Gradients and canonical transformations
Annales Polonici Mathematici, Tome 72 (1999) no. 2, pp. 153-158
Voir la notice de l'article provenant de la source Institute of Mathematics Polish Academy of Sciences
The main aim of this paper is to give some counterexamples to global invertibility of local diffeomorphisms which are interesting in mechanics. The first is a locally strictly convex function whose gradient is non-injective. The interest in this function is related to the Legendre transform. Then I show two non-injective canonical local diffeomorphisms which are rational: the first is very simple and related to the complex cube, the second is defined on the whole ℝ⁴ and is obtained from a recent important example by Pinchuk. Finally, a canonical transformation which is also a gradient (of a convex function) is provided.
Mots-clés :
non-injective local diffeomorphisms, gradients, Legendre transform, canonical transformations
Affiliations des auteurs :
Gaetano Zampieri 1
@article{10_4064_ap_72_2_153_158,
author = {Gaetano Zampieri},
title = {Gradients and canonical transformations},
journal = {Annales Polonici Mathematici},
pages = {153--158},
publisher = {mathdoc},
volume = {72},
number = {2},
year = {1999},
doi = {10.4064/ap-72-2-153-158},
language = {fr},
url = {http://geodesic.mathdoc.fr/articles/10.4064/ap-72-2-153-158/}
}
TY - JOUR AU - Gaetano Zampieri TI - Gradients and canonical transformations JO - Annales Polonici Mathematici PY - 1999 SP - 153 EP - 158 VL - 72 IS - 2 PB - mathdoc UR - http://geodesic.mathdoc.fr/articles/10.4064/ap-72-2-153-158/ DO - 10.4064/ap-72-2-153-158 LA - fr ID - 10_4064_ap_72_2_153_158 ER -
Gaetano Zampieri. Gradients and canonical transformations. Annales Polonici Mathematici, Tome 72 (1999) no. 2, pp. 153-158. doi: 10.4064/ap-72-2-153-158
Cité par Sources :