December 2001 arXiv papers — page 5
Showing 401–500 of 2,706 papers
P. J. Cameron, S. Majid
We interpret a recent formula for counting orbits of $GL(d,F_q)$ in terms of counting fixed points as addition in the affine braided line. The theory of such braided groups (or Hopf algebras in braided categories) allows us to obtain the inverse relationship, which turns out to be the same formula but with $q$ and $q^{-1}$ interchanged (a perfect duality bet
Jeffrey Shallit
The well-studied local postage stamp problem (LPSP) is the following: given a positive integer k, a set of postive integers 1 = a1 < a2 < ... < ak and an integer h >= 1, what is the smallest positive integer which cannot be represented as a linear combination x1 a1 + ... + xk ak where x1 + ... + xk <= h and each xi is a non-negative integer? In this note we
Pengfei Guan, Guofang Wang
We study a fully nonlinear flow for conformal metrics. The long-time existence and the sequential convergence of flow are established for locally conformally flat manifolds. As an application, we solve the $\sk$-Yamabe problem for locally conformal flat manifolds when $k \neq n/2$.
On the Hamiltonian and Lagrangian structures of time-dependent reductions of evolutionary PDEs
math.DGMonica Ugaglia
In this paper we study the reductions of evolutionary PDEs on the manifold of the stationary points of time--dependent symmetries. In particular we describe how that the finite dimensional Hamiltonian structure of the reduced system is obtained from the Hamiltonian structure of the initial PDE and we construct the time--dependent Hamiltonian function. We als
Saharon Shelah, Lutz Strüngmann
Let T be an abelian group and lambda an uncountable regular cardinal. We consider the question of whether there is a lambda-universal group G^* among all torsion-free abelian groups G of cardinality less than or equal to lambda satisfying Ext(G,T)=0. Here G^* is said to be lambda-universal for T if, whenever a torsion-free abelian group G of cardinality less
Rüdiger Göbel, Saharon Shelah, Simone Wallutis
In this paper we mainly consider the class LN of all locally nilpotent groups. We first show that there is no universal group in LN_lambda if lambda is a cardinal such that lambda = lambda^{aleph_0}; here we call a group G universal (in LN_lambda) if any group H in LN_lambda can be embedded into G where LN_lambda denotes the class of all locally nilpotent gr
Qiang Ye
In this paper, we first present the complete list of the singularity types of the Picard number one Gorenstein log del Pezzo surface and the number of the isomorphism classes with the given singularity type. Then we give out a method to find out all singularity types of Gorenstein log del Pezzo surface. As an application, we present the complete list of the
Fred Curtis
Existing planar map encodings neglect maps with loops. The presented scheme encodes any connected planar map in 4 bits/edge. Encoding and decoding time is O(edges). Implicit face/edge/vertex orderings and canonical encodings are discussed.
Yassen S. Stanev
Introduction to two dimensional conformal field theory on open and unoriented surfaces. The construction is illustrated in detail on the example of SU(2) WZW models.
Masatoshi Nozaki
We study D-branes in Kazama-Suzuki models by means of the boundary state description. We can identify the boundary states of Kazama-Suzuki models with the solitons in N=2 Landau-Ginzburg theories. We also propose a geometrical interpretation of the boundary states in Kazama-Suzuki models.
Kenzo Ogure, Jiro Arafune, Takufumi Yoshida
We investigate the stability of an Fermi ball(F-ball) within the next-to-leading order approximation in the thin wall expansion. We find out that an F-ball is unstable in case that it is electrically neutral. We then find out that an electrically charged F-ball is metastable in some parameter range. We lastly discuss the allowed region of parameters of an F-
Qun Wang, Krzysztof Redlich, Horst Stöcker, Walter Greiner
We derive the kinetic equation for pure gluon QCD plasma in a general way, applying the background field method. We show that the quantum kinetic equation contains a term as in the classical case, that describes a color charge precession of partons moving in the gauge field. We emphasize that this new term is necessary for the gauge covariance of the resulti
Timothy L. Barklow, Albert De Roeck
The physics at an e+e- linear collider with a center of mass energy of 3-5 TeV is reviewed. The following topics are covered: experimental environment, Higgs physics, supersymmetry, fermion pair-production, WW scattering, extra dimensions, non-commutative theories, and black hole production.
Gerald Eigen, Rick Gaitskell, Graham D. Kribs, Konstantin T. Matchev
This is the summary report of the ``Indirect Investigations of SUSY'' subgroup of the P3 Physics Group at Snowmass 2001.
