From linear SUSY to constrained superfields

by Nathan Seiberg (IAS)

Wednesday 9 Sept 2009, 14:00 → 15:00 Europe/Zurich

TH Theory Conference Room (CERN)

We present a new formalism for finding the low-energy effective Lagrangian of Goldstinos (light gravitinos) and other fields. This Lagrangian is written using standard superspace and the superfields are constrained to include only the light degrees of freedom. The Goldstino resides in a (constrained) chiral superfield X which is naturally identified at short distances. This allows us to exactly compute the IR behavior of some correlation functions even in strongly coupled theories with SUSY breaking. The Goldstino couplings above the scale of the matter superpartners are determined by identifying X with the standard spurion. At energies below the superpartners' scale, fermions, scalars (including Goldstone bosons) and gauge fields are also described by constrained superfields. Our framework makes it easy to find the leading order terms in the Lagrangian and to control their corrections. It simplifies the derivation of many known results and leads to new ones.

Slides Seiberg.pdf Seiberg.ppt