Results for "H. Atmacan"

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Evidence for the decay $B^{0}\to ηη$Sep 12 2016We report a search for $B^{0}\to \eta \eta $ with a data sample corresponding to an integrated luminosity of $698 \,{\rm fb}^{-1}$ containing $753 \times 10^{6}$ $B\bar{B}$ pairs collected at the $\Upsilon(4S)$ resonance with the Belle detector at the ... More
Measurement of the $τ$ lepton polarization in the decay ${\bar B} \rightarrow D^* τ^- {\bar ν_τ}$Aug 23 2016We report the first measurement of the $\tau$ lepton polarization in the decay ${\bar B} \rightarrow D^* \tau^- {\bar\nu_{\tau}}$ as well as a new measurement of the ratio of the branching fractions $R(D^{*}) = \mathcal{B}({\bar B} \rightarrow D^* \tau^- ... More
Precise determination of the CKM matrix element $\left| V_{cb}\right|$ with $\bar B^0 \to D^{*\,+} \, \ell^- \, \bar ν_\ell$ decays with hadronic tagging at BelleFeb 06 2017Feb 14 2017The precise determination of the CKM matrix element $\left| V_{cb}\right|$ is important for carrying out tests of the flavour sector of the Standard Model. In this article we present a preliminary analysis of the $\bar B^0 \to D^{*\,+} \, \ell^- \, \bar ... More
Study of χ_{bJ}(1P) Properties in the Radiative Υ(2S) DecaysJun 03 2016We report a study of radiative decays of \chi_{bJ}(1P)(J=0,1,2) mesons into 74 hadronic final states comprising charged and neutral pions, kaons, protons; out of these, 41 modes are observed with at least 5 standard deviation significance. Our measurements ... More
Measurement of the branching ratio of $\bar{B}^0 \rightarrow D^{*+} τ^- \barν_τ$ relative to $\bar{B}^0 \rightarrow D^{*+} \ell^- \barν_{\ell}$ decays with a semileptonic tagging methodMar 22 2016We report a measurement of ratio ${\cal R}(D^*) = {\cal B}(\bar{B}^0 \rightarrow D^{*+} \tau^- \bar{\nu}_{\tau})/{\cal B}(\bar{B}^0 \rightarrow D^{*+} \ell^- \bar{\nu}_{\ell})$, where $\ell$ denotes an electron or a muon. The results are based on a data ... More
Measurement of CKM Matrix Element $|V_{cb}|$ from $\bar{B} \to D^{*+} \ell^{-} \barν_\ell$Sep 10 2018Nov 19 2018We present a new measurement of the CKM matrix element $|V_{cb}|$ from $ B^{0} \rightarrow D^{*}\ell \nu$ decays, reconstructed with full Belle data set ($711 \, \rm fb^{-1}$). Two form factor parameterisations, based on work by the CLN and BGL groups, ... More
Measurements of branching fraction and $CP$ asymmetry of the $\bar{B}^{0}(B^{0})\to K^{0}_{S}K^{\mp}π^{\pm}$ decay at BelleJul 18 2018Sep 03 2018We report the measurement of the branching fraction and $CP$ asymmetry for the $\bar{B}^{0}(B^{0})\to K^{0}_{S}K^{\mp}\pi^{\pm}$ decay. The analysis is performed on a data sample of 711 $\rm{fb}^{-1}$ collected at the $\Upsilon(4S)$ resonance with the ... More
Study of charmless decays $B^{\pm} \to K^{0}_{S} K^{0}_{S} h^{\pm}$ ($h=K,π$) at BelleAug 01 2018We report a search for charmless hadronic decays of charged $B$ mesons to the final states $K^{0}_{S} K^{0}_{S} K^{\pm}$ and $K^{0}_{S} K^{0}_{S} \pi^{\pm}$ . The results are based on a $711 {fb}^{-1}$ data sample that contains $772 \times 10^6$ $B \bar{B}$ ... More
Evidence for the h_b(1P) meson in the decay Upsilon(3S) --> pi0 h_b(1P)Feb 22 2011Oct 17 2011Using a sample of 122 million Upsilon(3S) events recorded with the BaBar detector at the PEP-II asymmetric-energy e+e- collider at SLAC, we search for the $h_b(1P)$ spin-singlet partner of the P-wave chi_{bJ}(1P) states in the sequential decay Upsilon(3S) ... More
Search for hadronic decays of a light Higgs boson in the radiative decay Upsilon --> gamma A0Aug 17 2011We search for hadronic decays of a light Higgs boson (A0) produced in radiative decays of an Upsilon(2S) or Upsilon(3S) meson, Upsilon --> gamma A0. The data have been recorded by the BABAR experiment at the Upsilon(3S) and Upsilon(2S) center of mass ... More
Emergent states in dense systems of active rods: from swarming to turbulenceApr 02 2012Dense suspensions of self-propelled rod-like particles exhibit a fascinating variety of non-equilibrium phenomena. By means of computer simulations of a minimal model for rigid self-propelled colloidal rods with variable shape we explore the generic diagram ... More
