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We make a detailed study of various (quadratic and linear) Morse-Bott trace functions on the orthogonal groups $O(n)$. We describe the critical loci of the quadratic trace function Tr$(AXBX^T)$ and determine their indices via perfect…

Geometric Topology · Mathematics 2022-07-27 H. Işıl Bozma , William D. Gillam , Ferit Öztürk

In the context of discrete Morse theory, we introduce Morse frames, which are maps that associate a set of critical simplexes to all simplexes. The main example of Morse frames are the Morse references. In particular, these Morse references…

Discrete Mathematics · Computer Science 2026-03-30 Gilles Bertrand , Laurent Najman

Two simple observations are made: (1) If the normal function associated to a Hodge class has a zero locus of positive dimension, then it has a singularity. (2) The intersection cohomology of the dual variety contains the cohomology of the…

Algebraic Geometry · Mathematics 2009-04-02 Christian Schnell

We study the counting function of rational approximations with given bounds on the denominator and satisfying the critical Dirichlet exponent on the sphere $S^d$, $d\geq 3$. We give an effective estimate for this counting function, with an…

Number Theory · Mathematics 2025-12-23 Zouhair Ouaggag

Morse functions are important objects and tools in understanding topologies of manifolds since the 20th century. Their classification has been natural and difficult problems, and surprisingly, this is recently developing. Since the 2010's,…

Geometric Topology · Mathematics 2024-11-28 Naoki Kitazawa

For a hypersurface defined by a complex analytic function, we obtain a chain complex of free abelian groups, with ranks given in terms of relative polar multiplicities, which has cohomology isomorphic to the reduced cohomology of the real…

Algebraic Geometry · Mathematics 2024-12-31 David B. Massey

A smooth function f in a neighbourhood of the unit sphere $S^{n - 1}$ is said to admit index $\lambda$ if it can be extended to a function F in the unit ball $B^n$ such that F has a unique critical point p and the Morse index of p is equal…

Differential Geometry · Mathematics 2021-08-17 Daniil Mamaev

In this work, we define a Morse function on SO(n) and show that this function is indeed a perfect Morse function.

Algebraic Topology · Mathematics 2015-07-13 Mehmet Solgun

A Morse 2-function is a generic smooth map from a smooth manifold to a surface. In the absence of definite folds (in which case we say that the Morse 2-function is indefinite), these are natural generalizations of broken (Lefschetz)…

Geometric Topology · Mathematics 2016-01-20 David T. Gay , Robion Kirby

Using an estimate on the number of critical points for a Morse-even function on the sphere $\mathbb S^m$, $m\ge1$, we prove a multiplicity result for orthogonal geodesic chords in Riemannian manifolds with boundary that are diffeomorphic to…

Dynamical Systems · Mathematics 2015-03-23 R. Giambò , F. Giannoni , P. Piccione

An explicit isomorphism between Morse homology and singular homology is constructed via the technique of pseudo-cycles. Given a Morse cycle as a formal sum of critical points of a Morse function, the unstable manifolds for the negative…

Geometric Topology · Mathematics 2007-05-23 Matthias Schwarz

The Morse-Smale complex of a function $f$ decomposes the sample space into cells where $f$ is increasing or decreasing. When applied to nonparametric density estimation and regression, it provides a way to represent, visualize, and compare…

Statistics Theory · Mathematics 2017-04-05 Yen-Chi Chen , Christopher R. Genovese , Larry Wasserman

In this work, we design a nearly linear time discrete Morse theory based algorithm for computing homology groups of 2-manifolds, thereby establishing the fact that computing homology groups of 2-manifolds is remarkably easy. Unlike previous…

Computational Geometry · Computer Science 2015-05-12 Abhishek Rathore

The shape of homogeneous, generic, smooth convex bodies as described by the Euclidean distance with nondegenerate critical points, measured from the center of mass represents a rather restricted class M_C of Morse-Smale functions on S^2.…

Differential Geometry · Mathematics 2015-12-01 Gábor Domokos , Zsolt Lángi , Tí mea Szabó

In this short note, we show that the distance function to any finite set $X\subset \mathbb{R}^n$ is a topological Morse function, regardless of whether $X$ is in general position. We also precisely characterize its topological critical…

Differential Geometry · Mathematics 2024-07-23 Charles Arnal

This is a note on the graphs of two smooth real-valued functions in the plane with no intersection and the natural map onto the region surrounded by them with the canonical projection to the line composed, yielding its Reeb space. The Reeb…

General Topology · Mathematics 2026-03-24 Naoki Kitazawa

We present symbolic and numerical methods for computing Poisson brackets on the spaces of measures with positive densities of the plane, the 2-torus, and the 2-sphere. We apply our methods to compute symplectic areas of finite regions for…

Symplectic Geometry · Mathematics 2022-02-15 J. C. Ruíz-Pantaleón , P. Suárez-Serrato

We give a new and constructive proof of the existence of a special class of univariate polynomials whose graphs have preassigned shapes. By definition, all the critical points of a Morse polynomial function are real and distinct and all its…

Algebraic Geometry · Mathematics 2021-04-06 Miruna-Stefana Sorea

Two-point correlation functions (2PCF) are widely used to characterize how points cluster in space. In this work, we study the problem of measuring the 2PCF over a large set of points, restricted to a subset satisfying a property of…

Computer Vision and Pattern Recognition · Computer Science 2026-04-08 Max Hamilton , Daniel Sheldon , Subhransu Maji

We introduce the notion of a Morse sequence, which provides a simple and effective approach to discrete Morse theory. A Morse sequence is a sequence composed solely of two elementary operations, that is, expansions (the inverse of a…

Computer Vision and Pattern Recognition · Computer Science 2024-02-13 Gilles Bertrand