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What is the largest subset of the sphere such that inner product of any two points nin the set is nonnegative

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What is the largest subset of the sphere such that inner product of any two points n the set is nonnegative

I'm interested in the question of finding the maximum area of $A\subset S^{d-1}$, such that, for all $x,y \in A, \left<x,y\right>\ge 0$. The portion of the sphere lying in the positive orthant seems like a reasonable guess. Can any subset of the sphere that satisfies the positive inner product property be rotated to fit in the positive orthant? I seem to have some evidence that the answer to this last question is "no" but I would like to know for certain.