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.

168,695 papers · 148 categories

Trend · papers per month

72143215286 · Jun 202019922001200920172026
48 results for metrics comparison

The paper proves volume comparison theorems for metrics near stable Einstein and Ricci flat manifolds.

problem Investigating volume comparison theorems for metrics near stable Einstein and Ricci flat manifolds.
method Applying similar techniques to derive local rigidity theorems for strictly stable Ricci flat manifolds.
result Derives local rigidity theorems for strictly stable Ricci flat manifolds with respect to σ2-curvature.

Study metric learning from limited preference comparisons, showing how low-dimensional structure can still reveal metric information.

problem Learning metric from limited pairwise preference comparisons.
method Ideal point model, divide-and-conquer approach for low-dimensional structure.
result Metric can be jointly identified even with limited comparisons when items exhibit low-dimensional structure.

In this article, we investigate the volume comparison with respect to scalar curvature. In particular, we show volume comparison holds for small geodesic balls of metrics near a V-static metric. For closed manifold, we prove the volume comparison for metrics near a strictly stable Einstein metric. As applications, we g…

2016-09-28abs ↗pdf ↗

The paper proves geometric comparisons on metric measure spaces with integral Bakry-Émery Ricci tensor bounds.

problem Geometric comparisons on metric measure spaces with specific tensor bounds.
method Integral radial Bakry-Émery Ricci tensor bounds and potential function/gradient bounds.
result Diameter and eigenvalue estimates on smooth metric measure spaces.

We prove mean curvature and volume comparison estimates on smooth metric measure spaces when their integral Bakry-Émery Ricci tensor bounds, extending Wei-Wylie's comparison results to the integral case. We also apply comparison results to get diameter estimates, eigenvalue estimates and volume growth estimates on smoo…

2016-10-13abs ↗pdf ↗

We define a notion of renormalized volume of an asymptotically hyperbolic manifold. Moreover, we prove a sharp volume comparison theorem for metrics with scalar curvature at least -6. Finally, we show that the inequality is strict unless the metric is isometric to one of the Anti-deSitter-Schwarzschild metrics.

2013-05-28abs ↗pdf ↗

Study geometric and topological properties of Finsler manifolds with weighted Ricci curvature bounds.

problem Geometric and topological properties of Finsler metric measure manifolds with integral weighted Ricci curvature bounds.
method Establish Laplacian comparison theorem, volume comparison theorems, volume growth estimate, Gromov pre-compactness, local Dirichlet isoperimetric constant estimate.
result First Dirichlet eigenvalue estimate and gradient estimate for harmonic functions.

Learning high quality class representations from few examples is a key problem in metric-learning approaches to few-shot learning. To accomplish this, we introduce a novel architecture where class representations are conditioned for each few-shot trial based on a target image. We also deviate from traditional metric-le…

2018-02-12abs ↗pdf ↗

In this expository note, we present a transparent proof of Toponogov's theorem for Alexandrov spaces in the general case, not assuming local compactness of the underlying metric space. More precisely, we show that if M is a complete geodesic metric space such that the Alexandrov triangle comparisons for curvature great…

2012-07-16abs ↗pdf ↗

Revisits conformal metrics with finite Q-curvature, providing necessary and sufficient conditions.

problem Understanding conformal metrics with finite total Q-curvature.
method Introduces conformal mass and provides necessary and sufficient conditions for normality.
result Derives volume comparison theorems and proves a positive mass type theorem related to Q-curvature.

We define a new type of metric comparison similar to the comparison of Alexandrov. We show that it has strong connections to continuity of optimal transport between regular measures on a Riemannian manifold, in particular to the so called MTW condition introduced by Xi-Nan Ma, Neil Trudinger and Xu-Jia Wang.

2017-11-26abs ↗pdf ↗

We establish volume comparison results for balls in Riemannian manifolds with C1,1C^{1,1}-metrics with a lower bound on the Ricci tensor and for the evolution of spacelike, acausal, causally complete hypersurfaces with an upper bound on the mean curvature in spacetimes with C1,1C^{1,1}-metrics with a lower bound on the tim…

2015-07-31abs ↗pdf ↗

We consider machine learning in a comparison-based setting where we are given a set of points in a metric space, but we have no access to the actual distances between the points. Instead, we can only ask an oracle whether the distance between two points ii and jj is smaller than the distance between the points ii an…

2017-04-05abs ↗pdf ↗

New proposed models are often compared to state-of-the-art using statistical significance testing. Literature is scarce for classifier comparison using metrics other than accuracy. We present a survey of statistical methods that can be used for classifier comparison using precision, accounting for inter-precision corre…

2016-09-29abs ↗pdf ↗

Distance functions of metric spaces with lower curvature bound, by definition, enjoy various metric inequalities; triangle comparison, quadruple comparison and the inequality of Lang-Schroeder-Sturm. The purpose of this paper is to study the extremal cases of these inequalities and to prove rigidity results. The spaces…

2009-12-01abs ↗pdf ↗

The chapter reviews metrics for comparing curves, focusing on quotient elastic and square root velocity metrics.

problem Comparing and analyzing shapes of curves.
method Construction and theoretical properties of quotient elastic metrics, special case of square root velocity metric, numerical approaches for estimation.
result Simplified expression for the square root velocity metric distance.

