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6 votes
0 answers
564 views

Bogomolov–Miyaoka–Yau inequality for minimal varieties with intermediate Kodaira dimension $0<\kappa (X)<\dim X$

From the differential geometric proof of Yau and the algebraic proof of Miyaoka for minimal varieties of general type $\kappa (X)=\dim X$, we know that $$(-1)^nc_1^n(X)\leq (-1)^n\frac{2(n+1)}{n} c_1^...
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4 votes
0 answers
235 views

Some examples where the plurigenera are nonconstant, when the fibres have worse singularities than canonical

Let start with a definition Invariance of plurigenera: Choose $m$ large enough so that $mK_F$ has a non-zero global section for some fibre $F$. For any fibre $F$, we have $K_F = K_{X/D}~_{|F}$. So ...
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3 votes
0 answers
198 views

$L^2$ extension theorem

Is there an Ohsawa-Takagushi $L^2$-Extension theorem for Kahler manifolds? For projective varieties Siu-Paun proved: Let $\pi \colon X \to \mathbb D$ be a projective family of $n$-folds and $X_0$ be ...
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2 votes
0 answers
441 views

Moishezon projectivity criterion for Moishezon spaces with canonical singularites

A Moishezon manifold is projective if and only if it is Kähler. This is no longer true for a singular Moishezon space. Moishezon proved a projectivity criterion for Moishezon spaces with isolated ...
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1 vote
1 answer
417 views

Central fibre singularities

Let $f:X\to Y $ be a proper surjective holomorphic fibre space where $X,Y $ are projective varieties. If the central fibre $X_0$ has at worst log terminal singularities, then can we say that all ...
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1 vote
0 answers
523 views

Quasi-projectivity of the moduli space of Kahler-Einstein Fano varities and vanishing Lelong number

Chi Li, Xiaowei Wang, Chenyang Xu proved the Quasi-projectivity of the moduli space of smooth Kahler-Einstein Fano manifolds. My question is about when central fibre $X_0$ along Kahler-Einstein Fano ...
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0 votes
1 answer
406 views

$m$-th root of holomorphic section of direct image of relative line bundle

Question edited after the answer of Sándor Kovács: Let $f:X\to B$ be a holomorphic fibre space of smooth projective varieties which $f$ is relatively semi-ample and take $\mu$ as $m$-th root of ...
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0 votes
0 answers
152 views

$C^\infty$-curvature of Kawamata's singular hermitian metric

Let $X,Y$ are two projective varieties and $f:X\to Y$ is an Iitaka fibration. Consider the following singular hermitian metric $$h(\sigma,\sigma)=\left(\int_{X_y}|\sigma|^{\frac{2}{m!}}\right)^{m!}$$ ...
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