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Timeline for Models of the Kock-Lawvere axioms

Current License: CC BY-SA 4.0

10 events
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Oct 11, 2022 at 4:40 comment added მამუკა ჯიბლაძე Thanks, very interesting. Can one express this in terms of Hilbert schemes of some kind?
Oct 11, 2022 at 1:35 vote accept Alec Rhea
Oct 10, 2022 at 18:58 comment added user44143 @მამუკაჯიბლაძე, the ring $R_1$ is richer than it appears, and I think it includes infinitesimals with any of the algebraic properties used in those sources. E.g. $R_1$ contains 4 infinitesimals such that their squares and the product of any 3 are non-zero, even though their cubes are zero and the product of all 4 is zero, such as $w=(t_1+t_2+t_3)(t_4+t_5)$, $x=(t_1+t_2+t_3)(t_6+t_7)$, $y=(t_1+t_2+t_3)(t_8+t_9)$, $z=(t_1+t_2+t_3)(t_{10}+t_{11})$.
Oct 10, 2022 at 15:13 history edited user44143 CC BY-SA 4.0
added link to new question with some evidence of usefulness of this approach
Oct 10, 2022 at 12:00 comment added user44143 @GavinWraith, thanks; I fixed it.
Oct 10, 2022 at 11:58 history edited user44143 CC BY-SA 4.0
fixed typo, paraphrased highlighted sentences, and added to link for counter-classical statement
Oct 10, 2022 at 9:58 comment added მამუკა ჯიბლაძე Seems that there are several inequivalent ways to approach tuples of infinitesimally close points, as witnessed by the work of Breen and Messing in Combinatorial Differential Forms (2001) and Differential Geometry of Gerbes (2005). In particular, infinitesimal neighborhood of the diagonal $X\subset X^n$, infinitesimal cubes, infinitesimal simplices and what they denote by $\Delta^{(n)}$ all seem to be different.
Oct 10, 2022 at 8:36 comment added Gavin Wraith Isn't there a typo there? Should not "f(d) = cd" be "f(d) = f(0) + cd"?
Oct 9, 2022 at 23:23 comment added Alec Rhea These are very cool and close to exactly what I was looking for — I’m leaving the question open to see what else crops up, but if it’s still quiet after a few days this is excellent and I’ll accept. Thank you.
Oct 9, 2022 at 22:59 history answered user44143 CC BY-SA 4.0