Sharp inequality linking interior and boundary Yamabe invariants on specific manifolds.
problem Relating Yamabe invariants on asymptotically Poincare-Einstein manifolds.
method Established a sharp inequality using lower Ricci curvature bounds.
result Sharp inequality relating type II Yamabe invariant of the interior to the Yamabe invariant of the conformal infinity.
New proof shows inequality without restrictions.
problem Sharp inequality relating Yamabe invariants on Poincare-Einstein manifolds.
method New proof without restrictions.
result Sharp inequality holds without restrictions.
Sharp mapping properties and regularization for X-ray transform on disks of constant curvature.
problem Sharp mapping properties and regularization of X-ray transform.
method Derive functional relations and mapping properties using elliptic differential operators.
result Theoretical possibility of regularized inversions for X-ray transform.
New monotone Sharpe ratio measures investment performance.
problem Investment performance measurement.
method Introducing a new monotone Sharpe ratio and studying its properties.
result Established a connection with coherent risk measures and obtained an efficient representation.
The paper explores gaps in curvature-related metrics and rigidity.
problem Understanding gaps in curvature-related metrics and rigidity.
method Analyzes three types of gaps: spectral, metric-rigidity, and topological-rigidity.
result Proposes open problems in the field.
Paper derives a Pythagorean theorem for Sharpe ratio and validates a new method for portfolio optimization.
problem Optimizing investment risk with budget and return constraints.
method Replica analysis for portfolio optimization under non-specific probability distribution constraints.
result Derives a Pythagorean theorem for Sharpe ratio and validates new method effectiveness.
Study virtualized Delta, Sharp, and Pass moves for oriented virtual knots and links.
problem Conditions for unknotting oriented virtual knots and links.
method Local moves (Delta, Sharp, Pass) for oriented virtual links.
result Lower bounds for the unknotting numbers are proven and shown to be best possible.
We derive a sharp cusp count for finite volume complex hyperbolic surfaces which admit smooth toroidal compactifications. We use this result, and the techniques developed in [DiC12], to study the geometry of cusped complex hyperbolic surfaces and their compactifications.
Classifies graphs with Bonnet-Myers sharp curvature and connects it to Bakry-Émery curvature.
problem Classifying graphs with specific curvature properties.
method Introducing Bonnet-Myers and Lichnerowicz sharpness in Ollivier Ricci curvature, combinatorial reformulation, and relating to Bakry-Émery curvature.
result Classification of graphs including hypercubes, cocktail party graphs, and Johnson graphs J(2n,n). Sharp inequalities link manifold's systole to curvature of boundary.
problem Finding relationships between manifold's systole and curvature.
method Proved inequalities relating homological systoles to scalar and mean curvature.
result Equality case implies universal cover is a cylinder.
Derives a sharp inequality for trace-free matrices with applications to hypersurfaces.
problem Classifying conformally flat hypersurfaces and characterizing rotational hypersurfaces.
method Derives a sharp inequality relating eigenvalues of trace-free matrices and applies it to hypersurfaces.
result New proof of the classification of conformally flat hypersurfaces and construction of a functional for rotational hypersurfaces.
Sharp gradient estimates for positive Ricci curvature manifolds.
problem Understanding geometric properties of manifolds with positive Ricci curvature.
method Proving sharp gradient estimates and monotonicity formulae.
result Sharp gradient estimates and monotonicity formulae for positive Ricci curvature manifolds.
New knot invariant s♯ reveals unexpected phenomena.
problem Understanding the new knot invariant s♯ and its properties. method Computations and new characterizations of s♯ using immersed cobordisms. result Invariant s♯ does not agree with s and is not additive under connected sums. Paper proves anisotropic Minkowski inequality and related inequalities.
problem Proving anisotropic Minkowski inequality and related inequalities.
method Utilizes a nonlinear potential theoretic approach.
result Sharp anisotropic Minkowski inequality and related inequalities proved.
Sharp bounds on diameter and eigenvalues for amply regular graphs.
problem Finding bounds for amply regular graphs' diameter and eigenvalues.
method New ideas relating discrete Ricci curvature to local matching properties, including a novel construction of a regular bipartite graph.
result Sharp diameter and eigenvalue bounds for amply regular graphs.
Sharp lower bounds for modular invariants and Dehn twist coefficients in genus 2 and 3.
problem Finding sharp lower bounds for modular invariants and Dehn twist coefficients.
method Analyzing the relation between fractional Dehn twists and modular invariants, classifying pseudo-periodic maps, and proving rigidity properties.
result Sharp lower bounds for modular invariants and Dehn twist coefficients in genus 2 and 3.
