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Measure-Relational Algebra

A specification for data systems that carry measurement uncertainty. A stored quantity is a probability measure on a metrized domain, not a point; dependence is carried as data; computation is pushforward; and collapsing a measure to a single number is an explicit, audited operation rather than a silent default. The classical model of exact values is recovered inside it as a special case. The core is, in the manner of Codd’s 1970 paper, implementation-independent: it states what any conforming system must preserve, and provides the instruments to gauge what an implementation loses.

Collapse commutes with a numerical derivation, for every joint input law, if and only if the derivation is affine and with every measurable derivation if and only if the values were exact to begin with.

The central theorem. Everywhere else, the collapsed computation is a different computation, with a signed, quantifiable discrepancy.

Documents

Measure-Relational Algebra: The CorePDF

The specification: objects, operations, the non-commutation theorem and its instruments, the geophysical case, and seven open problems. arXiv, August 2026.

The Cost of Writing Down a NumberPDF

The companion essay for non-specialists: a forty-year ceiling that wasn’t there, the mechanism behind it, and why the repair is structural. Four pages.