2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/190700We review the concept of S-branes introduced by Gutperle and Strominger hep-th/0202210. Using the effective spacetime description of the rolling tachyon worldsheets discussed by Sen, we analyze the possibility that the gravitational backreaction of tachyon matter is important in the time-dependent process. We show that this is indeed the case in the example of the S0-brane in 4-dimensional Einstein-Maxwell theory. This talk is based on hep-th/0207235.8 pages, Talk given at 35th Symposium Ahrenshoop, Contribution to the ProceedingsHigh Energy Physics - TheoryThe Tachyon does Mattertext