Sökning: "invariant theory"
Visar resultat 1 - 5 av 139 avhandlingar innehållade orden invariant theory.
1. Homotopy Theory and TDA with a View Towards Category Theory
Sammanfattning : This thesis contains three papers. Paper A and Paper B deal with homotopy theory and Paper C deals with Topological Data Analysis. All three papers are written from a categorical point of view.In Paper A we construct categories of short hammocks and show that their weak homotopy type is that of mapping spaces. LÄS MER
2. Yang-Mills Theory in Gauge-Invariant Variables and Geometric Formulation of Quantum Field Theories
Sammanfattning : In Part I we are dealing with effective description of Yang-Mills theories based on gauge-invarint variables. For pure Yang-Mills we study the spin-charge separation varibles. The dynamics in these variables resembles the Skyrme-Faddeev model. LÄS MER
3. Strings, Conformal Field Theory and Noncommutative Geometry
Sammanfattning : This thesis describes some aspects of noncommutative geometry and conformal field theory. The motivation for the investigations made comes to a large extent from string theory. This theory is today considered to be the most promising way to find a solution to the problem of unifying the four fundamental interactions in one single theory. LÄS MER
4. Defects, renormalization and conformal field theory
Sammanfattning : Defects in quantum field theories appear in many different contexts and are of great physical interest. Among other things, defects are used to describe the Kondō effect in condensed matter, confinement in quantum chromodynamics, Rényi entropy in quantum information and cosmic strings in string theory. LÄS MER
5. On Rank-invariant Methods for Ordinal Data
Sammanfattning : Data from rating scale assessments have rank-invariant properties only, which means that the data represent an ordering, but lack of standardized magnitude, inter-categorical distances, and linearity. Even though the judgments often are coded by natural numbers they are not really metric. LÄS MER