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Jun 28, 2016 at 14:28 vote accept Ilan Barnea
Jun 28, 2016 at 8:41 answer added Jeremy Rickard timeline score: 1
Jun 27, 2016 at 18:13 history edited Ilan Barnea CC BY-SA 3.0
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Jun 27, 2016 at 13:54 comment added Jeremy Rickard I've not checked that this fixes all the problems, hence just a comment. But the idea of the definition of $h^*_p$ seems to be that if there is no $\sigma$ with $a\in p^\sigma A\setminus p^{\sigma+1} A$ then $h^*_p(a)$ should be "big", and $l_p(A)$ is chosen as the smallest ordinal bigger than $h^*_p(b)$ for all those $b\in A$ which already have $h^*_p(b)$ defined. He'd probably have chosen $\infty$ instead of $l_p(A)$ except that then you have to say which infinite ordinals are greater than $\infty$. But if you do choose $\infty$, a notional symbol greater than all ordinals, does that work?
Jun 27, 2016 at 10:50 comment added Ilan Barnea Exactly, this shows that the statement cannot be true
Jun 27, 2016 at 10:48 comment added Jeremy Rickard Oh, OK. You meant that's the inequality that would be true if the statement were true, rather than the inequality that is true.
Jun 27, 2016 at 10:46 comment added Ilan Barnea The statement is "$h^*_p$ does not diminish under homomorphisms" so $h_p^*(f(a))\geq h_p^*(a)$
Jun 27, 2016 at 10:43 comment added Jeremy Rickard I think you meant to write $0=h^*_p(f(a))\leq h^*_p(a)$?
Jun 27, 2016 at 10:34 history asked Ilan Barnea CC BY-SA 3.0