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Research Article · Preprint Mathematics

Three-point positivity for weighted products of Riemann theta density powers

Scott Schubr

Luminary Oddities

  • Mathematics
  • Classical and Real Analysis
Primary subject
Mathematics
Paper type
Research Article
Manuscript stage
Preprint
Manuscript
Archived
Edition
2 · Permanent link

Overview

Abstract

We give an explicit curvature argument for three-point positivity of weighted products of the Riemann theta density. If Φ is the usual positive even density, then for every α≥5/8 and every nonnegative measure ν with 0<∫Φ(s)^(2α) dν(s)<∞, the function ∫Φ(s+t/2)^αΦ(s-t/2)^α dν(s) has positive definite three-point translation matrices at distinct real positions. Repeated positions give positive semidefinite matrices. The proof combines a general curvature criterion with positive-Laplace estimates for the complete theta-series tail. All infinite-tail bounds and rational interval estimates are provided explicitly. The result concerns three-point matrices.

Keywords theta density · three-point positivity · positive definite kernels · curvature · weighted products

Scope of the work

Strict three-point translation positivity for nonnegative center mixtures of products of Riemann theta density powers for every exponent at least 5/8.

Reproduction notes

7-page manuscript and 7 package members. Compile main.tex with Tectonic or compatible LaTeX. Install the pinned SymPy 1.14.0 requirement and run python exact-controls.py and python -O exact-controls.py for exact symbolic/rational curvature and determinant identities. The complete infinite-tail arguments are in the manuscript.

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Author disclosures

AI-assisted tools supported research exploration, literature review, manuscript preparation and internal verification. The author retains responsibility for the work. Internal AI-assisted and computational checks are distinct from external human peer review.

A stable scholarly record

Cite this edition

Scott Schubr. (2026). Three-point positivity for weighted products of Riemann theta density powers (Version 2). Luminary Research Archive. https://research.luminaryoddities.com/three-point-positivity-for-weighted-riemann-theta-products/v/2

BibTeX
@techreport{luminary_three_point_positivity_for_weighted_riemann_theta_products_v2,
  title = {Three-point positivity for weighted products of Riemann theta density powers},
  author = {Scott Schubr},
  year = {2026},
  institution = {Luminary Research Archive},
  type = {Research Article},
  note = {Version 2},
  url = {https://research.luminaryoddities.com/three-point-positivity-for-weighted-riemann-theta-products/v/2}
}

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