Given a compact connected Lie group $ G $, we estimated the constant for the Sobolev inequality for an arbitrary Hörmander sub-Laplacian on $ G $. The constant was estimated in terms of quantities depending on the intrinsic geometry of the group and on the Lebesgue parameters. We also provided applications of this result to the estimation of the operator norm for $ L^p $-$ L^q $-bounded subelliptic pseudo-differential operators in subelliptic Hörmander classes.
Citation: Andrea V. Hurtado-Quiceno, Duván Cardona Sánchez. The constant in the Sobolev inequality and the boundedness of subelliptic operators on compact Lie groups[J]. Communications in Analysis and Mechanics, 2025, 17(4): 878-897. doi: 10.3934/cam.2025035
Given a compact connected Lie group $ G $, we estimated the constant for the Sobolev inequality for an arbitrary Hörmander sub-Laplacian on $ G $. The constant was estimated in terms of quantities depending on the intrinsic geometry of the group and on the Lebesgue parameters. We also provided applications of this result to the estimation of the operator norm for $ L^p $-$ L^q $-bounded subelliptic pseudo-differential operators in subelliptic Hörmander classes.
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