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Equation 27 · Part 1 · The Corner of the Equivalence Principle No Experiment Has Touched

Symbol hateta_sup

η^sup\hat\eta_{sup}
η^sup\hat\eta_{sup}

What this part means

the sits adjacent to.

Its job in the formula

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

Where the article explains it

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 extended quantum state couples to the field rather than treating the interferometer arms as two independent classical trajectories [ 10 ] .

The passage around this formula

…at the 10^{-15} level by MICROSCOPE, η^diag\hat\eta_{diag} constrained by every dual-species and clock test in the list, η^coh\hat\eta_{coh} constrained at the low- 10^{-9} level by Rosi and colleagues’ internal-superposition test, η^sup\hat\eta_{sup} constrained by Overstreet and colleagues’ gravitational Aharonov-Bohm result. The fifth column, η^ent\hat\eta_{ent} , has nothing in it — not a weak bound, not a preliminary number, nothing. The paper’s proposition on this point is not merely that the entangled component happens to be…

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Learn the underlying idea

A subscript is a label attached below a symbol. It often selects a time step, component, category, or member of a sequence.

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Sources cited in the article section

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