Timeline for What are explicit obstructions to realizability of formal group laws as complex-oriented ring spectra?
Current License: CC BY-SA 3.0
9 events
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| May 5, 2015 at 14:41 | comment | added | Tyler Lawson | Regarding your edit, if you impose the constraint that your formal group law comes from a graded ring $R$ with a map $MU^* \to R$ of graded rings, the additive formal group is indeed the only possible formal group law on the graded ring $\Bbb F_p$. | |
| May 5, 2015 at 12:26 | history | edited | Catherine Ray | CC BY-SA 3.0 |
added explicit example, general formula for obstructions is still unclear.
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| Apr 27, 2015 at 12:18 | history | edited | Catherine Ray | CC BY-SA 3.0 |
added 72 characters in body
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| Apr 20, 2015 at 11:55 | answer | added | Neil Strickland | timeline score: 9 | |
| Apr 19, 2015 at 22:38 | comment | added | Lennart Meier | I do not know the answer. In particular, I do not know whether realization is possible if I kill a non-regular sequence from $MU_*$ or related spectra, e.g. if I do something like $BP\langle 2 \rangle_* /(v_1^2, v_1v_2, v_2^2)$. | |
| Apr 18, 2015 at 9:02 | comment | added | მამუკა ჯიბლაძე | Just a suggestion - start from some "subtle" $E$ and either take arbitrary subring $R\subset\pi_*(E)$ containing the image of $L\to\pi_*(E)$ or, in the opposite direction, take arbitrary ring homomorphism $\pi_*(E)\to R$ to some other ring. It is intuitively clear that $R$ might be "arbitrarily bad". I realize this is very imprecise but somehow it gives rise to a feeling that it must not be that hard to stumble on counterexamples... | |
| Apr 18, 2015 at 5:54 | comment | added | Tyler Lawson | This is a good question. There are examples of explicit obstructions when you ask for more structure on $E$ than simply being a ring spectrum. I do not know an example where realizability is impossible. | |
| Apr 18, 2015 at 4:48 | history | edited | Catherine Ray | CC BY-SA 3.0 |
added 108 characters in body
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| Apr 18, 2015 at 3:46 | history | asked | Catherine Ray | CC BY-SA 3.0 |