend str

Mauro Giavalisco, Charles C. Steidel, Kurt L. Adelberger, Mark E. Dickinson

We have measured the angular correlation function w(theta) for a sample of 871 Lyman-break galaxies (LBGs) at z=3. Fitting a power-law to a weighted average of w(theta) from 5 fields, we find the amplitude to be A_w=2 arcsec^β and the slope β=0.9. The slope is the same as in the local and moderate redshift universe. A slope β=0.25 or shallower is ruled out b

S. Andreon, N. Capuano, G. Gargiulo, G. Longo

This paper have been withdraw by the autors, because of a too early submission.

David B. Kaplan, Martin J. Savage, Mark B. Wise

We elaborate on a new technique for computing properties of nucleon-nucleon interactions in terms of an effective field theory derived from low energy NN scattering data. Details of how the expansion is carried out to higher orders are presented. Analytic formulae are given for the amplitude to subleading order in both the 1S0 and 3S1-3D1 channels.

David Garfinkle, G. Comer Duncan

We perform numerical simulations of the gravitational collapse of a spherically symmetric scalar field. For those data that just barely do not form black holes we find the maximum curvature at the position of the central observer. We find a scaling relation between this maximum curvature and distance from the critical solution. The scaling relation is analog

Stephen E. Vance, Tamas Csorgo, Dmitri Kharzeev

The effective intercept parameter of the two-pion Bose-Einstein correlation function, lambda_*, is found to be sensitive to the partial restoration of U_A(1) symmetry in ultra-relativistic nuclear collisions. An increase in the yield of the eta&#39; meson, proposed earlier as a signal of partial U_A(1) restoration, is shown to create a ``hole&#39;&#39; in th

David A. Lowe

The statistical entropy of black holes in M-theory is considered. Assuming Matrix theory is the discretized light-cone quantization of a theory with eleven-dimensional Lorentz invariance, we map the counting problem onto the original Gibbons-Hawking calculation of the thermodynamic entropy.

G. Akemann, P. H. Damgaard

Using relations from random matrix theory, we derive exact expressions for all $n$-point spectral correlation functions of Dirac operator eigenvalues in terms of finite-volume partition functions. This is done for both chiral symplectic and chiral unitary random matrix ensembles, which correspond to $SU(N_c \geq 3)$ gauge theories with $N_f$ fermions in the

U. Bruzzo, G. Sanguinetti

We show that under the hypotheses of Strominger, Yau and Zaslow&#39;s paper, a mirror partner of a K3 surface $X$ with a fibration in special Lagrangian tori can be obtained by rotating the complex structure of $X$ within its hyperkähler family of complex structures. The same hypotheses force the B-field to vanish.

A. V. Belitsky, D. Mueller

We present the method, based on the use of the broken conformal Ward identities, for the calculation of the anomalous dimensions of conformal operators beyond the leading order of perturbation theory. By means of this technique we find the complete set of two-loop corrections to the off-diagonal elements of the anomalous dimension matrix (the diagonal ones a

V. A. Naumov, T. S. Sinegovskaya, S. I. Sinegovsky

The dependence of the semileptonic kaon decay form factors on the 4-momentum transfer to the lepton pair causes certain changes in the differential decay rates and, hence, it should affect the conventional atmospheric neutrino flux and neutrino flavour ratio. As a case in point, we included these rates into the calculation of the atmospheric neutrino flux at

T. Feldmann, P. Kroll, B. Stech

We propose a new eta-eta&#39; mixing scheme where we start from the quark flavor basis and assume that the decay constants in that basis follow the pattern of particle state mixing. On exploiting the divergences of the axial vector currents - which embody the axial vector anomaly - all basic parameters are fixed to first order of flavor symmetry breaking. Th

M. Nikbakht-Tehrani

In the class of (0,2) heterotic compactifications which has been constructed in the framework of gauged linear sigma models the Calabi-Yau varieties X are realized as complete intersections of hypersurfaces in toric varieties IP and the corresponding gauge bundles (or more generally gauge sheaves) E are defined by some short exact sequences. We show that the

P. Baseilhac, P. Grangé, M. Rausch de Traubenberg

Linearization of homogeneous polynomials of degree n and k variables leads to generalized Clifford algebras. Multicomplex numbers are then introduced in analogy to complex numbers with respect to usual Clifford algebra. In turn multicomplex extensions of trigonometric functions are constructed in terms of `compact&#39; and `non-compact&#39; variables. It giv

A. Harindranath, Rajen Kundu

In this work we address several issues associated with orbital angular momentum relevant for leading twist polarized deep inelastic scattering. We present a detailed analysis of the light-front helicity operator (generator of rotations in the transverse plane) in QCD. We explicitly show that, the operator constructed from the manifestly gauge invariant, symm