J. -F. Yang
Through two loop effective potential we demonstrate that the $\bar{MS}$ scheme of dimensional regularization and Jackiw's prescription in cut-off regularization allow for the dynamical breaking solution in massless $λϕ^4$ theory, while the Coleman-Weinberg prescription does not. The beta function of the broken phase is negative, like in the one loop effe
P. Hajicek, I. Kouletsis
The dynamical system constituted by two spherically symmetric thin shells and their own gravitational field is studied. The shells can be distinguished from each other, and they can intersect. At each intersection, they exchange energy on the Dray, 't Hooft and Redmount formula. There are bound states: if the shells intersect, one, or both, external shel
Jiangping Hu, Shou-Cheng Zhang
In this work we investigate collective excitations at the boundary of a recently constructed 4D quantum Hall state. Local bosonic operators for creating these collective excitations can be constructed explicitly. Massless relativistic wave equations with helicity $S$ can be derived exactly for these operators from their Heisenberg equation of motion. For the
Alireza Saffarzadeh
The effect of spin-disorder scattering on perpendicular transport in a magnetic monolayer is considered within the single-site Coherent Potential Approximation (CPA). The exchange interaction between a conduction electron and localized moment of the magnetic ion is treated with the use of the $s-f$ model. Electron-spin polarization is evaluated in the tunnel
S. Biermann, A. Dallmeyer, C. Carbone, W. Eberhardt
We present angle-resolved photoemission spectra of the $γ$-phase of manganese as well as a theoretical analysis using a recently developed approach that combines density functional and dynamical mean field methods (LDA+DMFT). The comparison of experimental data and theoretical predictions allows us to identify effects of the Coulomb correlations, namely the
Paulsamy Muruganandam, Sadhan K. Adhikari
For an attractive trapped Bose-Einstein condensate an imaginary three-body recombination loss term and an imaginary linear source term are usually included in the Gross-Pitaevskii (GP) equation for a proper account of dynamics. Under the action of an impulsive force, generated by suddenly changing the atomic interaction or the trapping potential, the solutio
A. Furusaki, K. A. Matveev
We consider a resonant level coupled to a chiral Luttinger liquid which can be realized, e.g., at a fractional quantum Hall edge. We study the dependence of the occupation probability n of the level on its energy εfor various values of the Luttinger-liquid parameter g. At g<1/2 a weakly coupled level shows a sharp jump in n(ε) at the Fermi level. As the coup
Z. Hadzibabic, C. A. Stan, K. Dieckmann, S. Gupta
We have produced a macroscopic quantum system in which a Li-6 Fermi sea coexists with a large and stable Na-23 Bose-Einstein condensate. This was accomplished using inter-species sympathetic cooling of fermionic Li-6 in a thermal bath of bosonic Na-23.
Comment on "Dynamics in an oil-continuous droplet microemulsion as seen by quasielastic scattering techniques" by T. Hellweg et al
cond-mat.softV. Lisy
It is shown that the interpretation of quasielastic scattering experiments on droplet microemulsions in the paper by T. Hellweg et al., Phys. Chem. Chem. Phys., 2000, 2, 5168, contains serious shortcomings and should be revised.
