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Left adjoint for nested admissible categories

This question is motivated by the construction of the Kuznetsov component on a prime Fano threefold $X$ of index 1 (say genus $g \geq 6$, $g \neq 7, 9$): $$ D^b(X) = \langle Ku(X), E, \mathcal{O}_X \...
cdsb's user avatar
  • 317
3 votes
1 answer
285 views

Is there a notion of injective, projective, flat, dimension for a differential graded algebra?

Given a differential graded algebra $(A_\bullet,d)$, is there a well-defined notion of a K-injective, K-projective, K-flat dimension of a differential graded module, or even of the category of ...
54321user's user avatar
  • 1,716
3 votes
1 answer
468 views

Why should we study deformations of perfect complexes

What are the advantanges of studying deformation of perfect complexes over the classical theory of deformation of coherent sheaves? Any references which elaborates on the applications on deformation ...
Chen's user avatar
  • 1,593
3 votes
1 answer
422 views

Derived $\ell$-completion of $\mathbf{Q}_\ell$ sheaf?

I came across some notation that I’m having trouble understanding in Hansen-Scholze’s preprint ‘Relative Perversity.’ In the last paragraph of Proposition 3.4 there is the notation $A\widehat{\otimes^{...
Tomo's user avatar
  • 1,217
3 votes
0 answers
389 views

Status of motives in higher category theory: motives and algebraic cycles through a higher categorical perspective

A while ago this interesting question was asked Derived Algebraic Geometry and Chow Rings/Chow Motives. Primary question: Have there been any recent developments/advances on the above question? If not,...
Luqman Waheeduddin's user avatar
3 votes
0 answers
179 views

Étale morphisms of derived schemes and stacks

Conventions: In the below, unless otherwise stated, terms regarding derived algebraic geometry will follow the conventions of Yaylali. an algebraic stack will be a stack $\mathscr{S}$ over a base ...
Stahl's user avatar
  • 1,349
3 votes
0 answers
196 views

Divided power structure on $E_\infty$-algebras?

Let $A$ be a simplicial commutative ring, then it is known that the ideal of elements of degree $\ge1$ in the associated CDGA has a "DG divided power structure," which induces a divided ...
Curious's user avatar
  • 371
3 votes
0 answers
151 views

Is a derived scheme determined by classical + formal points?

Say we have a derived scheme over an algebraically closed field $X/k$, viewed as a functor $X : \operatorname{Aff}_k^{\operatorname{op}} \to \infty\operatorname{-Grpd}$ and we know its formal ...
E. KOW's user avatar
  • 834
3 votes
0 answers
187 views

Does "derived" make anything constant in non-flat families?

This is an extremely basic (and surely amateurish) question that might be about derived geometry. In usual algebraic geometry, if we have a flat projective morphism $f:X \to S$ with $S$ integral, and ...
adrian's user avatar
  • 318
3 votes
0 answers
309 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
3 votes
0 answers
451 views

Infinite dimensional dg-manifolds

In Def 2.5.1 in " Derived Quot schemes" by Ciocan-Fontanine and Kapranov, we can find the notion of dg-manifolds. In detail, let $X$ be a dg-scheme over $k$ ($k$ : an algebraic closed field ...
YkMz's user avatar
  • 889
3 votes
0 answers
398 views

Applications derived algebraic geometry in Morse theory

Have derived algebraic geometry been used to understand the topology of complex varieties? For example are there any applications in Morse theory? The reason I am asking this is two fold. First one is ...
user127776's user avatar
  • 5,901
3 votes
0 answers
213 views

Derived Chow varieties

I recently encountered the "Hidden Smoothness Principle" envisioned by Deligne, Drinfeld, Beilinson, Kontsevich that singularities occurring in certain moduli spaces is the consequence of ...
user127776's user avatar
  • 5,901
3 votes
0 answers
365 views

Construction of derived Quot schemes

I am studying the construction of derived Quot schemes in the paper Borisov, Katzarkov, and Sheshmani - “Shifted symplectic structures on derived Quot-stacks”. Derived quot stacks are constructed from ...
Walter field's user avatar
3 votes
0 answers
246 views

