lets imagine building up a tiling S step by step (for concreteness in say, a square grid we can enumerate the squares in a spiral around the origin and say at each stage we're adding a tile to cover the uncovered square with the smallest number, so we reach everywhere eventually)
for any tilings of the plane T,S we write T->S if every finite patch of tiles in S occurs infinitely often in T.
(1) we first show that if T->T either T is periodic or there are uncountably many tilings
ok here's a more concrete + human understandable proof of uncountability
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RT @pawnofcthulhu
cute
one quote "the tile admits uncountably many tilings": is it even possible to have a set of tiles that aperiodically tile the plane without having uncountably many tilings? https://twitter.com/cs_kaplan/status/1637996332475359232
https://twitter.com/pawnofcthulhu/status/1638004102352498688
https://twitter.com/CihanPostsThms/status/1644700418583273473
here's a result you get with very similar argument lol
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RT @CihanPostsThms
The following is a theorem of ZFC (in particular CH is not assumed):
Let G be a group of cardinality ≤ |ℕ|. Then the cardinality of the set of subgroups of G is
• either ≤ |ℕ|,
• or equal to |ℝ|.
https://twitter.com/CihanPostsThms/status/1644700418583273473
this is decidedly less awkward if you don't sell the indigenous people guns and horses and let them fight it out for a century or two before you move in
it does tend to get annoying when contextualising norms are so strong they don't let you say anything more complicated than 'red team good blue team bad' tho
of course for a viewpoint like this there are going to be people you can't persuade and who are going to be angry at you either way
(in case you couldn't guess the half dozen dots off the main sequence are very remote/outback areas with high indigenous population)
sorry i had to scale the dots by population, can't have you thinking we're *too* poor; resolution is not great but they range from like 40k to 800k
sorry i had to scale the dots by population, can't have you thinking we're *too* poor; they range from like 40k to 800k
tried to plot this for australia and this sure tells a story huh
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RT @jburnmurdoch
2) It’s actually worse than that chart made out, because at most points on the income distribution, Americans earn much more than Brits.
If we plot the same data by actual income instead of percentile, the US deficit is vast.
5 fewer years even among the comfortably-off. https://t.co/ssffHKqbLv
https://twitter.com/jburnmurdoch/status/1641799667942866944
queering the randos in my dms asking for nudes/ randos in my dms asking for math advice binary
twitter: pawnofcthulhu