M. Barbieri, R. G. Gratton
We have reconstructed the galactic orbits of the parent stars of exoplanets. For comparison, we have recalculated the galactic orbits of stars from the Edvardsson et al.(1993) catalog. A comparison between the two samples indicates that stars with planets are not kinematically peculiar. At each perigalactic distance stars with planets have a metallicity syst
M. Girardi, P. Manzato, M. Mezzetti, G. Giuricin
We study the mass-to-light ratio of galaxy systems from poor groups to rich clusters, and present for the first time a large database for useful comparisons with theoretical predictions. We extend a previous work, where B_j band luminosities and optical virial masses were analyzed for a sample of 89 clusters. Here we also consider a sample of 52 more cluster
N. R. Napolitano, M. Arnaboldi, M. Capaccioli
Evidence for a disturbed velocity structure in the outer regions of the galaxy NGC1399 comes from a re-analysis of the planetary nebulae data from Arnaboldi et al. (1994). We find a strong rotation along a P.A.=140 degrees for R<=140'' which is followed by a rapid drop off at larger radii, where the velocity dispersion starts to increase. This kinema
Taichi Kato
We observed an anomalously outbursting state of SU UMa which occurred in 1992. Time-resolved photometry revealed the presence of signals with a period of 0.0832 +/- 0.0019 d, which is 3.6 sigma longer than the orbital period (0.07635 d) of this system. We attributed this signal to superhumps, based on its deviation from the orbital period and its characteris
M. M. Guzzo, P. C. de Holanda, M. Maltoni, H. Nunokawa
We reanalyze the non-standard interaction (NSI) solutions to the solar neutrino problem in the light of the latest solar, atmospheric and reactor neutrino data. We show that such solutions, although preferred by the solar data and consistent with the oscillation description of the atmospheric neutrino data, are ruled out by the first results of the KamLAND r
O. Philipsen
We study a recently proposed gauge invariant, non-local pure gauge observable, which is equivalent to the gluon propagator in a certain gauge. The correlator describes a gluon coupled to static sources and decays with eigenvalues of the Hamiltonian, permitting a non-perturbative definition of a gluonic parton mass. Detailed numerical tests of the observable
Shinji Mukohyama
In brane world scenarios with a bulk scalar field between two branes it is known that 4-dimensional Einstein gravity is restored at low energies on either brane. By using a gauge-invariant gravitational and scalar perturbation formalism we extend the theory of weak gravity in the brane world scenarios to higher energies, or shorter distances. We argue that w
Luc Blanchet
The equations of motion of two point masses have recently been derived at the 3PN approximation of general relativity. From that work we determine the location of the innermost circular orbit or ICO, defined by the minimum of the binary's 3PN energy as a function of the orbital frequency for circular orbits. We find that the post-Newtonian series converg
M. Kostur, J. Luczka, L. Schimansky-Geier
A model of globally coupled phase oscillators under equilibrium (driven by Gaussian white noise) and nonequilibrium (driven by symmetric dichotomic fluctuations) is studied. For the equilibrium system, the mean-field state equation takes a simple form and the stability of its solution is examined in the full space of order parameters. For the nonequilbrium s
Prashanth Jaikumar, Ralf Rapp, Ismail Zahed
We compute the rates of real and virtual photon (dilepton) emission from dense QCD matter in the color-flavor locked (CFL) phase, focusing on results at moderate densities (3-5 times the nuclear saturation density) and temperatures $T\simeq80$ MeV. We pursue two approaches to evaluate the electromagnetic (e.m.) response of the CFL ground state: (i) a direct
Olivier Poujade, Luc Blanchet
Two long-standing problems with the post-Newtonian approximation for isolated slowly-moving systems in general relativity are: (i) the appearance at high post-Newtonian orders of divergent Poisson integrals, casting a doubt on the soundness of the post-Newtonian series; (ii) the domain of validity of the approximation which is limited to the near-zone of the
Celine Boehm, Alain Riazuelo, Steen H. Hansen, Richard Schaeffer
We explore some of the consequences of Dark Matter-photon interactions on structure formation, focusing on the evolution of cosmological perturbations and performing both an analytical and a numerical study. We compute the cosmic microwave background anisotropies and matter power spectrum in this class of models. We find, as the main result, that when Dark M
QCD Corrections to B -> X_{d,s} nu nubar, B_{d,s} -> l^+l^-, K -> pi nu nubar and K_L -> mu^+ mu^- in the MSSM
hep-phC. Bobeth, A. J. Buras, F. Krüger, J. Urban
We compute for the first time QCD corrections to the rare decays B -> X_{d,s} nu nubar, B_{d,s} -> l^+ l^-, K -> pi nu nubar and K_L -> mu^+ mu^-, where l=e or mu, in the context of a supersymmetric extension of the Standard Model (SM) with minimal flavour violation and new operators, in addition to those present in the SM. Assuming that the gluino is heavy,
