Sökning: "mean field"

Visar resultat 11 - 15 av 556 avhandlingar innehållade orden mean field.

  1. 11. From mean-field hydromagnetics to solar magnetic flux concentrations

    Författare :Koen Kemel; Axel Brandenburg; Alexander Ruzmaikin; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; magneto-hydrodynamics; solar physics; turbulence; Astronomy; astronomi;

    Sammanfattning : The main idea behind the work presented in this thesis is to investigate if it is possible to find a mechanism that leads to surface magnetic field concentrations and could operate under solar conditions without postulating the presence of magnetic flux tubes rising from the bottom of the convection zone, a commonly used yet physically problematic approach.In this context we study the ‘negative effective magnetic pressure effect’: it was pointed out in earlier work (Kleeorin et al. LÄS MER

  3. 12. Investigation of effective interactions in relativistic mean field theory

    Författare :Shufang Ban; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Nuclear physics; Kärnfysik;

    Sammanfattning : .... LÄS MER

  4. 13. Variational Methods in Combinatorial Optimization and Phylogeny Reconstruction

    Författare :Henrik Jönsson; Beräkningsbiologi och biologisk fysik - Genomgår omorganisation; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; statistical physics; gravitation; relativity; annealing; variational; mean-field; phylogeny; constraint satisfaction; combinatorial optimization; maximum likelihood; Physics; Fysik; Mathematical and general theoretical physics; quantum mechanics; classical mechanics; klassisk mekanik; kvantmekanik; relativitet; statistisk fysik; termodynamik; Fysicumarkivet A:2001:Jönsson; Matematisk och allmän teoretisk fysik; thermodynamics;

    Sammanfattning : Algorithms based on the variational approach, as used in statistical physics, are developed. For constraint satisfaction problems a novel cost function, based on information-theoretic arguments, is introduced, and an algorithm similar to the mean-field annealing algorithm is proposed. LÄS MER

  5. 14. Non-Linear Canonical Methods in Strongly Correlated Electron Systems

    Författare :Matteo Bazzanella; Göteborgs universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Majorana fermions; Emergent Majorana fermions; Non-linear transformation; canonical transformation; Kondo lattice; Mott insulator; Mean-field; Path-integral;

    Sammanfattning : In this thesis some new ideas to perform the analysis of Strongly Correlated Electronic Systems (SCES) are developed. In particular the use of non-linear canonical transformations is considered thoroughly. LÄS MER

  7. 15. Fermions in two dimensions and exactly solvable models

    Författare :Jonas de Woul; Edwin Langmann; Fabian Essler; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Bosonization; Exactly solvable models; Hubbard model; Mean field theory; Quantum field theory; Strongly correlated systems;

    Sammanfattning : This Ph.D. thesis in mathematical physics concerns systems of interacting fermions with strong correlations. For these systems the physical properties can only be described in terms of the collective behavior of the fermions. LÄS MER