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8 votes
2 answers
500 views

To compare the total, base and fiber spaces of two fiber bundles

Consider the following commutative diagram of the fiber bundles $% F\rightarrow E\rightarrow B$ and $F^{\prime }\rightarrow E^{\prime }\rightarrow B^{\prime }$ where $B^{\prime }$ is simply connected ...
16 votes
1 answer
808 views

"Rotated" version of the Atiyah-Hirzebruch spectral sequence

Let $G$ be a group, $X$ a topological space with $G$-action. For an Abelian group $A$, let $\mathcal{C}^n(X,A)$ be the group of $n$-cochains on $X$ with $A$ coefficients. We can treat this as a $G$-...
8 votes
1 answer
302 views

Torsion in the integral cohomology of $BPU_{n}$

I would like to prove that the integral cohomology of $BPU_{n}$ the classifying space of the projective unitary group of order $n$ has $n-$primary torsion. We have a fiber sequence of the form $BSU_{...
8 votes
1 answer
525 views

fibrations of classifying spaces - Leray Hirsch Theorem converse

Let $G$ be a topological group and let $H$ be a closed subgroup. Assume that $G \rightarrow G/H$ is a principal $H$-bundle. We have a fibration of classyifing spaces $$G/H \rightarrow BH \rightarrow ...
13 votes
1 answer
957 views

Relating two different approaches to the Atiyah-Hirzebruch Spectral Sequence

Given a (for simplicity connective) spectrum $E$ and a pointed CW-space $X$ there is "the" (homological) Atiyah-Hirzebruch spectral sequence $$E_{pq}^2 = \tilde{H}_p( X, \pi_q(E)) \Rightarrow \pi_{p+...
7 votes
0 answers
436 views

spectral sequence for a complex with two filtrations

Suppose $(C,d)$ is a chain complex: an abelian group with a map $d:C \to C$ such that $d^2 = 0$ (people like to assume $C$ is graded; if that helps - feel free to do so). A filtration is an ascending ...
6 votes
1 answer
284 views

Calculating topological index

Consider the space $X=BSL(8,\mathbb{C})/(\mathbb{Z}/2)$. The topological Brauer group of $X$ is given by $Br_{top}(X)=Tor(H^{3}(X;\mathbb{Z}))=\mathbb{Z}/2$. I'm studying concepts of topological ...
5 votes
0 answers
544 views

Strong Convergence vs Conditional Convergence for Spectral Sequences (Is there a simple explanation?)

I am curious if there is a relatively simple explanation of what is the difference between strong convergence and conditional convergence for Spectral Sequences? (Hopefully a simpler explanation than ...
12 votes
2 answers
1k views

Differentials in the Adams Spectral Sequence for spheres at the prime p=2

How does one compute the differentials in the Adams Spectral Sequence for spheres at the prime 2 in the range $13\le t-s\le 20$? There seem to be 6 nonzero differentials, and at this point I only ...
4 votes
1 answer
195 views

Can Bockstein Spectral Sequence detect multiple summands of the same power, in homology?

I understand that the differential $d^k$ of the Bockstein S.S. (mod p) is nonzero iff the homology $H_*(X;\mathbb{Z})$ has summand of the form $\mathbb{Z}/p^k$. How about for multiple summands in the ...
3 votes
1 answer
260 views

non-simple local coefficient system on a fibration of classifying spaces

Long story short; I posted in MSE https://math.stackexchange.com/questions/2500745/local-system-of-coefficients-on-a-fibration-of-classyfing-spaces It is well known that if $G$ is a lie group ...
15 votes
2 answers
1k views

Pullback and homology

Suppose I have two maps of topological spaces, $f:X\rightarrow B$ and $g:Y\rightarrow B$, such that $f$ induces a homology isomorphism and $g$ is a fibration and $B$ is connected. Is it true that the ...
2 votes
1 answer
712 views

Oriented Bordism Group and Un-Oriented Bordism Group of points $pt$

Do we know, or are there any References that list down complete oriented and unoriented Bordism Group $Ω_{n,O}(pt)$ and $Ω_{n,SO}(pt)$ of points $pt$ for dimensions $n=1,2,...,10$? Here are some ...
15 votes
1 answer
988 views

Why is it difficult to obtain the next differential in a spectral sequence?