Angular versus radial correlation effects on momentum distributions of light two-electron ions
physics.chem-phSebastien Ragot, Jean-Michel Gillet, Pierre J. Becker
We investigate different correlation mechanisms for two-electron systems and compare their respective effects on various electron distributions. The simplicity of the wave functions used allows for the derivation of closed-form analytical expressions for all electron distributions. Among other features, it is shown that angular and radial correlation mechani
S. Davidson, S. Forte, P. Gambino, N. Rius
We discuss whether the NuTeV anomaly can be explained, compatibly with all other data, by QCD effects (maybe, if the strange sea is asymmetric, or there is a tiny violation of isospin), new physics in propagators or couplings of the vector bosons (not really), loops of supersymmetric particles (no), dimension six operators (yes, for one specific SU(2)-invari
Scaling Solutions of Inelastic Boltzmann Equations with Over-populated High Energy Tails
cond-mat.stat-mechM. H. Ernst, R. Brito
This paper deals with solutions of the nonlinear Boltzmann equation for spatially uniform freely cooling inelastic Maxwell models for large times and for large velocities, and the nonuniform convergence to these limits. We demonstrate how the velocity distribution approaches in the scaling limit to a similarity solution with a power law tail for general clas
Adsorption in non interconnected pores open at one or at both ends: A reconsideration of the origin of the hysteresis phenomenon
cond-mat.mes-hallB. Coasne, A. Grosman, C. Ortega, M. Simon
We report on an experimental study of adsorption isotherme of nitrogen onto porous silicon with non interconnected pores open at one or at both ends in order to check for the first time the old (1938) but always current idea based on Cohan's description which suggests that the adsorption of gaz should occur reversibly in the first case and irreversibly i
I. Ya. Aref'eva, A. A. Giryavets, P. B. Medvedev
Using algebraic methods the Neveu-Schwarz fermionic matter sliver is constructed. Inspirited by the wedge algebra two equations for the sliver, linear and quadratic, are considered. It is shown that both equations give the same nontrivial answer. The sliver is considered also using CFT methods where it is defined as the limit of the wedge states in the NS se
A. Ali, E. Lunghi, C. Greub, G. Hiller
We update the branching ratios for the inclusive decays $B\to X_s \ell^+ \ell^-$ and the exclusive decays $B\to (K,K^*) \ell^+ \ell^-$, with $\ell=e, \m$, in the standard model by including the explicit $O(\a_s)$ and $Λ_{\hbox{\tiny QCD}} / m_b$ corrections. This framework is used in conjunction with the current measurements of the branching ratios for $B\to
M. Zetenyi, H. W. Barz, Gy. Wolf, B. Kampfer
Within a BUU type transport model we study $ϕ$ meson production in subthreshold Ni+Ni and Ru+Ru reactions. For the first time we included in our model the elementary reaction channels $ρ+N,Δ\to ϕ+N$, $π+N(1520) \to ϕ+N$ and $πρ$ $\to$ $ϕ$. In spite of a substantial increase of the $ϕ$ multiplicities by these channels our results stay significantly below the
R. Mahapatra, CLEO Collaboration
We report the first observation of the exclusive decays \bar B\to D^{(*)}K^{*-}, using 9.66 x 10^{6} B\bar{B} pairs collected at the Υ(4S) with the CLEO detector. We measure the following branching fractions: {\cal B}(B^- -> D^0 K^{*-})=(6.1 +- 1.6 +-1.7)x10^{-4}, {\cal B}(\bar{B^0} -> D^+K^{*-})=(3.7 +- 1.5 +- 1.0) x 10^{-4}, {\cal B}(\bar{B^0} -> D^{*+}K^{
Erik Sjöqvist
It is shown that the molecular Aharonov-Bohm effect is neither nonlocal nor topological in the sense of the standard magnetic Aharonov-Bohm effect. It is further argued that there is a close relationship between the molecular Aharonov-Bohm effect and the Aharonov-Casher effect for an electrically neutral spin$-{1/2}$ particle encircling a line of charge.
Improved variational description of the Wick-Cutkosky model with the most general quadratic trial action
hep-thR. Rosenfelder, A. W. Schreiber
We generalize the worldline variational approach to field theory by introducing a trial action which allows for anisotropic terms to be induced by external 4-momenta of Green's functions. By solving the ensuing variational equations numerically we demonstrate that within the (quenched) scalar Wick-Cutkosky model considerable improvement can be achieved o
G. Vidal, W. Dür, J. I. Cirac
We compute the entanglement cost of several families of bipartite mixed states, including arbitrary mixtures of two Bell states. This is achieved by developing a technique that allows us to ascertain the additivity of the entanglement of formation for any state supported on specific subspaces. As a side result, the proof of the irreversibility in asymptotic
F. Piccinini, A. D. Polosa
In this short note we examine the exclusive three-body B --> Lambdabar p eta' decay using a simple pole model involving a scalar intermediate resonance state. Our aim is to test the recently formulated hypothesis that charmless baryonic B decays could occur mainly in association with eta' or gamma.
