English
Related papers

Related papers: Weakly--exceptional quotient singularities

200 papers

We study exceptional quotient singularities. In particular, we prove an exceptionality criterion in terms of the $\alpha$-invariant of Tian, and utilize it to classify four-dimensional and five-dimensional exceptional quotient…

Algebraic Geometry · Mathematics 2016-01-20 Ivan Cheltsov , Constantin Shramov

In this paper we apply Shokurov's inductive method to study terminal and canonical singularities. As an easy consequence of the Minimal Model Program we show that for any three-dimensional log terminal singularity there exists some special,…

Algebraic Geometry · Mathematics 2010-05-04 Yuri G. Prokhorov

We consider a class of quasiregular singularities characterized by points possessing two future-directed light cones and two past-directed light cones. Such singularities appear in the $1+1$ trousers spacetime and the Deutsch-Politzer…

General Relativity and Quantum Cosmology · Physics 2024-01-29 Justin C. Feng , Shinji Mukohyama , Sante Carloni

We study isolated quotient singularities by finite and linearly reductive group schemes (lrq singularities for short) and show that they satisfy many, but not all, of the known properties of finite quotient singularities in characteristic…

Algebraic Geometry · Mathematics 2025-12-17 Christian Liedtke , Gebhard Martin , Yuya Matsumoto

We define the class of weakly approximately divisible unital C*-algebras and show that this class is closed under direct sums, direct limits, any tensor product with any C*-algebra, and quotients. A nuclear C*-algebra is weakly…

Operator Algebras · Mathematics 2019-02-20 Don Hadwin , Weihua Li

We study the local behavior of weak solutions, with possible singularities, of nonlocal nonlinear equations. We first prove that sets of capacity zero are removable for weak solutions under certain integrability conditions. We then…

Analysis of PDEs · Mathematics 2025-07-09 Minhyun Kim , Se-Chan Lee

A weak type $(1,1)$ estimate is established for the first order $d$-commutator introduced by Christ and Journ\'e, in dimension $d\ge 2$.

Classical Analysis and ODEs · Mathematics 2016-04-20 Andreas Seeger

Gorenstein isolated quotient singularities of odd prime dimension are cyclic. In the case where the dimension is bigger than 1 and is not an odd prime number, then there exist Gorenstein isolated non-cyclic quotient singularities.

Commutative Algebra · Mathematics 2011-04-26 Kazuhiko Kurano , Shougo Nishi

The outcome of a weak quantum measurement conditioned to a subsequent postselection (a weak value protocol) can assume peculiar values. These results cannot be explained in terms of conditional probabilistic outcomes of projective…

Quantum Physics · Physics 2016-05-31 Alessandro Romito , Andrew N. Jordan , Yakir Aharonov , Yuval Gefen

We extend the results from the previous paper by A. Fr\"uhbis-Kr\"uger and the author [arXiv:1501.01915] to the vanishing topology of those singularities in the title. Studying the case of possibly non-isolated singularities in the Tjurina-…

Algebraic Geometry · Mathematics 2021-09-15 Matthias Zach

Covariant equations characterizing the strength of a singularity in spherical symmetry are derived and several models are investigated. The difference between central and non-central singularities is emphasised. A slight modification to the…

General Relativity and Quantum Cosmology · Physics 2016-08-25 Brien C. Nolan

In this paper we study $(\epsilon,\delta)$-lc singularites, i.e. $\epsilon$-lc singularities admitting a $\delta$-plt blow-up. We prove that $n$-dimensional $(\epsilon,\delta)$-lc singularities are bounded up to a deformation, and…

Algebraic Geometry · Mathematics 2019-03-19 Jingjun Han , Jihao Liu , Joaquín Moraga

Recently a new type of cosmological singularity has been postulated for infinite barotropic index $w$ in the equation of state $p=w \rho$ of the cosmological fluid, but vanishing pressure and density at the singular event. Apparently the…

General Relativity and Quantum Cosmology · Physics 2011-09-28 L. Fernández-Jambrina

A group is small if it has countably many complete $n$-types over the empty set for each natural number n. More generally, a group $G$ is weakly small if it has countably many complete 1-types over every finite subset of G. We show here…

Logic · Mathematics 2019-03-01 Cédric Milliet

We propose a definition of double categories whose composition of 1-cells is weak in both directions. Namely, a doubly weak double category is a double computad -- a structure with 2-cells of all possible double-categorical shapes --…

Category Theory · Mathematics 2026-05-25 Aaron David Fairbanks , Michael Shulman

We prove some uniqueness results for weak solutions to some classes of parabolic Dirichlet problems.

Analysis of PDEs · Mathematics 2014-01-30 F. Feo

The dual complex of a singularity is defined, up-to homotopy, using resolutions of singularities. In many cases, for instance for isolated singularities, we identify and study a "minimal" representative of the homotopy class that is well…

Algebraic Geometry · Mathematics 2014-03-18 Tommaso de Fernex , János Kollár , Chenyang Xu

For a large class of non smooth bounded domains, existence of a global weak solution of the 2D Euler equations, with bounded vorticity, was established by G\'erard-Varet and Lacave. In the case of sharp domains, the question of uniqueness…

Analysis of PDEs · Mathematics 2013-10-22 Christophe Lacave , Evelyne Miot , Chao Wang

Based on the Decay and Fission Conjecture, we provide a classification of unitary quivers whose 3d $\mathcal{N}=4$ Coulomb branches exhibit isolated singularities. This yields the complete list of isolated conical symplectic singularities…

High Energy Physics - Theory · Physics 2025-04-09 Antoine Bourget , Quentin Lamouret , Sinan Moura Soysüren , Marcus Sperling

This work presents a range of triangulated characterizations for important classes of singularities such as derived splinters, rational singularities, and Du Bois singularities. An invariant called 'level' in a triangulated category can be…

Algebraic Geometry · Mathematics 2025-03-05 Pat Lank , Sridhar Venkatesh