The delayed-choice quantum eraser is often misinterpreted as evidence of retrocausality. This paper provides a physical alternative based on the XLG cosmology's Photon Helix model. Photons emitted from a fixed source at a constant angle form an ordered phase-locked sequence propagating through the KuiQuark Sea. Interference fringes arise from phase superposition of the KuiQuark wave, not from single-photon path superposition. Quantum erasure does not retroactively recover interference; it selects a phase component from pre-existing detection data. The delayed choice operates on post-collected data, not on photon propagation history. This interpretation is consistent with the double-slit two-layer wave mechanism in XLG cosmology and reproduces all measured correlations without retrocausality.
The delayed-choice quantum eraser is often misinterpreted as evidence of retrocausality. This paper provides a physical alternative based on the XLG cosmology's Photon Helix model. Photons emitted from a fixed source at a constant angle form an ordered phase-locked sequence propagating through the KuiQuark Sea. Interference fringes arise from phase superposition of the KuiQuark wave, not from single-photon path superposition. Quantum erasure does not retroactively recover interference; it selects a phase component from pre-existing detection data. The delayed choice operates on post-collected data, not on photon propagation history. This interpretation is consistent with the double-slit two-layer wave mechanism in XLG cosmology and reproduces all measured correlations without retrocausality.
Traditional quantum mechanics interprets double-slit interference, delayed-choice experiment, quantum eraser experiment, and quantum Zeno effect as fundamental counter-intuitive characteristics of microscopic quantum systems. The conventional framework relies on wave-particle duality, abstract wavefunction collapse, observer-dependent quantum state switching, and information-dominated physical behavior. This paper abandons the traditional assumption of empty vacuum and wave-particle duality. Based on the discrete, elastic, compressible KuiQuark sea medium model, we provide a fully classical, deterministic, mechanical unification of the four core quantum interference phenomena. All quantum paradoxes are eliminated completely. The so-called quantum wave behavior is not an intrinsic property of microscopic particles, but a macroscopic statistical effect induced by particle-excited medium secondary waves and medium ordered structures in vacuum. We further classify two independent physical mechanisms of interference: multi-photon strong-light interference originates from the superposition of helical trajectories of real photon spherical shell clusters, while single-electron sequential interference originates purely from the coherent superposition of KuiQuark medium secondary waves. The delayed-choice effect contains no retro-causality; it only destroys the existing ordered medium channel field after the particle has passed the slit. The quantum eraser effect is a precise mechanical reverse compensation of medium deformation, realizing reversible recovery of medium coherence. The quantum Zeno effect is a dual mechanical locking mechanism: continuous high-frequency detection disrupts balanced medium distribution and forms large-scale reverse medium impact force, which counteracts the forward kinetic energy of particles and freezes microscopic evolution. This study fundamentally eliminates the non-classical hypothesis of traditional quantum mechanics and provides a new deterministic medium-based physical foundation for microscopic interference and quantum observation effects.
Quantum superposition lies at the core of quantum mechanics and has been applied to various quantum technologies. Over the past few decades, Wheeler’s delayed-choice thought experiment has been extensively examined to explore the wave-particle duality of the complementary nature of quantum mechanics. The essence of the delayed-choice quantum eraser lies in the contradictory quantum property that violates the cause-effect relationship in classical physics. Our experiments present empirical evidence of the quantum eraser using coherent photon pairs provided in a noninteracting Mach-Zehnder interferometer for the polarization-basis control of output photons. The observed interference fringe is the direct proof of the quantum eraser, where the violation of the cause-effect relationship is due to the selective choices of the measurement events.
The delayed-choice thought experiment proposed by Wheeler has been demonstrated over the last several decades for the wave-particle duality of a single photon. The delayed-choice quantum eraser proposed by Scully and Druhl has also been intensively studied for the violation of the cause-effect relation of a single photon as well as a pair of entangled photons in an interferometric system. Here, a coherence interpretation is conducted for the nonlocal realism of the space-like separated photons observed in Phys. Rev. Lett. 84, 1 (2000). As a result, coherence solutions of the observed nonlocal fringes are deterministically derived from coincidence detection-caused selective measurements, where the resulting product-basis superposition becomes the origin of the otherwise quantum mystery of the nonlocal fringes. For this, a fixed sum-phase relation between entangled photons is a prerequisite, which cannot be explained by conventional particle nature-based quantum mechanics.
Abstract Wave–particle duality is a counterintuitive nature of quantum physics that challenges many common-sense assumptions, and Young’s double-slit interference is a prototypical example. While most quantum erasure experiments emphasized the choice of erasing or marking the which-path information of one quantum system, we use frequency entanglement to report a nonlocal temporal double-slit interferometer such that the which-time information determines the wave-like or particle-like behaviors. Since frequency-entangled photons are created simultaneously by using spontaneous parametric down conversion, the mark of temporal distinguishability is readily prepared by delaying one of the entangled photons, and its quantum eraser is implemented by using spectrally resolved detection with a tunable delayed choice. These results may provide an alternative aspect and insight into the role of the temporal degree in quantum-light complementarity and photon interference.
Ever since the proposal of delayed choice quantum erasure and subsequent realization in the experiment by Kim et al., the interpretation and implications of delayed-choice experiments have remained a subject of intense foundational debate. This paper resolves the apparent paradox attached to the experiment using standard quantum mechanics. Using an extended Mach-Zehnder interferometer which captures every operational feature of the original experiment, we show that choosing between which-path and erasure detectors is simply a choice of measurement bases, which does not rewrite a photon's past. Furthermore, by mapping the experiment to a two-way Stern-Gerlach framework, we prove that quantum erasure is an expected result of measuring entangled states, not a physical anomaly. Ultimately, through a pedagogical game, we illustrate that the illusion of retrocausality arises from asking illegitimate questions, and that a forward-in-time description is entirely sufficient to explain the logic.
The “Delayed-choice quantum eraser” experiment is traditionally interpreted in the popular science mainstream as proof of retrocausality, while in the strict Copenhagen interpretation, it is reduced to fundamentally random post-selection. In this paper, this paradox is completely demystified within the framework of the Topological-Plexor kinematics of the vacuum. It is shown that the macroscopic chronology of events is never violated, and quantum randomness is an illusion. This illusion arises solely from ignoring the hidden fundamental 4D-metric (GAB) and the superluminal phase transfer by a Sine-Gordon soliton. In our discrete model, the impact of the Signal photon on the screen (in the past) generates a topological kink, which propagates along a 1D-chord at a velocity v4D ≫ c and deterministically “reprograms” the spinor phase of the Idler photon on the fly. The subsequent behavior of the Idler photon at the beam splitters (in the future) is not a probabilistic choice, but a rigid mechanical consequence of the Signal photon’s impact coordinate. The introduction of a macroscopic No-Signaling Theorem proves that this mechanism does not violate Special Relativity (SR). The Topological-Plexor paradigm (TPN/PPU) restores absolute causality, eliminates quantum mysticism, and paves the way for describing extreme cosmological states of matter.