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A Thought Experiment on Photon Pulse Reconstruction in Extreme Environments

Craig Kyrle Strachan Davidson

Published Mar 24, 2024• 0 citations
Publisher

Abstract

This thought experiment explores what information can be inferred about a photon pulse’s journey through interactions if its initial properties are known or modeled. By comparing the observed pulse to a predicted baseline, one can probabilistically reconstruct interaction history, including photon number, polarization, frequency, and direction. The framework is conceptual and speculative, grounded in standard quantum mechanics, and extends ideas from quantum state tomography to extreme environments such as near black holes. Laboratory analogues may validate aspects of this framework, while astrophysical pulses provide conceptual insight into interaction histories in extreme gravitational conditions.

DOI
10.5281/zenodo.19202844

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This thought experiment explores what information can be inferred about a photon pulse’s journey through interactions if its initial properties are known or modeled. By comparing the observed pulse to a predicted baseline, one can probabilistically reconstruct interaction history, including photon number, polarization, frequency, and direction. The framework is conceptual and speculative, grounded in standard quantum mechanics, and extends ideas from quantum state tomography to extreme environments such as near black holes. Laboratory analogues may validate aspects of this framework, while astrophysical pulses provide conceptual insight into interaction histories in extreme gravitational conditions.
This conceptual paper introduces a framework for indirectly inferring the state of photons that remain unobserved, by analyzing their environmental perturbations — here termed bow waves and wakes. Extending principles from quantum state tomography and environment-assisted measurement, this approach treats the environment as a forensic record of photon interactions, using purpose-built conceptual tools such as quantum filters and tick sheets. By combining probabilistic inference with structured environmental observables, it may be possible to reconstruct photon number, polarization, frequency, and path without collapsing the photon’s quantum state. This work builds on prior conceptual tools from photon pulse reconstruction (Davidson, 2026; DOI: 10.5281/zenodo.19221581) and extends them toward observing the unobservable in a controlled theoretical framework.
IFT-ISE is a unified quantum–informational framework in which wave–particle behavior emerges from the interaction between informational structure, geometry, and time. The model extends the standard photonic Hilbert space by introducing an internal informational subsystem, not as a new force or interaction, but as a generator of relational constraints. The framework combines Informational Field Theory (IFT)—where spatial probability distributions arise from local informational entropy gradients—with Internal State Encoding (ISE), a discrete informational basis governing the accessibility of particle-like states. Within this perspective, informational asymmetry does not induce collapse through measurement, but generates relational time and state distinguishability within the local informational geometry. Since photons possess no proper time, the emergence of even minimal relational time renders wave-like propagation incompatible, enforcing particle-like behavior without invoking observer-induced collapse. This reinterpretation provides a physically transparent explanation for the extreme sensitivity of the double-slit experiment to infinitesimal which-path information. IFT-ISE reconstructs the double-slit experiment, predicts upstream coherence modulation prior to slit interaction, and extends naturally to black-hole horizons, where extreme informational geometry suppresses temporal accessibility and amplifies informational structure. Mathematical derivations, conceptual diagrams, and experimentally testable predictions are provided, offering a coherent informational foundation for quantum optical and gravitational boundary phenomena.
We propose that gravitational-wave distinguishability provides a universal, information-theoretic mechanism for decoherence in quantum superpositions involving massive systems. When alternative quantum histories imprint distinguishable gravitational radiation states into spacetime, which-branch information exists in principle even in the absence of measurement. This suppresses interference purely through unitary entanglement with the gravitational field. Unlike collapse models, this framework relies only on standard quantum mechanics and the information-carrying capacity of gravitational radiation. We argue heuristically that the Planck mass emerges as an information-theoretic crossover scale beyond which gravitationally induced decoherence becomes unavoidable. To clarify the conceptual content, we introduce a Schrödinger’s-cat–type thought experiment in which one branch of a quantum superposition produces colliding black holes and gravitational waves, while the other does not. In this limit case, spacetime itself functions as an irreversible which-branch environment. The analysis positions gravity not as a modifier of quantum mechanics, but as a universal information channel contributing to the quantum–classical transition.