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Arwed Schiller - One of the best experts on this subject based on the ideXlab platform.

  • Compact Q=2 Abelian Higgs model in the London limit: Vortex-monopole chains and the Photon Propagator
    Physical Review D, 2005
    Co-Authors: M. N. Chernodub, E.-m. Ilgenfritz, R. Feldmann, Arwed Schiller
    Abstract:

    The confining and topological properties of the compact Abelian Higgs model with doubly-charged Higgs field in three space-time dimensions are studied. We consider the London limit of the model. We show that the monopoles are forming chainlike structures (kept together by Abrikosov-Nielsen-Olesen vortices), the presence of which is essential for getting simultaneously permanent confinement of singly-charged particles and breaking of the string spanned between doubly-charged particles. In the confinement phase, the chains are forming percolating clusters, while in the deconfinement (Higgs) phase, the chains are of finite size. The described picture is in close analogy with the synthesis of the Abelian monopole and the center vortex pictures in confining non-Abelian gauge models. The screening properties of the vacuum are studied by means of the Photon Propagator in the Landau gauge.

  • Photon Propagator in compact(2+1)-dimensional QED: The effect of wrapping Dirac strings
    Physical Review D, 2004
    Co-Authors: M. N. Chernodub, E.-m. Ilgenfritz, Arwed Schiller
    Abstract:

    We discuss the influence of closed Dirac strings on the Photon Propagator in the Landau gauge emerging from a study of the compact U(1) gauge model in 2+1 dimensions. This gauge also minimizes the total length of the Dirac strings. Closed Dirac strings are stable against local gauge-fixing algorithms only due to the torus boundary conditions of the lattice. We demonstrate that these left-over Dirac strings are responsible for the previously observed unphysical behavior of the Propagator of space-like Photons (D_T) in the deconfinement (high temperature) phase. We show how one can monitor the number N_3 of thermal Dirac strings which allows to separate the Propagator measurements into N_3 sectors. The Propagator in N_3 \neq 0 sectors is characterized by a non--zero mass and an anomalous dimension similarly to the confinement phase. Both mass squared and anomalous dimension are found to be proportional to N_3. Consequently, in the N_3=0 sector the unphysical behavior of the D_T Photon Propagator is cured and the deviation from the free massless Propagator disappears.

  • More on String Breaking in the 3D Abelian Higgs Model: the Photon Propagator
    Physics Letters B, 2003
    Co-Authors: M. N. Chernodub, E.-m. Ilgenfritz, Arwed Schiller
    Abstract:

    We study the Landau gauge Photon Propagator in the three--dimensional Abelian Higgs model with compact gauge field and fundamentally charged matter in the London limit. The total gauge field is split into singular and regular parts. On the confinement side of the string breaking crossover the momentum dependence of the total Propagator is characterized by an anomalous dimension similarly to 3D compact QED. At the crossover and throughout the Higgs region the anomalous dimension disappears. This result perfectly agrees with recent observations that the monopole--antimonopole plasma leads to nonzero anomalous dimension and the presence of the matter fields causes monopole pairing into dipole bound states. The Yukawa mass characterizing the Propagator part from regular gauge fields is non-vanishing at the Higgs side and coincides with the mass found for the total Propagator. The regular gauge field without anomalous dimension becomes massless at the crossover and in the confinement region.

  • Monopoles, confinement and the Photon Propagator in QED3
    Nuclear Physics B - Proceedings Supplements, 2003
    Co-Authors: M. N. Chernodub, E.-m. Ilgenfritz, Arwed Schiller
    Abstract:

    Abstract We study the lattice gauge boson Propagator of3D compact QED in Landau gauge at zero and non-zero temperature. Non-perturbative effects are reflected by the generation of a massm, by an anomalous dimension α and by the Photon wave function renormalisationZ. These effects can be attributed to monopoles: they are absent in the Propagator of the regular part of the gauge field. The role of Gribov copies is carefully investigated.

