Sökning: "renormalization group"

Visar resultat 6 - 10 av 35 avhandlingar innehållade orden renormalization group.

  1. 6. Numerical Renormalization, Doped Antiferromagnets, and Statistics - Topics in Low Dimensional Physics

    Författare :Martin Andersson; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Josephson junctions; matrix-product states; fictitious flux; phase-separation; renormalization; stripes; t-J model; anyons; DMRG;

    Sammanfattning : The first part of the thesis deals with so called numerical renormalization group methods, and in particular the density-matrix renormalization group (DMRG). This method performs extremely well for large one-dimensional quantum systems like spin-chains and Hubbard models. LÄS MER

  3. 7. Strongly Correlated Models in One Dimension from a Density Matrix Renormalization Group Perspective

    Författare :Stefan Rommer; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; matrix product states; impurities; density matrix renormalization group; Heisenberg model; spin chain; DMRG;

    Sammanfattning : The density matrix renormalization group (DMRG) is a numerical method for studying low dimensional strongly correlated models. The study of these models is one of the most active areas of condensed matter physics today and has been spurred not only by the discovery of high temperature superconductivity but also by experiments on new compounds. LÄS MER

  4. 8. Predictions of Effective Models in Neutrino Physics

    Författare :Johannes Bergström; Tommy Ohlsson; Rikard Enberg; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Neutrino mass; lepton mixing; Majorana neutrinos; effective field theory; Weinberg operator; seesaw models; low-scale seesaw models; inverse seesaw; right-handed neutrinos; renormalization group; threshold effects; neutrinoless double beta decay; Elementary particle physics; Elementarpartikelfysik;

    Sammanfattning : Experiments on neutrino oscillations have confirmed that neutrinos have small, but non-zero masses, and that the interacting neutrino states do not have definite masses, but are mixtures of such states.The seesaw models make up a group of popular models describing the small neutrino masses and the corresponding mixing. LÄS MER

  5. 9. Interactions on the edge of a quantum spin Hall insulator

    Författare :Anders Ström; Göteborgs universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; topological insulators; quantum spin Hall effect; low-dimensional physics; bosonization; renormalization group;

    Sammanfattning : Effects from electron-electron interactions on the edge of a quantum spin Hall insulator are studied using bosonisation and renormalisation group methods. First, a quantum spin Hall device with a point contact connecting two of its edges is considered. LÄS MER

  7. 10. Models in Neutrino Physics : Numerical and Statistical Studies

    Författare :Johannes Bergström; Tommy Ohlsson; Pilar Hernandez; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Neutrino mass; lepton mixing; Majorana neutrinos; neutrino oscillations; neutrinoless double beta decay; statistical methods; Bayesian inference; model selection; effective field theory; Weinberg operator; seesaw models; inverse seesaw; right-handed neutrinos; renormalization group; threshold effects.; Neutrinomassor; leptonblandning; Majorananeutriner; neutrinooscillationer; neutrinol¨ost dubbelt betas¨onderfall; statistiska metoder; Bayesisk inferens; modellval; effektiv f¨altteori; Weinbergoperator; seesawmodeller; invers seesaw; högerhänta neutriner; renormeringsgrupp; tröskeleffekter.;

    Sammanfattning : The standard model of particle physics can excellently describe the vast majorityof data of particle physics experiments. However, in its simplest form, it cannot account for the fact that the neutrinos are massive particles and lepton flavorsmixed, as required by the observation of neutrino oscillations. LÄS MER