Timeline for Counterexamples in algebraic topology?
Current License: CC BY-SA 2.5
8 events
| when toggle format | what | by | license | comment | |
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| Feb 14, 2011 at 18:24 | comment | added | Sam Isaacson | @Henrik, thanks for the correction. @Lennart, you're right; $p$-locally, the only delooping of $S^3$ is $\mathbf{H}\mathrm{P}^\infty$. | |
| Feb 14, 2011 at 18:20 | history | edited | Sam Isaacson | CC BY-SA 2.5 |
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| Feb 14, 2011 at 17:00 | comment | added | Lennart Meier | ad 1: it should be noted that this is really a global phenomenon. I think, at each prime the delooping is unique. | |
| Feb 14, 2011 at 15:51 | comment | added | Jeff Strom | Regarding ghosts: for each $n$, there are maps $f$ of finite complexes such that $\Sigma ^{2k} f$ induces $0$ on $\pi_*$ for $2k\leq n$. | |
| Feb 14, 2011 at 11:51 | comment | added | Johannes Ebert | Rectors example is really awesome. I cannot imagine uncountably many H-space structures on $S^3$. | |
| Feb 14, 2011 at 10:23 | comment | added | Johannes Ebert | And these phantoms are then zero on homology, cohomology and homotopy. | |
| Feb 14, 2011 at 9:52 | comment | added | HenrikRüping | i guess $if$ should be $fi$. | |
| Feb 14, 2011 at 7:08 | history | answered | Sam Isaacson | CC BY-SA 2.5 |