S. Bertolini, J. O. Eeg, M. Fabbrichesi

The real part of epsilon&#39;/epsilon measures direct CP violation in the decays of the neutral kaons in two pions. It is a fundamental quantity which has justly attracted a great deal of theoretical as well as experimental work. Its determination may answer the question of whether CP violation is present only in the mass matrix of neutral kaons (the superwe

S. B. Dubovichenko, A. V. Dzhazairov-Kakhramanov

The photodisintegration of the 6Li nucleus through the channels 3He3H, 4He2H and the corresponding radiative capture are considered in simple two-cluster models. Potentials with forbidden states which reproduce the phase shifts of elastic scattering up to energies of 20 MeV are was used to describe cluster interactions. It is shown that such the potential cl

K. M. Gheri, C. Saavedra, P. Toermae, J. I. Cirac

We propose a cavity-QED scheme for the controlled generation of sequences of entangled single-photon wavepackets. A photon is created inside a cavity via an active medium, such as an atom, and decays into the continuum of radiation modes outside the cavity(coupled, for example to an optical fiber). Subsequent wavepackets generated in this way behave as indep

C. Jarzynski

Given a thermodynamic process which carries a system from one equilibrium state to another, we construct a quantity whose average, over an ensemble of microscopic realizations of the process, depends only on these end states, even if at intermediate times the system is out of equilibrium. This result: (1) can be used to express the entropy difference between

G. Goeppert, H. Grabert, N. V. Prokof&#39;ev, B. V. Svistunov

Quantum fluctuations of the charge in the single electron box are investigated. The rounding of the Coulomb staircase caused by virtual electron tunneling is determined by perturbation theory up to third order in the tunneling conductance and compared with precise Monte Carlo data computed with a new algorithm. The remarkable agreement for large conductance

James V. Steele, R. J. Furnstahl

Attempts to apply effective field theory (EFT) methods to nonrelativistic nucleon-nucleon (NN) scattering have raised questions about the nature and limitations of an EFT expansion when used nonperturbatively. We discuss the characteristics of a meaningful EFT analysis and compare them with traditional approaches to NN scattering. A key feature of an EFT tre

Yuri B. Suris, Orlando Ragnisco

We develop a systematic procedure of finding integrable &#39;&#39;relativistic&#39;&#39; (regular one-parameter) deformations for integrable lattice systems. Our procedure is based on the integrable time discretizations and consists of three steps. First, for a given system one finds a local discretization living in the same hierarchy. Second, one considers

Alessandro Campa, Andrea Giansanti

The melting curves of short heterogeneous DNA chains in solution are calculated on the basis of statistical thermodynamics and compared to experiments. The computation of the partition function is based on the Peyrard-Bishop hamiltonian, which has already been adopted in the theoretical description of the melting of long DNA chains. In the case of short chai

S. B. Dubovichenko, A. V. Dzhazairov-Kakhramanov

Elastic and inelastic Coulomb form factors of 6Li and 7Li nuclei are considered on the basis of 4He2H and 3He3H cluster models. Potentials containing forbidden states, which describe main characteristics of bound states and phase shifts of elastic scattering at low energies, are used as intercluster potentials. It is obtained a good description of elastic fo

N. Kaiser, S. Gerstendoerfer, W. Weise

We evaluate, within one-loop chiral perturbation theory, the two-pion exchange diagrams with single and double delta-isobar excitation contributing to elastic NN-scattering. We find that virtual $Δ$-excitation processes (in the static limit) produce the correct amount of isoscalar central attraction as needed in the peripheral partial waves with $L\geq 3$. F

Carlos Ortiz

We prove a Model Existence Theorem for a fully infinitary logic for metric structures. This result is based on a generalization of the notions of approximate formulas and approximate truth in normed structures introduced by Henson and studied in different forms by Anderson and Fajardo & Keisler. This theorem extends Henson&#39;s Compactness Theorem for appro

Radu Todor, Ionuţ Chiose

The goal of this paper is to generalize Demailly&#39;s asymptotic holomorphic Morse inequalities to the case of a covering manifold of a compact manifold. We shall obtain estimates which involve Atiyah&#39;s ``normalized dimension&#39;&#39; of the square integrable harmonic spaces. The techniques used are those of Shubin who gave a proof for the usual Morse

Thomas Peternell, Fernando Serrano

We prove that the Albanese map of a smooth projective threefold, whose anticanonical bundle is nef, is a surjective submersion. We also investigate morphisms of threefolds to curves and surfaces whose relative anticanonical bundle are nef.

E. Moreno, C. Nuñez, F. A. Schaposnik

We obtain electrically charged vortex solutions for the Born-Infeld Higgs system with a Chern Simons term. We analyse numerically these solutions, comparing their properties with those of ``normal&#39;&#39; Nielsen-Olesen vortices and also show that no charged vortex solutions exist in Born-Infeld theory when the Chern Simons term is absent.

