When we impose the constraints of causality and stability, the inverse system is unique; and the system \ mathbb { H } and its inverse \ mathbb { H } _ { inv } are called "'minimum-phase " '.
12.
More generally, if " F " is an inverse system of �tale sheaves " F i ", then the cohomology of " F " is defined to be the inverse limit of the cohomology of the sheaves " F i"
13.
In the special case where all " n " " i " have the same value " n ", so that the inverse system is determined by the multiplication by " n " self map of the circle, solenoids were first introduced by hyperbolic dynamical systems.
