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3 votes
1 answer
294 views

Derived Koszul complex

Let $X$ be a projective variety over $\mathbb{C}$ and $V$ be a vector bundle over $X$. Let $\pi: V\to X$ be the natural projection. Let $i: X\to V$ be the zero section map. Let $V^\vee$ be the dual ...
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,...
8 votes
1 answer
324 views

$\infty$-categorical enhancement of $\mathsf{D}_\mathsf{B}(\mathsf{A})$

In this question, it is asked why we like to consider $\mathsf{D}_\textrm{qc}(X)$ rather than $\mathsf{D}(\mathsf{QCoh}(X)).$ Professor Cisinski answers rather convincingly that the $\infty$-...
4 votes
2 answers
413 views

“Geometric” vs Homotopical completion

There are two notions of completions of slightly different nature, and I am wondering if there is a precise statement relating them. The first one is the “homotopical” (or maybe it should be called ...
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 ...
17 votes
1 answer
1k views

How would you organize a cycle of seminars aimed at learning together some basics of Derived Algebraic Geometry?

This question is similar to this one because it's asking about a possible roadmap towards learning some derived algebraic geometry (DAG). But it's also different, because the goal is not to form a ...
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 ...
8 votes
1 answer
2k views

Elementary (English) reference for the cotangent complex?

I'm trying to understand cotangent complexes and their role in deformation theory, and later the statement that they're somehow natural in a derived scheme/stack. I understand that the standard ...
6 votes
0 answers
196 views

Specific Example of a Morphism of Schemes for which the Push-Pull Morphism is not an Isomorphism

Consider a Cartesian diagram of schemes as follows: $\require{AMScd} \begin{CD} X \times_Z Y @>{\tilde{\pi}}>> Y\\ @VV{\tilde{\phi}}V @VV{\phi}V\\ X @>{\pi}>> Z \end{CD}$ From the ...
14 votes
1 answer
953 views

Reference for symplectic structures on schemes?

My original goal was to read the PTVV paper Shifted Symplectic Structures https://arxiv.org/pdf/1111.3209v4.pdf. I was quickly humbled! Being told the theory ought to generalize symplectic structures ...
54 votes
2 answers
4k views

Connections between various generalized algebraic geometries (Toen-Vaquié, Durov, Diers, Lurie)?

As far as I know, there are four possible ways to generalize algebraic geometry by 'simply' replacing the basic category of rings with something similar but more general: $\bullet$ In the approach by ...
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 ...