Non-differentiability of alpha function at the boundary of flat

Authors
Zhang, Jian Lu Zhou, Min
Citation
Zhang, Jian Lu et Zhou, Min, Non-differentiability of alpha function at the boundary of flat, Acta mathematica Sinica. English series (Print) , 30(8), 2014, pp. 1341-1352
Journal title
Acta mathematica Sinica. English series (Print) → ACNP
ISSN journal
14398516
Volume
30
Issue
8
Year of publication
2014
Pages
1341 - 1352
Database
ACNP
SICI code
Abstract
With the variational method introduced by Mather, we construct a mechanical Hamiltonian system whose . function has a flat {ie1341-1} and is non-differentiable at the boundary {ie1341-2}. In the case of two degrees of freedom, we prove that this phenomenon is stable under perturbations of Mañé.s.