Timeline for A version of Leray Hirsch better for local coefficients
Current License: CC BY-SA 3.0
2 events
| when toggle format | what | by | license | comment | |
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| Aug 31, 2016 at 7:56 | comment | added | tj_ | I don't believe that surjectivity of $H_\ast(E)\to H_\ast(B)$ lets the spectral sequence degenerate at $E^2$. Let the group $G$ be the semidirect product of $N$ (normal) and $Q$. Then the projection $q: G \to Q$ yields a surjection $q_\ast: H_\ast(BG,-) \to H_\ast(BQ,-)$. Take for example $BC_4 \to BD_8 \to BC_2$ where $D_8$ is the dihedral group of order 8 and $C_n$ cyclic of order $n$. I have no compuation for the homology ss at hand, but I know that the cohomology ss for the fibration doesn't stop at $E_2$. Therefore I'm pretty sure that the homology ss doesn't degenerate either. | |
| Aug 31, 2016 at 5:49 | history | asked | Hari Rau-Murthy | CC BY-SA 3.0 |