Math Twitter: How many almost-orthogonal unit vectors can you fit into n dimensions? Is there a good bound to help get a sense for this?
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@dabacon,@AndrewDohertyQu, what are good results on this? Tyler: for fixed epsilon, you can find exponentially many unit vectors such that the inner product between each is < epsilon. IIRC, it's pretty easy to prove by choosing vectors at random, & weeding out exceptions.
I believe there are explicit constructions based on error-correcting codes, too.
