The rigidity of totally nondegenerate model CR manifolds
arXiv:1702.03213
Abstract
In this paper, we prove that every real analytic totally nondegenerate model CR manifold of length >= 3 has rigidity. This result was actually conjectured before by Valerii Beloshapka as the so-called "maximum conjecture". It follows that the transformation Lie group of all CR automorphisms associated with each of the mentioned models does not include any nonlinear map.
Observing some problems in some certain part of the paper