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S. Carnahan's user avatar
S. Carnahan's user avatar
S. Carnahan's user avatar
S. Carnahan
Moderator
  • Member for 15 years, 2 months
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"A gentleman never chooses a basis."
I'm having trouble coming up with a sufficiently patriarchal argument. Does "these parts" refer to the pre-suffrage era?
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Examples of great mathematical writing
Oops, I guess I was supposed to submit a single piece. I'd say "Oeuvres de Serre" but it doesn't contain his books.
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does a line bundle always have a degree
Yeah, see Lemma 1.2 and its proof in section 4.1 in Hartshorne. Your divisor has to be effective to get h^0 positive, and if it has degree 0, then it is the zero divisor. I believe this extends to all proper varieties.
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Motivation for algebraic K-theory?
I'd like to emphasize that I'm not necessarily looking for holistic, coherent answers. Fragmentary brain dumps are also welcome (and may receive up-votes).
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Motivation for algebraic K-theory?
I used to spend a lot of time looking at the K-theory archive (www.math.uiuc.edu/K-theory/) but I have yet to find enlightenment.
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When and how is a group of order n isomorphic to a regular subgroup of equal order?
A group of permutations of a nonempty set is transitive if the set has one orbit, i.e., if for any pair of elements of the set, there is an element of the group taking one to the other.
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Are there interesting monoidal structures on representations of quantum affine algebras?
I don't really think ordinary tensor products are boring. I should change it to a more judgment-neutral word.
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How to attack this diophantine equation in 3 variables?
As far as I can tell, 31427 was chosen because it is the smallest number whose square is larger than 987654321. This covers all cases where a,b, and c are nonnegative. I would not be surprised if there were additional solutions where a and b have opposite signs.
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What is the universal property of associated graded?
Minor corrections: the morphism is of filtered vector spaces, and the degrees of the associated graded map should be shifted up.
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Functions on hyperbolic space and modular curves
removed weight 0 error, added part d
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How to attack this diophantine equation in 3 variables?
The link you provided has solutions on it, together with code for a brute force search. Are you asking for a general algorithm to find integer points on cubic surfaces?