“…Roughly speaking, it is an invariant that measures how quickly the category can be built from one object. Many authors have studied the upper bound of tri.dim T , see [3,5,7,9,12,14,17,18,22,25,23] and so on. There are a lot of triangulated categories having infinite dimension, for instance, Oppermann and Št'ovíček proved in [14] that all proper thick subcategories of the bounded derived category of finitely generated modules over a Noetherian algebra containing perfect complexes have infinite dimension.…”