FIRST-based survey of Compact Steep Spectrum sources I. MERLIN images of arc-second scale objects
astro-phM. Kunert, A. Marecki, R. E. Spencer, A. J. Kus
Compact Steep Spectrum (CSS) sources are powerful extragalactic radio sources with angular dimensions of the order of a few arcseconds or less. Such a compactness is apparently linked to the youth of these objects. The majority of CSSs investigated so far have been known since the early 1980s. This paper is the first in a series where we report the results o
C. Bagnuls, C. Bervillier
We extent the previous determinations of nonasymptotic critical behavior of Phys. Rev B32, 7209 (1985) and B35, 3585 (1987) to accurate expressions of the complete classical-to-critical crossover (in the 3-d field theory) in terms of the temperature-like scaling field (i.e., along the critical isochore) for : 1) the correlation length, the susceptibility and
N. I. Kochelev, D. -P. Min, V. Vento, A. V. Vinnikov
We calculate the contribution of meson and pomeron exchanges to the double-spin asymmetry in $ρ$-meson electromagnetic production at HERMES energies. We show that the observed double-spin asymmetries, which are large, can be explained by the interference between the natural parity $f_2$-secondary Reggeon and the unnatural parity anomalous $f_1$ exchanges.
Georg Drenkhahn
We study magnetically powered relativistic outflows in which a part of the magnetic energy is dissipated internally by reconnection. For GRB parameters, and assuming that the reconnection speed scales with the Alfven speed, significant dissipation can take place both inside and outside the photosphere of the flow. The process leads to a steady increase of th
K. P. Khemchandani, N. G. Kelkar, B. K. Jain
A detailed study of the effect of the $η$-nucleus final state interaction (FSI) in the $p d \to ^3$He$ η$ reaction close to threshold is presented. The FSI is incorporated through a T-matrix for $η^3$He elastic scattering, constructed using few body equations. This T-matrix accounts for off-shell and binding effects in $η$-nucleus scattering. The energy depe
A study of single sneutrino production in association with fermion pairs at polarised photon colliders
hep-phDilip Kumar Ghosh, Stefano Moretti
We investigate single sneutrino production in the context of R-parity-violating Supersymmetry at future $γγ$ linear colliders. The sneutrino is produced in association with fermion pairs and it is shown that its decays into two further fermions will lead to a clean signal. We also discuss possible backgrounds and the effects of beam polarisation.
Cheuk-Yin Wong
Using a temperature-dependent potential obtained from lattice gauge calculations, we study the stability of heavy quarkonia in the quark-gluon plasma. We find that only the Upsilon(1S) and the eta_b(1S) are bound in the quark-gluon plasma, and have a small binding energy. The quark-gluon plasma may be revealed by an Upsilon(1S) dilepton peak with an invarian
K. Coble, S. Dodelson, M. Dragovan, K. Ganga
We analyze observations of the microwave sky made with the Python experiment in its fifth year of operation at the Amundsen-Scott South Pole Station in Antarctica. After modeling the noise and constructing a map, we extract the cosmic signal from the data. We simultaneously estimate the angular power spectrum in eight bands ranging from large (l ~ 40) to sma
Michael Martin Nieto
The program to construct minimum-uncertainty coherent states for general potentials works transparently with solvable analytic potentials. However, when an analytic potential is not completely solvable, like for a double-well or the linear (gravitational) potential, there can be a conundrum. Motivated by supersymmetry concepts in higher dimensions, we show h
Entangled-Photon Generation from Parametric Down-Conversion in Media with Inhomogeneous Nonlinearity
quant-phGiovanni Di Giuseppe, Mete Atature, Matthew D. Shaw, Alexander V. Sergienko
We develop and experimentally verify a theory of Type-II spontaneous parametric down-conversion (SPDC) in media with inhomogeneous distributions of second-order nonlinearity. As a special case, we explore interference effects from SPDC generated in a cascade of two bulk crystals separated by an air gap. The polarization quantum-interference pattern is found
Andrew Jordan, Mark Srednicki
In a recent paper [Nature 412, 712 (2001)], Zurek has argued that (1) time evolution typically causes chaotic quantum systems to generate structure that varies on the scale of phase-space volume elements of size $(\hbar^2/A)^d$, where A is a classical action characteristic of the state and d is the number of degrees of freedom, and that (2) this structure im
Vlatko Vedral, Elham Kashefi
We apply the axiomatic approach to thermodynamics presented by Giles to derive a unique measure of entanglement for bi-partite pure states. This implies that local manipulations of entanglement in quantum information theory and adiabatic transformations of states in thermodynamics have the same underlying mathematical structure. We discuss possible extension
