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arXiv · 2608.02185

A Standard Quantum Mechanical Treatment to Rationalize the Delayed-Choice Quantum Eraser

Vipul Badhan·Pranvi·Samreet Dhillon·Bindiya Arora
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Abstract

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.

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Vipul Badhan, Pranvi, Samreet Dhillon, Bindiya Arora. 2026-08-03. A Standard Quantum Mechanical Treatment to Rationalize the Delayed-Choice Quantum Eraser. https://arxiv.org/abs/2608.02185

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