Aggregation of self-propelled colloidal rods near confining wallsSep 03 2008Non-equilibrium collective behavior of self-propelled colloidal rods in a confining channel is studied using Brownian dynamics simulations and dynamical density functional theory. We observe an aggregation process in which rods self-organize into transiently ... More
The Belle II Physics BookAug 31 2018Oct 24 2018We present the physics program of the Belle II experiment, located on the intensity frontier SuperKEKB e+e- collider. Belle II collected its first collisions in 2018, and is expected to operate for the next decade. It is anticipated to collect 50/ab of ... More
Rhythmic cluster generation in strongly driven colloidal dispersionsJun 28 2006We study the response of a nematic colloidal dispersion of rods to a driven probe particle which is dragged with high speed through the dispersion perpendicular to the nematic director. In front of the dragged particle, clusters of rods are generated ... More
Superradiant cascade emissions in an atomic ensemble via four-wave mixingJan 21 2015May 04 2015We investigate superradiant cascade emissions from an atomic ensemble driven by two-color classical fields. The correlated pair of photons (signal and idler) is generated by adiabatically driving the system with large-detuned light fields via four-wave ... More
Spectral analysis for cascade-emission-based quantum communication in atomic ensemblesMar 11 2014The ladder configuration of atomic levels provides a source for telecom photons (signal) from the upper atomic transition. \ For rubidium and cesium atoms, the signal field has the range around 1.3-1.5 $\mu$m that can be coupled to an optical fiber and ... More
Positive-P phase space method simulation in superradiant emission from a cascade atomic ensembleJan 12 2012The superradiant emission properties from an atomic ensemble with cascade level configuration is numerically simulated. The correlated spontaneous emissions (signal then idler fields) are purely stochastic processes which are initiated by quantum fluctuations. ... More
AdS/CFT correspondence in the Euclidean contextNov 02 2006May 23 2007We study two possible prescriptions for AdS/CFT correspondence by means of functional integrals. The considerations are non-perturbative and reveal certain divergencies which turn out to be harmless, in the sense that reflection-positivity and conformal ... More
Correlation Energy Estimators based on Møller-Plesset Perturbation TheoryMar 05 1996Some methods for the convergence acceleration of the M{\o}ller-Plesset perturbation series for the correlation energy are discussed. The order-by-order summation is less effective than the Feenberg series. The latter is obtained by renormalizing the unperturbed ... More
N=8 matter coupled AdS_3 supergravitiesJun 18 2001Following the recent construction of maximal (N=16) gauged supergravity in three dimensions, we derive gauged D=3, N=8 supergravities in three dimensions as deformations of the corresponding ungauged theories with scalar manifolds SO(8,n)/(SO(8)x SO(n)). ... More
Maximal gauged supergravity in three dimensionsOct 11 2000Jan 07 2001We construct maximally supersymmetric gauged N=16 supergravity in three dimensions, thereby obtaining an entirely new class of AdS supergravities. These models are not derivable from any known higher-dimensional theory, indicating the existence of a new ... More
Whitham Prepotential and SuperpotentialDec 30 2003Jan 24 2004N=2 supersymmetric U(N) Yang-Mills theory softly broken to N=1 by the superpotential of the adjoint scalar fields is discussed from the viewpoint of the Whitham deformation theory for prepotential. With proper identification of the superpotential we derive ... More
Surface anisotropy in nanomagnets: transverse or Néel ?Jul 17 2003Mar 31 2004Through the hysteresis loop and magnetization spatial distribution we study and compare two models for surface anisotropy in nanomagnets: a model with transverse anisotropy axes and N\'eel's model. While surface anisotropy in the transverse model induces ... More
String-Scale BaryogenesisMar 25 1997Mar 26 1997Baryogenesis scenarios at the string scale are considered. The observed baryon to entropy ratio, $n_B /s \sim 10^{-10}$, can be explained in these scenarios.
