The Double-Slit Experiment is a Test of Topological Invariance Across Different Matter Probes

The double-slit experiment is conventionally interpreted as evidence for wave-particle duality. This paper proposes an alternative interpretation grounded in the contological framework (Contology and its mathematical topology companion). We argue that the interference pattern is not a property of the probe (photon, electron, etc.), but a topological invariant of the permanent apparatus: void (the holes as folds), space (the lattice between barrier and screen), and matter (the barrier and screen as boundary conditions). Different matter probes—photon (zero rest mass, trivial braid) vs. electron (non-zero rest mass, non-trivial braid with fractal structure)—traverse the same topological template but reveal it at different resolutions. The photon, as a pure exchange morphism (Fold 2), traces the pattern perfectly. The electron, with internal Fold 3 complexity, produces a blurrier pattern. A resolution theorem is proposed relating interference contrast to the fractal strand thickness of the probe. Thus, the double-slit experiment is not a test of wave vs. particle, but a test of topological invariance across different matter probes.