FB Mathematik und Informatik der FU Berlin:
Es spricht

        Prof. Dr. Gaiane Panina (St. Petersburg)

zum Thema


Zeit: Do., 26.10.06, 17 Uhr c.t.
Ort: Hörsaal Informatik, Takustraße 9, 14195 Berlin

Tee, wie immer, ab 16:45,
jedoch diesmal in Raum 137, FU-Informatik, Takustraße 9, 1. Stock

We show that the following two (quite different!) problems have one and the
same combinatorial background.

1. Carpenter's rule problem.
   Can any carpenter's ruler (a closed planar non-crossing closed
   broken line) be straightened in the plane avoiding self-crossing?
2. A.D. Alexandrov's problem.
   Given a smooth convex 3D-body K and a constant C which separates
   the principal curvature radii of K (i.e. R1 <= C <= R2 everywhere),
   is K necessarily a ball?

The talk is based on papers by R. Connelly,  R. Haas, Y. Martinez-Maure,
D. Orden, G. Rote, F. Santos, B. Servatius, H. Servatius,  I. Streinu,
W. Whiteley, the speaker and others.