Thermodynamic of universe with a varying dark energy componentMay 04 2015Aug 03 2015We consider a FRW universe filled by a dark energy candidate together with other possible sources which may include the baryonic and non-baryonic matters. Thereinafter, we consider a situation in which the cosmos sectors do not interact with each other. ... More
Analysis of the thermal cross section of the capture reaction 13C(n,gamma)14COct 02 1997We investigate the thermal cross section of the reaction 13C(n,gamma)14}C which takes place in the helium burning zones of red giant star as well as in the nucleosynthesis of Inhomogeneous Big Bang models. We find that we can reproduce the experimentally ... More
Erroneous solution of three-dimensional (3D) simple orthorhombic Ising latticesSep 04 2012Jun 18 2013The first paper is an invited comment on arXiv:1110.5527 presented at Hypercomplex Seminar 2012 and on sixteen earlier published papers by Zhidong Zhang and Norman H. March. All these works derive from an erroneous solution of the three-dimensional Ising ... More
Rejoinder on "Conjectures on exact solution of three-dimensional (3D) simple orthorhombic Ising lattices"Jan 19 2009Mar 30 2009It is shown that the arguments in the reply of Z.-D. Zhang (arXiv:0812.0194) to the comment arXiv:0811.1802 defending his conjectures in arXiv:0705.1045 are invalid. His conjectures have been thoroughly disproved.
The two-fermion vector potential of constraint theory from Feynman diagramsOct 16 1995The relativistic fermion-antifermion bound state vector potential of constraint theory is calculated, in perturbation theory, by means of the Lippmann-Schwinger type equation that relates it to the scattering amplitude. Leading contributions of n-photon ... More
Energy and decay width of the pi-K atomMay 24 2006The energy and decay width of the pi-K atom are evaluated in the framework of the quasipotential-constraint theory approach. The main electromagnetic and isospin symmetry breaking corrections to the lowest-order formulas for the energy shift from the ... More
Molecular dynamics simulation of aging in amorphous silicaDec 06 1999By means of molecular dynamics simulations we examine the aging process of a strong glass former, a silica melt modeled by the BKS potential. The system is quenched from a temperature above to one below the critical temperature, and the potential energy ... More
An indefinite metric model for interacting quantum fields with non-stationary background gravitationAug 25 2004We consider a relativistic Ansatz for the vacuum expectation values (VEVs) of a quantum field on a globally hyperbolic space-time which is motivated by certain Euclidean field theories. The Yang-Feldman asymptotic condition w.r.t. a "in"-field in a quasi-free ... More
Series Prediction based on Algebraic ApproximantsJul 12 2011It is described how the Hermite-Pad\'e polynomials corresponding to an algebraic approximant for a power series may be used to predict coefficients of the power series that have not been used to compute the Hermite-Pad\'e polynomials. A recursive algorithm ... More
Boundary blow-up solutions of elliptic equations involving regional fractional LaplacianFeb 09 2016In this paper, we study existence of boundary blow-up solutions for elliptic equations involving regional fractional Laplacian. We also discuss the optimality of our results.
