Effective Field Theory for Spontaneously Broken Symmetry
Tomáš Brauner
Abstract
Symmetry has accompanied our attempts to understand the inner workings of nature ever since the birth of science. The powerful concept of spontaneous symmetry breaking (SSB) makes it possible to reconcile the complex experimental phenomenology with the simplicity of underlying natural laws. It is therefore a necessary ingredient of virtually any textbook on quantum field theory. However, a typical textbook-level treatment offers a mere simplified version of the state of the art of the subject in its early days of the 1960s. This hardly does justice to the richness and beauty of SSB. Moreover, the subject has undergone development in the last two decades that has substantially sharpened our understanding of SSB in quantum many-body systems.