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.

168,694 papers · 148 categories

Trend · papers per month

95191286381 · May 202619922001200920172026
48 results for local smoothness

In this paper we aim for a generalisation of the Steenrod Approximation Theorem from, concerning a smoothing procedure for sections in smooth locally trivial bundles. The generalisation is that we consider locally trivial smooth bundles with a possibly infinite-dimensional typical fibre. The main result states that a c…

2006-10-07abs ↗pdf ↗

Local smoothing of metrics with small curvature, removing Ricci curvature condition.

problem Establishing local smoothing of metrics with curvature concentration.
method Local mollification, removing Ricci curvature condition, Sobolev constants and volume growth.
result Compactness of manifolds with small curvature concentration under Ahlfors regularity and Sobolev constant.

Study on diffeologies on locally convex spaces and smooth multiplication of distributions.

problem Geometric characterization and smoothness of distribution multiplication.
method Investigation of canonical and cc^\infty-diffeologies on locally convex spaces, proving geometric characterizations, and comparing diffeologies.
result Established a framework for nonlinear distribution theory beyond manifolds, realizing microlocally multipliable distributions as a diffeological colimit.

Motivated by the definition of the smooth manifold structure on a suitable mapping space, we consider the general problem of how to transfer local properties from a smooth space to an associated mapping space. This leads to the notion of smoothly local properties. In realising the definition of a local property at a pa…

2013-01-23abs ↗pdf ↗

Local minimizers are convex and close to Wulff shapes.

problem Finding local minimizers in anisotropic isoperimetric problems.
method Showed local minimizers are geodesically convex and small smooth perturbations of tangent Wulff shapes.
result Local minimizers are quantitatively close to Wulff shapes.

Non-parametric estimation of a multivariate density estimation is tackled via a method which combines traditional local smoothing with a form of global smoothing but without imposing a rigid structure. Simulation work delivers encouraging indications on the effectiveness of the method. An application to density-based c…

2016-10-07abs ↗pdf ↗

We study diffeologies on locally convex spaces and their application to smooth multiplication of distributions.

problem Constructing smooth multiplication of distributions on locally convex spaces.
method Using diffeological colimits and wavefront-set criterion.
result Proving smooth multiplication of microlocally multipliable distributions.

Stochastic gradient methods are dominant in nonconvex optimization especially for deep models but have low asymptotical convergence due to the fixed smoothness. To address this problem, we propose a simple yet effective method for improving stochastic gradient methods named predictive local smoothness (PLS). First, we …

2018-05-23abs ↗pdf ↗

In this work we prove that every locally symmetric smooth submanifold gives rise to a naturally defined smooth submanifold of the space of symmetric matrices, called spectral manifold, consisting of all matrices whose ordered vector of eigenvalues belongs to the locally symmetric manifold. We also present an explicit f…

2012-12-17abs ↗pdf ↗

In this work we prove the fact that, for a short time, it is possible to construct a smooth parametrized family of isometric embeddings of an arbitrary smooth parametrized family of Riemannian metrics on a smooth closed manifold into an Euclidean space. In order to prove this statement we work out stability estimates w…

2017-12-07abs ↗pdf ↗

Random forests are a powerful method for non-parametric regression, but are limited in their ability to fit smooth signals, and can show poor predictive performance in the presence of strong, smooth effects. Taking the perspective of random forests as an adaptive kernel method, we pair the forest kernel with a local li…

2018-07-30abs ↗pdf ↗

New cohomology theory reveals Q/Z\mathbb{Q}/\mathbb{Z} in group homology.

problem Understanding torsion in group homology of diffeomorphism groups.
method Introduced configured group cohomology, yielding explicit R/Z\R/\Z-valued 3-cocycles.
result Found a subgroup isomorphic to $\Q/\Z$ in the third group homology of certain diffeomorphism groups.

Proves local bi-integrability of bi-Hamiltonian systems on real smooth manifolds.

problem Proving local bi-integrability of bi-Hamiltonian systems on real smooth manifolds.
method Proves bi-integrability by constructing a complete set of functions in bi-involution and showing differentials can realize any bi-Lagrangian subspace.
result Bi-Hamiltonian systems are locally bi-integrable on real smooth manifolds.

