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Hoot
  • Member for 9 years, 6 months
  • Last seen more than 8 years ago
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Lower bound on the difference of singular values
This doesn't look like algebraic geometry to me.
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Relatively concise English expositions of the proofs of the various Weil conjectures
I take it that the book of Freitag-Kiehl has been dismissed?
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Where can I find a proof of identity of $H^1(X,T_X)$ and a quotient by the jacobian?
$X$ is smooth and $d$ is the degree of $f$? Have you tried smashing the conormal and Euler short exact sequences against this?
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How are moduli stacks used?
I think I understand you somewhat better now. Mumford at least does a calculation that really seems to mean something to me.
awarded
 Fanatic
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Image of a Weil divisor (height 1 prime) under normalization map
Maybe $R$ is normal?
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depth of ideal in polynomial ring
Are you taking the depth with respect to $(x_1,\dots,x_n)$? The associated primes are homogeneous and finite in number. Doesn't that do it?
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Understanding an application of Riemann-Roch in an article
I think the OP's concerns begin with "it follows that..."
awarded
 Commentator
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How to prove the existence of divisorial Zariski decomposition?
Just a note: the book of Nakayama to which I think you are referring seems to be freely available from Project Euclid.
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Extending a prime divisor to a principal divisor
If you want to see a really baby version of this I think Ex. IV.1.9 in Hartshorne is good. Of course, you said you already knew how to do curves and there are many more assumptions there, but still.
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Construction of Dualizing sheaf
I take your point about $i^!$. I'm not sure that Hartshorne ever does this. Does this tag from the Stacks project help? I haven't actually looked at your lemma.
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Construction of Dualizing sheaf
What, exactly, are you asserting is bogus in Hartshorne's proof?
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Vanishing locus of a general section of a vector bundle.
I think this is Lemma 5.2 in "3264 and All That".
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Good introductory references on algebraic stacks?
It's probably worth pointing out that Olsson's book will be out soon.
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Need a reference/proof for computing the regularity of ideal of points in $\mathbb P^d$?
I guess it depends on what "compute" means. Does something like Corollary 4.7 in Eisenbud's book on syzygies help?
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General Reference for surface singularities
There is some good stuff in Chapters 3 and 4 (I think) of Badescu's book. There is also Lipman's classic paper.
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 Enthusiast
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Geometric meaning of conductor
You can find a relationship between the conductor ideal and the "adjoint ideal" in 9.3.51 of Lazarsfeld's Positivity.
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definition of "immersion" of schemes (without open or closed)
Often a synonym for "locally closed immersion", so a closed embedding into an open subscheme. (I feel like I've seen the opposite order but in Milne's setting it shouldn't matter.)
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