Orlicz spaces and endpoint Sobolev-Poincaré inequalities for differential forms in Heisenberg groups

  • Annalisa Baldi University of Bologna, Italy
  • Bruno Franchi University of Bologna, Italy
  • Pierre Pansu Université Paris-Sud, CNRS and Université Paris-Saclay, France


In this paper we prove Poincar´e and Sobolev inequalities for differential forms in the Rumin’s contact complex on Heisenberg groups. In particular, we deal with endpoint values of the exponents, obtaining finally estimates akin to exponential Trudinger inequalities for scalar function. These results complete previous results obtained by the authors away from the exponential case. From the geometric point of view, Poincaré and Sobolev inequalities for differential forms provide a quantitative formulation of the vanishing of the cohomology. They have also applications to regularity issues for partial differential equations.