Speaker
Loriano Bonora
(TS)
Description
The talk tries to address the question: how to construct a local field
theory with infinite many fields. First the effective action method is
presented. It is shown how it naturally leads to the definition of
(generally non-local) field theories. It has however strong technical
limitations. Then the more powerful and systematic worldline approach is
introduced, which carries the L-infinity symmetry and relevant Ward
indentities. The latter can be integrated, leading to a set of new
theories: YM-like theories in any dimension and CS-like theories in any
odd dimension. The structure the YM-like theories, in particular the
absence of propagating ghosts, is discussed. Finally a possible
connection with string theory is suggested.
