Optimal Partial Regularity for Nonlinear Sub-elliptic Systems Related to Hörmander’s Vector Fields
نویسندگان
چکیده
This paper is concerned with partial regularity for weak solutions to nonlinear sub-elliptic systems related to Hörmander’s vector fields. The method of A-harmonic approximation introduced by Simon and developed by Duzaar and Grotowski is adapted to our context, and then a Caccioppoli-type inequality and partial regularity with optimal local Hölder exponent for gradients of weak solutions to the systems under super-quadratic natural growth conditions is established.
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