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Equation 17 · Part 1 · The Corner of the Equivalence Principle No Experiment Has Touched

Symbol hateta_coh

η^coh\hat\eta_{coh}
η^coh\hat\eta_{coh}

What this part means

hatetaca_coh is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.

Its job in the formula

hatetaca_coh is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.

The passage around this formula

…quantum, coherence-dependent piece to an Eötvös-ratio uncertainty in the low 10⁻⁹ range, roughly a hundredfold improvement over earlier internal-state tests [ 7 ] — this is the one bound in the record that reaches into η^coh\hat\eta_{coh} rather than stopping at η^diag\hat\eta_{diag} . Chris Overstreet and colleagues’ gravitational Aharonov-Bohm measurement, using a kilogram-scale source mass to imprint a phase on a single atom’s spatially superposed wavefunction, sits adjacent to η^sup\hat\eta_{sup} , probing how the atom’s own…

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