A 5D noncompact Kaluza -Klein cosmology in the presence of Null perfect fluidMay 18 2010Jun 08 2011For the description of the early inflation, and acceleration expansion of the Universe, compatible with observational data, the 5D noncompact Kaluza--Klein cosmology is investigated. It is proposed that the 5D space is filled with a null perfect fluid, ... More
Schwinger-Dyson and Large $N_{c}$ Loop Equation for Supersymmetric Yang-Mills TheoryApr 04 1996We derive an infinite sequence of Schwinger-Dyson equations for $N=1$ supersymmetric Yang-Mills theory. The fundamental and the only variable employed is the Wilson-loop geometrically represented in $N=1$ superspace: it organizes an infinite number of ... More
On pseudo B-Weyl operators and generalized Drazin invertibility for operator matricesMar 23 2015We introduce a new class which generalizes the class of B-Weyl operators. We say that $T\in L(X)$ is pseudo B-Weyl if $T=T_1\oplus T_2$ where $T_1$ is a Weyl operator and $T_2$ is a quasi-nilpotent operator. We show that the corresponding pseudo B-Weyl ... More
The infinite mass limit of the two-particle Green's function in QEDApr 07 1997The behavior of the two-particle Green's function in QED is analyzed in the limit when one of the particles becomes infinitely massive. It is found that the dependences of the Green's function on the relative times of the ingoing and outgoing particles ... More
Incorporation of anomalous magnetic moments in the two-body relativistic wave equations of constraint theoryJun 19 1996Using a Dirac-matrix substitution rule, applied to the electric charge, the anomalous magnetic moments of fermions are incorporated in local form in the two-body relativistic wave equations of constraint theory. The structure of the resulting potential ... More
The Early History of the Integrable Chiral Potts Model and the Odd-Even ProblemNov 26 2015Jan 18 2016In the first part of this paper I shall discuss the round-about way of how the integrable chiral Potts model was discovered about 30 years ago. As there should be more higher-genus models to be discovered, this might be of interest. In the second part ... More
Supereigenvalue Model and Dijkgraaf-Vafa ProposalApr 22 2003We present a variant of the supereigenvalue model proposed before by Alvarez-Gaume, Itoyama, Manes, and Zadra. This model derives a set of three planar loop equations which takes the same form as the set of three anomalous Ward-Takahashi identities on ... More
Scalar Levin-Type Sequence TransformationsMay 22 2000Sequence transformations are important tools for the convergence acceleration of slowly convergent scalar sequences or series and for the summation of divergent series. Transformations that depend not only on the sequence elements or partial sums $s_n$ ... More
Entropy of entanglement in continuous frequency space of the biphoton state from multiplexed cold atomic ensemblesJan 05 2016We consider a scheme of multiplexed cold atomic ensembles that generate a frequency-entangled biphoton state with controllable entropy of entanglement. The biphoton state consists of a telecommunication photon (signal) immediately followed by an infrared ... More
On K(E_9)Jul 08 2004We study the maximal compact subgroup K(E_9) of the affine Lie group E_9(9) and its on-shell realization as an R symmetry of maximal N=16 supergravity in two dimensions. We first give a rigorous definition of the group K(E_9), which lives on the double ... More
Compact and Noncompact Gauged Maximal Supergravities in Three DimensionsMar 06 2001Apr 21 2001We present the maximally supersymmetric three-dimensional gauged supergravities. Owing to the special properties of three dimensions -- especially the on-shell duality between vector and scalar fields, and the purely topological character of (super)gravity ... More
A nontrivial solvable noncommutative φ^3 model in 4 dimensionsMar 07 2006May 24 2006We study the quantization of the noncommutative selfdual \phi^3 model in 4 dimensions, by mapping it to a Kontsevich model. The model is shown to be renormalizable, provided one additional counterterm is included compared to the 2-dimensional case which ... More
