Electroweak effective lagrangians

In this paper I review several aspects of the use of effective lagrangians in (mainly) electroweak physics. The conditions under which this approach is reliable and useful, as well as the limitations of the formalism are detailed. Various applications are also presented.Comment: 89 page

A short course in effective Lagrangians

These lectures provide an introduction to effective theories concentrating on the basic ideas and providing some simple applicationsComment: Lectures delivered at the VII Mexican Workshop on Particles and Fields, Merida, Yucatan, Mexico, 10-17 November, 1999. 29 pages, 8 figure

Effective operator contributions to the oblique parameters

We present a model and process independent study of the contributions from non-Standard Model physics to the oblique parameters S, T and U. We show that within an effective lagrangian parameterization the expressions for the oblique parameters in terms of observables are consistent, while those in terms of the vector-boson vacuum polarization tensors are ambiguous. We obtain the constraints on the scale of new physics derived from current data on S, T and U and note that deviations in U from its Standard Model value would favor a scenario where the underlying physics does not decouple.Comment: 13 pages, RevTe