In this paper, by using the theory of integral bordism groups in PDE's, previously introduced by Prastaro, we give a new interpretation of the concept of (un)stability in the framework of the geometric theory of PDE's. A geometric criterium to identify stable PDE's and stable solutions of PDE's is given.
Banach J. Math. Anal.
1(1):
139-147
(2007).
DOI: 10.15352/bjma/1240321564