Renormalization of the noncommutative phi^3 model through the Kontsevich modelDec 16 2005We point out that the noncommutative selfdual phi^3 model can be mapped to the Kontsevich model, for a suitable choice of the eigenvalues in the latter. This allows to apply known results for the Kontsevich model to the quantization of the field theory, ... More
Transition Amplitudes within the Stochastic Quantization SchemeSep 30 1993Quantum mechanical transition amplitudes are calculated within the stochastic quantization scheme for the free nonrelativistic particle, the harmonic oscillator and the nonrelativistic particle in a constant magnetic field; we close with free Grassmann ... More
Independent Component Analysis of Spatiotemporal ChaosMay 13 2005Two types of spatiotemporal chaos exhibited by ensembles of coupled nonlinear oscillators are analyzed using independent component analysis (ICA). For diffusively coupled complex Ginzburg-Landau oscillators that exhibit smooth amplitude patterns, ICA ... More
Pentaquark $Θ^+$ in nuclear matter and $Θ^+$ hypernucleiOct 17 2004Jul 05 2005We study the properties of the $\Theta^+$ in nuclear matter and $\Theta^+$ hypernuclei within the quark mean-field (QMF) model, which has been successfully used for the description of ordinary nuclei and $\Lambda$ hypernuclei. With the assumption that ... More
Gauge transformations in relativistic two-particle constraint theorySep 16 1996Using connection with quantum field theory, the infinitesimal covariant abelian gauge transformation laws of relativistic two-particle constraint theory wave functions and potentials are established and weak invariance of the corresponding wave equations ... More
Relativistic effects in the pionium lifetimeJun 23 1997The pionium decay width is evaluated in the framework of chiral perturbation theory and the relativistic bound state formalism of constraint theory. Corrections of order O(\alpha) are calculated with respect to the conventional lowest-order formula, in ... More
Comment on "Conjectures on exact solution of three-dimensional (3D) simple orthorhombic Ising lattices" [arXiv:0705.1045]Nov 12 2008Nov 22 2008It is shown that a recent article by Z.-D. Zhang [arXiv:0705.1045] is in error and violates well-known theorems.
A Simple Method to Reduce Thermodynamic Derivatives by ComputerJan 09 2014Studies in thermodynamics often require the reduction of some first or second order partial derivatives in terms of a smaller basic set. A simple algorithm to perform such a reduction is presented here, together with a review of earlier related works. ... More
Variational Calculation of Effective Classical Potential at $T \neq 0$ to Higher OrdersApr 16 1995Using the new variational approach proposed recently for a systematic improvement of the locally harmonic Feynman-Kleinert approximation to path integrals we calculate the partition function of the anharmonic oscillator for all temperatures and coupling ... More
Superradiant laser: Effect of long-ranged dipole-dipole interactionSep 02 2016We theoretically investigate the effect of long-ranged dipole-dipole interaction (LRDDI) on a superradiant laser (SL). This effect is induced from the atom-photon interaction in the dissipation process. In the bad-cavity limit usually performed to initiate ... More
Cooperative single-photon subradiant states in a three-dimensional atomic arrayJun 21 2016We propose a complete superradiant and subradiant states that can be manipulated and prepared in a three-dimensional atomic array. These subradiant states can be realized by absorbing a single photon and imprinting the spatially-dependent phases on the ... More
Effects of Spin Fluctuations in Quasi-One-Dimensional Organic SuperconductorsMay 05 1999We study the electronic states of quasi-one-dimensional organic conductors using the single band Hubbard model at half-filling. We treat the effects of the on-site Coulomb interaction by the fluctuation-exchange (FLEX) method, and calculate the phase ... More
Application of the Limit Cycle Model to Star Formation Histories in Spiral Galaxies: Variation among Morphological TypesMay 04 2000We propose a limit-cycle scenario of star formation history for any morphological type of spiral galaxies. It is known observationally that the early-type spiral sample has a wider range of the present star formation rate (SFR) than the late-type sample. ... More
