Subject: Re: two questions Date: Mon, 11 Mar 2002 15:36:37 -0500 (EST) From: Dev Sinha > when the frenet frame of a smoosh closed space curve traces > the curve one turn,endpoint of its normal vector constructs another > curve in space. these two curves have a linking number. > What this linking number means, is there anything about it in > litrature? This number is often called the self-linking number. It is often attributed to Pohl: 36 #5827 Pohl, William F. The self-linking number of a closed space curve. J. Math. Mech. 17 1967/1968 975--985. (Reviewer: L. Neuwirth) 53.01 Searching Mathscinet with keyword "self-linking" thirteen references come up, including a much older article of Blanchfield and Fox. For polygonal curves, a version was defined by Banchoff. Recently, Bott and Taubes and others have included this self-linking number as one of (in fact, the simplest of) the finite-type knot invariants. -Dev