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Apr 13, 2017 at 12:58 history edited CommunityBot
replaced http://mathoverflow.net/ with https://mathoverflow.net/
Jul 1, 2015 at 11:28 answer added François G. Dorais timeline score: 12
Jul 1, 2015 at 6:34 comment added David Roberts @hobbs yes, that's it
Jul 1, 2015 at 6:18 comment added hobbs Casual reader here — PA is Peano arithmetic in this context?
Jun 30, 2015 at 21:21 comment added Timothy Chow @QiaochuYuan : Friedman's claim refers to the consistency of first-order PA.
Jun 30, 2015 at 15:20 answer added Timothy Chow timeline score: 15
Jun 30, 2015 at 15:01 history edited Timothy Chow CC BY-SA 3.0
Corrected spelling and added link
Jun 30, 2015 at 8:40 comment added David Roberts Sorry, @QiaochuYuan, forgot to mention you by name, to give you a notification, in the previous comment.
Jun 30, 2015 at 7:13 comment added David Roberts I would imagine first-order PA, although B-W is said to be equivalent to $ACA_0$ over $RCA_0$, and PA is the first-order fragment of $ACA_0$. So maybe B-W is not quite exactly equivalent to $Con(PA)$, but certainly implies it. I wish Friedman would write down his claim properly, so people have something to cite other than 'HF said this on fom, and we all know it to be true anyway...' Restricting to rational sequences in [0,1] probably is a little nicer than full B-W, but I don't know if it really helps.
Jun 30, 2015 at 3:57 comment added Qiaochu Yuan Does Harvey Friedman's claim refer to the consistency of first-order PA or of second-order PA?
Jun 30, 2015 at 2:04 vote accept David Roberts
Jun 30, 2015 at 1:52 comment added Will Sawin FTA doesn't really use anything infinitary or choicy, since once you have a rough approximate solution, you can refine it to an exact solution by Newton's method.
Jun 30, 2015 at 1:35 answer added Bjørn Kjos-Hanssen timeline score: 25
Jun 30, 2015 at 0:54 comment added The Masked Avenger It might be useful to consider structures where FTA and analogues don't hold. I think that gives a more accurate picture than might be present from a RM equivalence in a theory which may not be as weak as you want to see things clearly.
Jun 30, 2015 at 0:35 history asked David Roberts CC BY-SA 3.0