Derived category and L-function

For abelian varieties over $\mathbb{Q}$ $\mathscr{A}$ and $\mathscr{A}'$, if derived categories $D(\mathscr{A})$ and $D(\mathscr{A}')$ are equivalent then L-functions are same $L(s,\mathscr{A})=L(s,\...
user145752's user avatar
3 votes
0 answers
162 views

Homotopy Kan extensions, formally coherent functors and derived Schlessinger criterion

Let $k$ be a finite field. Denote by $discArt_k$ the category of Artinian rings with residue field $k$ and $Art_k$ the category of Artinian simplicial rings. Consider a functor $\mathcal{F}:disArt_k\...
curious math guy's user avatar
3 votes
0 answers
317 views

Reference request: Derived structure on the moduli stack of Higgs bundles

I am reading arXiv:1708.08124. When talking about the moduli stack of Higgs bundles on a projective curve $X$. It is said on page 59, first paragraph that It is often better to put derived ...
Chan Ki Fung's user avatar
3 votes
0 answers
336 views

DAG vs Classical algebraic geometry

I have a very vague question, but also a fairly specific wish. Namely, I'm wondering what the similarities and differences are between the theory of ordinary schemes on the one hand, and the theory of ...
Maanroof's user avatar
  • 213
3 votes
0 answers
180 views

vanishing of higher homotopy sheaves of cotangent complex

Let $X$ be a $\mathbb{C}$-scheme and suppose that there is an isomorphism (in the derived category of qc-sheaves on $X$) between the cotangent complex, $\mathbb{L}_{X}$, and its 0th homotopy sheaf, ...
user avatar
3 votes
0 answers
188 views

What are projective morphisms in derived algebraic geometry

I was curious if someone could point me to a reference or tell me if there is any notion of projective morphism between derived schemes? What about a notion of Proj? Also I am interested in what blow-...
Karl's user avatar
  • 431
3 votes
0 answers
286 views

Exterior tensor of derived categories of coherent sheaves

Let $X, Y$ be Noetherian perfect derived stacks over $S$ a regular perfect derived stack. Consider the exterior tensor functor $$\text{DCoh}(X) \otimes_{\text{DCoh}(S)} \text{DCoh}(Y) \rightarrow \...
math no more's user avatar
  • 1,423
3 votes
0 answers
502 views

Analysis of Eilenberg-MacLane Stacks

In a series of three papers from the fifties, Eilenberg and MacLane did a pretty exhaustive study of what we now call "Eilenberg-MacLane spaces" and used a lot of machinery to do it, e.g. Whitehead's $...
Jonathan Beardsley's user avatar
2 votes
1 answer
390 views

The stack of equivariant local system is quasi-smooth

Let $G$ be a (connected ?) algebraic group and $X$ a smooth, projective, and connected algebraic curve, both over an algebraically closed field $k$ of characteristic $0$. My questions are then as ...
Dat Minh Ha's user avatar
  • 1,516
2 votes
1 answer
131 views

Right adjoint of subcollection of semi-orthogonal decomposition

Suppose $X$ is a prime Fano threefold of index 1 such that $H = -K_X$ is ample. There is a full classification of the derived category of such threefolds depending on the genus of $X$; in the case ...
cdsb's user avatar
  • 317
2 votes
3 answers
480 views

Integral transform on noncommutative spaces

In their paper "Integral Transforms and Drinfeld Centers in Derived Algebraic Geometry" the authors show that for perfect stacks $X$ and $Y$ over $k$, and their $k$-linear $\infty$-categories of ...
Romie Banerjee's user avatar
2 votes
1 answer
246 views

Given a map of classifying spaces, can the target be described as a groupoid quotient of the source mod some action of some (co)kernel?

