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Mar 15, 2020 at 13:37 history edited YCor
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Jul 12, 2010 at 3:11 answer added Bill Dubuque timeline score: 2
Feb 18, 2010 at 10:20 vote accept Franz Lemmermeyer
Feb 17, 2010 at 14:20 answer added Franz Lemmermeyer timeline score: 2
Feb 17, 2010 at 10:53 answer added Vladimir Dotsenko timeline score: 7
Feb 17, 2010 at 9:37 answer added Gjergji Zaimi timeline score: 11
Feb 16, 2010 at 15:29 comment added Kevin Buzzard On the other hand if p exactly divides a_j for j>0 but the a_i for 0<=i<j are allowed to be divisible by arbitrary powers of p then you can't possibly deduce irreducibility: consider (x^(m-j)-p)*(x^j-p^1000).
Feb 16, 2010 at 15:28 comment added Kevin Buzzard If you have a kink in the NP (i.e. if it's not just one line) then surely an arbitrarily small perturbation of your polynomial will factor over Q? Here's an example of something that is true: if f is monic of odd degree m, and p^2 divides all the a_i for 0<=i<=m-1, but p^3 doesn't divide a_0, then f will be irreducible, because the local extension will contain things of valuation 2/m and hence things of valuation 1/m.
Feb 16, 2010 at 14:51 history asked Franz Lemmermeyer CC BY-SA 2.5