| Résume | In this talk, we will present hedgehogs of constant width and Zindler curves, as
well as their relationship, in non-Euclidean geometries.
First, we will recall how support functions constitute a very useful tool to prove
some classical results. Following the same ideas, the notions of a hedgehog, a
Zindler curve and a width can be extended to elliptic and hyperbolic planes, as
well as different possibilities of defining a support function. In particular, two
notions of hedgehogs in the hyperbolic plane will be possible, namely g-
hedgehogs and h-hedgehogs, which generalize the well-known notions of g-
convex and h-convex curves. |
