I am reading R.E.Gompf and A.I. Stipsicz, 4-Manifolds and Kirby Calculus.At pp.100-101,the authors say "isotopy classes of framings."I don't know how to determine isotopy to framings.Please tell me about this.
What's isotopy of framings?
0
$\begingroup$
geometry
algebraic-geometry
differential-geometry
low-dimensional-topology