Suspension is a construction passing from a map to a flow. Namely, let be a metric space, be a continuous map and be a function (roof function or ceiling function) bounded away from 0. Consider the quotient space
The suspension of with roof function is the semiflow induced by the time translation .
If , then the quotient space is also called the mapping torus of .
- ^ M. Brin and G. Stuck, Introduction to Dynamical Systems, Cambridge University Press, 2002.