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Aug 24, 2012 at 18:07 comment added Will Sawin It's not clear if "related" is even well-defined enough here to give that question a satisfying answer. Which mathematical statements are related to $2+2=2\times 2$?
Aug 24, 2012 at 6:47 history edited Qiaochu Yuan CC BY-SA 3.0
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Aug 24, 2012 at 6:20 history edited Qiaochu Yuan CC BY-SA 3.0
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Aug 24, 2012 at 4:49 comment added Qiaochu Yuan @Will: I had other other reasons in mind (for example the fact that $\Lambda^2(\mathbb{R}^4)$ is not an irreducible representation of $\text{SO}(4)$) but who knows, maybe they're all related.
Aug 24, 2012 at 4:28 comment added Will Sawin Isn't that just dependent on whether $n=\max_{k=0}^n k(n-k)$ - the max of the dimension of the various Grassmanians, since the number of points on an algebraic variety of dimension $d$ goes to $p^d$ as $p\to \infty$ by the Weil conjectures? It doesn't seem plausible to me that there are exotic $\mathbb R^4$s because $\operatorname{Gr}_2^2$ is $4$-dimensional, but I know nothing of the relevant topology and certainly stranger things have happened.
Aug 24, 2012 at 3:44 history edited Qiaochu Yuan CC BY-SA 3.0
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Aug 24, 2012 at 3:30 comment added Qiaochu Yuan Curiously $4$ is the only dimension $d$ in which $R(C_p^d)$ approaches $1$ as $p \to \infty$, and the reason is something happening in the middle dimension. I wonder if this is related to the other reasons that $4$ is an exceptional dimension...
Aug 24, 2012 at 2:04 history undeleted Qiaochu Yuan
Aug 24, 2012 at 2:03 history edited Qiaochu Yuan CC BY-SA 3.0
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Aug 24, 2012 at 1:44 history deleted Qiaochu Yuan
Aug 24, 2012 at 0:36 history answered Qiaochu Yuan CC BY-SA 3.0