Jens Siewert, Rosario Fazio
We investigate the realization of a simple solid-state quantum computer by implementing the Deutsch-Jozsa algorithm in a system of Josephson charge qubits. Starting from a procedure to carry out the one-qubit Deutsch-Jozsa algorithm we show how the N-qubit version of the Bernstein-Vazirani algorithm can be realized. For the implementation of the three-qubit
A perspectival version of the modal interpretation of quantum mechanics and the origin of macroscopic behavior
quant-phGyula Bene, Dennis Dieks
We study the process of observation (measurement), within the framework of a `perspectival' (`relational', `relative state') version of the modal interpretation of quantum mechanics. We show that if we assume certain features of discreteness and determinism in the operation of the measuring device (which could be a part of the observer's nerv
John A. Drakopoulos, Theodore N. Tomaras
Assuming a cloning oracle, satisfiability, which is an NP complete problem, is shown to belong to $BPP^C$ and $BQP^C$ (depending on the ability of the oracle C to clone either a binary random variable or a qubit). The same result is extended in the case of an approximate cloning oracle, thus establishing that $NP \subseteq BPP^C \subseteq BQP^C$ and $NP \sub
Giuliano Benenti, Giulio Casati, Simone Montangero, Dima L. Shepelyansky
We study the properties of eigenstates of an operating quantum computer which simulates the dynamical evolution in the regime of quantum chaos. Even if the quantum algorithm is polynomial in number of qubits $n_q$, it is shown that the ideal eigenstates become mixed and strongly modified by static imperfections above a certain threshold which drops exponenti
P. Warszawski, H. M. Wiseman, H. Mabuchi
Quantum trajectories describe the stochastic evolution of an open quantum system conditioned on continuous monitoring of its output, such as by an ideal photodetector. Here we derive (non-Markovian) quantum trajectories for realistic photodetection, including the effects of efficiency, dead time, bandwidth, electronic noise, and dark counts. We apply our the
Sameen Ahmed Khan, Modesto PUSTERLA
An interpretation of the formation of halo in accelerators based on quantum-like theory by a diffraction model is given in terms of the transversal beam motion. Physical implications of the longitudinal dynamics are also examined
Fran De Aquino
It was shown that there is a practical possibility of gravity control on electroluminescent (EL) materials (physics/0109060). We present here a type Gravitational Shielding based on an EL phosphor namely zinc sulfide doped with silver (ZnS:Ag) which can reduce the cost of the Gravitational Motor previously presented.
P. N. Burrows
I summarise the R&D programme on a nanosecond-timescale fast-feedback system for luminosity optimisation at the linear collider
A cluster partitioning method: determination of density matrices of solids and comparison with X-ray experiments
physics.chem-phSebastien Ragot, Jean-Michel Gillet, Pierre J Becker
In this paper we show that 1-electron properties such as Compton profiles and structure factors of crystals can be asymptotically retrieved through cluster-based calculations, followed by an appropriate partition of the 1-electron reduced density matrix (1RDM). This approach, conceptually simple, is checked with respects to both position and momentum spaces
Frank Wilczek
Fermi helped establish a new framework for understanding matter, based on quantum theory. This framework refines and improves traditional atomism in two crucial respects. First, the elementary constituents of matter belong to a very small number of classes, and all objects of a given class (e.g., all electrons) are rigorously identical, indeed indistinguisha
C. Figueira de Morisson Faria, I Rotter
We investigate high-harmonic generation in closed systems, using the two-level atom as a simplified model. By means of a windowed Fourier transform of the time-dependent dipole acceleration, we extract the main contributions to this process within a cycle of the driving field. We show that the patterns obtained can be understood by establishing a parallel be
Jinlan Wang, Guanghou Wang, Xiaoshuang Chen, Wei Lu
The structural and magnetic properties of Co$_{18-m}$Cu$_m$ ($0\leq m\leq 18$) clusters are investigated with a genetic algorithm and a $spd$-band model Hamiltonian in the unrestricted Hartree-Hock approximation respectively. In general, Cu atoms tend to occupy the surface, while Co atoms prefer to the interior of the clusters. Layered structures appear in s
Pavel Chapovsky
Enrichment of nuclear spin isomers of molecules by infrared radiation resonant to molecular rovibrational transition is considered. Special attention is given to the enrichment by light-induced crossing of far separated ortho and para states.
