Some theorems on austere submanifolds.
The spread of the shape operator as conformal invariant.
A metric induced by the geometric interpretation of Rolle's theorem.
A projective characterization of cyclicity.
Barbilian's metrization procedure in the plane yields either Riemannian or Lagrange generalized metrics
In the present paper we answer two questions raised by Barbilian in 1960. First, we study how far can the hypothesis of Barbilian's metrization procedure can be relaxed. Then, we prove that Barbilian's metrization procedure in the plane generates either Riemannian metrics or Lagrance generalized metrics not reducible to Finslerian or Langrangian metrics.
Page 1