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Sharp Quadratic Smoothing for Truncated Simplex Sums

Scott Schubr

Luminary Oddities LLC

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

Overview

Abstract

For every nonnegative integer radius, we prove joint log-concavity of the raw three-dimensional truncated simplex lattice sum at arbitrary real endpoints when each independent real power is at least two. The coordinatewise threshold two is sharp. Exhaustive cell coverage and exact positive-coefficient polynomial identities certify the quadratic endpoint over unbounded parameter orthants, rather than numerical samples or finite parameter cutoffs. In every dimension, the same endpoint holds with up to two unrestricted occupancies and arbitrarily many binary matroid companions with activities in [0,1]. Degree-elevated homogenization, classical complete-log-concavity and compensated composition supply that extension. The unrestricted quadratic simplex problem in dimensions four and higher remains open.

Keywords Classical and Real Analysis · Combinatorics and Graph Theory

Scope of the work

For every nonnegative integer radius, we prove joint log-concavity of the raw three-dimensional truncated simplex lattice sum at arbitrary real endpoints when each independent real power is at least two. The coordinatewise threshold two is sharp. Exhaustive cell coverage and exact positive-coefficient polynomial identities certify the quadratic endpoint over unbounded parameter orthants, rather than numerical samples or finite parameter cutoffs. In every dimension, the same endpoint holds with up to two unrestricted occupancies and arbitrarily many binary matroid companions with activities in [0,1]. Degree-elevated homogenization, classical complete-log-concavity and compensated composition supply that extension. The unrestricted quadratic simplex problem in dimensions four and higher remains open. Integer-endpoint midpoint coverage in arbitrary dimension is prior Leake-Mohammadi Yekta via an explicit TU model; Speyer difference-bound overlap is stated only where actually established. Classical ALOV/BH/Prekopa and prior2D/fractional baseline are credited. No new integer TU principle, full higher-dimensional kernel solution, three-free matroid theorem, optimal degree elevation, worldwide priority or external human refereeing is claimed.

Reproduction notes

The approved 10-member package contains the complete 14-page paper, editable LaTeX sources and dependencies, reader/build instructions, scholarly references and a public checksum manifest, with necessary exact verification programs and certificates. Follow the included README and retain the package together. Exact finite certificates support the stated analytic argument; they do not certify external human peer review.

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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.

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Cite this edition

Scott Schubr. (2026). Sharp Quadratic Smoothing for Truncated Simplex Sums (Version 1). Luminary Research Archive. https://research.luminaryoddities.com/sharp-quadratic-smoothing-for-truncated-simplex-sums/v/1

BibTeX
@techreport{luminary_sharp_quadratic_smoothing_for_truncated_simplex_sums_v1,
  title = {Sharp Quadratic Smoothing for Truncated Simplex Sums},
  author = {Scott Schubr},
  year = {2026},
  institution = {Luminary Research Archive},
  type = {Research Article},
  note = {Version 1},
  url = {https://research.luminaryoddities.com/sharp-quadratic-smoothing-for-truncated-simplex-sums/v/1}
}

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