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2 votes
0 answers
119 views

dg-natural transformation between FM functors and Hom between kernels

The question is related to Morphism between Fourier-Mukai functors implies the morphism between kernels? Consider a complex smooth projective variety $X$ and the bounded derived category $D^b(X)$, it ...
user avatar
4 votes
0 answers
107 views

Perfect dg-modules under faithfully flat extension

Let $k \subseteq \bar{k}$ be an extension of fields (Orlov in the reference below seems to indicate the same thing will hold for faithfully flat maps but the case of fields is enough for me). On page ...
onefishtwofish's user avatar
1 vote
0 answers
72 views

Bound on Hochschild dimension of a dg-algebra

Consider a dg-algebra $A$, is there any way I can estimate the Hochschild dimension, or global dimension of $A$? More precisely the algebra that I am considering is the Endomorphism dg-algebra $\...
Felix's user avatar
  • 213
14 votes
1 answer
699 views

Who introduced the abstract definition of a DGA?

Differential graded algebras, or DGAs, are a basic object of study in many areas of modern mathematics. While they were present (implicitly at least) since the start of modern differential geometry, I ...
Bas Winkelman's user avatar
4 votes
0 answers
168 views

detecting a semi-free module from its bar-resolution

Let $A$ be a DG-algebra over a field (say $k$). A DG-module $M$ over $A$ is said to be semi-free if it admits an exhaustive filtration $0 = M_0 \subset M_1 \subset \ldots \subset M_p = M$ such that ...
Libli's user avatar
  • 7,300
13 votes
1 answer
983 views

De Rham and Koszul complexes

Consider the algebraic de Rham complex of the $n$-dimensional plane: this is merely $$\ldots\rightarrow Sym(V^*)\otimes\bigwedge^{k}V^*\rightarrow Sym(V^*)\otimes\bigwedge^{k+1}V^*\rightarrow\ldots $$...
A. S.'s user avatar
  • 528
23 votes
3 answers
2k views

Where does one go to learn about DG-algebras?

The theory of differential graded algebras (in char 0) and their modules has numerous applications in rational homotopy theory as well as algebraic geometry. I'm looking for a reasonably complete ...
Saal Hardali's user avatar
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5 votes
1 answer
782 views

Resolutions by free Differential Graded Algebras

I am struggling to find references for explicit computations of things like symmetric algebras and resolutions in the dg context. (any pointers in this direction would be highly appreciated!) I have ...
Yosemite Sam's user avatar
  • 1,889
8 votes
1 answer
346 views

If a faithfully flat extension of dg/A_$\infty$-algebra is formal, is the original algebra formal (over positive characteristic)?

Proposition 6.2 of Formality of DG algebras (after Kaledin) by Lunts reads (with a few additions to clarify notation): Let $k$ be a field of characteristic 0. Let $A$ be an $A_\infty$ algebra ...
Ben Webster's user avatar
  • 44.7k
23 votes
1 answer
966 views

Do DG-algebras have any sensible notion of integral closure?

Suppose R → S is a map of commutative differential graded algebras over a field of characteristic zero. Under what conditions can we say that there is a factorization R → R' → S ...
Tyler Lawson's user avatar
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