I am following Hatcher's notes on spectral sequences. On page 522 an exact couple $(A, E, i, j, k)$ is defined. You can construct a derived exact couple easily from this to get your desired $E'$ ...
7 votes
0 answers
168 views

Adams spectral sequence for loop spaces

Let $X = \Omega_0^3S^3$ a connected component of $\Omega^3S^3$. I am interested in explicit construction of spectral sequence converging to odd prime torsion in homotopy groups of $X$. There is a ...
128 votes
12 answers
12k views

Spectral sequences: opening the black box slowly with an example

My friend and I are attempting to learn about spectral sequences at the moment, and we've noticed a common theme in books about spectral sequences: no one seems to like talking about differentials. ...
3 votes
0 answers
234 views

How can I find the differential in the Serre spectral sequence for this sphere fibration?

Consider the assocaited sphere bundle $$S(E) \to \mathbb{P}^n$$ for the vector bundle $\mathcal{O}(k)\oplus \mathcal{O}(l) \to \mathbb{P}^n$. Is there a way to determine the differentials $$ d_4^{p,m}:...
6 votes
1 answer
399 views

Leray-Serre spectral sequence for algebraic groups

Let $G$ be a semisimple, simply-connected, complex algebraic group. Fix a Borel subgroup $B$ and let $P$ be a parabolic subgroup properly containing $B$. If $M$ is a $B$-module, then we have the Leray-...
2 votes
0 answers
151 views

Monodromy and simple system of local coefficients

I was interested in the following question: if one has a fibration $F\to E\to B$ there is associated a monodromy map, that is basically an action of the fundamental group $\pi_1(B)$ on the ...
8 votes
1 answer
363 views

Adams spectral sequence and short exact sequences. Some clarifications

as the title suggests I'm looking for some clarifications in the computations of the ext charts of some $A(1)$-modules arising as extensions of other modules. In particular, I've the following example ...
12 votes
1 answer
961 views

What is the first interesting matric Toda bracket in the stable homotopy of the sphere?

Feel free to gloss ‘interesting’ as you see fit. One way: 1. What is the lowest degree matric Toda bracket in $\pi_\ast(S)$ that doesn't contain zero? By ‘degree’ I mean total homotopical degree, ...
6 votes
0 answers
167 views

A spectral sequence problem in Alejandro Adem's Paper

I am reading Adem's paper Periodic Complexes and Group actions. But I can't give an argument about a statement on spectral sequences. Suppose you have an orientable fibration of CW-complexes like ...
3 votes
0 answers
163 views

Question about the precise statement of Leray spectral sequences and a simple example

On Bott's paper "Homogeneous vector bundles" there is the following statement of Leray spectral sequence: Let $X$ and $Y$ be paracompact and locally compact spaces and $f : Y \to X$ be a proper map....
7 votes
0 answers
149 views

Cohomology of Lie group $E_8$, e.g. $H^d(E_8,\mathbb{R}/\mathbb{Z})$

What is the $d$-th cohomology of a Lie group $E_8$, say $H^d(E_8,\mathbb{R}/\mathbb{Z})$ with $\mathbb{R}/\mathbb{Z}$ coefficient? I suppose that there are many nontrivial groups of $H^d(E_8,\mathbb{...
20 votes
1 answer
1k views

Torsion in the Atiyah–Hirzebruch spectral sequence of a classifying space

Let $G$ be a compact, connected Lie group. There is an Atiyah–Hirzebruch spectral sequence $$H^*(BG;K^*) \implies K^*(BG)$$ connecting $H^*BG$, which generally contains torsion, with $K^*BG \cong \...
2 votes
0 answers
71 views

Connected topological/Lie group $H$ and $Q$, inflate $Q$-cocycle to coboundary in $H$

I am interested in finding mathematical examples and criteria of inflating $Q$-cocycle to coboundary in $H$, under the requirement: (1) Both $H$ and $Q$ are connected topological groups or Lie groups (...
3 votes
0 answers
310 views

