Sökning: "K-theory"

Visar resultat 1 - 5 av 9 avhandlingar innehållade ordet K-theory.

  1. 1. Group Extensions, Gerbes and Twisted K-theory

    Författare :Pedram Hekmati; Jouko Mickelsson; Jürgen Fuchs; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Mathematical physics; Matematisk fysik;

    Sammanfattning : This thesis reviews the theory of group extensions, gerbes and twisted K-theory. Application to anomalies in gauge theory is briefly discussed. The main results are presented in two appended scientific papers. LÄS MER

  3. 2. N-complexes and Categorification

    Författare :Djalal Mirmohades; Volodymyr Mazorchuk; Steffen Oppermann; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Homological algebra; Category theory; Triangulated categories; K-theory; Hopfological algebra; Mathematics; Matematik;

    Sammanfattning : This thesis consists of three papers about N-complexes and their uses in categorification. N-complexes are generalizations of chain complexes having a differential d satisfying dN = 0 rather than d2 = 0. Categorification is the process of finding a higher category analog of a given mathematical structure. LÄS MER

  4. 3. Abelian Extensions, Fractional Loop Group and Quantum Fields

    Författare :Pedram Hekmati; Jouko Mickelsson; Christoph Schweigert; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Lie group extensions; Lie conformal algebras; gerbes; twisted K-theory; renormalization; anomalies; D-brane charges; variational complex; Mathematical physics; Matematisk fysik;

    Sammanfattning : This thesis deals with the theory of Lie group extensions, Lie conformal algebras and twisted K-theory, in the context of quantum physics. These structures allow for a mathematically precise description of certain aspects of interacting quantum field theories. LÄS MER

  5. 4. A descent principle for compact support extensions of functors

    Författare :Josefien Kuijper; Dan Petersen; Tom Bachmann; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; matematik; Mathematics;

    Sammanfattning : This licentiate thesis consists of one paper about cohomology theories of algebraic varieties. Certain cohomology theories, such as singular cohomology of topological spaces, and sheaf cohomology, have a variant that we call “compactly supported cohomology”. LÄS MER

  7. 5. Topological Phases of Non-Hermitian physics

    Författare :Lukas Rødland; Maria Hermanns; Jorge Cayao; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Theoretical Physics; teoretisk fysik;

    Sammanfattning : Non-Hermitian physics has introduced phenomena like the skin effect and exceptional points, challenging traditional views of topological phases. This thesis contrasts two classification frameworks for non-Hermitian systems. LÄS MER