bio | website | ma.utexas.edu/users/… |
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location | Austin, TX | |
age | ||
visits | member for | 4 years, 3 months |
seen | yesterday | |
stats | profile views | 1,652 |
Postdoc at UT Austin.
Sep 24 |
awarded | Autobiographer |
Sep 2 |
awarded | Revival |
Jul 20 |
awarded | Yearling |
Jul 6 |
awarded | Enlightened |
Jul 2 |
awarded | Curious |
Jun 15 |
comment |
in which sense is a mixed Hodge structure an extension of pure ones?
You are not missing anything. The term iterated extension means that (in your example): $W_1$ is an extension of $Gr_1$ by $W_0$, $W_2$ is an extension of $Gr_2$ by $W_1$ etc. So $H$ is "built up" from pure modules, in a similar way that a finite group is built as an iterated extension of finite simple groups. |
May 27 |
comment |
The general Smith homomorphism in bordism
strung : string ? |
May 25 |
comment |
Equivariant Sheaves, Local system
More naively, what you are asking for is the analogue of the statement that a 1-dimensional representation $\rho: G \to \mathbb C^\times$ of a group is a class function. The condition $m^\ast L = L \boxtimes L$ just says (roughly) that the stalk $L_{gh}$ at $gh$ is identified with $L_g \otimes L_h$. Thus we have $L_{ghg^{-1}} \simeq L_g \otimes L_h \otimes L_{g^{-1}} \simeq L_g \otimes L_{g^{-1}} \otimes L_h \simeq L_h$, which is (roughly) what it means to be $G$ equivariant. To get rid of the "roughly" you will need to express the above in terms of diagrams... |
May 20 |
comment |
What's the relationship between these two isomorphisms involving G and T?
I don't know how to answer your question, but let me try to clarify one thing that I probably said hastily in a talk some time. Of course, there is no equivalence (or even a map) of stacks $T/W \to G/G$ - the stabilizers are all wrong, even if the orbit spaces agree. Let us write $N=N_G(T)$. You do have a map of stacks $BN \to BG$, which gives a map on loop spaces $N/N \to G/G$ ($BN$ is what you write as $BT/W$). Inside $N/N$ you have a copy of $T/N = (T/T)/W$ which also maps to $G/G$. Not sure what else to say yet. |
Apr 16 |
answered | Equivariant derived category and invariant divisor |
Apr 8 |
comment |
Smooth mixed hodge modules - representations of fundamental group?
My expectation is that there will be no positive answer to your question. The data of a smooth (pure) Hodge module (aka variation of Hodge structure) involves a filtration on the holomorphic sections of the underlying vector bundle. This filtration is not flat, but rather satisfies the Griffiths transversality condition $\nabla \mathcal F^n \subseteq \mathcal F^{n-1}\otimes \Omega^1$. It doesn't look like it is possible to express these data and conditions in terms of the monodromy. |
Mar 29 |
comment |
Why should noncommutative CYs be dgas?
I think of Calabi-Yau as being a property of a dga rather than differential graded being a property of a CY algebra... |
Feb 14 |
answered | regular singularities and comparison isomorphism |
Jan 27 |
answered | Most general “finiteness of de Rham cohomology” statement for holonomic $D$-modules in the algebraic case? |
Dec 2 |
answered | How is a descent datum the same as a comodule structure? |
Nov 5 |
comment |
spectrum of an induced algebra
Ah, you got there first... |
Oct 8 |
revised |
A question about flag variety of $SL(n,\mathbb{C})$
Changed SL(2,C) to SL(n,C) in the first line. |
Oct 1 |
answered | For G a Lie group, can I make sense of G/G as a derived manifold in a nice way? |
Sep 5 |
comment |
Cobordism and finite sheeted covers of manifolds
Well, for the double cover $S^2 \to \mathbb RP^2$, $S^2$ is not cobordant to 2 copies of $\mathbb RP^2$. But maybe you wanted oriented manifolds? |
Sep 4 |
awarded | Civic Duty |