𝔖 Bobbio Scriptorium
✦   LIBER   ✦

Rotation numbers for curves on a torus

✍ Scribed by Hitoe Tanio; Osamu Kobayashi


Book ID
104642804
Publisher
Springer
Year
1996
Tongue
English
Weight
454 KB
Volume
61
Category
Article
ISSN
0046-5755

No coin nor oath required. For personal study only.

✦ Synopsis


We define a regular homotopy invariant of closed curves on a surface, and give a formula for the rotation number of closed curves on toms, which is analogous to the Whitney formula for planar curves. As an application, we show a necessary condition for a Gauss word to be realized on toms.


πŸ“œ SIMILAR VOLUMES


Algebraic curves on a torus
✍ O Bottema; E.J.F Primrose πŸ“‚ Article πŸ“… 1974 πŸ› Elsevier Science βš– 304 KB
Rotation curves for 135 edge-on galaxies
✍ D. I. Makarov; A. N. Burenkov; N. V. Tyurina πŸ“‚ Article πŸ“… 2001 πŸ› Springer 🌐 English βš– 60 KB
Graphs on the Torus and Geometry of Numb
✍ A. Schrijver πŸ“‚ Article πŸ“… 1993 πŸ› Elsevier Science 🌐 English βš– 424 KB

We show that if \(G\) is a graph embedded on the torus \(S\) and each nonnullhomotopic closed curve on \(S\) intersects \(G\) at least \(r\) times, then \(G\) contains at least \(\left\lfloor\frac{3}{4} r\right\rfloor\) pairwise disjoint nonnullhomotopic circuits. The factor \(\frac{3}{4}\) is best