Let $H \to G$ be a homomorphism of affine algebraic groups (over characteristic $0$, if it matters). The case I care most about is when $H \to G$ is an inclusion. There is a corresponding map $f: \...
Theo Johnson-Freyd's user avatar
2 votes
1 answer
304 views

The exact sequence for a derived zero locus

For a locally free sheaf of rank one $L$ on a derived scheme and a morphism $s:L\rightarrow O_{X}$, we consider the derived zero locus of $s$ defined by the following derived fiber product $$\require{...
Yang's user avatar
  • 618
2 votes
1 answer
213 views

Derived quot schemes and the derived linearity locus

I am studying derived quot schemes in the paper Ciocan-Fontanine and Kapranov, “Derived Quot schemes” . On page 36 ~ 37, the derived linearity locus is defined. Let $S$ be a $\mathbb{Z}_-$-graded dg-...
Walter field's user avatar
2 votes
1 answer
199 views

Does every Artin $\infty$-stack have a formally étale cover by semi-free non-connective CDGAs?

The title essentially says it all. Feel free to assume as many finite generation conditions as you want. For example, I'm pretty sure the Chevalley-Eilenberg complex $\simeq \wedge^\bullet \mathfrak g^...
Charles Wang's user avatar
2 votes
1 answer
470 views

Two results about (shifted) symplectic structures

I am now interested in shifted symplectic structures. I found Zhang's results about symplectic structures (2011, p.3-4, arXiv link, Comm. Anal. Geom. 2017) and Pantev–Toen–Vaquié–Vezzosi's results ...
Walter field's user avatar
2 votes
1 answer
400 views

Confusion about DAG terminology

This question refers to higher and derived algebraic geometry as developed by Toen-Vezzosi, not by Lurie. I have seen two expository documents by Toen. In the first text, there is a definition: A ...
user avatar
2 votes
0 answers
157 views

Resolutions of semi free (or almost free) commutative dg algebras with finitely generated cohomology

Let $A^{\bullet}:=\{ \cdots \rightarrow A^i \overset{d^i}{\rightarrow} A^{i+1} \rightarrow \cdots \rightarrow A^{-1} \rightarrow A^0 \rightarrow 0 \rightarrow \cdots \}$ be a non-positively graded ...
YkMz's user avatar
  • 889
2 votes
0 answers
123 views

Moduli stack of doubly periodic complexes?

Let $\mathcal{A}$ be an abelian category. In HAG II Toen and Vessozi built a higher derived stack $X$ whose category of perfect complexes is $\text{Perf}(X)\simeq D^b(\mathcal{A})$. So $X$ is a good ...
Pulcinella's user avatar
  • 5,711
2 votes
0 answers
354 views

Higher-order HKR theorems?

Recall that Hochschild-Kostant-Rosenberg -type theorems identify certain smoothness conditions guaranteeing an isomorphism between the cotangent complex and (a shift of) the Hochschild homology of an ...
Tim Campion's user avatar
2 votes
0 answers
189 views

Is the homotopy limit of derived schemes along affine maps a derived scheme?

The title question is true in the setting of ordinary limits and ordinary schemes; that is, given an inverse limit of schemes along affine maps, the limit still lives in the category of schemes. I'd ...
Eric's user avatar
  • 301
2 votes
0 answers
235 views

Formally étale maps of animated $k$-algebras

In Lurie's DAG, he defines what it means for a natural transformation $T:\mathcal{F}\to\mathcal{F}'$ of functors $\mathcal{F},\mathcal{F}':\mathcal{SCR}\to\mathcal{S}$ to be formally étale. Namely, it ...
Eric's user avatar
  • 301
2 votes
0 answers
482 views

About derived divided power envelope

Assume $A$ is a $\mathbb{Z}_{(p)}$-algebra with ideal $I$ and $A,A/I$ are $p$-torsionfree. In this survey, Akhil Mathew defines the derived divided power envelope $LD_I(A)$ in Construction 7.15, after ...
Yang Chen's user avatar
  • 121
2 votes
0 answers
230 views

Lie bracket on the unshifted tangent complex?

