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seen Aug 26 at 7:11

Aug
25
revised Push forward of the structure sheaf along covering
added 28 characters in body
Aug
25
answered Push forward of the structure sheaf along covering
Aug
25
awarded  Nice Answer
Aug
24
comment Is T($S^2 \times S^1$) trivial?
Thanks for the explanation, Mike.
Aug
24
comment Is T($S^2 \times S^1$) trivial?
+1 for the answer and the interesting comment (in which I made acquaintance with the verb "futz"). Did you learn about these parallelizable products of spheres in Hirsch ? I did.
Aug
24
comment Is T($S^2 \times S^1$) trivial?
Dear @Ted: yes, I know the idea but you are equating a bundle on $S^2\times S^1$ with a bundle on $S^2$ in your isomorphism. That abuse of language may be confusing for a beginner. I encourage you to write a complete answer, with the suitable pull-backs explicitly displayed, and I will gladly upvote you (and Bates would probably accept your answer...) .
Aug
24
comment Compute principal divisor for a rational function on a curve
Dear Atlas, I have added a justification which might help you.
Aug
24
revised Compute principal divisor for a rational function on a curve
added 476 characters in body
Aug
24
comment Compute principal divisor for a rational function on a curve
OK, I'll post the answer to the new question.
Aug
24
answered Compute principal divisor for a rational function on a curve
Aug
24
comment Compute principal divisor for a rational function on a curve
Dear Atlas, the two questions are not identical: else how do you explain that you can solve one but not the other:-) Anyway, I'm am just explaining the rules of the game, since you are new to this site. I know you acted in good faith and bear you no grudge: welcome to this site, Atlas!
Aug
24
comment Compute principal divisor for a rational function on a curve
Dear Atlas, you should try not to change your questions so drastically: I had begun to write a solution to the former version, and my time has been wasted. You should have left the first question, solved it and added the new question in another post. I will not write an answer to your new question, knowing that you might change your mind in a few minutes. Alex Youcis's legitimate perplexity is also a consequence of your unfortunate modifications.
Aug
24
comment Compute principal divisor for a rational function on a curve
The correct homogeneization is $g=\frac{x-2z}{z}$, not what you wrote.
Aug
24
awarded  Enlightened
Aug
24
awarded  Nice Answer
Aug
20
comment Sheaf of sections vanishing at a point is $\Gamma(E) \otimes I_p$
Your notation is wrong: $\Gamma(E)$ denotes the vector space of global sections of $E$. You might denote the sheaf asociated to $E$ by $\mathcal E$, etc.
Aug
20
comment How can I verify the image and and the fibers of this map?
Dear Amitai, it is not true in general that the fibers of a submersion are diffeomorphic to one another.
Aug
20
comment When is a polynomial map proper?
Dear @zcn, you are quite right: sorry I missed that parenthetical remark at the beginning of the question. I have removed my unfair comment. I'll remove this comment too, as soon as you give me a signal that you have read it.
Aug
19
comment Morphism of schemes $f\colon X\to Y$ associated to a continuous map of the underlying spaces $|X|\to |Y|$
I like your idea of promotion from topology to algebraic geometry: hierarchy should be preserved, at least if you are at the upper echelon :-)
Aug
19
answered Morphism of schemes $f\colon X\to Y$ associated to a continuous map of the underlying spaces $|X|\to |Y|$