  • Confinement, Deconfinement and the Photon Propagator in 3d cQED on the Lattice
    Quark Confinement and the Hadron Spectrum V, 2003
    Co-Authors: M. N. Chernodub, E.-m. Ilgenfritz, Arwed Schiller
    Abstract:

    We report on a lattice study of the gauge boson Propagator of 3D compact QED in Landau gauge at zero and finite temperature. Non-perturbative effects are reflected by the generation of a mass m and by an anomalous dimension alpha. These effects can be attributed to monopoles and are absent in the Propagator of the regular part of the gauge field.

M. N. Chernodub - One of the best experts on this subject based on the ideXlab platform.

  • Compact Q=2 Abelian Higgs model in the London limit: Vortex-monopole chains and the Photon Propagator
    Physical Review D, 2005
    Co-Authors: M. N. Chernodub, E.-m. Ilgenfritz, R. Feldmann, Arwed Schiller
    Abstract:

    The confining and topological properties of the compact Abelian Higgs model with doubly-charged Higgs field in three space-time dimensions are studied. We consider the London limit of the model. We show that the monopoles are forming chainlike structures (kept together by Abrikosov-Nielsen-Olesen vortices), the presence of which is essential for getting simultaneously permanent confinement of singly-charged particles and breaking of the string spanned between doubly-charged particles. In the confinement phase, the chains are forming percolating clusters, while in the deconfinement (Higgs) phase, the chains are of finite size. The described picture is in close analogy with the synthesis of the Abelian monopole and the center vortex pictures in confining non-Abelian gauge models. The screening properties of the vacuum are studied by means of the Photon Propagator in the Landau gauge.

  • Photon Propagator in compact(2+1)-dimensional QED: The effect of wrapping Dirac strings
    Physical Review D, 2004
    Co-Authors: M. N. Chernodub, E.-m. Ilgenfritz, Arwed Schiller
    Abstract:

    We discuss the influence of closed Dirac strings on the Photon Propagator in the Landau gauge emerging from a study of the compact U(1) gauge model in 2+1 dimensions. This gauge also minimizes the total length of the Dirac strings. Closed Dirac strings are stable against local gauge-fixing algorithms only due to the torus boundary conditions of the lattice. We demonstrate that these left-over Dirac strings are responsible for the previously observed unphysical behavior of the Propagator of space-like Photons (D_T) in the deconfinement (high temperature) phase. We show how one can monitor the number N_3 of thermal Dirac strings which allows to separate the Propagator measurements into N_3 sectors. The Propagator in N_3 \neq 0 sectors is characterized by a non--zero mass and an anomalous dimension similarly to the confinement phase. Both mass squared and anomalous dimension are found to be proportional to N_3. Consequently, in the N_3=0 sector the unphysical behavior of the D_T Photon Propagator is cured and the deviation from the free massless Propagator disappears.

  • More on String Breaking in the 3D Abelian Higgs Model: the Photon Propagator
    Physics Letters B, 2003
    Co-Authors: M. N. Chernodub, E.-m. Ilgenfritz, Arwed Schiller
    Abstract:

    We study the Landau gauge Photon Propagator in the three--dimensional Abelian Higgs model with compact gauge field and fundamentally charged matter in the London limit. The total gauge field is split into singular and regular parts. On the confinement side of the string breaking crossover the momentum dependence of the total Propagator is characterized by an anomalous dimension similarly to 3D compact QED. At the crossover and throughout the Higgs region the anomalous dimension disappears. This result perfectly agrees with recent observations that the monopole--antimonopole plasma leads to nonzero anomalous dimension and the presence of the matter fields causes monopole pairing into dipole bound states. The Yukawa mass characterizing the Propagator part from regular gauge fields is non-vanishing at the Higgs side and coincides with the mass found for the total Propagator. The regular gauge field without anomalous dimension becomes massless at the crossover and in the confinement region.

  • Monopoles, confinement and the Photon Propagator in QED3
    Nuclear Physics B - Proceedings Supplements, 2003
    Co-Authors: M. N. Chernodub, E.-m. Ilgenfritz, Arwed Schiller
    Abstract:

    Abstract We study the lattice gauge boson Propagator of3D compact QED in Landau gauge at zero and non-zero temperature. Non-perturbative effects are reflected by the generation of a massm, by an anomalous dimension α and by the Photon wave function renormalisationZ. These effects can be attributed to monopoles: they are absent in the Propagator of the regular part of the gauge field. The role of Gribov copies is carefully investigated.

