We prove a transference principle that says that certain optimization problems for functions on the circle, the interval, and the line have the same answers. In particular, we show that the sharp constants in the John–Nirenberg inequalities for naturally defined BMO-spaces on the circle, the interval, and the line coincide. The same principle holds true for the Reverse Hölder inequality for Muckenhoupt weights.

中文翻译：

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BMO和A _p的急剧转移原则

我们证明了转移原理，该原理说圆，区间和直线上的函数的某些优化问题具有相同的答案。特别是，我们证明了圆，间隔和直线上自然定义的BMO空间的John–Nirenberg不等式中的尖锐常数一致。相同的原理适用于Muckenhoupt权重的反向Hölder不等式。