In this note we prove that the level-set flow of the topologist's sine curve is a smooth closed curve. In previous work it was shown by the second author that under level-set flow, a locally-connected set in the plane evolves to be smooth, either as a curve or as a positive area region bounded by smooth curves. Here we…

2016-01-11abs ↗pdf ↗

FedProx algorithm improved for non-smooth and heterogeneous data.

problem Theoretical understanding of FedProx for non-convex federated optimization.
method Local dissimilarity invariant convergence theory through algorithmic stability.
result Convergence guarantees for non-smooth FL problems and minibatch size.

The paper proves weaker conditions for global smoothings of special Lagrangian submanifolds with conical singularities.

problem Conditions for global smoothings of special Lagrangian submanifolds with isolated conical singularities.
method Proof of weaker conditions for global smoothings.
result Global smoothings are possible under weaker hypotheses than previously known.

We prove the local existence of unique smooth solutions of the Donaldson geometric flow on the space of symplectic forms on a closed smooth four-manifold, representing a fixed cohomology class. It is a semiflow on the Besov space B21,p(M,Λ2)B^{1,p}_2(M, Λ^2) for p>4p > 4. The Donaldson geometric flow was introduced by Simon Dona…

2015-12-31abs ↗pdf ↗

New subharmonicity concept proves conjecture on Riemannian manifolds.

problem Proving positivity of solutions to a specific PDE on Riemannian manifolds.
method Introducing local λλ-shift defectivity and studying it on locally smoothing spaces.
result Proof of Braverman, Milatovic, Shubin conjecture on positivity of solutions.

Novel method for shape optimization of non-smooth PDEs.

problem Optimizing shapes governed by non-smooth PDEs.
method Functional variational approach and sensitivity analysis.
result Necessary conditions for locally optimal shapes.

We construct series of examples of exotic smooth structures on compact locally symmetric spaces of noncompact type. In particular, we obtain higher rank examples, which do not support Riemannian metric of nonpositive curvature. The examples are obtained by taking the connected sum with an exotic sphere. To detect the c…

2002-06-27abs ↗pdf ↗

We classify smooth locally free actions of the real affine group on closed orientable three-dimensional manifolds up to smooth conjugacy. As a corollary, there exists a non-homogeneous action when the manifold is the unit tangent bundle of a closed surface with a hyperbolic metric.

2007-02-27abs ↗pdf ↗

New method improves counterfactual distribution learning for high-dimensional outcomes.

problem Counterfactual distribution learning for high-dimensional outcomes with concentrated structure.
method Geometry-adaptive diffusion-guided smoothing estimators combining causal nuisance adjustment and local outcome geometry.
result Geometry-adaptive methods show steeper error decay in semi-synthetic experiments.

We prove that the essential smoothness of the gravitational metric at shock waves in GR, a PDE regularity issue for weak solutions of the Einstein equations, is determined by a geometrical condition which we introduce and name the {\it Riemann-flat condition}. The Riemann-flat condition determines whether or not the es…

2016-10-07abs ↗pdf ↗

The thesis clarifies when local updates outperform centralized methods in heterogeneous data environments.

problem Understanding when local updates are more effective than centralized or mini-batch methods in distributed optimization.
method Fine-grained consensus-error-based analysis framework, focusing on bounded second-order heterogeneity and third-order smoothness.
result Local updates outperform centralized or mini-batch methods under realistic models of data heterogeneity.

PF-LaCG removes the need for knowing smoothness and strong convexity parameters for locally accelerated CG.

problem Locally accelerated CG requires knowledge of smoothness and strong convexity parameters.
method Parameter-Free Locally Accelerated CG (PF-LaCG) algorithm.
result PF-LaCG achieves local acceleration without requiring knowledge of smoothness and strong convexity parameters.

Taking an elementary and straightforward approach, we develop the concept of a regular value for a smooth map f: O -> P between smooth orbifolds O and P. We show that Sard's theorem holds and that the inverse image of a regular value is a smooth full suborbifold of O. We also study some constraints that the existence o…

2012-05-05abs ↗pdf ↗

This is a survey on known results and open problems about Smooth and PL-Rigidity Problem for negatively curved locally symmetric spaces. We also review some developments about studying the basic topological properties of the space of negatively curved Riemannian metrics and the Teichmuller space of negatively curved me…

2015-10-11abs ↗pdf ↗