Oriented Cobordism Rings - MathOverflow most recent 30 from http://mathoverflow.net2013-05-26T09:30:46Zhttp://mathoverflow.net/feeds/question/26655http://www.creativecommons.org/licenses/by-nc/2.5/rdfhttp://mathoverflow.net/questions/26655/oriented-cobordism-ringsOriented Cobordism RingsJuanSOS2010-06-01T02:27:38Z2010-06-01T07:45:22Z
<p>Hey everybody!
I was wondering if anybody had available the calculation of the Oriented cobordism groups in dimensions higher than 10? Or if anybody knew if there is another kind of torsion beside 2-torsion in them? (e.g. I know that $\Omega^5$ is $\mathbb{Z}_2$, is there a group with n-torsion with n distinct from 2?).
Thanx,
Refferences are also appreciated....</p>
http://mathoverflow.net/questions/26655/oriented-cobordism-rings/26656#26656Answer by Tyler Lawson for Oriented Cobordism RingsTyler Lawson2010-06-01T02:43:52Z2010-06-01T02:43:52Z<p>There is no torsion other than 2-primary torsion in the oriented bordism ring. One has that after inverting 2, the oriented bordism ring is a polynomial algebra on generators in degrees which are multiples of 4:
<code>$$
\Omega^{SO}_*[1/2] = \mathbb{Z}[1/2, x_4, x_8, x_{12}, \ldots]
$$</code>
If I remember correctly, this (and the answers to many bordism-related questions) can be found in Stong's "Notes on cobordism theory".</p>
http://mathoverflow.net/questions/26655/oriented-cobordism-rings/26678#26678Answer by Thorny for Oriented Cobordism RingsThorny2010-06-01T07:45:22Z2010-06-01T07:45:22Z<p>I would also recommend Wall's <a href="http://www.jstor.org/stable/1970136" rel="nofollow">Determination of the cobordism ring</a> as a more primary source, it also contains the fact that all torsion is of order 2.</p>