Glen M Wilson
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Registered User
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May 4 |
awarded | ● Nice Question |
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May 3 |
comment |
Does the paper “On the cobordism ring $\Omega_*$ and a complex analogue II” exist? Awesome! Thank you very much. |
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May 3 |
asked | Does the paper “On the cobordism ring $\Omega_*$ and a complex analogue II” exist? |
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Apr 21 |
comment |
Examples of applications of the Freyd-Mitchell embedding theorem. Take $\alpha \in \pi_i^s$, $\beta \in \pi_j^s$. THey can be represented by maps $\alph : S^{i+j+k} \rightarrow S^{j+k}$ and $\beta : S^{j+k} \rightarrow S^k$ so that the composition is defined $\alpha \circ \beta : S^{i+j+k} \rightarrow S^k$ which then determines an element of $\pi_{i+j}^s$. From a more general perspective $\pi_*^s = \mathbb{S}^*(pt)$---the cohomology of a point where $\mathbb{S}$ is the sphere spectrum. The sphere spectrum is a ring spectrum so cohomology groups have a product structure. |
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Dec 29 |
answered | Math for a cake |
