Finite theta interpolation and eventual Laguerre failure

Abstract

We construct positive finite reweightings of the actual integer-square theta atoms which reproduce any prescribed finite set of modular endpoint jets, converge to the complete theta density in every fixed source derivative norm, and nevertheless eventually violate the first Laguerre inequality. The first missed odd jet has an explicit strictly positive Gaussian-tail formula. More generally, every nonzero finite signed compact-scale mixture of these atoms has a nonzero odd endpoint jet, finitely many real transform zeros and infinitely many nonreal zeros. For the exact split into a finite surrogate and its complete arithmetic remainder, we determine the leading cancellation of both diagonal Laguerre densities and their cross term, uniformly on bounded horizontal strips including the real axis. Each diagonal has only finitely many absolute moments, although their complete combination decreases rapidly. Explicit source-seminorm bounds give a sufficient negativity onset. The positive interpolation mechanism is classical; the conclusions concern its explicit realization and global-sign obstruction in the actual theta atom family.