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Related papers: Singularities in any Characteristic

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We describe combinatorial aspects of classical resolution of singularities that are free of characteristic and can be applied to singular foliations and vector fields as well as to functions and varieties. In particular, we give a…

Algebraic Geometry · Mathematics 2018-08-20 Beatriz Molina-Samper

We develop the contact singularity theory for singularly-perturbed (or `slow-fast') vector fields of the general form $z' = H(z,\varepsilon)$, $z\in\mathbb{R}^n$ and $\varepsilon\ll 1$. Our main result is the derivation of computable,…

Dynamical Systems · Mathematics 2020-04-07 Ian Lizarraga , Robert Marangell , Martin Wechselberger

This paper generalizes existing methods to derive stronger bounds on the modality of hypersurface singularities. Our results demonstrate that each sudden jump in the extended Tjurina number necessarily increases the modality. Furthermore,…

Algebraic Geometry · Mathematics 2026-04-20 Hongrui Ma , Aoyu Ying , Huaiqing Zuo

In this survey article we introduce the notion of frontals, which provides a class of generalised submanifolds with singularities but with well-defined tangent spaces. We present a review of basic theory and known studies on frontals in…

Differential Geometry · Mathematics 2016-09-05 Goo Ishikawa

We give a simple proof of the splitting lemma in singularity theory, also known as generalized Morse lemma, for formal power series over arbitrary fields. Our proof for the uniqueness of the residual part in any characteristic is new and…

Algebraic Geometry · Mathematics 2025-11-18 Gert-Martin Greuel , Gerhard Pfister

A general strategy is given for the classification of graphs of rational surface singularities. For each maximal rational double point configuration we investigate the possible multiplicities in the fundamental cycle. We classify completely…

Algebraic Geometry · Mathematics 2013-06-20 Jan Stevens

We survey a number of results on the counting of points on hypersurfaces defined over finite fields. We also investigate when one can be guaranteed a non-singular point on a projective hypersurface and give a condition on the cardinality of…

Number Theory · Mathematics 2010-04-26 Jahan Zahid

We prove several new transversality results for formal CR maps between formal real hypersurfaces in complex space. Both cases of finite and infinite type hypersurfaces are tackled in this note.

Complex Variables · Mathematics 2015-06-26 Bernhard Lamel , Nordine Mir

The problem of resolution of singularities in positive characteristic can be reformulated as follows: Fix a hypersurface $X$, embedded in a smooth scheme, with points of multiplicity at most $n$. Let an $n$-sequence of transformations of…

Algebraic Geometry · Mathematics 2011-03-18 Angélica Benito , Orlando E. Villamayor

We study singularities and geometric properties of surfaces given by the singular loci of normal congruence of frontals with pure-frontal singular points. These surfaces consist of the normal ruled surface and focal surfaces of the initial…

Differential Geometry · Mathematics 2022-07-15 Samuel P. dos Santos , Keisuke Teramoto

Suppose that $f$ defines a singular, complex affine hypersurface. If the critical locus of $f$ is one-dimensional, we obtain new general bounds on the ranks of the homology groups of the Milnor fiber of $f$. This result has an interesting…

Algebraic Geometry · Mathematics 2007-05-23 Lê Dũng Tráng , David B. Massey

The principles behind the sharp, singular structures in a crumpled sheet are well understood. Here we discuss more general ways of exploiting such sharp structures to control the shape of a sheet by deforming or forcing it elsewhere. Often,…

Soft Condensed Matter · Physics 2025-03-24 Thomas A. Witten , Anna Movsheva

We study singular hypersurfaces in tensor multi-scalar theories of gravity. We derive in a distributional and then in an intrinsic way, the general equations of junction valid for all types of hypersurfaces, in particular for lightlike…

General Relativity and Quantum Cosmology · Physics 2011-05-12 C. Barrabes , G. F. Bressange

In this paper we classify the unimodal isolated complete intersection singularities in arbitrary characteristic under contact equivalence. The classification over $\mathbb{C}$ has already done by A. Dimca and C.G. Gibson. We continue and…

Algebraic Geometry · Mathematics 2026-04-20 Hongrui Ma , Stephen S. -T. Yau , Huaiqing Zuo

We investigate the geometry of holomorphic curves and complex surfaces from the perspective of singularity theory. We show that, with a suitable choice of a complex bilinear symmetric form, the families of functions and mappings that…

Differential Geometry · Mathematics 2025-12-23 Amanda Dias Falqueto , Farid Tari

We present herewith certain thoughts on the important subject of nowadays physics, pertaining to the so-called ``singularities'', that emanated from looking at the theme in terms of ADG (: abstract differential geometry). Thus, according to…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Anastasios Mallios

Power series are introduced that are simultaneously convergent for all real and p-adic numbers. Our expansions are in some aspects similar to those of exponential, trigonometric, and hyperbolic functions. Starting from these series and…

Mathematical Physics · Physics 2011-07-19 Branko G. Dragovich

The concept of the maximal contact is the key in Hironaka's resolution theory. It treats local theory, and it is not effective in positive characteristics. This is the essential reason why Hironaka's theory treats only the case of…

Algebraic Geometry · Mathematics 2015-03-17 Tohsuke Urabe

The results of the renormalization group are commonly advertised as the existence of power law singularities near critical points. The classic predictions are often violated and logarithmic and exponential corrections are treated on a…

In this paper, we prove a similar result to the fundamental theorem of regular surfaces in classical differential geometry, which extends the classical theorem to the entire class of singular surfaces in Euclidean 3-space known as frontals.…

Differential Geometry · Mathematics 2019-10-08 Tito Alexandro Medina Tejeda