The sharp constants in the real anisotropic Littlewood's $4/3$ inequality and applications

Nicolás Caro-Montoya, Daniel Núñez-Alarcón, Diana Serrano-Rodríguez

The real anisotropic Littlewood's $4/3$ inequality is an extension of a famous result obtained in 1930 by J. E. Littlewood. It asserts that, for $a,b\in (0,\infty )$, the f…