On the extrapolation of perturbation seriesDec 21 2002We discuss certain special cases of algebraic approximants that are given as zeroes of so-called "effective characteristic polynomials" and their generalization to a multiseries setting. These approximants are useful for the convergence acceleration or ... More
The size-extensitivity of correlation energy estimators based on effective characteristic polynomialsApr 08 1997Estimators $\Pi n$ for the correlation energy can be computed as roots of effective characteristic polynomials of degree $n$. The coefficients of these polynomials are derived from the terms of the perturbation series of the energy. From a fourth-order ... More
Integrability and Canonical Structure of d=2, N=16 SupergravityApr 23 1998Jul 01 1998The canonical formulation of d=2, N=16 supergravity is presented. We work out the supersymmetry generators (including all higher order spinor terms) and the N=16 superconformal constraint algebra. We then describe the construction of the conserved non-local ... More
A focusable, convergent fast-electron beam from ultra-high-intensity laser-solid interactionsJan 29 2015A novel scheme for the creation of a convergent, or focussing, fast-electron beam generated from ultra-high-intensity laser-solid interactions is described. Self-consistent particle-in-cell simulations are used to demonstrate the efficacy of this scheme ... More
Inherent global stabilization of unstable local behavior in coupled map latticesJul 05 2004The behavior of two-dimensional coupled map lattices is studied with respect to the global stabilization of unstable local fixed points without external control. It is numerically shown under which circumstances such inherent global stabilization can ... More
Quark mean field model for nuclear matter and finite nucleiNov 15 1999We study nuclear matter and finite nuclei in terms of the quark mean field (QMF) model, in which we describe the nucleon using the constituent quark model. The meson mean fields, in particular the sigma meson, created by other nucleons act on quarks inside ... More
The relativistic two-body potentials of constraint theory from summation of Feynman diagramsFeb 07 1996The relativistic two-body potentials of constraint theory for systems composed of two spin-0 or two spin-1/2 particles are calculated, in perturbation theory, by means of the Lippmann-Schwinger type equation that relates them to the scattering amplitude. ... More
Theory of the Hall Coefficient and the Resistivity on the Layered Organic Superconductors κ-(BEDT-TTF)Nov 20 2000Feb 22 2001In the organic superconducting \kappa-(BEDT-TTF) compounds, various transport phenomena exhibit striking non-Fermi liquid behaviors, which should be the important clues to understanding the electronic state of this system. Especially, the Hall coefficient ... More
Thermodynamical description of modified generalized Chaplygin gas model of dark energyApr 10 2015May 17 2016We consider a universe filled by a modified generalized Chaplygin gas together with a pressureless dark matter component. We get a thermodynamical interpretation for the modified generalized Chaplygin gas confined to the apparent horizon of FRW universe, ... More
Stabilization of causally and non-causally coupled map latticesJul 07 2004Two-dimensional coupled map lattices have global stability properties that depend on the coupling between individual maps and their neighborhood. The action of the neighborhood on individual maps can be implemented in terms of "causal" coupling (to spatially ... More
Asymptotic function for multi-growth surfaces using power-law noiseNov 06 2002Numerical simulations are used to investigate the multiaffine exponent $\alpha_q$ and multi-growth exponent $\beta_q$ of ballistic deposition growth for noise obeying a power-law distribution. The simulated values of $\beta_q$ are compared with the asymptotic ... More
Study of $Λ$ hypernuclei in the quark mean field modelApr 24 2001Jul 11 2001We extend the quark mean field model to the study of $\Lambda$ hypernuclei. Without adjusting parameters, the properties of $\Lambda$ hypernuclei can be described reasonably well. The small spin-orbit splittings for $\Lambda$ in hypernuclei are achieved, ... More
Comment on `Mathematical structure of the three-dimensional (3D) Ising model'Jul 06 2013The review paper by Zhang Zhi-Dong contains many errors and is based on several earlier works that are equally wrong.
