Forking and invariant measures in NIP theories

2023/07/20 by Pillay, Anand, Stonestrom, Atticus
#FOS: Mathematics #Logic (math.LO)

paper · doi:10.48550/arxiv.2307.11037

Abstract

We give an example of an NIP theory T in which there is a formula that does not fork over \varnothing but has measure 0 under any global \varnothing-invariant Keisler measure, and we show that this cannot occur if T is also first-order amenable.

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