Study cohomology classes related to n-harmonic morphisms and F-harmonic maps.
problem Understanding cohomology classes associated with n-harmonic morphisms and F-harmonic maps. method Utilizing the n-conservation law (2.6) to obtain sharp results. result Sharp results on cohomology classes related to n-harmonic morphisms and F-harmonic maps. Sharp gradient estimate on hyperbolic spaces derived from heat kernel.
problem Finding sharp Li-Yau type gradient estimates for positive solutions of heat equations.
method Introduced Li-Yau multiplier set and used recurrence relations of heat kernels on hyperbolic spaces.
result Optimal Li-Yau gradient estimate on hyperbolic spaces.
The paper predicts and explains the decay of stock anomaly performance over time.
problem Predicting and explaining the drop in risk-adjusted performance of stock anomalies.
method The authors propose ex-ante characteristics based on hypotheses of out-of-sample decay and in-sample overfitting.
result The year of publication explains 30% of the variance in Sharpe decay across factors.
Sharp inequality on Siegel domain involving weighted norms and sub-Laplacian.
problem Establishing a Sobolev trace inequality on a specific domain.
method Using weighted norms and fractional powers of sub-Laplacian on Heisenberg group.
result Sharp Sobolev trace inequality on Siegel domain involving weighted norms.
This note develops certain sharp inequalities relating the fractional Sobolev capacity of a set to its standard volume and fractional perimeter.
Noise in linear networks minimizes sharpness and leads to shrinkage-thresholding.
problem Minimizing sharpness in diagonal linear networks.
method Stochastic sharpness-aware minimization (SAM) with isotropic noise.
result Noise forces shrinkage-thresholding of true parameters.
Sharp inequality proved in 3D hyperbolic spaces using flow methods.
problem Proving a sharp Minkowski-type inequality in Cartan-Hadamard 3-spaces.
method Using harmonic mean curvature flow to prove the inequality.
result Sharpened estimates for total mean curvature in hyperbolic 3-space.
The study finds inequalities in warped product manifolds linking isoperimetric and curvature integrals.
problem Finding inequalities in warped product manifolds.
method Proving isoperimetric inequalities and relating them to curvature integrals.
result Sharp eigenvalue and geometric inequalities in space forms.
Derives new monotone quantities for p-harmonic functions on asymptotically flat 3-manifolds.
problem Estimating the mass of 3-manifolds with non-negative scalar curvature and minimal boundary.
method Derives monotone quantities for p-harmonic functions and applies them to derive a sharp mass-capacity estimate.
result Derives a sharp mass-capacity estimate relating the ADM mass of a 3-manifold to the p-capacity of its boundary.
The paper refines Steinerberger curvature for block graphs and bridges.
problem Understanding curvature in graph theory.
method Formulas and relations for curvature in block graphs and graph bridges.
result Self-centered Bonnet-Myers sharp graphs are antipodal.
Sharp Talenti-type comparison theorem for p-Laplacian on RCD(K,N) spaces.
problem Understanding the p-Laplacian on RCD(K,N) spaces.
method Proving a Talenti-type comparison theorem.
result Sharp, rigid and stable Talenti-type comparison theorem.
Sharp bounds and rigidity theorems for eigenvalues on manifolds.
problem Estimating eigenvalues and characterizing rigidity on manifolds.
method Volume comparison, Escobar-type eigenvalue comparisons, and Reilly formula.
result Sharp bounds and rigidity conditions for eigenvalues on manifolds.
In this paper, we give an easy proof of the main results of Andrews and Clutterbuck's paper [J. Amer. Math. Soc. 24 (2011), no. 3, 899--916], which gives both a sharp lower bound for the spectral gap of a Schröinger operator and a sharp modulus of concavity for the logarithm of the corresponding first eigenfunction. We…
Proves inequalities for hypersurfaces in the sphere, solving a long-standing problem.
problem Proving inequalities for hypersurfaces in the sphere.
method Using mixed volumes and quermassintegrals, the authors prove inequalities equivalent to a sharp relation among three adjacent quermassintegrals.
result Proves inequalities for hypersurfaces in the sphere, equivalent to a sharp relation among three adjacent quermassintegrals.
The study examines rigidity and stability of gradient estimates on surfaces and manifolds.
problem Rigidity and stability of gradient estimates for positive harmonic functions and solutions to heat equations.
method Sharp gradient estimates for positive harmonic functions and solutions to heat equations on surfaces and manifolds with nonnegative curvature.
result Obtained rigidity and stability results for gradient estimates.
