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Questions tagged [t-structure]

$t$-structure is a structure imposed on triangulated categories, first introduced in Beilinson, Bernstein, Deligne's "Faisceaux Pervers".

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
2 votes
0 answers
198 views

Are there any relations between perverse t-structure (cohomologies) and standard t-structure (cohomologies)?

I'm reading the Corollary 3.2.3. in Exponential motives by J. Fresan and P. Jossen. The authors use the following statement in the proof of Corollary 3.2.3: let $C$ be any object in the derived ...
Mathstudent's user avatar
2 votes
0 answers
126 views

Local systems as a Serre subcategory of the category of perverse sheaves

Let $X$ be an algebraic variety. Let $Perv(X)$ be the (abelian) category of perverse sheaves on $X$ and let $Loc^{ft}(X)$ be the subcategory of local systems with finitely-generated stalks. It is ...
Laurent Cote's user avatar
2 votes
0 answers
122 views

When semi-simple subcategories "extend" to hearts of t-structures?

Let $A$ be a semi-simple abelian subcategory of a triangulated category $C$ that "generates" $A$ (that is, $C$ equals its own smallest triangulated subcategory that is closed under direct ...
Mikhail Bondarko's user avatar
5 votes
0 answers
297 views

Tensor product of t-structures compatible with filtered colimits

Let $C,D$ be two stable presentable $(\infty,1)$-categories, equipped with accessible t-structures. Then you can define an accessible t-structure on $C\otimes D$ by having $(C\otimes D)_{\geq 0}$ be ...
dhy's user avatar
  • 5,918
5 votes
0 answers
174 views

Which t-structure extend from subcategories of compact objects uniquely?

Let $T$ be a compactly generated triangulated category, that is, $T$ is closed with respect to small coproducts and equals its own smallest triangulated subcategory closed with respect to coproducts ...
Mikhail Bondarko's user avatar
4 votes
0 answers
135 views

Bounded derived categories of which smooth projectives possess bounded t-structures whose hearts have enough injectives?

For which smooth projective $P$ over a field there exists a bounded $t$-structure $t$ on the bounded derived category of coherent sheaves $D^b(P)$ such the heart $Ht$ of $t$ has enough injectives? ...
Mikhail Bondarko's user avatar
7 votes
1 answer
612 views

Heart of a bounded $t$-structure on the derived category of coherent sheaves

Let $X$ be an elliptic curve and $D(X)$ the bounded derived category of $Coh(X)$, coherent sheaves on $X$. If $(D^{\leq 0}, D^{>0})$ is a bounded $t$-structure, then can we already say that the ...
user12344321's user avatar
2 votes
0 answers
104 views

Semi-stable bundles as a heart of a t-structure

Given an algebraic curve, the category of semi-stable vector bundles of fixed slope forms an abelian category see here page 2. This is surprising as the vector bundles themselves are not an abelian ...
user127776's user avatar
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4 votes
0 answers
303 views

Which derived categories of coherent sheaves are equivalent (or "$t$-related") to derived categories of rings?

As far as I understand, it was Beilinson who proved that the bounded derived category of coherent sheaves $D^b(\mathbb{P}^n)$ is equivalent to the bounded derived category of a certain (non-...
Mikhail Bondarko's user avatar
4 votes
0 answers
192 views

Who introduced the heart ($\mathcal{C}^\heartsuit$) notation in the context of $t$-structures on triangulated categories?

In the context of $t$-structures ([Wikipedia], [nLab], [Notes I], [Notes II], [HA, Definition 1.2.1.11)], [BBD, Définition 1.3.1]), one often writes $\mathcal{C}^\heartsuit$ for the heart of a ...
Emily's user avatar
  • 11.5k
7 votes
2 answers
519 views

Chromatic t-structures?

Questions: Fix a prime $p$ and $n \in \mathbb N_{\geq 1}$. Does the category $Sp_{K(n)}$ of $K(n)$-local spectra admit a nontrivial $t$-structure? By "nontrivial", I simply mean that $\{0\}...
Tim Campion's user avatar
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11 votes
2 answers
1k views

The relation between t-structures and derived category

Let $\mathcal{D}$ be a triangulated category and a $t$-structure $(\mathcal{D}^{\leq 0},\mathcal{D}^{\geq 0})$ on $\mathcal{D}$. The heart of the $t$-structure, $\mathcal{A}=\mathcal{D}^{\leq 0} \cap ...
Amos Kaminski's user avatar
3 votes
1 answer
464 views

Monoidality of truncation of spectra

If $X$ is a spectrum, we have a notion of its connective part $X_{\le 0}$ and the corresponding notion of truncation $X_{[i:j]} = X_{\le j}/X_{\le i-1}$, where $X_{\le j}$ is deduced from $X_{\le 0}$ ...
Dmitry Vaintrob's user avatar
5 votes
2 answers
972 views

On various relations between "additional axioms" for AB4 and Grothendieck abelian categories

Let $A$ be an abelian category that has a generator and satisfies the AB4 axiom. I would like to understand (better) the relations between various additional "restrictions" on $A$. So here is my list ...
Mikhail Bondarko's user avatar

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