A derivation of the sharp Moser-Trudinger-Onofri inequalities from the fractional Sobolev inequalities

Jingang Xiong

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arXiv · 1804.02807

A derivation of the sharp Moser-Trudinger-Onofri inequalities from the fractional Sobolev inequalities

Jingang Xiong

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Abstract

We derive the sharp Moser-Trudinger-Onofri inequalities on the standard $n$-sphere and CR $(2n+1)$- sphere as the limit of the sharp fractional Sobolev inequalities for all $n\ge 1$. On the $2$-sphere and $4$-sphere, this was established recently by S.-Y. Chang and F. Wang. Our proof uses an alternative and elementary argument.

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Jingang Xiong. 2018-04-09. A derivation of the sharp Moser-Trudinger-Onofri inequalities from the fractional Sobolev inequalities. https://arxiv.org/abs/1804.02807

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