Juris Kalnins, Glen Lambertson, Harvey Gould
Polar molecules, in strong-field seeking states, can be transported and focused by an alternating sequence of electric field gradients that focus in one transverse direction while defocusing in the other. We show, by calculation and numerical simulation, how one may greatly improve the alternating gradient transport and focusing of molecules. We use a new op
E. Baldini-Neto, C. L. Lima, P. Van Isacker
An algebraic model is developed to calculate the T=0 and T=1 ground state binding energies for N=Z nuclei. The method is tested in the sd shell and is then extended to 28-50 shell which is currently the object of many experimental studies.
Sonia Bacca, Mario Andrea Marchisio, Nir Barnea, Winfried Leidemann
The total photoabsorption cross sections of 6He and 6Li are calculated microscopically with full inclusion of the six-nucleon final state interaction using semirealistic nucleon-nucleon potentials. The Lorentz Integral Transform (LIT) method and the effective interaction approach for the hyperspherical formalism are employed. While 6Li has a single broad gia
M. S. Fayache, J. P. Vary, B. R. Barrett, P. Navratil
Working in the framework of the ab-initio no-core shell model, we derive two-body effective interactions microscopically for specific harmonic-oscillator basis spaces from the realistic Argonne V8' nucleon-nucleon potential. However, our two-body effective interaction is only the dominant part of the A-body (A >= 3) effective interaction, which also cont
Analysing powers for the reaction $\vec{\rm n} {\rm p} \to {\rm p} {\rm p} π^{-}$ and for np elastic scattering from 270 to 570 MeV
nucl-exM. Daum, M. Finger, M. Finger,, J. Franz
The analysing power of the reaction ${\rm n}{\rm p} \to {\rm p}{\rm p} π^{-}$ for neutron energies between threshold and 570 MeV has been determined using a transversely polarised neutron beam at PSI. The reaction has been studied in a kinematically complete measurement using a time-of-flight spectrometer with large acceptance. Analysing powers have been det
Anton S. Desyatnikov, Yuri S. Kivshar
We introduce the concept of soliton clusters -- multi-soliton bound states in a homogeneous bulk optical medium, and reveal a key physical mechanism for their stabilization associated with a staircase-like phase distribution that induces a net angular momentum and leads to cluster rotation. The ringlike soliton clusters provide a nontrivial generalization of
M. A. Soloviev
We formulate an equivalence relation between nonlocal quantum fields, generalizing the relative locality which was studied by Borchers in the framework of local QFT. The Borchers classes are shown to allow a natural extension involving nonlocal fields with arbitrarily singular ultraviolet behavior. Our consideration is based on the systematic employment of t
M. A. Soloviev
We generalize the theory of Lorentz-covariant distributions to broader classes of functionals including ultradistributions, hyperfunctions, and analytic functionals with a tempered growth. We prove that Lorentz-covariant functionals with essential singularities can be decomposed into polynomial covariants and establish the possibility of the invariant decomp
Julien Sebag
We develop the theory of motivic integration for formal schemes
Gaetano Fiore
We briefly report on our result that, if there exists a realization of a Hopf algebra $H$ in a $H$-module algebra $A$, then their cross-product is equal to the product of $A$ itself with a subalgebra isomorphic to $H$ and commuting with $A$. We illustrate its application to the Euclidean quantum groups in $N\ge 3$ dimensions.
Claire Voisin
Summary: The Hodge conjecture asks whether rational Hodge classes on a smooth projective manifolds are generated by the classes of algebraic subsets, or equivalently by Chern classes of coherent sheaves. On a compact Kaehler manifold, Hodge conjecture is known to be false if algebraic subsets are replaced with analytic subsets. Here we show that it is even f
Tom Kennedy
The conjecture that the scaling limit of the two-dimensional self-avoiding walk (SAW) in a half plane is given by the stochastic Loewner evolution (SLE) with $κ=8/3$ leads to explicit predictions about the SAW. A remarkable feature of these predictions is that they yield not just critical exponents, but probability distributions for certain random variables
Allan L. Edmonds
For a closed 4-manifold X and closed 3-manifold M we investigate the smallest integer n (perhaps infinity) such that M embeds in the connected sum of n copies of X. It is proven that any lens space (or homology lens space) embeds topologically locally flatly in a connected sum of 8 copies of the complex projective plane.
