Unit:
Κατεύθυνση Πυρηνική Φυσική και Φυσική Στοιχειωδών ΣωματιδίωνLibrary of the School of Science
Supervisors info:
Φώτιος Διάκονος, Αναπληρωτής Καθηγητής, Τμήμα Φυσικής, Σχολή Θετικών Επιστημών
Original Title:
Multiple-Scale perturbative method and its application in cosmological perturbations
Translated title:
Multiple-Scale perturbative method and its application in cosmological perturbations
Summary:
The failure to recognize the dependence on more than one time/space scales is a common source of nonuniformity in perturbation expansions. In this thesis perturbative Multiple-Scale method is presented as a tool for global asymptotic analysis. Various multiple-scale techniques are presented. The physical interpretation is discussed. Namely, we provide arguments on the relation between the breaking of Lorentz symmetry and scale-dependent instabilities. Furthermore we discuss the meaning of the quantum mechanical cut-off scale in a semiclassical perturbative treatment. The perturbative Multiple Scale method is attempted in the context of the Effective Field Theory of Inflation. Specifically, we examine its application on the alleviation of the Strong Coupling problem.
Main subject category:
Science
Keywords:
Perturbation Methods, Cosmology, Multiple scales, Cosmological perturbations, Field Theory, Effective Field Theory of Inflation
