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The Centered Collision Sum
collision

The Centered Collision Sum

Subtract the family bias and the divergence vanishes. The centered sum converges at s=1, and the rate of convergence is controlled by the classical zero-free region.
October 2023
Alex Petty
The Collision Fluctuation Sum
collision

The Collision Fluctuation Sum

The collision deviations, summed over primes, drift downward at the Mertens rate. The drift has a sign, a constant, and a structural origin in the digit function.
April 2023
Alex Petty
Silent Primes
collision

Silent Primes

At seven primes in base 10, the collision count is exactly zero. The recipe that finds them involves the bin partition and a specific floor-function identity.
January 2023
Alex Petty
The Character Structure of the Collision Fluctuation
collision

The Character Structure of the Collision Fluctuation

The collision fluctuation decomposes over Dirichlet characters. Only the odd characters survive, forced there by the complement involution. This is where the algebra begins.
October 2022
Alex Petty
Bin Derangements and the Gate Width Theorem
spectral

Bin Derangements and the Gate Width Theorem

Nine multipliers produce zero collisions at every prime in base 10. The count is exactly b-1, independent of the prime. The proof identifies the deranging set explicitly.
July 2022
Alex Petty
Phase-Filtered Ramanujan Sums and the Spectral Gate
spectral

Phase-Filtered Ramanujan Sums and the Spectral Gate

The last digit of a prime controls which spectral modes survive. A phase filter built from Ramanujan sums explains the gate, and the gate width is universal across primes.
April 2022
Alex Petty
The Autocorrelation Formula
spectral

The Autocorrelation Formula

The cross-spectral function had resisted a closed form. It turned out to factor through the digit function evaluated at shifted arguments. The formula closes the spectral chain.
January 2022
Alex Petty
The Spectral Power of the Digit Function
spectral

The Spectral Power of the Digit Function

The squared bin sizes of the digit function control the alignment limit, the spectral structure, and the collision count. One object, three roles.
October 2021
Alex Petty
The Spectral Structure of Fractional Fields
spectral

The Spectral Structure of Fractional Fields

The eigenvalues of the cross-alignment matrix are determined by the cyclic autocorrelation of the digit function. One formula gives the entire spectrum.
July 2021
Alex Petty
The Cross-Alignment Matrix
spectral

The Cross-Alignment Matrix

Compare every fraction to every other, digit by digit. The result is a symmetric matrix whose eigenvalues encode the internal structure of the fractional field.
April 2021
Alex Petty
The Coherence Decomposition
spectral

The Coherence Decomposition

Alignment splits into two parts: a focused component from the repetend orbit, and a pairwise component from cross-matches. The decomposition explains why some integers are more coherent than others.
January 2021
Alex Petty
Primes and the Major Scale
publication

Primes and the Major Scale

The primes that organize long division are the same primes that organize musical pitch. In base 30, the alignment deficit lattice produces the just major scale. In base 12, the Pythagorean comma.
October 2020
Alex Petty
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