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Equation 120 · Part 6 · The Clock That Comes Back Wrong by Exactly Its Mass

subscript

ϕ≈keff g T2\phi\approx k_{\rm eff}\,g\,T^2
subscript

What this part means

The lower label selects a particular version, component, or indexed member of the quantity. For example, x₀ and xₜ can be values at different positions.

Its job in the formula

A subscript distinguishes a version, component, step, or member of a quantity. It does not automatically mean multiplication.

The passage around this formula

Here is the strongest objection this construction has to survive, and it is not hypothetical — it was argued in print for over a decade. In 2010, Müller, Peters, and Chu proposed that an ordinary light-pulse atom interferometer’s gravimeter phase already constitutes a measurement of the gravitational redshift at the atom’s Compton frequency mc2c^2/ℏ\hbar , reading the standard interferometer as an implicit realization of exactly the proper-time phase this paper formalizes [ 6 ] . Wolf, Blanchet, Bordé, Reynaud, Salomon, and Cohen-Tannoudji objected immediately: the standard three-pulse Mach–Zehnder gravimeter phase, computed by the ordinary classical-action method, is ϕ\phi≈\approx k_{\rm…

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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.

Open the illustrated subscripts: which member of a family? guide →

Sources cited in the surrounding passage

These citations provide research context; check each source for the exact claim it supports.