  • Confinement, Deconfinement and the Photon Propagator in 3d cQED on the Lattice
    Quark Confinement and the Hadron Spectrum V, 2003
    Co-Authors: M. N. Chernodub, E.-m. Ilgenfritz, Arwed Schiller
    Abstract:

    We report on a lattice study of the gauge boson Propagator of 3D compact QED in Landau gauge at zero and finite temperature. Non-perturbative effects are reflected by the generation of a mass m and by an anomalous dimension alpha. These effects can be attributed to monopoles and are absent in the Propagator of the regular part of the gauge field.

Yuko Okamoto - One of the best experts on this subject based on the ideXlab platform.

  • Asymptotic Photon Propagator and higher-order QED Callan-Symanzik β function
    Physics Letters B, 1991
    Co-Authors: H. Kawai, T. Kinoshita, Yuko Okamoto
    Abstract:

    The QED Callan-Symanzik β function is calculated for a certain class of higher-order Photon self-energy diagrams within the framework of perturbative QED. It is found that the formulation of de Rafael and Rosner is valid up to the sixth order but must be modified from the eighth order on. Correction terms are evaluated explicitly. The result, applied a renormalization group calculation of an eighth-order contribution to the muon anomalous magnetic moment, gives a good agreement with the exact numerical evaluation.

  • Asymptotic Photon Propagator in massive QED and the muon anomalous magnetic moment
    Physics Letters B, 1991
    Co-Authors: T. Kinoshita, H. Kawai, Yuko Okamoto
    Abstract:

    Abstract Recently, Faustov et al. have obtained, by a renormalization group technique, the asymptotic contribution to the muon anomalous magnetic moment arising from the eighth-order diagrams containing two electron vacuum-polarization loops, one within the other. Their result disagrees strongly with the value previously obtained by numerical evaluation of exact eighth-order integrals. We have identified the cause of this discrepancy to be an incorrect four-loop Callan-Symanzik β-function. Using the corrected β-function, which takes the effect of finite electron mass into account, we find that the result of Faustov et al. agrees very well with that of numerical integration.

E.-m. Ilgenfritz - One of the best experts on this subject based on the ideXlab platform.

  • Compact Q=2 Abelian Higgs model in the London limit: Vortex-monopole chains and the Photon Propagator
    Physical Review D, 2005
    Co-Authors: M. N. Chernodub, E.-m. Ilgenfritz, R. Feldmann, Arwed Schiller
    Abstract:

    The confining and topological properties of the compact Abelian Higgs model with doubly-charged Higgs field in three space-time dimensions are studied. We consider the London limit of the model. We show that the monopoles are forming chainlike structures (kept together by Abrikosov-Nielsen-Olesen vortices), the presence of which is essential for getting simultaneously permanent confinement of singly-charged particles and breaking of the string spanned between doubly-charged particles. In the confinement phase, the chains are forming percolating clusters, while in the deconfinement (Higgs) phase, the chains are of finite size. The described picture is in close analogy with the synthesis of the Abelian monopole and the center vortex pictures in confining non-Abelian gauge models. The screening properties of the vacuum are studied by means of the Photon Propagator in the Landau gauge.

  • Photon Propagator in compact(2+1)-dimensional QED: The effect of wrapping Dirac strings
    Physical Review D, 2004
    Co-Authors: M. N. Chernodub, E.-m. Ilgenfritz, Arwed Schiller
    Abstract:

    We discuss the influence of closed Dirac strings on the Photon Propagator in the Landau gauge emerging from a study of the compact U(1) gauge model in 2+1 dimensions. This gauge also minimizes the total length of the Dirac strings. Closed Dirac strings are stable against local gauge-fixing algorithms only due to the torus boundary conditions of the lattice. We demonstrate that these left-over Dirac strings are responsible for the previously observed unphysical behavior of the Propagator of space-like Photons (D_T) in the deconfinement (high temperature) phase. We show how one can monitor the number N_3 of thermal Dirac strings which allows to separate the Propagator measurements into N_3 sectors. The Propagator in N_3 \neq 0 sectors is characterized by a non--zero mass and an anomalous dimension similarly to the confinement phase. Both mass squared and anomalous dimension are found to be proportional to N_3. Consequently, in the N_3=0 sector the unphysical behavior of the D_T Photon Propagator is cured and the deviation from the free massless Propagator disappears.

