Theory of Gauge Boson Structure

I have been asked to review the theory of vector boson structure. Recent discussion about the possibility of composite vectors and the meaning of structure has been rather confusing, but I believe a consensus is beginning to emerge. Because the following talk by Dr. Miyamoto will review in some detail the phenomenological possibilities, I will concentrate on the theoretical underpinnings. In the context of the Next Linear Collider, I would say the main goal is to understand the extent to which studies of vector boson couplings can provide insights into new, unknown physics beyond the Standard Model, given the sensitivities that are likely to be achievable. The outline of my talk is as follows: In the next section, in order to introduce my nomenclature and to highlight the issues in a simpler context, I begin by considering the analogous situation for QED. In Section 3, I will generalize to the present-day situation. In Section 4, I review the now-standard parameterization of deviations of the triple-vector-boson couplings from the SM. In Section 5, I will expand on the case of the strongly interacting Higgs sector. In Section 6, I discuss the orders of magnitude to be expected on general theoretical grounds. In Section 7, I will try to indicate why gauge invariance is such a critical issue and why it would be so difficult to understand the present successes of the SM without it.†