Functoriality of Leray homology spectral sequences of fibrations

Let $p\colon E\to B$ and $p'\colon E'\to B'$ be two fibrations. Assume for simplicity that $B,B'$ are simply connected. Let we have morphism of these fibrations, i.e. two continuous maps $$f\colon E\...
2 votes
0 answers
108 views

Relating inflation maps from spectral sequences in lower and higher dimensions

The spectral sequence has some nice property. Consider $ N \to G \overset{R}{\to} Q $ and $G/N=Q$. There is a spectral sequence $\{E^{p,q}_n, d_n\}$ with: (i) The differential is defined as a map $...
1 vote
0 answers
109 views

Empty regions on the second list of unstable Adams spectral sequence

Define $\phi(n) = 4n - 2$. Is there a proof that on the second list of unstable Adams spectral sequence (for all spheres) there are no elements in squares $(n, m)$ such that $m < \phi(n)$. The ...
5 votes
2 answers
526 views

The inability to continue a fibration sequence even when a delooping exists

$\newcommand{\i}{\iota}$ The general notion that I am trying to disprove is that if we are given a fibration $X \to Y$ with fiber $F$ such that the delooping $BF$ exists, that there is a map $Y \to BF$...
10 votes
1 answer
370 views

Adams Spectral sequence for computing some $B$-bordism groups

As the title suggests, I'm trying to apply the Adams Spectral sequence to get some insights of the bordism group $$ \Omega_4(\xi)= \pi_4(M\xi)$$ where $\xi \colon BSpin \times K(D_{2n},1) \to BSO$ is ...
5 votes
2 answers
651 views

Inflate a finite-group cocycle into coboundary in non-Abelian groups

Edit: In case that there is no solution for the original question, I modify to enrich the question. We like to ask a possible specific inflation a $H^3(Q, \mathbb{R} /\mathbb{Z})$ cocycle with a ...
5 votes
1 answer
653 views

Spin bordism group of classifying space $BG$ with a finite Abelian $G$

The spin bordism group for the classifying space $BG$ of group $G$ can be denoted as $\Omega^{Spin}_d(BG)$. For example, $\Omega^{Spin}_d(pt)$ are computed by Anderson-Brown-Peterson (D. W. Anderson, ...
0 votes
1 answer
143 views

Trivialize a cup-product 2-cocycle of $G$ in a larger group $J$

I like to ask a simple question: how to trivialize a cup-product 2-cocycle of $G$ into a 2-coboundary of $J$ in a larger group $J$. Let us take a nontrivial 2-cocycle $\omega_3^G(g_a, g_b) \in H^2(G,\...
11 votes
2 answers
656 views

$G$ cocycle split and trivialized to a coboundary in $J$, given a group homomorphism $J \overset{r}{\rightarrow} G$

Consider a generic nontrivial 3-cocycle $\omega_3^G(g_1,g_2,g_3) \in H^3(G,U(1))$ in the cohomology group of $G$ with $U(1)=\mathbb{R}/\mathbb{Z}$ coefficient. In otherwords, here the 3-cocycle $\...
4 votes
1 answer
394 views

$SO(3)$ 2-cocycle trivialized to a 2-coboundary in $SU(2)$?

I was trying to understand this interesting question by example. Let me follow their previous discussion and ask: Let a generic nontrivial 2-cocycle $\omega_2^G(g_1,g_2) \in H^2(G,\mathbb{R}/\mathbb{...
2 votes
1 answer
264 views

Trivialize a cup-product 3-cocycle of $G$ in a larger group $J$

Inspired by this question, let us take a nontrivial 3-cocycle $\omega_3^G(g_a, g_b, g_c) \in H^3(G,\mathbb{R}/\mathbb{Z})$ in the cohomology group of $G$ with $U(1)=\mathbb{R}/\mathbb{Z}$ coefficient. ...
3 votes
0 answers
120 views

Trivialize a cocycle of a continuous Lie group-cohomology to a coboundary

Someone recently asks a question $SO(3)$ 2-cocycle trivialized to a 2-coboundary in $SU(2)$? now inspires me to revisit an earlier general question to ask an example of 3-cocycle $\omega_3^G$ of a ...
6 votes
1 answer
609 views

