Past-Selection Filtrations

Past-Selection Filtrations (PSF) is an operator-algebraic framework for quantum measurement that models observation as a progressive conditioning on stable records of the past, rather than as a fundamental physical collapse. The framework represents "past selection" through filtrations of von Neumann subalgebras equipped with faithful conditional expectations, allowing measurement histories to be treated as mathematically structured informational constraints. Within this formalism, decoherence and visibility loss emerge from record stabilization, linking quantum measurement to quantum information geometry and statistical distinguishability. This work derives quantitative bounds connecting interference visibility to quantum fidelity and Chernoff distinguishability measures, and analyzes delayed-choice scenarios through invariance properties of record-preserving normalizers. The framework also introduces "past rates" and "past curvature" diagnostics for characterizing the informational evolution of measurement histories. PSF reproduces standard quantum predictions while offering an alternative interpretation of collapse grounded in conditional structure rather than ontological reduction. Potential applications include quantum information theory, decoherence modeling, and foundational questions concerning measurement, time asymmetry, and macroscopic records. The poster will present the mathematical structure of PSF, illustrative examples, and its relationship to existing interpretations of quantum mechanics.