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8 votes
0 answers
277 views

Cohomology of complex manifold vs cohomology of its complex submanifold

Let $X$ be a smooth complex analytic manifold. Let $Z\subset X$ be a smooth compact analytic submanifold. Let $A$ be a holomorphic vector bundle over $X$. Assume that $$H^i(Z, A|_Z)=0 \mbox{ for any } ...
asv's user avatar
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6 votes
0 answers
200 views

Reference request: Automorphisms of $\mathbb C\{x,y\}$ which preserve the equation of the cusp, $x^3 - y^2$

In my research I encountered automorphisms of the ring of convergent power series $$\varphi: \mathbb C\{x,y\} \to \mathbb C\{x,y\},$$ which preserve $f = x^3 - y^2$, i.e. $\varphi(f) = f$. I'm ...
red_trumpet's user avatar
  • 1,286
6 votes
0 answers
360 views

Flat base change in the complex analytic setting

On page 255 of Hartshorne's Algebraic Geometry, it is shown that "cohomology commutes with flat base extension": Proposition III.9.3: Let $f : X \to Y$ be a separated morphism of finite type of ...
tomberg's user avatar
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3 votes
0 answers
135 views

Asymptotic Expansion of Seiberg-Witten Differential?

Nekrasov & Okounkov proved (https://arxiv.org/pdf/hep-th/0306238.pdf) that the Seiberg-Witten prepotential can be given by \begin{equation} \mathcal{F}(\mathbf{a},\Lambda) = \lim_{\hbar\rightarrow ...
user113988's user avatar
3 votes
0 answers
482 views

Possible automorphisms of a Jacobian

If we consider automorphisms of the Jacobian $J(C)$ of a curve $C$ which are compatible with the canonical polarization, we can describe this automorphism group in terms of $\text{Aut }C$ (see ``On ...
modnar's user avatar
  • 521
2 votes
0 answers
154 views

Algebra of meromorphic functions on a Riemann surface

Let $C$ be compact Riemann surface of high genus. Let $p$ be a general point on $C$ and $z$ a local coordinate around $p$. Given a meromorphic function on $C$, regular outside $p$, we can look at its ...
Giulio's user avatar
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2 votes
0 answers
320 views

Solution to algebraic equations over $\mathbb{C}$ and $\mathbb{C}[x]$

$t^n=a$, we get one solution to the equation: $$t=e^{\frac{1}{n}\int^a_1 \frac{1}{x}}$$ generalizing this result by replacing the exponential with an elliptic modular function and the integral with ...
XL _At_Here_There's user avatar
2 votes
0 answers
179 views

Questions about transformation or integral transformation

I have asked several mathematicians about the following questions,but all of them think they are good questions,but can not give a complete answer.Now I have to come here to ask mathematicians all ...
XL _At_Here_There's user avatar
2 votes
0 answers
215 views

ALE Kähler manifolds are birational to deformations of $\mathbb{C}^n/G$.

I am reading Dominic Joyce's book 'Compact Manifolds with Special Holonomy' and I am struggling to understand a remark he makes at the end of chapter 8. The assertion is (I think) the following: ...
oydeis's user avatar
  • 21
1 vote
0 answers
217 views

Homeomorphism of fibers of holomorphic maps

EDIT (after the comment by Jason Starr): Let $X$ be a complex algebraic (or, more generally, analytic) variety, possibly singular and non-compact. Let $f\colon X\to D^*$ be a proper algebraic morphism ...
asv's user avatar
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1 vote
0 answers
237 views

Proper monomorphisms in complex analytic spaces

In the algebraic geometry of schemes, we know that monomorphisms which are universally closed (= every pullback is a closed map) and of finite type are closed immersions. See Gortz, Wedhorn "Algebraic ...
Onion Dip Carlip's user avatar
1 vote
0 answers
156 views

Exactness of the relative de Rham complex restricted to subschemes

I think that the statement below about relative de Rham complex is true (am I wrong?) If it is the case, a reference would be very helpful. (I admit that the statement sounds somewhat technical and ...
asv's user avatar
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1 vote
0 answers
436 views

A question related to the Grauert semi-continuity theorem

Let $f\colon X\to Y$ be a proper holomorphic map of complex analytic manifolds. Assume $f$ to be submersive for simplicity, but probably it is not important. Let $\mathcal{F}$ be a coherent sheaf on $...
asv's user avatar
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