1
vote
0answers
68 views
complex Morse function on a four-manifold
If we have a complex Morse function on a complex four-manifold, $f: X\to \mathbb{C} $, can we tell from the function how the genus of inverse images $f^{-1}(z)$ (for regular values …
0
votes
1answer
146 views
Holomorphic objects associated with a compact complex manifold?
Good morning,
I'm just curious about the following. With a compact Kahler manifold, we can associate an Albanese torus. This helps us a lot study the manifold.
My question: Are …
8
votes
1answer
269 views
necessary and sufficient condition for existence of $SU(3)$-structure on 6-manifolds
Is there any necessary and sufficient condition for existence of $SU(3)$-structure on 6-manifolds $M$?
8
votes
1answer
256 views
Betti numbers of Proper nonprojective varieties
This is a question about pathologies.
Let $X/\mathbb{C}$ be an irreducible projective variety smooth over $\mathbb{C}$. Then, the singular cohomology groups $H^i(X, \mathbb{C})$ h …
2
votes
3answers
282 views
Two quetions on complex geometry.
I have two questions on complex geometry.
First one is that why the existence of almost complex structure on tangent bundle on real 2n-dimension manifold is a topological question …
0
votes
1answer
178 views
On a Hirzebruch surface.
I am trying to solve exercise in Huybrechts's book 'Complex geometry'
While solving problems, one problem kept me from going forward.
That is,
The surface $\Sigma_n=\mathbb{P}$ …
3
votes
2answers
169 views
When a Riemannian manifold is of Hessian Typ
When a Riemannian manifold is of Hessian Type (i.e., a Riemannian manifold which its metric is Hessian)
1
vote
1answer
127 views
Toroidal embedding
Its known ( see " The birational geometry of degenerations") that there exist a smooth one parameter family (i.e. total space is smooth) of two dimensional complex toris over unit …
8
votes
4answers
315 views
When does $Aut(X)=Bir(X)$ hold?
Let $X$ be a projective complex manifold. Under what condition do we have the equality $Aut(X)=Bir(X)$? Here $Aut(X)$ denotes the group of holomorphic automorphisms of $X$ and $Bir …
0
votes
0answers
56 views
Another fibration with a given singular fiber class.
Let $f:X\rightarrow C$ be a fibration of complex manifold over a smooth curve $C$. Let $D$ be an irreducible component of singular fibers. How can one prove that $X$ does not admit …
8
votes
3answers
595 views
Primitive Cohomology Useful?
In her book, after proving the hodge decomposition, Voisin spends time discussing primitive cohomology $H^r(X, \mathbb{C})_{prim} = \ker L^{n-r+1} \subset H^r(X, \mathbb{C})$ (wher …
8
votes
2answers
365 views
Torsion in cohomology of smooth manifolds
I've been interested in the possible (singular) cohomology groups of complex projective algebraic varieties, and there are lots of theorems that give various restrictions on these …
3
votes
1answer
442 views
recognizing Kahler manifolds of complex dimension n
Is there new classification of Kahler manifolds of complex dimension n and new results for necessary and sufficient conditions for a manifold being Kahler? I know if redactivity of …
1
vote
0answers
61 views
${\bar{\partial}}$-geometrically formal ?
A compact Riemannian manifold is called geometrically formal if the wedge product of two $d$-harmonic forms is $d$-harmonic. Are there any known results for when a non-Kahler com …
3
votes
1answer
400 views
Self-intersection and the normal bundle
Let $X/k$ be a surface nonsingular and proper over an algebraically closed field $k$. Let $C \subset X$ be a nonsingular curve. Then it is clear that the self-intersection $(C \cdo …

