Evidence of macroscopically entangled protons in a mixed isotope crystal of KH$_{p}$D$_{1-p}$CO$_3$

TL;DR

This study provides evidence that protons in a mixed isotope crystal exhibit macroscopic quantum entanglement, challenging classical particle models and suggesting a quantum matter wave nature at room temperature.

Contribution

It demonstrates the existence of macroscopically entangled proton states in a mixed isotope crystal, supported by neutron scattering data and a new theoretical framework.

Findings

Neutron scattering reveals antisymmetrized macroscopic proton states.

Protons do not follow classical statistical distributions.

Raman spectra indicate isotope-independent sublattice structures.

Abstract

We examine whether protons and deuterons in the crystal of KH$_{0.76}$D$_{0.24}$CO$_3$ at 300 K are particles or matter waves. The neutron scattering function measured over a broad range of reciprocal space reveals the enhanced diffraction pattern anticipated for antisymmetrized macroscopic states for protons (fermions). These features exclude a statistical distribution of protons and deuterons. Raman spectra are consistent with a mixture of KHCO$_3$ and KDCO$_3$ sublattices whose isomorphous structures are independent of the isotope content. We propose a theoretical framework for decoherence-free proton and deuteron states.