Probing the Limits of Time-Symmetry and the Projection Postulate in Sequential Quantum Measurements

Piechocinska, Barbara

Published Nov 14, 2025• 0 citations

Abstract

This paper proposes two precise, platform-independent experiments that aim to test the foundational assumptions of quantum mechanics: namely, whether time-reversal symmetry holds exactly at the quantum level, and whether quantum measurements truly erase all information about unrealized possibilities. While inspired by larger theoretical ideas of generative wholeness, the experiments are intentionally designed in a model-agnostic way and can be implemented with current technologies such as trapped ions, superconducting qubits, or advanced photonic systems. The first experiment compares the statistical outcomes of a quantum system measured in one order with those when the same measurements are applied in reverse order. Under standard theory, no irreducible asymmetry should remain after all known disturbances are controlled. Detecting a residual asymmetry would signal a fundamental microscopic arrow of time. The second experiment examines whether a quantum system retains an intrinsic “memory” of measurements that were performed but whose results were ignored or not recorded. By comparing two sequences, one where an intermediate measurement is omitted entirely and another where it is performed but discarded, the design tests for subtle deviations from the standard projection rule. A confirmed deviation would indicate non-Markovian, intrinsic memory effects in quantum measurement itself. Both proposals are framed as “null tests”: if the orthodox theory is complete, the results should vanish within error bars. Any non-zero finding would open a doorway to new physics, probing the nature of time, measurement, and possibility in the quantum domain. Keywords: time asymmetry, projection postulate, quantum measurement, sequential measurements, intrinsic memory, non-Markovianity, trapped ions, superconducting qubits, photonics, foundational tests of quantum mechanics.

DOI: 10.5281/zenodo.17607993

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