Timeline for What is the isomorphism from $\operatorname{Ext}^1_{T}(Y,X)$ to $\operatorname{Ext}_T(\mathbf{1},X\otimes Y^{\vee})$?
Current License: CC BY-SA 4.0
4 events
| when toggle format | what | by | license | comment | |
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| Apr 2, 2021 at 9:26 | comment | added | Leo Alonso | @BertramArnold Why don't you post your comment as an answer? It seems to address the question in full. | |
| Apr 2, 2021 at 9:11 | comment | added | Stabilo | Thank you very much @BertramArnold, this is what I was looking for. | |
| Apr 2, 2021 at 9:01 | comment | added | Bertram Arnold | The morphism is the composition of applying the functor $-\otimes Y^\vee$ and precomposition with the unit $\mathbf{1}\to Y\otimes Y^\vee$. Thus the middle term in the extension is the pullback $E\otimes Y^\vee\times_{Y \otimes Y^\vee} \mathbf{1}$. | |
| Apr 2, 2021 at 8:22 | history | asked | Stabilo | CC BY-SA 4.0 |