2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/43734In this talk, I describe a few interesting physics beyond the standard model that are quite unique for $γγ$ collisions, including large extra dimension model (ADD), warped extra dimension model (Randall-Sundrum) model, universal extra dimension model, as well as techni-pions of technicolor models.4 pages and 4 figures. Parallel talk given at Gamma Gamma session in the International Conference on Linear Colliders, LCWS04, 19-23 April 2004, Paris, FranceHigh Energy Physics - Phenomenologytext