Skip to main content

All Questions

2 votes
0 answers
154 views

When is $D^+(QC(X))$ not the same as $D_{qc}(X)^+$ for schemes?

Let $QC(X)$ be the abelian category of quasicoherent sheaves on a scheme $X$. There is a functor $$D^+(QC(X)) \to D_{qc}(X)^+$$ which is an isomorphism if $X$ is Noetherian or quasi-compact with ...
davik's user avatar
  • 2,035
3 votes
0 answers
270 views

Algebraic Fukaya categories and mirror symmetry

Dominic Joyce and collaborators have outlined a programme to construct algebraic Fukaya categories on an algebraic symplectic manifold (“Fukaya categories” of complex Lagrangians in complex symplectic ...
Robert Hanson's user avatar
2 votes
1 answer
189 views

How to conclude the quasi-projective case of the derived McKay correspondence from the projective case?

I am currently trying to understand the paper "Mukai implies McKay" from Bridgeland, King and Reid (cf. here). Let me sum up the setting we find ourselves in: Let $M$ be a smooth quasi-...
OrdinaryAnon's user avatar
4 votes
2 answers
269 views

Does there exist a faithful exact embedding of $D^b(\dim(N)) \to D^b(\dim(N-1))$

$\DeclareMathOperator\Hom{Hom}$I am trying to show that if $X,Y$ are nice schemes with $\dim(X) > \dim(Y)$ there is no faithful FM transform $\Phi_{K}: D^b(X) \to D^b(Y)$. Does someone have a proof ...
user135743's user avatar
4 votes
0 answers
258 views

Has anyone studied the derived category of Higgs sheaves?

Let $X$ be a complex manifold and $\Omega^1_X$ be the sheaf of holomorphic $1$-forms on $X$. A Higgs bundle on $X$ is a holomorphic vector bundle $E$ together with a morphism of $\mathcal{O}_X$-...
Zhaoting Wei's user avatar
  • 8,767
2 votes
1 answer
175 views

liftability of isomorphism of curves in $P^3$

It is well known that the isomorphism between smooth curves $C$ and $C'$ in $\mathbb{P}^2$ can be lifted to an automorphism of $\mathbb{P}^2$ if degree of $C$ and $C'\geq 4$. Now I am considering an ...
user41650's user avatar
  • 1,962
5 votes
1 answer
384 views

What is the k-linear structure on the derived infinity category of quasi-coherent sheaves?

Let $f : X \overset{f}{\rightarrow} Y \overset{g}{\rightarrow} \mathrm{Spec} (k)$ be morphisms of schemes (feel free to add any hypothesis necessary). Let $\mathrm{QCoh}(Y)$ denote the derived (stable)...
Piotr D.'s user avatar
3 votes
0 answers
169 views

Relations between some categories of étale sheaves

I asked this question on math.stackexchange but nobody answers, so I try here even if I'm not sure my question is a research level one.. Let $X$ be a scheme over a number field $k$. Feel free to add ...
Marsault Chabat's user avatar
1 vote
1 answer
341 views

Tensor product and semisimplicity of perverse sheaves

Let $X/\mathbb{C}$ be a smooth algebraic variety. Let $D_c^b(X,\bar{\mathbb{Q}}_{\ell})$ be the category defined in 2.2.18, p.74 of "Faisceaux pervers" (by Beilinson, Bernstein and Deligne). ...
Doug Liu's user avatar
  • 545
1 vote
0 answers
99 views

Computing Grothendieck group of (unnodal) Enriques surface

Let $X$ be an unnodal Enriques surface together with an isotropic 10-sequence $\{ f_1, \dots, f_{10}\} \subset \operatorname{Num}(X)$, and let $F_i^\pm \in \operatorname{NS}(X)$ denote the two ...
cdsb's user avatar
  • 275
3 votes
1 answer
321 views

resolution property and perfect stacks

Recall that for a scheme $X$, it has the resolution property if every coherent sheaf $E$ on $X$, is the quotient of a finite locally free $\mathcal{O}_X$-module. On the other hand, Ben-Zvi-Nadler-...
prochet's user avatar
  • 3,452
1 vote
1 answer
214 views

Derived McKay correspondence between a weighted projective plane and a Hirzebruch surface

Let $k$ be an algebraically closed field of $\text{ch}(k) =0$. Let $\mathbb{P}(1,1,2)$ be the weighted projective plane of weight $(1,1,2)$ as a stack. Let $\mathbf{P}(1,1,2)$ be the weighted ...
Z.N's user avatar
  • 13
1 vote
0 answers
140 views

Intermediate Jacobian for small resolution of a singular Fano threefold?

I am mainly interested in the nodal Gushel-Mukai threefold. Let $X$ be a Gushel-Mukai threefold with one node, then by page 21 of the paper https://arxiv.org/pdf/1004.4724.pdf there is a short exact ...
user41650's user avatar
  • 1,962
1 vote
1 answer
173 views

Reference for localization distinguished triangles in the derived category of $\ell$-adic sheaves

Let us consider a variety $X$ over a field $k$ which is a finite field or an algebraic closure thereof. Let $\ell$ be a prime number different from the characteristic of $k$, and let $\Lambda = \...
Suzet's user avatar
  • 717
1 vote
0 answers
215 views

Characterization of morphisms of finite Tor-dimension by the hypertor functor

I am trying to have a concrete understanding of morphisms of finite Tor-dimension between arbitrary schemes. In Hartshorne’s book Residues and Duality,a morphism of schemes $f:X\rightarrow Y$ is said ...
Boris's user avatar
  • 569

15 30 50 per page
1
2
3 4 5
27