Illusory Decoherence

Ijaz Durrani

Ruth E. Kastner

The idea that decoherence in a unitary-only quantum theory suffices to explain emergence of classical phenomena has been shown in the peer-reviewed literature to be seriously flawed due to circularity. However, claims continue to be made that this approach, also known as "Quantum Darwinism," is the correct way to understand classical emergence. This Letter reviews the basic problem and points out an additional logical flaw in the argument. It is concluded that the "Quantum Darwinism" program fails.

Sushanta Dattagupta, Sanjay Puri

Sagar Kapadia

Decoherence posits that the classical world emerges as an “apparent” phenomenondue to environmental entanglement, with a latent superposition persisting in the systemenvironment state. We argue that this interpretation introduces unnecessary complexity,proposing instead that quantum collapse is ontologically real, driven by the attenuation ofnon-preferred basis states’ probability amplitudes to zero and the amplification of a preferredbasis to unity. This model rejects the notion of an “illusory” classical world, asserting thatobserved reality is concrete, aligning with common-sense intuition. To test this, we proposea photonic Mach-Zehnder interferometer experiment to detect or rule out a latent superposition via post-measurement interference effects. A null interference result would supportour ontological collapse model, while recovered interference would favor decoherence. Weprovide mathematical formalisms, a detailed experimental protocol, and equipment specifications to challenge decoherence’s untested assumption of a latent superposition

Ding Jia