My problem is as follows: if $X$ is a derived scheme, or derived stack, or any kind of a space where tangent complex makes sense, I guess there should be a lie bracket on its tangent complex, ...
dpistalo's user avatar
  • 121
2 votes
0 answers
213 views

Do dg schemes have derived points?

Working over a base field $k$ of characteristic $0$, say $K$ is a field (over $k$) and $X$ is a ("nice" if necessary) dg scheme in the sense of Toen-Vezzosi and others, and say $X^0$ is the reduced ...
Dmitry Vaintrob's user avatar
2 votes
0 answers
132 views

Compact generation of quasicoherent sheaves on mapping stack

Let $k$ be a field of characteristic $0$, and let $\mathcal{C}= \mathbf{Vect}_k^{\leq 0}$ be the $\infty$-category of vector spaces concentrated in degrees $\leq 0$. Consider the category $\mathbf{Pr}(...
Exit path's user avatar
  • 3,019
2 votes
0 answers
181 views

Why does the following construction describe the Serre functor?

In the book "Spectral Agebraic Geometry" that Jacob Lurie is currently writing, he gives a construction (11.1.5.1), which describes the Serre functor: it has already been shown that any proper $A$-...
John Doe's user avatar
2 votes
0 answers
113 views

quotient a scheme by a stratified vector bundle

Let $k$ be a field. Let $X$ be a $k$-scheme of finite type, normal and integral. We consider $f,g:R\rightarrow X$ an equivalence relation, surjective and such that it is a stratified vector bundle, i....
prochet's user avatar
  • 3,472
1 vote
1 answer
256 views

Examples when algebraic 1-stack = derived enhancement?

Are there any examples where a usual algebraic 1-stack $X$ and the corresponding derived stack enhancement $\mathbb{R}X$ coincide? Let me take an example from notes of Bertrand Toen, page 41 of https:/...
Robert Hanson's user avatar
1 vote
1 answer
201 views

Computing units in a dg-algebra

Let $\mathbb{G}_m= Spec(k[z,z^{-1}])$ be the usual multiplicative group over a field $k$ viewed as a discrete commutative dg-algebra, and let $A$ be some arbitrary commutative dg-algebra concentrated ...
Exit path's user avatar
  • 3,019
1 vote
1 answer
398 views

Is the pushforward of a closed immersion of spectral Deligne-Mumford stacks conservative?

Let $ X \hookrightarrow Y$ be a closed immersion of (connective) spectral Deligne-Mumford stacks, is $ i_* : Qcoh(X) \rightarrow Qcoh(Y)$ conservative? Somehow I couldn't find the statement in SAG...
Anette's user avatar
  • 595
1 vote
0 answers
62 views

Geometric stability conditions on calabi-yau's fibred over Fano always identical to geometric stability conditions on Fano

I apologize in advance for the long title. This question is motivated primarily by [2], with the explicit example of $\mathbb{P}^2$ and $\omega_{\mathbb{P}^2}$ computed in [3] and [1], respectively. ...
cdsb's user avatar
  • 317
1 vote
0 answers
109 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
  • 317
1 vote
0 answers
275 views

Fourier-Mukai transform is the derived functor

In Mukai's paper Duality between $D(X)$ and $D(\hat{X})$ with its application to Picard sheaves, Nagoya Math Journal, 1981, there is one sentence that puzzles me. Let $X$ be an abelian variety over an ...
Doug Liu's user avatar
  • 615
1 vote
0 answers
202 views

Is the cotangent complex sensitive to truncation?

$\DeclareMathOperator\Sym{Sym}\DeclareMathOperator\Spec{Spec}$If $V$ is a dg vector space (in positive degrees), we can view it as a derived scheme $V = \Sym V^*$. It has (co)tangent complex $V$ (and $...
Pulcinella's user avatar
  • 5,711
1 vote
0 answers
224 views

Two definitions of cotangent complex

I have reading a paper by Professor Pridham(https://arxiv.org/abs/0905.4044v4). Page 47-48 contains a comparison of the two definitions of the cotangent complex, but there is a part I don't understand....
Walter field's user avatar