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4 votes
0 answers
127 views

Minimal Model for $\mathbb{CP}^2 \# \mathbb{CP}^2 \# \mathbb{CP}^2$

I'm a grad student studying non-negative curvature on simply-connected manifolds and the conjectured relationship with rational homotopy theory. The rational homotopy groups (and so the number of ...
Russ Phelan's user avatar
5 votes
1 answer
346 views

Analogues of Sullivan Theory at a prime for coformality

In rational homotopy theory, one can study the rational homotopy and cohomology categories via an algebraic structure, respectively the rational Lie Algebra model and the Sullivan cdga model. If I am ...
Andrea Marino's user avatar
4 votes
0 answers
170 views

Relation between $Tor_{C^*(BG;K)}(K,K) $ and $K^G$?

Let $K$ be an algebraically closed field and $G$ a group. Given a dg-algebra $A$, a left $A$-module $M$ and a right $A$-module $N$ let $Tor_A(M,N)$ denote the homology of the derived tensor product $M ...
Hadrian Heine's user avatar
-5 votes
1 answer
409 views

Computing $H^*(BDiff(W_{\infty},D^{\infty});\mathbb{Q})$ via Mumford-Morita-Miller classes

Galatius and Randal-Williams proved the following generalized Mumford conjecture in their joint paper, "Stable Moduli spaces of High Dimensional Manifolds". For each characteristic class of oriented $...
Sergio Charles's user avatar
0 votes
1 answer
174 views

Compute the rational cohomology ring $H^*(M;\mathbb{Q})$ of a product of Lie groups (and their quotients)

As the following product is a bit unfamiliar to me: How do we compute the rational cohomology ring $H^*(M;\mathbb{Q})$ of the product of Lie groups: $M=SO(n_1)\times U(n_2)\times SU(n_3)\times (...
Sergio Charles's user avatar
2 votes
1 answer
660 views

Show that the rational cohomology ring $H^*(M;\mathbb{Q})$ needs at least two generators

Let $M$ be a simply connected closed Riemannian manifold. How does one find a necessary condition going both ways that may be imposed on $M$ (perhaps on the curvature of $M$ and on torsion) which ...
Sergio Charles's user avatar
13 votes
1 answer
469 views

A cdga for compactly supported cohomology (à la Sullivan's algebra of polynomial forms)

Let $M$ be a smooth manifold, and let $\Omega^\bullet(M)$ be the commutative dg-algebra of differential forms on $M$. It is quasi-isomorphic to the dg-algebra of singular cochains on $M$. If $M$ is no ...
Dan Petersen's user avatar
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