arXiv research

Study of flip graphs and their automorphism groups for infinite-type surfaces.

Flip symmetry on knot diagrams affects Khovanov homology.

Study quasisymmetric maps on hyperbolic plane boundaries.

We prove that every injective simplicial map $\mathcal{F}(S) \to \mathcal{F}(S')$ between flip graphs is induced by a subsurface inclusion $S\to S'$, except in finitely many cases. This extends a result of Korkmaz--Papadopoulos which asserts that every automorphism of the flip graph of a surface without boundary is ind…

Geodesics count exponentially between triangulations of surfaces with enough topology.

The flip graph and arc complex of a surface are shown to have finite rigidity.

This paper is about the geometry of flip-graphs associated to triangulations of surfaces. More precisely, we consider a topological surface with a privileged boundary curve and study the spaces of its triangulations with n vertices on the boundary curve. The surfaces we consider topologically fill this boundary curve s…

The space of topological decompositions into triangulations of a surface has a natural graph structure where two triangulations share an edge if they are related by a so-called flip. This space is a sort of combinatorial Teichmüller space and is quasi-isometric to the underlying mapping class group. We study this space…

The study classifies tilings of the sphere by congruent quadrilaterals.

Study flip graphs for surfaces of infinite type, finding uncountably many connected components.

This article is about the graph genus of certain well studied graphs in surface theory: the curve, pants and flip graphs. We study both the genus of these graphs and the genus of their quotients by the mapping class group. The full graphs, except for in some low complexity cases, all have infinite genus. The curve grap…

Finite subgraphs in flip graphs ensure unique surface embeddings.

Study shows flipping a small subset of labels can severely damage machine learning models.

Connected flip graphs for triangulations on hyperbolic surfaces.

Study of skateboard flips as continuous curves in $SO(3)$ group.

Neural networks have been criticized for their lack of easy interpretation, which undermines confidence in their use for important applications. Here, we introduce a novel technique, interpreting a trained neural network by investigating its flip points. A flip point is any point that lies on the boundary between two o…

An R_2-move is a homotopy of wrinkled fibrations which deforms images of indefinite fold singularities like Reidemeister move of type II. Variants of this move are contained in several important deformations of wrinkled fibrations, flip and slip for example. In this paper, we first investigate how monodromies are chang…

Efficiently poisons offline RLHF models by flipping preference labels.

New examples show flip distance and polyhedron triangulation numbers differ, with ratio close to 3/2.

The paper calculates ranks and bounds for Stiefel manifolds over different fields.

We prove that for a given flat surface with conical singularities, any pair of geometric triangulations can be connected by a chain of flips.

The paper bounds distances and transformations between pants decompositions and triangulations on surfaces.

We introduce a notion of cross-flips: local moves that transform a balanced (i.e., properly $(d+1)$-colored) triangulation of a combinatorial $d$-manifold into another balanced triangulation. These moves form a natural analog of bistellar flips (also known as Pachner moves). Specifically, we establish the following the…

In this paper, we investigate a family of graphs associated to collections of arcs on surfaces. These {\it multiarc graphs} naturally interpolate between arc graphs and flip graphs, both well studied objects in low dimensional geometry and topology. We show a number of rigidity results, namely showing that, under certa…

Identifies minimal training subset to flip a prediction.

In this paper, we use reinforcement learning to find effective decoding strategies for binary linear codes. We start by reviewing several iterative decoding algorithms that involve a decision-making process at each step, including bit-flipping (BF) decoding, residual belief propagation, and anchor decoding. We then ill…

In order to model volatile real-world network behavior, we analyze phase-flipping dynamical scale-free network in which nodes and links fail and recover. We investigate how stochasticity in a parameter governing the recovery process affects phase-flipping dynamics, and find the probability that no more than q% of nodes…

Let $Σ$ be a compact surface. We prove that the set of surface cubications modulo flips, up to isotopy, is in one-to-one correspondence with $\Z/2\Z\oplus H_1(Σ,\Z/2\Z)$.

We use flip points to explain and audit deep learning models, revealing decision boundaries and improving model performance.

A new surgery formula for knot lattice homology.

Study finds flipped classrooms improve student self-concept, enjoyment, but not exam scores.

We discuss the geometry of the c-map from projective special Kähler to quaternionic Kähler manifolds using the twist construction to provide a global approach to Hitchin's description. As found by Alexandrov et al. and Alekseevsky et al. this is related to the quaternionic flip of Haydys. We prove uniqueness statements…

We study flip-graphs of triangulations on topological surfaces where distance is measured by counting the number of necessary flip operations between two triangulations. We focus on surfaces of positive genus $g$ with a single boundary curve and $n$ marked points on this curve; we consider triangulations up to homeomor…

Using existing technology, we prove a Masur-Minsky style distance formula for flip- graph distance between two triangulations, expressed as a sum of the distances of the projections of these triangulations into arc graphs of the suitable subsurfaces of S.

We investigate a type of distance between triangulations on finite type surfaces where one moves between triangulations by performing simultaneous flips. We consider triangulations up to homeomorphism and our main results are upper bounds on distance between triangulations that only depend on the topology of the surfac…

Deep Partition Aggregation defends against poisoning attacks with provable certificates.

In this paper we develop a Morse-like theory in order to decompose birational maps and morphisms of smooth projective varieties defined over a field of characteristic zero into more elementary steps which are locally étale isomorphic to equivariant flips, blow-ups and blow-downs of toric varieties. A crucial role in th…

The paper solves pentagon equations using triangulations and edge transformations.

New method makes machine learning models robust to label flipping attacks.

We explore several families of flip-graphs, all related to polygons or punctured polygons. In particular, we consider the topological flip-graphs of once-punctured polygons which, in turn, contain all possible geometric flip-graphs of polygons with a marked point as embedded sub-graphs. Our main focus is on the geometr…

A musical instrument based on moduli spaces lets users hear geometric concepts.

Unified routing and arbitrage with concave continuation.

Many machine learning systems rely on data collected in the wild from untrusted sources, exposing the learning algorithms to data poisoning. Attackers can inject malicious data in the training dataset to subvert the learning process, compromising the performance of the algorithm producing errors in a targeted or an ind…

Proof of existence and uniqueness of weighted Voronoi-Delaunay on polyhedral surfaces.

New duality found between harmonic maps and self-dual solutions.

The study examines flip-graphs of non-orientable surfaces and their diameters.

FlipOut prunes neural networks by flipping weights' signs, achieving high sparsity.

A natural generalization of interval exchange maps are linear involutions, first introduced by Danthony and Nogueira. Recurrent train tracks with a single switch which we call non-classical interval exchanges, form a subclass of linear involutions without flips. They are analogs of classical interval exchanges, and are…