2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/189401We consider the mirage cosmology by an unstable probe brane whose action is represented by BDI action with tachyon. We study how the presence of tachyon affects the evolution of the brane inflation. At the early stage of the brane inflation, the tachyon kinetic term can play an important role in curing the superluminal expansion in mirage cosmology.11 pages, improved presentation with some clarifications, typos corrected, references addedHigh Energy Physics - Theorytext