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We construct explicitly generators of projectable four-dimensional diffeomorphisms and triad rotation gauge symmetries in a model of vacuum gravity where the fundamental dynamical variables in a Palatini formulation are taken to be a lapse,…

General Relativity and Quantum Cosmology · Physics 2015-06-25 J. M. Pons , D. C. Salisbury , L. C. Shepley

We study foliations by curves on the three-dimensional projective space with no isolated singularities, which is equivalent to assuming that the conormal sheaf is locally free. We provide a classification of the topological and algebraic…

Algebraic Geometry · Mathematics 2023-06-19 Maurício Corrêa , Marcos Jardim , Simone Marchesi

We address the recently introduced notions of generalized principal bundle and generalized principal connection by keeping track of global geometric properties through local coordinate transformation laws. This approach leads us to…

Mathematical Physics · Physics 2026-05-05 Lorenzo Fatibene , Hartwig Winterroth

In this paper, we establish a structure theorem for a smooth projective variety $X$ with semi-positive holomorphic sectional curvature. Our structure theorem contains the solution for Yau's conjecture and it can be regarded as a natural…

Differential Geometry · Mathematics 2018-11-13 Shin-ichi Matsumura

A finite extension of global fields $L/K$ satisfies the Hasse norm principle if any nonzero element of $K$ has the property that it is a norm locally if and only if it is a norm globally. In 1931, Hasse proved that any cyclic extension…

Number Theory · Mathematics 2024-10-16 Thomas Rüd , Alan Bu

Starting with the data of a curve of singularity types, we use the Legendre transform to construct weak geodesic rays in the space of locally bounded metrics on an ample line bundle L over a compact manifold. Using this we associate weak…

Algebraic Geometry · Mathematics 2013-07-17 Julius Ross , David Witt Nystrom

In this paper we study the flag curvature of a particular class of Finsler metrics called general $(\alpha,\beta)$-metrics, which are defined by a Riemannian metric $\alpha$ and a $1$-form $\beta$. The classification of such metrics with…

Differential Geometry · Mathematics 2015-02-06 Changtao Yu , Hongmei Zhu

Let $X$ be a smooth connected projective algebraic curve over an algebraically closed field, and let $S$ be a finite nonempty closed subset in $X$. We study deformations of $\overline{\mathbb F}_\ell$-sheaves. The universal deformation…

Algebraic Geometry · Mathematics 2019-05-22 Lei Fu

In the presence of a nontrivial dual Selmer group, certain global even deformation rings are shown to be finite and flat over $\mathbb{Z}_p$. Previously, flatness was only known in established cases of Langlands reciprocity in the odd…

Number Theory · Mathematics 2026-04-01 Peter Vang Uttenthal

Deep networks have recently been shown to be vulnerable to universal perturbations: there exist very small image-agnostic perturbations that cause most natural images to be misclassified by such classifiers. In this paper, we propose the…

Computer Vision and Pattern Recognition · Computer Science 2021-03-03 Seyed-Mohsen Moosavi-Dezfooli , Alhussein Fawzi , Omar Fawzi , Pascal Frossard , Stefano Soatto

We consider the problem of adversarial bandit convex optimization, that is, online learning over a sequence of arbitrary convex loss functions with only one function evaluation for each of them. While all previous works assume known and…

Machine Learning · Computer Science 2022-02-15 Haipeng Luo , Mengxiao Zhang , Peng Zhao

A foliation is of toric type when it has a combinatorial reduction of singularities. We show that every toric type foliation on (C3, 0), without saddle-nodes, has invariant surface. We extend the argument of Cano-Cerveau, done for the…

Algebraic Geometry · Mathematics 2020-05-19 Felipe Cano , Beatriz Molina-Samper

Overparametrization is a key factor in the absence of convexity to explain global convergence of gradient descent (GD) for neural networks. Beside the well studied lazy regime, infinite width (mean field) analysis has been developed for…

Neural and Evolutionary Computing · Computer Science 2023-02-07 Raphaël Barboni , Gabriel Peyré , François-Xavier Vialard

An arithmetical discrete plane is said to have critical connecting thickness if its thickness is equal to the infimum of the set of values that preserve its $2$-connectedness. This infimum thickness can be computed thanks to the fully…

Discrete Mathematics · Computer Science 2014-06-27 Valérie Berthé , Damien Jamet , Timo Jolivet , Xavier Provençal

Under a convexity assumption on the boundary we solve a local inverse problem, namely we show that the geodesic X-ray transform can be inverted locally in a stable manner; one even has a reconstruction formula. We also show that under an…

Differential Geometry · Mathematics 2012-10-09 Gunther Uhlmann , András Vasy

The projection operation is a critical component in a wide range of optimization algorithms, such as online gradient descent (OGD), for enforcing constraints and achieving optimal regret bounds. However, it suffers from computational…

Machine Learning · Computer Science 2024-06-04 Zihao Hu , Guanghui Wang , Jacob Abernethy

Supplementary comments about generalized Lie algebroids are presented and a new point of view over the construction of the Lie algebroid generalized tangent bundle of a (dual) vector bundle is introduced. Using the general theory of…

Differential Geometry · Mathematics 2014-11-03 E. Peyghan , C. M. Arcuş , L. Nourmohammadifar

In this paper we report numerically observed spontaneous vanishing of mean curvature on a developable cone made by pushing a thin elastic sheet into a circular container. We show that this feature is independent of thickness of the sheet,…

Soft Condensed Matter · Physics 2009-11-11 Tao Liang , Thomas A. Witten

This article re-examines Lawvere's abstract, category-theoretic proof of the fixed-point theorem whose contrapositive is a `universal' diagonal argument. The main result is that the necessary axioms for both the fixed-point theorem and the…

Category Theory · Mathematics 2024-08-07 David Michael Roberts

We prove the Kawamata-Viehweg vanishing theorem for a large class of divisors on surfaces in positive characteristic. By using this vanishing theorem, Reider-type theorems and extension theorems of morphisms for normal surfaces are…

Algebraic Geometry · Mathematics 2023-06-22 Makoto Enokizono