Scalings between Physical and their Observationally related Quantities of Merger RemnantsSep 07 2005We present scaling relations between the virial velocity (V) and the one-dimensional central velocity dispersion (Sig0); the gravitational radius (Rv) and the effective radius (Re); and the total mass (M) and the luminous mass (ML) found in N-body simulations ... More
B2BII - Data conversion from Belle to Belle IISep 28 2018We describe the conversion of simulated and recorded data by the Belle experiment to the Belle~II format with the software package \texttt{b2bii}. It is part of the Belle~II Analysis Software Framework. This allows the validation of the analysis software ... More
Characterizing arbitrarily slow convergence in the method of alternating projectionsOct 12 2007In 1997, Bauschke, Borwein, and Lewis have stated a trichotomy theorem that characterizes when the convergence of the method of alternating projections can be arbitrarily slow. However, there are two errors in their proof of this theorem. In this note, ... More
Weak Quantum Theory: Complementarity and Entanglement in Physics and BeyondApr 23 2001Nov 21 2001The concepts of complementarity and entanglement are considered with respect to their significance in and beyond physics. A formally generalized, weak version of quantum theory, more general than ordinary quantum theory of material systems, is outlined ... More
CP Asymmetry for Inclusive Decay $B \to X_d + γ$ in the Minimal Supersymmetric Standard ModelJun 02 1999Aug 20 1999We study the inclusive rare decay $B\to X_d+\gamma$ in the supergravity inspired Minimal Supersymmetric Standard Model and compute the CP-asymmetry in the decay rates. We show that there exist two phenomenologically acceptable sets of SUSY parameters: ... More
Abrupt Emergence of Pressure-Induced Superconductivity of 34 K in SrFe2As2: A Resistivity Study under PressureOct 27 2008Nov 19 2008We report resistivity measurement under pressure in single crystals of SrFe_2As_2, which is one of the parent materials of Fe-based superconductors. The structural and antiferromagnetic (AFM) transition of T_0 = 198 K at ambient pressure is suppressed ... More
Feynman graphs for non-Gaussian measuresJan 12 2005Nov 30 2006Partition- and moment functions for a general (not necessarily Gaussian) functional measure that is perturbed by a Gibbs factor are calculated using generalized Feynman graphs. From the graphical calculus, a new notion of Wick ordering arises, that coincides ... More
Feynman graph representation of the perturbation series for general functional measuresAug 20 2004A representation of the perturbation series of a general functional measure is given in terms of generalized Feynman graphs and -rules. The graphical calculus is applied to certain functional measures of L\'evy type. A graphical notion of Wick ordering ... More
Asymptotic Analysis of High-Contrast Phononic Crystals and a Criterion for the Band-Gap OpeningSep 30 2006We investigate the band-gap structure of the frequency spectrum for elastic waves in a high-contrast, two-component periodic elastic medium. We consider two-dimensional phononic crystals consisting of a background medium which is perforated by an array ... More
The System of Multi Color-flux-tubes in the Dual Ginzburg-Landau TheoryFeb 27 1996We study the system of multi color-flux-tubes in terms of the dual Ginzburg -Landau theory. We consider two ideal cases, where the directions of all the color-flux-tubes are the same in one case and alternative in the other case for neighboring flux-tubes. ... More
Search for $η$-bound NucleiAug 17 2010The $\eta$ meson can be bound to atomic nuclei. Experimental search is discussed in the form of final state interaction for the reactions $dp\to{^3\text{He}}\eta$ and $dd\to{^4\text{He}}\eta$. For the latter case tensor polarized deuterons were used in ... More
Physics at COSYNov 21 2004The COSY accelerator in J\'ulich is presented together with its internal and external detectors. The physics programme performed recently is discussed with emphasis on strangeness physics.
Vortex Origin of Tricritical Point in Ginzburg-Landau TheorySep 16 2005Motivated by recent experimental progress in the critical regime of high-$T_c$ superconductors we show how the tricritical point in a superconductor can be derived from the Ginzburg-Landau theory as a consequence of vortex fluctuations. Our derivation ... More
Vortex Line Nucleation of First-Order Transition U(1)-Symmetric Field SystemsNov 20 1998We show that in field systems with U(1)-symmetry, first-order transitions are nucleated by vortex lines, not bubbles, thus calling for a reinvestigation of the Kibble mechanism for the phase transition of the early universe.
