Research
On-device research index

arXiv research

A locally-built, LLM-digested index of recent arXiv papers in quant finance, geometry/topology, and statistical ML — keyword search served straight from SQLite on this machine.

169,042 papers · 148 categories

Trend · papers per month

12253749 · Jun 202019922001200920172026
48 results for combinatorial bijections

Paper explores algebraic, topological, and combinatorial properties of singular virtual braids.

problem Understanding singular virtual braids and their properties.
method Algebraic relations, topological and combinatorial bijections, presentations.
result A bijection between singular abstract braids and singular virtual braids, leading to a presentation of the singular pure virtual braid monoid.

Virtual braids are a combinatorial generalization of braids. We present abstract braids as equivalence classes of braid diagrams on a surface, joining two distinguished boundary components. They are identified up to isotopy, compatibility, stability and Reidemeister moves. We show that virtual braids are in a bijective…

2014-02-03abs ↗pdf ↗

The paper describes a stratification of a compactified Hurwitz space using combinatorial trees.

problem Describing the boundary stratification of a compactified Hurwitz space.
method Using decorated trees to describe the boundary strata and their containment relations.
result The boundary strata of the compactified Hurwitz space are in bijection with decorated trees, and containment is given by edge contraction.

The study broadens the concept of cyclic polytopes to Veronese polytopes.

problem Extending the framework of cyclic polytopes to a broader class of polytopes.
method Described facial structure and combinatorial characterisation of facets via σ-parity alternating sequences.
result Established a bijective correspondence between combinatorial types of Veronese polytopes and partitions of finite sets.

We study natural bases for two constructions of the irreducible representation of the symmetric group corresponding to [n,n,n][n,n,n]: the {\em reduced web} basis associated to Kuperberg's combinatorial description of the spider category; and the {\em left cell basis} for the left cell construction of Kazhdan and Lusztig. I…

2013-07-24abs ↗pdf ↗

CIFs replace single bijections with continuous families to avoid topological limitations.

problem Normalising flows struggle with targets with complex topologies.
method Propose Continuously Indexed Flows (CIFs) replacing single bijections with a continuous family.
result CIFs avoid topological limitations and perform better empirically.

K. Ding studied a class of Schubert varieties X_λin type A partial flag manifolds, corresponding to integer partitions λand in bijection with dominant permutations. He observed that the Schubert cell structure of X_λis indexed by maximal rook placements on the Ferrers board B_λ, and that the integral cohomology groups …

2004-03-31abs ↗pdf ↗

A bijection proves a polynomial volume for genus-0 hyperbolic surfaces with boundaries.

problem Proving the Weil-Petersson volume polynomial in boundary lengths for genus-0 surfaces.
method Generalizing a tree bijection to handle geodesic boundaries, extending spine construction.
result Explicit formula for three-point function in Weil-Petersson random surfaces.

We identify causal models with unobserved confounding using bijective generation mechanisms.

problem Identifying causal relationships with unobserved confounders.
method Establish counterfactual identifiability for BGMs and propose a learning method.
result Learned BGMs enable efficient counterfactual estimation.

Improved ANN-based Monte Carlo simulation for Higgs decay events.

problem Accurate simulation of Higgs boson decay events.
method Monte Carlo simulation using an Artificial Neural Network (ANN) with improved training algorithm.
result The ANN simulation of Higgs decay is within 0.7% of the true value and achieves 26% unweighting efficiency.

Given a pair of number fields with isomorphic rings of adeles, we construct bijections between objects associated to the pair. For instance we construct an isomorphism of Brauer groups that commutes with restriction. We additionally construct bijections between central simple algebras, maximal orders, various Galois co…

2015-05-18abs ↗pdf ↗

This paper constructs an algebra on a 3-torus with specific properties for fluid dynamics.

problem Constructing an algebraic structure on a 3-torus with specific properties.
method Combining combinatorial graded intersection algebra with Sullivan's and Lawrence-Sullivan-Ranade's subcomplexes.
result The construction of an algebra with specific properties on the 3-torus.

Study Alexander polynomials of special alternating links and generalize Fox's conjecture.

problem Distinguish special alternating links up to isotopy using polynomial invariants.
method Combinatorial and discrete geometric properties of Alexander polynomials of special alternating links.
result Generalized Alexander polynomials of special alternating links can be expressed in terms of volumes of root polytopes of unimodular matrices.

The classical Fundamental Theorem of Affine Geometry states that for n2n\geq 2, any bijection of nn-dimensional Euclidean space that maps lines to lines (as sets) is given by an affine map. We consider an analogous characterization of affine automorphisms for compact quotients, and establish it for tori: A bijection o…

2016-12-17abs ↗pdf ↗

Let XX be a topological space and f:XXf:X\to X a bijection. Let C(X,f){\mathcal C}(X,f) be a set of integers such that an integer nn is an element of C(X,f){\mathcal C}(X,f) if and only if the bijection fn:XXf^n:X\to X is continuous. A subset SS of the set of integers Z{\mathbb Z} is said to be realizable if there is a topologi…

2013-10-07abs ↗pdf ↗

We introduce an equivalence relation, called stable equivalence, on knot diagrams and closed curves on surfaces. We give bijections between the set of abstract knots, the set of virtual knots, and the set of the stable equivalence classes of knot diagrams on surfaces. Using these bijections, we define concordance and l…

2000-08-16abs ↗pdf ↗

We classify the torsion pairs in a tube category and show that they are in bijection with maximal rigid objects in the extension of the tube category containing the Pruefer and adic modules. We show that the annulus geometric model for the tube category can be extended to the larger category and interpret torsion pairs…

2011-12-28abs ↗pdf ↗

In the eighties Goldman discovered a Lie algebra structure on the vector space generated by the free homotopy classes of oriented curves on an oriented surface. The Lie bracket [a,b] is defined as the signed sum over the intersection points of a and b of the loop product of at the intersection points. If one of the cla…

2007-06-16abs ↗pdf ↗

Method flattens complex surfaces with consistent density and shape.

problem Shape deformations and local geometric distortions in density-equalizing maps for multiply-connected surfaces.
method Formulates density diffusion as a quasiconformal flow, solving an energy minimization problem involving the Beltrami coefficient to ensure bijectivity and control distortion.
result Achieves optimal parameterization of multiply-connected surfaces with bijective and controlled geometric distortions.

We prove a Lipschitz-Volume rigidity theorem in Alexandrov geometry, that is, if a 1-Lipschitz map f ⁣:X=⨿XYf\colon X=\amalg X_\ell\to Y between Alexandrov spaces preserves volume, then it is a path isometry and an isometry when restricted to the interior of XX. We furthermore characterize the metric structure on YY with re…

2011-10-25abs ↗pdf ↗

A bijection preserving horocycles/hypercycles is an isometry in hyperbolic plane.

problem Understanding transformations of constant curvature curves in hyperbolic geometry.
method Analyzing bijections that map horocycles to horocycles and hypercycles to hypercycles.
result Every abstract automorphism of geodesic/horocycles/hypercycles graphs is induced by an earthquake map/isometry.

Study on K3 surfaces' collapsing and special Kähler structures.

problem Understanding the structure of K3 surfaces' collapsing metrics.
method Analyzing M2\mathfrak{M}_2 and establishing connections to SKSs and Jacobian elliptic K3 surfaces.
result Established a bijection between integral singular SKSs on P1\mathbb{P}^1 and Jacobian elliptic K3 surfaces.