The optimal constant in the $L^2$ Folland-Stein inequality on the quaternionic Heisenberg group

Ivanov, Stefan; Minchev, Ivan; Vassilev, Dimiter

Annali della Scuola Normale Superiore di Pisa - Classe di Scienze, Série 5, Tome 11 (2012) no. 3, pp. 635-652.

We determine the best (optimal) constant in the $L^2$ Folland-Stein inequality on the quaternionic Heisenberg group and the non-negative functions for which equality holds.

Classification : 58G30, 53C17

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