Limit theories and continuous orbifolds

Understand

Relativistic QFTs are in general defined by a collection of effective actions, describing the dynamics of quantum fields at different energy scales.

• The consequent natural idea of a space of theories is still a rather imprecise notion, since a detailed knowledge or a classification of QFTs is out of reach.
• In two dimensions the situation is in a better shape: in this context CFTs are under control in many instances, and we know sequences of rational theories emerging as end-points of RG flows.
• The present thesis explores the behaviour of sequences of rational two-dimensional CFTs when the central charge approaches its supremum.