Skip to main content
26 events
when toggle format what by license comment
S Jan 31, 2018 at 11:33 history suggested Helene Sigloch
removed tag "rigid analytic geometry"
Jan 31, 2018 at 10:09 review Suggested edits
S Jan 31, 2018 at 11:33
Sep 12, 2015 at 10:40 comment added მამუკა ჯიბლაძე Just googled to find a paper with the title Semistable principal $G$-bundles in positive characteristic :D
Sep 11, 2015 at 20:33 comment added მამუკა ჯიბლაძე If I am not mistaken, their $\mathcal X_G$ makes sense in positive characteristic too. True, their $G$ is a compact Lie group, but the basic examples come from algebraic groups definable in a characteristic-free way. I am not sure about the definition of semistability for principal bundles, though.
Sep 11, 2015 at 20:12 comment added Catherine Ray @მამუკა ჯიბლაძე I am having a lot of difficulty understanding why their construction should work in characteristic p. Grojnowksi's definition relies on choosing an isomorphism $S^1 \times S^1 \simeq E$ (for a complex elliptic curve $E$) to define the fixpoint set of an $S^1$-space $X$ over each point of $E$. How does their construction differ from Grojnowksi's to avoid using a lattice?
S Jul 15, 2015 at 6:27 history bounty ended CommunityBot
S Jul 15, 2015 at 6:27 history notice removed CommunityBot
Jul 9, 2015 at 21:52 comment added Catherine Ray Pardon my ignorance. What do you mean by "algebraically vary the curve"? My guess is that you are talking about an algebraic group action (rather than a continuous group action). If so, which algebraic group?
Jul 8, 2015 at 15:31 comment added Will Sawin Doesn't this suggest that it is not quite right to view the elliptic curve as varying continuously, but rather algebraically? For instance the $p$-torsion in the theory should depend on the elliptic curve's reduction modulo $p$, which does not depend continuously on its geometry.
Jul 8, 2015 at 2:19 history edited Catherine Ray CC BY-SA 3.0
deleted 4 characters in body
S Jul 7, 2015 at 4:46 history bounty started Matt Privman
S Jul 7, 2015 at 4:46 history notice added Matt Privman Improve details
Jul 7, 2015 at 4:39 comment added Catherine Ray @WillSawin I believe so, but it’s entirely obscure to me how to get from the outline of an equivariant derived theory to actually utilizing it in this circumstance. Grojnowski's construction has a very different flavour than Landweber-exact theories.
Jul 7, 2015 at 4:18 history edited Catherine Ray CC BY-SA 3.0
deleted 782 characters in body
Jul 7, 2015 at 4:05 history edited Catherine Ray CC BY-SA 3.0
Returned to the original question.; edited title
Jul 3, 2015 at 5:38 comment added მამუკა ჯიბლაძე Does not the Ginzburg-Kapranov-Vasserot version work everywhere?
Jul 3, 2015 at 5:03 history edited Catherine Ray CC BY-SA 3.0
deleted 8 characters in body
Jul 3, 2015 at 4:57 history edited Catherine Ray CC BY-SA 3.0
deleted 8 characters in body
Jul 3, 2015 at 4:51 history edited Catherine Ray CC BY-SA 3.0
added 49 characters in body
Jul 3, 2015 at 4:44 history edited Catherine Ray CC BY-SA 3.0
Moved Author's note.
Jun 27, 2015 at 17:46 history edited Catherine Ray CC BY-SA 3.0
added 32 characters in body
Jun 27, 2015 at 17:46 comment added Catherine Ray The case where $G = S^1$ collapses Grojnowski’s construction quite a bit. Here, $G = T, \mathfrak{g} = \mathfrak{t}$, and $Hom(T, S^1) = Hom(S^1, S^1) = \mathbb{Z}$. So $\text{Spec } E_T = \mathbb{Z} \otimes_{\mathbb{Z}} E$, which gives us $\text{Spec } E_T = E$.
Jun 27, 2015 at 17:45 comment added Catherine Ray @grghxy You're right. It’s not possible for $\text{Spec } E_{S^1}^*(pt)$ to give us the elliptic curve in the usual way (as a ring of global functions), rather, it's my understanding that we get $\text{Spec } E_{S^1}^*(pt) = E \otimes Hom(S^1, T)$, where we are identifying $Hom(S^1, T)$ with the lattices on the dual of the Lie algebra (of E), $S^1$ is the multiplicative circle group, and $T$ is a compact torus.
Jun 27, 2015 at 17:21 comment added Will Sawin Isn't this what the derived algebraic geometry theory of elliptic cohomology is for? I'm not an expert, but I am talking about this sort of thing: math.harvard.edu/~lurie/papers/survey.pdf
Jun 27, 2015 at 15:13 comment added grghxy Why do you say "$E$ is disconnected" in positive characteristic? That is false. And at the start you write that an elliptic curve is Spec of a ring, which is also false.
Jun 27, 2015 at 8:03 history asked Catherine Ray CC BY-SA 3.0