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7 votes
1 answer
428 views

A geometric characterization of smooth points of a complex algebraic variety

Let $X^m\subset \mathbb{C}^n$ be an irreducible $m$-dimensional complex algebraic subvariety. Let $\mathbb{C}^n$ be equipped with the standard Hermitian metric. Fix an arbitrary point $p\in X$. Let $...
asv's user avatar
  • 21.8k
7 votes
2 answers
593 views

Whitney stratification and affine grassmanian

Let $G$ a simply connected group over $\mathbb{C}$ and $Gr:=G(\mathbb{C}((t)))/G(\mathbb{C}[[t]])$ the affine grassmannian. By Cartan decomposition we have a partition of stratas indexed by $\lambda\...
prochet's user avatar
  • 3,472
7 votes
1 answer
884 views

Localization of vanishing cycles

Consider a regular holonomic D-module (or a perverse sheaf) $M$ on a smooth variety $X$. Let $f:X\to A^1$ be a polynomial (or holomorphic) function. Question: Is it true that the $\lambda \in A^1$ ...
AFK's user avatar
  • 7,527
6 votes
0 answers
96 views

forms on singular spaces that can be integrated on an LCI

I'd like to characterize rational $k$-forms on a singular scheme $X$ which can be integrated on any (real) bounded submanifold that is locally LCI in $X$ in a real sense (i.e., which is the real ...
Dmitry Vaintrob's user avatar
6 votes
0 answers
376 views

Topological Singularities in Affine Varieties

Let $X$ be an affine variety over $\mathbb{C}$. Let $x\in X$. If $x$ is non-singular, then $x$ is locally holomorphic (in the Euclidean topology). See here for a relevant MO post. By results of ...
Sean Lawton's user avatar
  • 8,529
5 votes
1 answer
263 views

Measuring contact between algebraic varieties

I have two regular surfaces in three space, both of which are given by an equation. I would like to measure the contact between the two surfaces using only their equations. Usually, one would find a ...
Fly by Night's user avatar
4 votes
1 answer
312 views

Kähler-Einstein metrics on singular varieties

Let $X$ be a normal projective variety with klt singularities with numerically trivial canonical divisor $K_X$. Does there always exist a Kähler-Einstein metric on $X$?
user avatar
3 votes
1 answer
609 views

Normal form for a holomorphic Morse function

Similarly to Morse lemma, a holomorphic Morse function can be written, near a critical point, as $W_1^2+W_2^2+...+W_n^2+C$ , for well chosen coordinates $W_1,W_2,...,W_n$. I want to cite this result ...
feng's user avatar
  • 31
2 votes
2 answers
935 views

Applications of Slope Stability

Ross and Thomas developed slope-stability of $(X,L)$ where $X$ is an $L$-polarised variety and $L$ is an ample line bundle, as an obstruction to K-stability of $(X,L)$. DISCLAIMER: (Forgive me if I ...
Jesus Martinez Garcia's user avatar
2 votes
1 answer
558 views

quotient singularities

Let $X$ be a relaively compact projective variety and has only quotient singularities then for any n-form $\Omega$ , $$\int_{X_{reg}}\Omega\wedge \bar \Omega$$ is bounded? what about the converse
pickasa's user avatar
  • 99
2 votes
1 answer
399 views

resolution for the du Val's $(A_3)$-singularity

For the $A_m$-singularity, it can be viewed as the singular part of $\mathbb{C}^2/\mathbb{Z}_m$. The action of $\mathbb{Z}_m$ on $\mathbb{C}^2$ is defined as following $$ \bar{1} \cdot (z,w) = (z e^{\...
Pan's user avatar
  • 167
2 votes
0 answers
510 views

Weil Petersson metric on moduli space of Calabi Yau manifolds

Let $f:(X,D)\to Y$ be a holomorphic fibre space where $D$ is divisor with conic singularities and let fibres $(X_s,D_s)$ are log Calabi-Yau pair .i.e $K_X+D$ is nummerically trivial, then we have ...
user avatar
1 vote
1 answer
93 views

Existence of meromorphic 2-forms over normal surface singularities

Let $(X,o)$ be an isolated normal surface singularity. Denote by $U:=X\backslash \{o\}$. I am looking for conditions on $(X,o)$ under which there exists a holomorphic section $\omega \in H^0(U, \Omega^...
Jana's user avatar
  • 2,032
0 votes
0 answers
121 views

Is any singularity a subgerm of $(\mathbb{C}^n, 0)$?

I am studying singularity theory. I have often come across, in the literature, the sentence which says "let $(X,0) \subset (\mathbb{C}^n,0)$ be a singularity". Here a singularity is a ...
Math1016's user avatar
  • 369
0 votes
0 answers
228 views

On Whitney's paper on real algebraic varieties

I had previously asked this question on math.stackexchange and did not receive an answer and so I decided to reword it and pose it here. This question is based on Whitney's paper titled "...
Coherent Sheaf's user avatar