4. Definitions of higher singularities and related invariants
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Problem 4.1.
[Shend Zhjeqi] Is there an analytic characterization of the minimal exponent in the lci case? -
Problem 4.2.
[Alexandra Viktorova] What is the correct notion of higher DB singularities in the symplectic case? -
Problem 4.3.
[Radu Laza and Sándor Kovács] What is the a definition of m-Du Bois singularities satisfying:- 0-Du Bois = Du Bois;
- m-Du Bois $\Rightarrow$ (m-1)-Du Bois;
- $R^i f_* \Omega_{X/S}^m$ is locally free, and compatible with base change for any flat family $f: X \rightarrow S$ with pre-m-Du Bois fibers.
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Remark. [Bradley Dirks] Can we define it if $\mathbb{Q}_X[\dim X]$ is perverse?
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Problem 4.4.
[Brad Dirks] Is there a notion of minimal exponent in the non-lci case related to higher singularities? This requires p-Du Bois $\Rightarrow$ (p-1)-rational.
Is there an invariant characterizing rational singularities?
Cite this as: AimPL: Higher Du Bois and higher rational singularities, available at http://aimpl.org/higherdubois.