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History of tag 0CXM

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type time link
changed the statement and the proof 2021-04-10 8be4594
Finish Artin's theorem on contractions

Still a bit rough
changed the statement 2018-01-31 c2868d0
W ---> Z

Thanks to Tanya Kraushal Srivasta
https://stacks.math.columbia.edu/tag/0CXM#comment-2985
assigned tag 0CXM 2016-11-06 0a3bfd5
Tags: Added new tags
created statement with label lemma-base-change-versal in artin.tex 2016-11-06 7a43b50
Strong formal effectiveness => openness versality

Actually not hard to prove and you only need to check on first order
thickenings.

Bhargav's example from c31011d shows that strong formal effectiveness
does not always hold. But what about strong formal effectiveness
where the thickenings are always first order (between any two, not
just between consecutive indices)? This is the only thing needed for
the argument here, so it would be nice if it was true for algebraic
stacks in general.