Hubbard-Stratonovich Transformation: Successes, Failure, and CureApr 27 2011We recall the successes of the Hubbard-Stratonovich Transformation (HST) of many-body theory, point out its failure to cope with competing channels of collective phenomena and show how to overcome this by Variational Perturbation Theory. That yields exponentially ... More
Status and perspectives of sin2alpha measurementsJul 23 2003In the neutral B meson system, it is possible to measure the CKM angle alpha using the decay mode b -> u ubar d in the presence of pollution from gluonic b -> d penguin decays. Here the recent status of the measurements of CP-violating asymmetry parameters ... More
Self--Dual Supergravity and Supersymmetric Yang--Mills Coupled to Green--Schwarz SuperstringNov 10 1992Nov 10 1992We present the {\it canonical} set of superspace constraints for self-dual supergravity, a ``self-dual'' tensor multiplet and a self-dual Yang-Mills multiplet with $~N=1~$ supersymmetry in the space-time with signature $(+,+,-,-)$. For this set of constraints, ... More
Transmission delay times of localized wavesMar 05 2001We investigate the effects of wave localization on the delay time tau (frequency sensitivity of the scattering phase shift) of a wave transmitted through a disordered wave guide. Localization results in a separation tau=chi+chi' of the delay time into ... More
Didactic derivation of the special theory of relativity from the Klein-Gordon equationJun 27 2014Jul 31 2014We present a didactic derivation of the special theory of relativity in which Lorentz transformations are `discovered' as symmetry transformations of the Klein-Gordon equation. The interpretation of Lorentz boosts as transformations to moving inertial ... More
Novel exact charged mass distribution in classical field theory and the notion of point-like elementary electric chargeAug 20 2014Feb 23 2016The existence of stable, charged elementary 'point particles' still is a basically unsolved puzzle in theoretical physics. E.g., in quantum electrodynamics the infinite self-energy of the Dirac point electron is 'swept under the carpet' by renormalizing ... More
Valuation of path-dependent American options using a Monte Carlo approachJan 12 1998It is shown how to obtain accurate values for American options using Monte Carlo simulation. The main feature of the novel algorithm consists of tracking the boundary between exercise and hold regions via optimization of a certain payoff function. We ... More
Recent studies of Charmonium Decays at CLEONov 13 2007Nov 16 2007Recent results on Charmonium decays are reviewed which includes two-, three- and four-body decays of $\chi_{cJ}$ states, observations of Y(4260) through $\pi\pi J/\psi$ transitions, precise measurements of $M(D^0)$, $M(\eta)$ as well as $\mathcal{B}(\eta\to ... More
The Fundamental Constants in PhysicsFeb 17 2009We discuss the fundamental constants of physics in the Standard Model and possible changes of these constants on the cosmological time scale. The Grand Unification of the strong, electromagnetic and weak interactions implies relations between the time ... More
Flavor Symmetries, Neutrino Masses and Neutrino MixingFeb 07 2008We discuss the neutrino mixing, using the texture 0 mass matrices, which work very well for the quarks. The solar mixing angle is directly linked to the mass ratio of the first two neutrinos. The neutrino masses are hierarchical, but the mass ratios turn ... More
In-Medium Similarity Renormalization Group for Closed and Open-Shell NucleiJul 23 2016We present a pedagogical introduction to the In-Medium Similarity Renormalization Group (IM-SRG) framework for ab initio calculations of nuclei. The IM-SRG performs continuous unitary transformations of the nuclear many-body Hamiltonian in second-quantized ... More
On gravitational dressing of renormalization group beta-functions beyond lowest order of perturbation theoryOct 12 1994Based on considerations in conformal gauge I derive up to nextleading order a relation between the coefficients of beta-functions in 2D renormalizable field theories before and after coupling to gravity. The result implies a coupling constant dependence ... More
The Density Profile of Massive Galaxy Clusters from Weak LensingOct 20 2003We use measurements of weak gravitational shear around a sample of massive galaxy clusters at z = 0.3 to constrain their average radial density profile. Our results are consistent with the density profiles of CDM halos in numerical simulations and inconsistent ... More
Scaling of N-body calculationsDec 14 2000We report results of collisional N-body simulations aimed to study the N-dependance of the dynamical evolution of star clusters. Our clusters consist of equal-mass stars and are in virial equilibrium. Clusters moving in external tidal fields and clusters ... More