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0 votes
0 answers
66 views

Details of the proof of the inequality $ \int_{X}\left(2 r \mathrm{c}_{2}(E)-(r-1) \mathrm{c}_{1}^{2}(E)\right) \wedge \omega^{n-2} \geq 0.$

I'm trying to make sense of the following proof. Let $E$ be a holomorphic vector bundle of rank $r$ on a compact hermitian manifold $(X, g)$. If $E$ admits an Hermite-Einstein structure then $$ \int_{...
Nikolai's user avatar
  • 103
0 votes
0 answers
126 views

Function of several complex variables with prescribed zeros

I accidentally stumbled upon a problem of complex analysis in several variables, and I have a hard time understanding what I read, it might be related to the Cousin II problem but I cannot say for ...
kaleidoscop's user avatar
  • 1,332
0 votes
0 answers
33 views

Contraction of an inclusion with respect to Kobayshi hyperbolic metric

Suppose that $X = \mathbb{C}^n - \Delta_X$ and $Y = \mathbb{C}^n - \Delta_Y$, where $\Delta_X$ and $\Delta_Y$ are unions of hyperplanes in $\mathbb{C}^n$ such that $\Delta_Y \subset \Delta_X$, $\...
A B's user avatar
  • 41
2 votes
1 answer
203 views

Prefactor $2\pi i$ for Tate-Hodge structure

A rather basic question. What was the original reason to consider the underlying $\mathbb{Z}$-module of the - as canonical object regarded - Tate-Hodge structure $\mathbb{Z}(1)$ to be given as $2 \pi ...
user267839's user avatar
  • 5,780
16 votes
0 answers
502 views

Gabriel's theorem for complex analytic spaces

Let $X,Y$ be noetherian schemes over $\mathbb{C}$. Then, it is known that $$ \text{Coh}(X) \simeq \text{Coh}(Y) \Rightarrow X \simeq Y, $$ by P. Gabriel(1962). Are there some results in the case of ...
Walterfield's user avatar
0 votes
0 answers
96 views

Principle of degeneration as precursor of Zariski's connectedness theorem (geometric intuition)

I have following question about so-called "principle of degeneration" in algebraic geometry (which in modern terms is an immediate consequence of Zariski's main theorem and goes in it's ...
user267839's user avatar
  • 5,780
0 votes
0 answers
160 views

“Holomorphic” bump function

I was wondering in what sense can I construct a holomorphic “bump function”? Now, of course we cannot really construct a holomorphic bump function in the usual sense, but I have a much rougher idea in ...
JustSomeGuy's user avatar
3 votes
0 answers
160 views

Action of complex Lie group on Dolbeault cohomology

Let $M$ be a compact complex manifold acted holomorphically by a complex Lie group $G$. Let $F$ be a holomorphic $G$-equivariant vector bundle over $M$. Consider the natural representation of $G$ in (...
asv's user avatar
  • 21.3k
3 votes
0 answers
192 views

An almost complex structure on $\Bbb S^n$ induces a cross product on $\Bbb R^{n+1}$

It is known that the only spheres that admit an almost complex structures are $\Bbb S^2$ and $\Bbb S^6$ (Borel and Serre, 1953). In particular, $\Bbb S^4$ cannot be given an almost complex structure (...
Random's user avatar
  • 1,097
4 votes
0 answers
114 views

Non-Kähler complex structure on $S^2 \times T^4$

Consider $M = S^2 \times T^4$. Then we can construct a non-Kähler complex structure as follows. Let $L$ be a line bundle over $\mathbb{P}^1$ such that there are two sections $s_1, s_2 \in H^0 (L)$ ...
Chicken feed's user avatar
1 vote
1 answer
92 views

Common holomorphic forms for two distinct complex structures

Let $S$ be a closed real surface having two complex structures $c_1$ and $c_2$ which are not biholomorphic (so $S$ is a Riemann surface with genus at least 1). Consider $\omega$ a 1-form on $S$ which ...
Dorian's user avatar
  • 331
2 votes
0 answers
132 views

Symmetric group-cocycle descends to symmetric product

Let $C$ be a complex curve with universal covering $\tilde{C}$ (which in my case is the upper half plane). Any group-cocylce $e \in H^1(\pi_1(C^n),H^0(\tilde{C}{}^n,\mathcal{O}^{\times}))$ defines a ...
KuSi's user avatar
  • 53
0 votes
1 answer
267 views

Universal covering of symmetric product

Let $C$ be a 1-dimensional complex manifold whose universal covering is provided by the half-plane $\mathcal{H}=\{z \in \mathbb{C} \mid \operatorname{Im}z>0\}$. The symmetric product $C^{(n)} = C^n ...
KuSi's user avatar
  • 53
1 vote
0 answers
148 views

Top cohomology of the canonical class of a compact non-Kähler manifold

Let $X$ be a complex compact manifold of complex dimension $n$. Let $K_X$ denote its canonical class. Is it true that the cohomology group $$H^n(X,K_X)$$ is one dimensional? Remark. If $X$ is Kähler ...
asv's user avatar
  • 21.3k
7 votes
1 answer
302 views

When $H^{p,q}_{\bar\partial}(X)$ can be seen as a subspace of $H^k(X,\mathbb C)$?

It is known that for a $\partial\bar\partial$-manifold $X$ (a compact complex manifold satisfies the $\partial\bar\partial$-lemma), the Bott-Chern cohomology $H_{BC}^{\bullet,\bullet}:=\frac{\ker \...
Tom's user avatar
  • 449

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