Open questions in quarkonium and electromagnetic probes

Abstract

In my ("not a summary") talk at the Hard Probes 2006 conference, I gave "a personal and surely biased view on only a few of the many open questions on quarkonium and electromagnetic probes". Some of the points reported in that talk are exposed in this paper, having in mind the most important of all the open questions: do we have, today, from experimental data on electromagnetic probes and quarkonium production, convincing evidence that shows, beyond reasonable doubt, the existence of "new physics" in high-energy heavy-ion collisions?Comment: Invited talk at the 2nd Int. Conf. on Hard and EM Probes of High-Energy Nuclear Collisions, Asilomar, California, June 9--16, 2006. To be published in Nuclear Physics A. Late submission to the arXi