References for properties of Atiyah-Hirzebruch Spectral Sequence for a spectrum $X$ and generalised homology theory $MSpin_*$

Currently I'm working on the following version of the AHSS $$ E^2_{pq}\cong H_p(M\eta; MSpin_q(\ast))\Rightarrow MSpin_{p+q}(M\eta)$$ where $\eta \colon B \to BSO$ is a stable vector bundle, and $M\...
2 votes
0 answers
206 views

Cohomology of fiber bundles with non constant coefficients

Let $E \to B$ be a topological fiber bundle. We know that the Serre spectral sequence allows you to compute the cohomology of $E$ with constant coefficient in terms of the cohomology of $F$ and the ...
7 votes
1 answer
506 views

$G$ cocycle split to a coboundary in $J$, via a group extension

Consider a generic nontrivial $d$-cocycle $\omega_d^G \in H^d(G,U(1))$ in the cohomology group of a group $G$ with $U(1)=\mathbb{R}/\mathbb{Z}$ coefficient. In otherwords, here the $d$-cocycle $\...
11 votes
1 answer
496 views

Identification of a Serre Spectral Seq. via Thom Isomorphism with the Atiyah-Hirzebruch Spectral Seq

Let $\xi_n$ be an orientable $n$-dimensional vector bundle over a pointed space $B_n$. We can consider the relative Serre Spectral Sequence $$ H_p(B_n; h_q(D(\xi_n|\ast),S(\xi_n|\ast))\Rightarrow h_{p+...
7 votes
1 answer
663 views

Explicit 2-cocycle from a 2nd cohomology group $H^2[Q_8 \times \mathbb{Z}/2\mathbb{Z}, U(1)]$

I would like to know the explicit expression of 2-cocycle from a 2nd cohomology group $H^2[Q_8 \times \mathbb{Z}/2\mathbb{Z}, U(1)]$ with $U(1)\equiv \mathbb{R}/\mathbb{Z}$ coefficient, or namely $H^2[...
3 votes
0 answers
274 views

Is there a spectral sequence for borel-moore homology associated to a whitney filtration?

Consider a Whitney stratified space $$ \varnothing = X_{-1} \subseteq X_0 \subseteq X_1 \subseteq \cdots \subseteq X_n $$ is there a spectral sequence for borel-moore homology which depends on the ...
2 votes
0 answers
326 views

A version of Leray Hirsch better for local coefficients

Let $F \hookrightarrow E \to B$ be a fibration, and let everything be over a field $k$. The leray hirsch theorem in its usual form says that the (homology) cohomology spectral sequence degenerates at (...
15 votes
2 answers
1k views

Where does the primary obstruction of a fibration show up in its spectral sequence?

Let $f\colon\thinspace E\to B$ be a Serre fibration whose fibre $F$ is $k-1$-connected, $k\geq 1$. Assume $B$ is a connected CW complex. Then the primary obstruction to the existence of a cross ...
4 votes
1 answer
2k views

Tensor product of spectral sequences?

I'm wondering about a cross product for spectral sequences. I've got an idea, and I wonder if it is written up anywhere, or if it even holds water. Let's start with three spectral sequences, $E, F$ ...
8 votes
1 answer
503 views

Cohomology ring of a fiberwise join

I am very interested in the cohomology ring of the following construction. Let $f: Y\to X$ be a map between (connected) topological spaces. Suppose that the image of the map $f^*:H^*(X) \to H^*(Y)$ is ...
5 votes
0 answers
290 views

Two natural maps asssociated with the nerve of a cover

Let $X$ be a nice (e.g. paracompact, locally contractible) topological space, and let $\mathcal{U}=\{U_i\}_{i\in I}$ be an open cover of $X$. Also denote by $N$ the (topological realization of) the ...
5 votes
0 answers
229 views

Bockstein morphism of spectral sequences

Given an omega spectrum $E$, there is a type of chern character map given by its rationalization $$r:E\to E\wedge M\mathbb{R}\;,$$ where $M\mathbb{R}$ denotes a Moore spectrum. The cofiber of the map $...