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1 vote
0 answers
121 views

How does the Torelli theorem behave with respect to cyclic covering?

Let $Y\xrightarrow{2:1}\mathbb{P}^3$ be the double cover, branched over a quartic K3 surface $S$, known as quartic double solid. Assume $S$ is generic, we know that there is a Torelli theorem for $Y$ ...
user41650's user avatar
  • 1,962
7 votes
0 answers
315 views

Bondal-Orlov' theorem for noncommutative projective schemes

My question is very simple. Is Bondal-Orlov's theorem known for noncommutative projective schemes in the sense of Artin and Zhang? The commutative version is the following : Let $X, Y$ be smooth ...
Walterfield's user avatar
4 votes
0 answers
175 views

Relation between exotic sheaves in Achar's notes and in Bezrukavnikov-Mirkovic

I am trying to calculate explicitly a certain simple exotic sheaf (a simple object of the heart of the exotic t-structure on the Springer resolution, which is defined in Theorem 1.5.1 of Bezrukavnikov-...
Yellow Pig's user avatar
  • 2,540
5 votes
1 answer
232 views

On the bounded derived category of sheaves with coherent cohomology

Let $(X,\mathcal{O}_X)$ be a locally ringed space such that $\mathcal{O}_X$ is locally notherian, and let $\operatorname{Coh}(\mathcal{O}_X)$ be the category of coherent $\mathcal{O}_X$-modules. The ...
Fernando Peña Vázquez's user avatar
5 votes
1 answer
178 views

A pushout diagram of derived categories coming from an open cover of schemes

Suppose $X=U\cup V$ is the standard open cover of $X=\mathbb{P}^1$ by two affine lines. The descent theorems say that the diagram (with all arrows restriction maps) $\require{AMScd}$ \begin{CD} D(X) @&...
Kaiyi Chen's user avatar
3 votes
0 answers
110 views

What is the correct definition of intermediate Jacobian for this singular threefold?

I am considering blow up of $\mathcal{C}\subset(\mathbb{P}^1)^3$, $X=\operatorname{Bl}_{\mathcal{C}}(\mathbb{P}^1)^3$, where $\mathcal{C}$ is a curve given by $$\{s^2u=0\}\subset\mathbb{P}^1_{s:t}\...
user41650's user avatar
  • 1,962
2 votes
1 answer
146 views

Pullback morphism of a hyperplane inclusion is zero in the derived category

Let $L \subset \mathbb{C}^n$ be a hyperplane and let $i:L \to \mathbb{C}^n$ be the inclusion. Since $i$ is proper, we have induced maps $i^*: H^k_c(\mathbb{C}^n) \to H^k_c(L)$, and these maps are zero ...
Eduardo de Lorenzo's user avatar
6 votes
1 answer
565 views

Canonical comparison between $\infty$ and ordinary derived categories

This question is a follow-up to a previous question I asked. If $\mathcal{D}(\mathsf{A})$ is the derived $\infty$-category of an (ordinary) abelian category $\mathsf{A},$ then the homotopy category $h\...
Stahl's user avatar
  • 1,179
3 votes
1 answer
158 views

Pushforward of exceptional vector bundle is spherical for local P^2

I've been reading through a bit of the literature on stability conditions, and one of the models that has come up is the 'local projective plane'. Explicitly, this is the total space of the canonical ...
cdsb's user avatar
  • 275
3 votes
0 answers
88 views

Projective resolution of a quiver with relations

How do we compute the projective resolution of a representation of a quiver with relations. For example consider the Beilinson quiver $B_4$ $. with the relations ­$\{\alpha_j^k\alpha_i^{k-1}=\alpha_i^...
user52991's user avatar
  • 169
2 votes
1 answer
190 views

Find stratification to decompose constructible sheaf to constant parts (example from Wikipedia)

I have a question about techniques used in determining the stratification over which a constructible sheaf falls into even constant pieces demonstrated on this example from Wikipedia. Let $f:X = \text{...
user267839's user avatar
  • 5,780
3 votes
1 answer
176 views

Image, upto direct summands, of derived push-forward of resolution of singularities

Let $\mathcal C$ be a full subcategory (closed under isomorphism also) of an additive category $\mathcal A$. Then, $\text{add}(\mathcal C)$ is the full subcategory of $\mathcal A$ consisting of all ...
Alex's user avatar
  • 481
4 votes
1 answer
190 views

Some questions on derived pull-back and push-forward functors of proper birational morphism of Noetherian quasi-separated schemes

Let $f: X \to Y$ be a proper birational morphism of Noetherian quasi-separated schemes. We have the derived pull-back $Lf^*: D(QCoh(Y))\to D(QCoh(X))$ (https://stacks.math.columbia.edu/tag/06YI) and ...
strat's user avatar
  • 351
15 votes
1 answer
667 views

Why do we say IndCoh(X) is analogous to the set of distributions on X?

$\DeclareMathOperator\IndCoh{IndCoh}\DeclareMathOperator\QCoh{QCoh}$I've seen it written (for example, in Gaitsgory–Rozenblyum) that for a scheme $X$, the category $\IndCoh(X)$ is to be thought of as ...
JustLikeNumberTheory's user avatar
2 votes
1 answer
196 views

Perfect complexes of plane nodal cubic curve

Let $C\subset\mathbb{P}^2$ be a plane nodal cubic curve with a unique singular point $O$ at the origin. Then I consider its normalization, denoted by $\widetilde{C}$ and let $\pi:\widetilde{C}\...
user41650's user avatar
  • 1,962

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