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.

168,657 papers · 148 categories

Trend · papers per month

18365472 · May 202619922001200920172026
48 results for eigenvalue counting

We introduce a differential topological invariant for compact differentiable manifolds by counting the small eigenvalues of the Conformal Laplace operator. This invariant vanishes if and only if the manifold has a metric of positive scalar curvature. We show that the invariant does not increase under surgery of codimen…

2002-04-16abs ↗pdf ↗

Global propagator for massless Dirac operator defined and analyzed.

problem Analyzing the massless Dirac operator on 3-manifolds.
method Constructing propagator as sum of oscillatory integrals, providing global definitions and small time expansions.
result Explicit calculation of propagators' symbols and coefficients in eigenvalue counting functions.

Study sharp lower bounds on negative eigenvalues of magnetic Pauli operator.

problem Counting negative eigenvalues of magnetic Pauli operator.
method Reduction to boundary Dirac operator, Atiyah-Patodi-Singer index theory, Benjamin-Ono equation conservation law.
result New formula on the number of eigenvalues of magnetic Neumann Laplacian in semi-classical limit.

We consider an elliptic self-adjoint first order differential operator L acting on pairs (2-columns) of complex-valued half-densities over a connected compact 3-dimensional manifold without boundary. The principal symbol of the operator L is assumed to be trace-free and the subprincipal symbol is assumed to be zero. Gi…

2014-01-09abs ↗pdf ↗

The paper studies eigenvalues of Xin-Laplacian on Riemannian manifolds.

problem Eigenvalue problems related to Xin-Laplacian on Riemannian manifolds.
method Establishing general formulas and applying Chen-Cheng type results.
result Sharp estimates for the upper bound of the second nonzero eigenvalue of the Laplace-Beltrami operator.

Efficiently infers sparse networks from count data with reduced memory usage.

problem Sparse network inference for count data with high dimensions and dependencies.
method Improved Bigraphical Lasso using eigenvalue decomposition of Cartesian product graph.
result Reduced computational complexity from O(n2p2)O(n^2p^2) to O(n2+p2)O(n^2 + p^2).

Temporal coarse-graining of multi-sector default count data generates effective correlation matrices and rank copulas.

problem Explaining the difference in default dependence between monthly and annual aggregation.
method Dynamic low-rank state-space model with AR(1) latent credit-state factors.
result Effective correlation matrices and rank copulas are generated from monthly default count data.

The paper studies eigenvalues in gaps of the essential spectrum of a Bochner-Schrödinger operator.

problem Eigenvalue distribution in gaps of the essential spectrum of the Bochner-Schrödinger operator.
method Trace asymptotics formula and Weyl type asymptotic formula for eigenvalue counting function.
result The spectrum of HpH_{p} in the gap is discrete.

The study counts units and eigenvalue patterns in SL_n(Z) and Sp_{2n}(Z) in thin tubes.

problem Counting totally real units and eigenvalue patterns in SL_n(Z) and Sp_{2n}(Z) in thin tubes.
method Analyzes directional entropy of logarithmic embeddings and eigenvalue data in thin tubes around rays.
result The number of objects grows exponentially with the directional entropy, providing bounds for conjugacy classes.

This article shows that counting or computing the small eigenvalues of the Witten Laplacian in the semi-classical limit can be done without assuming that the potential is a Morse function as the authors did in [LNV]. In connection with persistent cohomology, we prove that the rescaled logarithms of these small eigenval…

2020-02-17abs ↗pdf ↗

We discuss inverse resonance scattering for the Laplacian on a rotationally symmetric manifold M=(0,)×YM = (0,\infty) \times Y whose rotation radius is constant outside some compact interval. The Laplacian on MM is unitarily equivalent to a direct sum of one-dimensional Schrödinger operators with compactly supported potenti…

2019-04-18abs ↗pdf ↗

Let MSn+1Rn+2M\subset \mathbb{S}^{n+1}\subset\mathbb{R}^{n+2} be a compact cmc rotational hypersurface of the (n+1)(n+1)-dimensional Euclidean unit sphere. Denote by A2|A|^2 the square of the norm of the second fundamental form and J(f)=ΔfnfA2fJ(f)=-Δf-nf-|A|^2f the stability or Jacobi operator. In this paper we compute the spectra of the…

2019-02-19abs ↗pdf ↗

We consider the interplay of point counts, singular cohomology, étale cohomology, eigenvalues of the Frobenius and the Grothendieck ring of varieties for two families of varieties: spaces of rational maps and moduli spaces of marked, degree dd rational curves in Pn\mathbb{P}^n. We deduce as special cases algebro-geome…

2015-06-08abs ↗pdf ↗

We prove a Weyl-type fractal upper bound for the spectrum of the damped wave equation, on a negatively curved compact manifold. It is known that most of the eigenvalues have an imaginary part close to the average of the damping function. We count the number of eigenvalues in a given horizontal strip deviating from this…

2009-04-10abs ↗pdf ↗

The paper studies eigenvalues and stability of hypersurfaces in spheres.

problem Finding eigenvalues and stability of hypersurfaces in spheres.
method Derives equations for mean curvature and uses numerical methods to compute eigenvalues.
result Numerical computation of eigenvalues and stability indices for specific hypersurfaces.

