Timeline for Is it known that $(F_p^{\times} \ltimes F_p, F_p)$ is not a relative expander family?

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when toggle format	what		by	license	comment
Mar 20, 2012 at 11:56	comment	added	Freddie Manners		Well, maybe "distance at most 100^100" or so.
Mar 20, 2012 at 11:49	comment	added	Freddie Manners		So, this nicely encapsulates my approach in special cases. E.g. if our generators are $x \mapsto x + 1$ and $x \mapsto 2 x$, you can say something like "take a bunch of elements in $F_p$ with the same low bits when written in base 2", since it still vaguely makes sense to talk about elements of $F_p$ in base 2; but this fails if you switch 2 for $a \approx p^{1/10}$. So, the generalization here is "take elements of $F_p$ which have distance at most 100 from 0 on the edges: $x \mapsto x + a^r$, for $0 \leq r < 100$" which -- in hindsight -- is clearly the correct generalization.
Mar 20, 2012 at 11:44	comment	added	Freddie Manners		Thanks! Putting that together with your blog post, I think "set of all group elements $t \in K$" should read ".. $t \in H$" in para 3, proof of Proposition 5.
Mar 20, 2012 at 11:16	vote	accept	Freddie Manners
Mar 20, 2012 at 0:40	history	edited	Terry Tao	CC BY-SA 3.0	deleted 24 characters in body; added 3 characters in body
Mar 20, 2012 at 0:35	history	answered	Terry Tao	CC BY-SA 3.0