Stabilizations of $s$-cobordisms of dimension $5$

It has long been known that the $s$-cobordism theorem fails for $5$-dimensional $s$-cobordisms. In this article we study how many times of "stabilizations" are needed to turn a $5$-dimensional $s$-cobordism to a product cobordism. The question is analogous to asking how many times of stabilizations are needed to turn an exotic pair of four manifolds into diffeomorphic ones. The main tools in this article are Gabai's $4$D light bulb theorem and its applications, and we also use a refinement of $4$D light bulb theorem by Freedman Quinn invariant.