Authors create déjà vu links in Legendrian geometry.
problem Understanding déjà vu moments in spacetime.
method Constructing Legendrian links with specific properties.
result Found examples of déjà vu links in various geometric settings.
We define the virtual bridge number vb(K) and the virtual unknotting number vu(K) invariants for virtual knots. For ordinary knots K they are closely related to the bridge number b(K) and the unknotting number u(K) and we have vu(K)≤u(K),vb(K)≤b(K). There are no ordinary knots K with b(K)=1. We…
Recently Pelayo-Vũ Ngoc classified semitoric integrable systems in terms of five symplectic invariants. Using this classification we define a family of metrics on the space of semitoric integrable systems. The resulting metric space is incomplete and we construct the completion.
New metrics fail adversarial tests, with some more robust than others.
problem Evaluation metrics for time-series anomaly detection were improved but not fully robust.
method Adversarial stress-testing of 12 adopted metrics on real benchmarks.
result Some metrics are more robust than others, with ROC-based metrics being gamed more often.
Using simple facts from harmonic analysis, namely Bernstein inequality and Plansherel isometry, we prove that the pseudodifferential equation Δαu+Vu=0 improves the Sobolev regularity of solutions provided the potential V is integrable with the critical power n/2α>1.
In this paper, energy function is used to investigate the eigen-solutions of −Δu+Vu=λu on the Riemannian manifolds. We give a new way to prove the positivity of the initial energy of energy function, which leads to a simple way to obtain the growth of eigen-solutions.
Generates semigroups for differential expressions on Riemannian manifolds.
problem Analyzing differential expressions on Riemannian manifolds.
method Study of generalized Ornstein-Uhlenbeck differential expressions and their maximal realizations.
result Generates analytic quasi-contractive semigroups in weighted Lp-spaces. The present paper is a continuation of Le Anh Vu's ones [13], [14], [15]. Specifically, the paper is concerned with the subclass of connected and simply connected MD5-groups such that their MD5-algebras G have the derived ideal G1:=[G,G]≡ R3. We sha…
In this paper, we study the gradient estimate for positive solutions to the following nonlinear heat equation problem ut−Δu=aulogu+Vu, u>0 on the compact Riemannian manifold (M,g) of dimension n and with non-negative Ricci curvature. Here a≤0 is a constant, V is a smooth function on M with $-…
In this paper, we consider the eigen-solutions of −Δu+Vu=λu, where Δ is the Laplacian on a non-compact complete Riemannian manifold. We develop Kato's methods on manifold and establish the growth of the eigen-solutions as r goes to infinity based on the asymptotical behaviors of Δr and V(x), where r=r(x) i…
Study concavity of solutions to elliptic equations under conformal deformations.
problem Establish concavity estimates for the principle eigenfunction of weighted Schrödinger operators.
method Analyzing the Dirichlet problem for the weighted Schrödinger operator \[-Δu + Vu = λρu\] with conformal connections.
result Partial resolution of Nguyen's conjecture on fundamental gap of horoconvex domains and power convexity estimate for solutions in spherical geometry.
Study analyzes perturbations in singular subspaces under random noise.
problem Understanding singular vector and subspace changes in signal-plus-noise models.
method Generalized Davis-Kahan-Wedin theorem for any unitarily invariant norm, considering ℓ∞ and ℓ2,∞ bounds. result Fine-grained insights into singular vector and subspace perturbations, including ℓ∞ and ℓ2,∞ bounds. Optimal transport reformulates multiple quantile hedging problem.
problem Multiple quantile hedging problem in incomplete markets.
method Reformulated as Monge optimal transport problem, introduced Kantorovitch version, proved no duality gap.
result Multiple quantile hedging problem can be seen as semi-discrete optimal transport problem.
A symplectic semitoric manifold is a symplectic 4-manifold endowed with a Hamiltonian (S1×R)-action satisfying certain conditions. The goal of this paper is to construct a new symplectic invariant of symplectic semitoric manifolds, the helix, and give applications. The helix is a symplectic analogu…
Paper introduces S3W distance for spherical probability distributions.
problem Comparing spherical probability distributions efficiently and accurately.
method S3W distance using stereographic projection and generalized Radon transform.
result Extensive theoretical analysis and evaluation of S3W performance.
The Clifford group for 2 qubits is divided into 20 orbits, each with 4608 matrices.
problem Understanding the structure of the Clifford group for 2 qubits.
method Equivalence relation based on local Clifford gates and analysis of orbits.
result The Clifford group for 2 qubits is divided into 20 orbits, each with 4608 matrices.
A generalized semitoric system F:=(J,H): M --> R^2 on a symplectic 4-manifold is an integrable system whose essential properties are that F is a proper map, its set of regular values is connected, J generates an S^1-action and is not necessarily proper. These systems can exhibit focus-focus singularities, which corresp…
This paper improves Green's function estimates for compact Kähler manifolds.
problem Estimating Green's function norms for compact Kähler manifolds without curvature bounds.
method Proves an improved integral estimate for Green's function under volume density condition.
result Improved global geometric estimates, including eigenvalue bounds for Laplacian.
Proposes a new metric for comparing shapes in different spaces.
problem Comparing shapes in different metric spaces with unequal mass.
method Developed a Partial Gromov-Wasserstein (PGW) metric and algorithms to solve it.
result PGW is a well-defined metric between metric measure spaces.
The paper estimates the measure of nodal sets for solutions to a specific type of Schrödinger equation.
problem Estimating the measure of nodal sets for solutions to a Schrödinger equation with a potential function.
method Developed a dividing iteration procedure to estimate the upper bound of the (n−1)-dimensional Hausdorff measure of the nodal set. result The upper bound of the measure of the nodal set is given by a specific formula involving the potential function's norms.
New algorithm for fast nonsmooth optimization with applications in image processing and machine learning.
problem Minimizing the sum of three convex functions with specific properties.
method PDDY algorithm, based on Davis-Yin splitting in a primal-dual product space.
result Sublinear and linear convergence rates in various scenarios, including strong convexity.