Sophie Dourlens
In order to study the Hochschild cohomology of triangular algebras $\mathcal T$, we construct a spectral sequence, whose terms are parametrized by the length of the trajectories of the quiver associated with $\mathcal T$, and which converges to $HH^*(\mathcal T)$. We explicit its components, and its differentials which are sums of cup products. In case $n=3$
R. V. Gurjar, C. R. Pradeep, D. -Q. Zhang
In this paper we prove that a normal Gorenstein surface dominated by the projective plane P^2 is isomorphic to a quotient P^2/G, where G is a finite group of automorphisms of P^2 (except possibly for one surface V_8'). We can completely classify all such quotients. Some natural conjectures when the surface is not Gorenstein are also stated.
J. M. Ancochea, R. Campoamor
We compute the first and second cohomology groups with coefficients in the adjoint module of frobeniusian model algebras whose parameters move in a dense open subset of $\mathbb{C}^{p-1}$, and obtain upper bounds for the dimension of cohomology groups of frobeniusian Lie algebras. Moreover, it is shown that for a dense open subset of $\mathbb{C}^{p-1}$ the d
Francois Ebobisse, Mohameden Ould Ahmedou
In this paper we use an algebraic topological argument due to Bahri and Coron to show how the topology of the domain influences the existence of positive solutions of some fourth order elliptic equation involving the critical Sobolev exponent.
Jan Fricke
In "Unsolved Problems in Number Theory" problem D22 Richard Guy asked for the existence of simplices with integer lengths, areas, volumes... In dimension two this is well known, these triangles are called Heron triangles. Here I will present my results on Heron tetrahedra, their connection to the existence of an integer box (problem D18), the tools f
Saharon Shelah
We deal with an iteration theorem of forcing notion with a kind of countable support of nice enough forcing notion which is proper aleph_2-c.c. forcing notions. We then look at some special cases (Q_D 's preceded by random forcing).
Saharon Shelah
We show that, consistently, there is an ultrafilter F on omega such that if N^l_n=(P^l_n cup Q^l_n,P^l_n,Q^l_n,R^l_n) (for l =1,2, n< omega), P^l_n cup Q^l_n subseteq omega, and prod_{n<omega} N^1_n/F and prod_{n< omega}N^2_n/F are isomorphic models of the canonical theory t^ind of the strong independence property, then every isomorphism from prod_{n<omega}
Tom Hadfield
We compare the K-theory and K-homology of the well known CAR algebra. While the $K_0$ group is infinitely generated, we shows that it pairs identically to zero with even Fredholm modules over the algebra. We show further that in fact the even K-homology is trivial, while the odd K-homology is very large. These results give some insight into the K-homology of
Tom Hadfield
We study the K-homology of the rotation algebras $A_θ$ using the six term cyclic sequence for the K-homology of a crossed product by ${\bf Z}$. In the case where $θ$ is irrational we use Pimsner and Voiculescu's work on AF-embeddings of the $A_θ$ to search for the missing generator of the even K-homology.
Michael T. Lacey
Let $H_k$ be the one dimensional Hilbert transform computed in the direction $(1,2^k)$ in the plane. We show that the maximal operator $\sup_k |H_kf|$ maps $L^p$ of the plane into itself for $1<p<\infty$. The same result with the Hilbert transform replaced by the one dimensional maximal function was proved by Nagel, Stein and Wainger in 1978.
Raphael Bousso, Alexander Maloney, Andrew Strominger
The dS/CFT correspondence is illuminated through an analysis of massive scalar field theory in d-dimensional de Sitter space. We consider a one-parameter family of dS-invariant vacua related by Bogolyubov transformations and compute the corresponding Green functions. It is shown that none of these Green functions correspond to the one obtained by analytic co
E. Farhi, N. Graham, R. L. Jaffe, H. Weigel
We search for static solitons stabilized by heavy fermions in a 3+1 dimensional Yukawa model. We compute the renormalized energy functional, including the exact one-loop quantum corrections, and perform a variational search for configurations that minimize the energy for a fixed fermion number. We compute the quantum corrections using a phase shift parameter
H. Reinhardt
The topology of center vortices is studied. For this purpose it is sufficient to consider mathematically idealised vortices, defined in a gauge invariant way as closed (infinitely thin) flux surfaces (in D=4 dimensions) which contribute the n'th power of a non-trivial center element to Wilson loops when they are n-foldly linked to the latter. In ordinary
Marie-Noelle Celerier, Laurent Nottale
The theory of scale relativity provides a new insight into the origin of fundamental laws in physics. Its application to microphysics allows to recover quantum mechanics as mechanics on a non-differentiable (fractal) space-time. The Schrödinger and Klein-Gordon equations have already been demonstrated as geodesic equations in this framework. We propose here