  • More on String Breaking in the 3D Abelian Higgs Model: the Photon Propagator
    Physics Letters B, 2003
    Co-Authors: M. N. Chernodub, E.-m. Ilgenfritz, Arwed Schiller
    Abstract:

    We study the Landau gauge Photon Propagator in the three--dimensional Abelian Higgs model with compact gauge field and fundamentally charged matter in the London limit. The total gauge field is split into singular and regular parts. On the confinement side of the string breaking crossover the momentum dependence of the total Propagator is characterized by an anomalous dimension similarly to 3D compact QED. At the crossover and throughout the Higgs region the anomalous dimension disappears. This result perfectly agrees with recent observations that the monopole--antimonopole plasma leads to nonzero anomalous dimension and the presence of the matter fields causes monopole pairing into dipole bound states. The Yukawa mass characterizing the Propagator part from regular gauge fields is non-vanishing at the Higgs side and coincides with the mass found for the total Propagator. The regular gauge field without anomalous dimension becomes massless at the crossover and in the confinement region.

  • Monopoles, confinement and the Photon Propagator in QED3
    Nuclear Physics B - Proceedings Supplements, 2003
    Co-Authors: M. N. Chernodub, E.-m. Ilgenfritz, Arwed Schiller
    Abstract:

    Abstract We study the lattice gauge boson Propagator of3D compact QED in Landau gauge at zero and non-zero temperature. Non-perturbative effects are reflected by the generation of a massm, by an anomalous dimension α and by the Photon wave function renormalisationZ. These effects can be attributed to monopoles: they are absent in the Propagator of the regular part of the gauge field. The role of Gribov copies is carefully investigated.

  • Confinement, Deconfinement and the Photon Propagator in 3d cQED on the Lattice
    Quark Confinement and the Hadron Spectrum V, 2003
    Co-Authors: M. N. Chernodub, E.-m. Ilgenfritz, Arwed Schiller
    Abstract:

    We report on a lattice study of the gauge boson Propagator of 3D compact QED in Landau gauge at zero and finite temperature. Non-perturbative effects are reflected by the generation of a mass m and by an anomalous dimension alpha. These effects can be attributed to monopoles and are absent in the Propagator of the regular part of the gauge field.

H. Kawai - One of the best experts on this subject based on the ideXlab platform.

  • Asymptotic Photon Propagator and higher-order QED Callan-Symanzik β function
    Physics Letters B, 1991
    Co-Authors: H. Kawai, T. Kinoshita, Yuko Okamoto
    Abstract:

    The QED Callan-Symanzik β function is calculated for a certain class of higher-order Photon self-energy diagrams within the framework of perturbative QED. It is found that the formulation of de Rafael and Rosner is valid up to the sixth order but must be modified from the eighth order on. Correction terms are evaluated explicitly. The result, applied a renormalization group calculation of an eighth-order contribution to the muon anomalous magnetic moment, gives a good agreement with the exact numerical evaluation.

  • Asymptotic Photon Propagator in massive QED and the muon anomalous magnetic moment
    Physics Letters B, 1991
    Co-Authors: T. Kinoshita, H. Kawai, Yuko Okamoto
    Abstract:

    Abstract Recently, Faustov et al. have obtained, by a renormalization group technique, the asymptotic contribution to the muon anomalous magnetic moment arising from the eighth-order diagrams containing two electron vacuum-polarization loops, one within the other. Their result disagrees strongly with the value previously obtained by numerical evaluation of exact eighth-order integrals. We have identified the cause of this discrepancy to be an incorrect four-loop Callan-Symanzik β-function. Using the corrected β-function, which takes the effect of finite electron mass into account, we find that the result of Faustov et al. agrees very well with that of numerical integration.