Paper proves a sharp weighted Isoperimetric inequality for substatic manifolds.

problem Proving geometric results for substatic Riemannian manifolds.
method Comparison theory based on a newly discovered conformal connection.
result Sharp, weighted Isoperimetric inequality quantifying boundary minimization.

Learning from triplet comparison data has been extensively studied in the context of metric learning, where we want to learn a distance metric between two instances, and ordinal embedding, where we want to learn an embedding in an Euclidean space of the given instances that preserves the comparison order as well as pos…

2019-07-24abs ↗pdf ↗

The study examines stability and instability of Poincaré-Einstein metrics using Ricci flow.

problem Stability and instability of Poincaré-Einstein metrics.
method Variant of expander entropy for asymptotically hyperbolic manifolds, local positive mass theorem, volume comparison.
result Characterization of stability and instability in terms of local positive mass theorem and volume comparison.

On Kahler manifolds with Ricci curvature lower bound, assuming the real analyticity of the metric, we establish a sharp relative volume comparison theorem for small balls. The model spaces being compared to are complex space forms, i.e, Kahler manifolds with constant holomorphic sectional curvature. Moreover, we give a…

2011-08-22abs ↗pdf ↗

Uniform Laplace comparison for Kähler Ricci flow on Fano manifolds.

problem Proving convergence of Kähler-Ricci flows on Fano manifolds.
method Uniform integral Laplace comparison, Cheeger-Colding theory, and previous results.
result Direct proof of the Hamilton-Tian conjecture on convergence of Kähler-Ricci flows, modulo a codimension 4 singular set.

We prove explicit upper and lower bounds for the L1L^1-moment spectra for the Brownian motion exit time from extrinsic metric balls of submanifolds PmP^m in ambient Riemannian spaces NnN^{n}. We assume that PP and NN both have controlled radial curvatures (mean curvature and sectional curvature, respectively) as view…

2010-09-07abs ↗pdf ↗

This paper evaluates metrics for graph generative models, addressing common pitfalls.

problem Evaluating and comparing graph generative models effectively.
method Systematic evaluation of MMD, analysis of synthetic and real graphs, practical recommendations.
result MMD can be problematic; practical solutions are provided.

Paper proves optimal systolic inequality for manifolds with positive triRic curvature.

problem Optimal systolic inequality for manifolds with positive triRic curvature.
method Stable weighted kk-slicing, volume comparison theorem, and metric deformation.
result Proves an optimal systolic inequality and characterizes the equality case.

Global gradient estimates for Fisher-KPP equation on Finsler metric measure spaces.

problem Establishing gradient estimates for the Finslerian Fisher-KPP equation.
method Global gradient estimates on compact and noncompact Finsler metric measure spaces using the traditional CD(K,N)CD(K,N) condition and new comparison theorems.
result Global gradient estimates for positive solutions of the Finslerian Fisher-KPP equation.

Motivated by a classical comparison result of J. C. F. Sturm we introduce a curvature-dimension condition CD(k,N) for general metric measure spaces and variable lower curvature bound k. In the case of non-zero constant lower curvature our approach coincides with the celebrated condition that was proposed by K.-T. Sturm…

2015-06-10abs ↗pdf ↗

We study Gauss curvature for random Riemannian metrics on a compact surface, lying in a fixed conformal class; our questions are motivated by comparison geometry. Next, analogous questions are considered for the scalar curvature in dimension n>2n>2, and for the QQ-curvature of random Riemannian metrics.

2010-01-29abs ↗pdf ↗

Uniform comparison of hyperbolic ball volumes on universal cover.

problem Comparing hyperbolic ball volumes on universal cover.
method Proving a constant δ_n exists such that for any metric g on M, if the volume ratio is less than δ_n, the volume of hyperbolic balls is at least as large as in hyperbolic space.
result Every Riemannian metric g on M with a specific volume ratio satisfies the volume of hyperbolic balls on the universal cover is at least as large as in hyperbolic space.

On H-type sub-Riemannian manifolds we establish sub-Hessian and sub-Laplacian comparison theorems which are uniform for a family of approximating Riemannian metrics converging to the sub-Riemannian one. We also prove a sharp sub-Riemannian Bonnet-Myers theorem that extends to this general setting results previously pro…

2019-09-08abs ↗pdf ↗