Lu, Guozhen Weighted Poincaré and Sobolev inequalities for vector fields satisfying Hörmander’s condition and applications. (English) Zbl 0804.35015 Rev. Mat. Iberoam. 8, No. 3, 367-439 (1992). Summary: We prove weighted Poincaré inequalities for vector fields satisfying Hörmander’s condition. A crucial part here is that we are able to get a pointwise estimate for any function over any metric ball controlled by a fractional integral of certain maximal function. The Sobolev type inequalities are also derived. As applications of these weighted inequalities, we show the local regularity of weak solutions for certain classes of strongly degenerate differential operators formed by vector fields. Cited in 79 Documents MSC: 35B45 A priori estimates in context of PDEs 35D10 Regularity of generalized solutions of PDE (MSC2000) 35J70 Degenerate elliptic equations Keywords:weighted Poincaré inequalities; Hörmander’s condition; Sobolev type inequalities; degenerate differential operators PDF BibTeX XML Cite \textit{G. Lu}, Rev. Mat. Iberoam. 8, No. 3, 367--439 (1992; Zbl 0804.35015) Full Text: DOI EuDML