High energy limits of various actions

TL;DR

This thesis explores methods for deriving tensionless limits of strings and similar models, analyzing their applicability through detailed calculations and studying constrained Hamiltonian systems.

Contribution

It introduces and compares two methods for tensionless limits, applying them to various models and examining constrained Hamiltonian systems.

Findings

Methods effectively derive tensionless limits in multiple models

Explicit calculations demonstrate the methods' applicability

Insights into constrained Hamiltonian systems are provided

Abstract

This is a thesis submitted for the cand.scient. degree at the University of Oslo. It is meant to give a thorough presentation of two methods for deriving tensionless limits of strings, and the analogue in other models. Also, the applicability of these methods are investigated by explicitly going through the calculations for a variety of models. An important part of the thesis is the study of constrained Hamiltonian systems.