What if phi^4 theory in 4 dimensions is non-trivial in the continuum?

04.11.2025 14:00 - 15:30

Paul Romatschke (TU Wien)

Abstract:
Traditionally, scalar phi^4 theory in four dimensions is thought to be quantum trivial in
the continuum. In this talk, I critically review what quantum triviality is, and in
particular which parts of the idea have actually been mathematically proved as
opposed to just assumed to be true. I go on to exploit loopholes in the mathematical
proofs, notably multi-component fields, to present a concrete calculation that avoids
quantum triviality in scalar phi4 theory in the continuum. There is a price to pay to
avoid triviality, but there are also potentially rich rewards. Your mileage will vary.
Whatever the outcome, it is great fun to work on this subject!

Organiser:
S. Fredenhagen, M. Sperling
Location:

Fakultät für Physik, Erwin Schrödinger-Hörsaal, Boltzmanng. 5, 5. St., 1090 Wien