In this note, we consider a fixed vector field VV on S2S^2 and study the distribution of points which lie on the nodal set (of a random spherical harmonic) where VV is also tangent. We show that the expected value of the corresponding counting function is asymptotic to the eigenvalue with a leading coefficient that i…

2018-09-05abs ↗pdf ↗

We consider the SL(2,R)SL(2,R) action on moduli spaces of quadratic differentials. If μμ is an SL(2,R)SL(2,R)-invariant probability measure, crucial information about the associated representation on L2(μ)L^2(μ) (and in particular, fine asymptotics for decay of correlations of the diagonal action, the Teichmüller flow) is encoded …

2010-11-24abs ↗pdf ↗

Graph Neural Networks outperform the Weisfeiler-Lehman algorithm in representation power.

problem Limited representation power of Graph Neural Networks compared to the Weisfeiler-Lehman algorithm.
method Algebraic analysis using eigenvalue decomposition of graph operators.
result Graph Neural Networks produce more discriminative representations than the Weisfeiler-Lehman algorithm.

The paper describes correlations of spectra for higher rank Anosov representations.

problem Understanding correlations of spectra for Anosov representations of higher rank groups.
method Relates correlation problem to counting projections in truncated hypertubes.
result Extends previous work on rank one representations to higher rank.

The paper extends Weyl's law to CROSSes, showing sharpness and polynomial improvement.

problem Understanding the error term in Weyl's law for different types of manifolds.
method Analyzing the Laplacian eigenvalues on Compact Rank One Symmetric Spaces (CROSSes).
result For CROSSes, the error term in Weyl's law is sharp, and for products of CROSSes, it can be polynomially improved.

The study examines numerical aspects of Karhunen-Loève expansions for stochastic processes.

problem Constructing Karhunen-Loève expansions for second-order stochastic processes.
method Spectral decomposition of covariance operator via Fredholm integral equation, discretization, singular value decomposition of weight-scaled sample matrix.
result Consistent solutions for model-based and data-driven KLE construction, characterized by convergence of SVD-based eigenvalue estimates and KL coefficients distributions.

The study bounds harmonic functions on manifolds with nonnegative Ricci curvature.

problem Bounding harmonic functions on manifolds with specific curvature properties.
method Analyzing the asymptotic volume ratio and eigenvalue counting function.
result Sharp upper bounds for harmonic functions with polynomial growth.

Flow Matching for count data improves sample quality and efficiency.

problem Mapping between count distributions across batches or time points in high-dimensional count data.
method count-FM, a flow-matching framework based on a continuous-time birth-death process with local unit jumps.
result count-FM achieves better sample quality than representative baselines while using fewer parameters.

A new method, Count-MORL, improves offline reinforcement learning by using state-action frequency.

problem Improving offline reinforcement learning performance.
method Integrates count-based conservatism into model-based offline reinforcement learning.
result The learned policy is near-optimal and outperforms existing methods.

Proposes a method to reconcile count time series forecasts.

problem No formal framework for probabilistic reconciliation of count time series.
method Generalizes Bayes' rule for reconciling real-valued and count variables.
result Improves forecast accuracy for count variables compared to Gaussian reconciliation.

The paper proposes count echo state networks for forecasting graduate student enrollments.

problem Forecasting graduate student enrollments from historical data.
method Developed hierarchical count echo state networks and compared them to Poisson autoregressions and negative binomial models.
result Hierarchical negative binomial based echo state network is the superior model.

Counted essential surfaces in a knot's exterior, finding a unique pattern.

problem Counting essential surfaces in a knot's exterior.
method Counted essential surfaces by genus, using Euler totient function. Showed normal surfaces are connected by counting their components. Used Agol, Hass, and Thurston's tools to convert component counting into orbit counting.
result Found a unique pattern in the number of essential surfaces by genus.

Counting objects in digital images is a process that should be replaced by machines. This tedious task is time consuming and prone to errors due to fatigue of human annotators. The goal is to have a system that takes as input an image and returns a count of the objects inside and justification for the prediction in the…

2017-03-25abs ↗pdf ↗

Better neural arithmetic logic units improve cell counting model generalization.

problem Neural networks struggle with high cell counts outside training data range.
method Introduced Neural Arithmetic Logic Units (NALU) for arithmetic operations in existing architectures.
result Improved cell counting accuracy for higher numeric ranges with better generalization.