Sharp inequality between TV and Hellinger distances for Gaussian mixtures.
problem Understanding the relationship between total variation and Hellinger distances for Gaussian mixtures.
method Established a general upper bound on Hellinger distance in terms of TV distance raised to a power, demonstrating sharpness with specific examples.
result The Hellinger distance between two Gaussian mixtures is bounded by the TV distance raised to a power 1−o(1), where o(1) is of order 1/loglog(1/TV). Instanton homology detects 2-torsion in fibered knots.
problem Detecting 2-torsion in instanton homology for fibered knots.
method Using sutured instanton theory to derive a formula for I♯(Y,K;C) and comparing dimensions. result Proves the presence of 2-torsion in instanton homology for null-homologous fibered knots.
New invariants detect a specific graph in spatial webs.
problem Detecting specific graphs in spatial webs.
method Introduced new invariants and used spectral sequences.
result Proved invariants detect the planar theta graph.
We prove several results about the multiplicity of the first Steklov eigenvalues on compact surfaces with boundary. We improve some bounds on the multiplicity, especially for the first eigenvalue, and we prove they are sharp on some surfaces of small genus. In a previous article, we defined a new chromatic invariant of…
We obtain some improved essentially sharp Kakeya-Nikodym estimates for eigenfunctions in two-dimensions. We obtain these by proving stronger related microlocal estimates involving a natural decomposition of phase space that is adapted to the geodesic flow.
The paper improves Fréchet bounds and sharpens their applicability.
problem Uncertainty in joint distribution and marginals in multivariate distributions.
method Optimal transport duality, representation of increasing convex functionals, explicit computation of conjugates.
result Improved Fréchet-Hoeffding bounds are pointwise sharp under uncertainty in marginals but not in absence.
Proves a formula for instanton Floer homology of knots.
problem Calculating changes in instanton Floer homology for knots.
method Uses sutured instanton homology and the octahedral lemma.
result Derives an integral surgery formula for framed instanton homology.
We prove three new monotonicity formulas for manifolds with a lower Ricci curvature bound and show that they are connected to rate of convergence to tangent cones. In fact, we show that the derivative of each of these three monotone quantities is bounded from below in terms of the Gromov-Hausdorff distance to the neare…
SAM improves deep learning by relaxing Bayes objective.
problem Improving generalization in deep learning models.
method SAM as a relaxation of Bayes objective using Fenchel biconjugate.
result SAM connects adversarial and Bayesian methods for robustness.
In this paper we prove mixed norm estimates for Riesz transforms related to Laplace--Beltrami operators on compact Riemannian symmetric spaces of rank one. These operators are closely related to the Riesz transforms for Jacobi polynomials expansions. The key point is to obtain sharp estimates for the kernel of the Jaco…
We study the spherical cap packing problem with a probabilistic approach. Such probabilistic considerations result in an asymptotic sharp universal uniform bound on the maximal inner product between any set of unit vectors and a stochastically independent uniformly distributed unit vector. When the set of unit vectors …
The paper examines eigenvalues and inequalities on Riemannian manifolds.
problem Eigenvalue behavior and volume growth on Riemannian manifolds.
method Analyzes the asymptotic behavior of the first eigenvalues of balls on Riemannian manifolds.
result Sharp estimates of volume growth and Hardy inequalities under spectral conditions.
Study new types of submanifolds in Kenmotsu manifolds.
problem Characterize and study new types of warped product skew CR-submanifolds.
method Interchange factors of warped product skew CR-submanifolds and derive lower bounds of the square norm of second fundamental form.
result Derived a lower bound of the square norm of second fundamental form with equality cases.
The paper introduces a new geometric capacity and proves inequalities related to it.
problem Developing a new geometric capacity and comparing it to classical quantities.
method Introducing the general p-affine capacity and proving its properties and inequalities. result Sharp geometric inequalities for the general p-affine capacity are derived. The paper shows how to uniquely determine a connection up to gauge.
problem Determining a connection up to gauge from its holonomies.
method Using hyperbolic dynamical systems and transport operators.
result The primitive trace map is locally injective near generic points.
New flatness measure for deep networks invariant to scaling.
problem Lack of invariant flatness measures for deep networks under parameter rescaling.
method Introduced a quotient manifold structure and Hessian-based invariant flatness measure.
result Confirms that Large-Batch SGD minima are sharper than Small-Batch SGD minima.
New technique connects instanton Floer homology to Heegaard diagrams for knots and 3-manifolds.
problem Accessing structural properties of instanton Floer homology.
method Developed a new technique using Heegaard diagrams and sutures.
result Established a relation between instanton knot homology and Heegaard diagrams for (1,1)-knots.