טכניון מכון טכנולוגי לישראל
הטכניון מכון טכנולוגי לישראל - בית הספר ללימודי מוסמכים  
Ph.D Thesis
Ph.D StudentShaverin Evgeny
SubjectQuantum Anomalies in Thermal Field Theories
DepartmentDepartment of Physics
Supervisor Professor Amos Yarom
Full Thesis textFull thesis text - English Version


Abstract

The present work focuses on the study of quantum anomalies. The term `quantum anomalies' refers to a phenomenon in which the conservation laws of a classical theory are being violated upon the quantization. In this work we address two independent areas in the study of quantum anomalies ? the applications of anomalies to physical systems, and theoretical study of anomalies on manifolds with boundaries.


In the first study, we investigate the effect of quantum anomalies on the physics of neutron stars. Since the discovery of neutron stars, it has been observed that they can move through space with very high velocities with typical values of about 500 km/s. Currently, the scientific community lacks consensus regarding the causal explanation for such velocities. Employing and rederiving the methods developed in previous studies, we build a model for the propulsion mechanism, which is based on asymmetric neutrino emission from a neutron star. We find that in the presence of a sufficiently high magnetic fields, our model provides a reasonable estimate of the observed velocities.


In the second study, we examine a theoretical aspect of anomalies ? the possibility of placing theories with anomalies on manifolds with a boundary. Since the discovery of quantum anomalies in late sixties of the last century, most of the research was done for theories defined on manifolds without boundaries. Much less is known regarding theories with anomalies on manifolds with boundaries. Assuming locality, we prove in this work that there is an obstruction to placing theories with anomalies on manifolds with a boundary, unless the symmetry group associated with an anomaly is Abelian.