Bernard S. Kay

Statistical mechanics explains thermodynamics in terms of (quantum) mechanics by equating the entropy of a microstate of a closed system with the logarithm of the number of microstates in the macrostate to which it belongs, but the question `what is a macrostate?&#39; has never been answered except in a vague, subjective, way. However Hawking&#39;s discovery

Christian Wieczerkowski

We consider renormalization groups of transformations composed of a Gaussian convolution and a field dilatation. As an example, we consider perturbations of a single component real Euclidean free field $\phi$ with covariance $(-\bigtriangleup)^{-1+\frac{\epsilon}{2}}$. We show that the renormalization group admits two equivalent formulations called massless

Roberto Soldati, Lorenzo Sorbo

Some new expressions are found, concerning the one-loop effective action of four dimensional massive and massless Dirac fermions in the presence of general uniform electric and magnetic fields, with $\vec E\cdot \vec H\neq 0$ and $\vec E ^2\neq \vec H ^2$. The rate of pair-production is computed and briefly discussed.

A. F. Ranada, J. L. Trueba

We present a topological mechanism of discretization, which gives for the fundamental electric charge a value equal to the square root of the Planck constant times the velocity of light, which is about 3.3 times the electron charge. Its basis is the following recently proved property of the standard linear classical Maxwell equations: they can be obtained by

K. Ezawa, Y. Matsuo, K. Murakami

We discuss the open string ending on D $p$-branes in IKKT framework. First we determine the boundary conditions of Green-Schwarz superstring which are consistent with supersymmetry and $κ$-symmetry. We point out some subtleties arising from taking the Schild gauge and show that in this gauge the system incorporates the limited dimensional D $p$-branes ($p=3,

Vadim V. Varlamov

The neutrino field is considered in the framework of a complex Clifford algebra $\C_3\cong\C_2\oplus\stackrel{\ast}{\C}_2$. The factor-algebras ${}^ε\C_2$ and ${}^ε\stackrel{\ast}{\C}_2$, which are obtained by means of homomorphic mappings $\C_3\to\C_2$ and $\C_3\to\stackrel{\ast}{\C}_2$, are identified with the neutrino and antineutrino fields, respectively

O. J. P. Eboli, M. C. Gonzalez-Garcia, S. M. Lietti, S. F. Novaes

We derive bounds on Higgs and gauge--boson anomalous interactions using the LEP2 data on the production of three photons and photon pairs in association with hadrons. In the framework of $SU(2)_L \otimes U(1)_Y$ effective Lagrangians, we examine all dimension--six operators that lead to anomalous Higgs interactions involving $γ$ and $Z$. The search for Higgs

Marco Aurelio Diaz

We review some of the main features of Bilinear R-Parity Violation (BRpV), defined by a quadratic term in the superpotential which mixes lepton and Higgs superfields and is proportional to a mass parameter epsilon. We show how large values of epsilon can induce a small neutrino mass without fine-tunning. We mention the effect on the mass of the lightest Higg

L. Burakovsky, T. Goldman

We study the origins of the inaccuracies of Schwinger&#39;s nonet mass, and the Sakurai mass-mixing angle, formulae for the pseudoscalar meson nonet, and suggest new versions of them, modified by the inclusion of the pseudoscalar decay constants. We use these new formulae to determine the pseudoscalar decay constants and mixing angle. The results obtained, f

Hiroko Ichie, Hideo Suganuma

Based on the dual Higgs picture for confinement, we study monopole properties in the maximally abelian (MA) gauge using the lattice QCD. The monopole carries a large fluctuation of the gluon field and provides a large abelian action in abelian projected QCD (AP-QCD). We find large cancellation between abelian part and off-diagonal part of the action density

M. I. Antonoyiannakis, J. B. Pendry

We develop a general methodology for numerical computations of electromagnetic (EM) fields and forces in matter, based on solving the macroscopic Maxwell&#39;s equations in real space and adopting the Maxwell Stress Tensor formalism. Our approach can be applied to both dielectric and metallic systems of frequency-dependent dielectric function; as well as to

A. Furusaki, T. Hikihara

The Kondo effect in a one-dimensional spin-1/2 XXZ model in the gapless XY regime (-1<Delta<=1) is studied both analytically and numerically. In our model an impurity spin (S=1/2) is coupled to a single spin in the XXZ spin chain. Perturbative renormalization-group (RG) analysis is performed for various limiting cases to deduce low-energy fixed points. It is

M. Mueller, M. Schick

The self-assembly of monoacyl lipids in solution is studied employing a model in which the lipid&#39;s hydrocarbon tail is described within the Rotational Isomeric State framework and is attached to a simple hydrophilic head. Mean-field theory is employed, and the necessary partition function of a single lipid is obtained via a partial enumeration over a lar