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Equation 142 · Part 1 · The Bend an Elevator Cannot Fake

superscript

7.6×10−217.6\times10^{-21}
superscript

What this part means

A raised number can be a power. When it is a label or bound, it selects a case or the upper limit of a sum; the formula’s structure distinguishes these uses.

Its job in the formula

A raised mark can be a power or an index. Its position and the surrounding notation determine which.

The passage around this formula

It is worth being honest about how far current best precision still has to travel to make a genuinely compact version of this measurement realistic. The most precise fractional frequency resolution reported to date, 7.6×\times10^{-21} , comes from comparing atoms at different heights inside a single shared optical lattice, where systematic effects common to both heights cancel almost completely [ 13 ] . If that exact resolution were ever achieved between two independently operated, physically separated network clocks — which is not what was demonstrated, and which faces a substantially harder common-mode-rejection problem — the same scaling gives h ∝\propto σy\sqrt{\sigma_y} and a required…

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Learn the underlying idea

An exponent tells how a base is used in multiplication. In x³, x is the base and 3 is the exponent: x³ = x × x × x.

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Sources cited in the surrounding passage

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