Equation 137 · Part 2 · The Bend an Elevator Cannot Fake

Symbol y_1

y_2-y_1

y_1

What this part means

$\sqrt2$ \, $\sigma_y$ .

Its job in the formula

$y_1$ is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.

Full expressionSymbol y_1Article meaning

Where the article explains it

The combined noise on the independent-edge difference $y_2$ - $y_1$ is $\sqrt2$ \, $\sigma_y$ .

The passage around this formula

Take each edge’s fractional-frequency comparison uncertainty to be $\sigma_y$ = 1 $\times$ 10^{-18} , the stability optical clocks have already demonstrated is what centimetre-level geodesy requires [ 8 ] . The combined noise on the independent-edge difference $y_2$ - $y_1$ is $\sqrt2$ \, $\sigma_y$ . Setting signal equal to noise, $\phi_{,zz}$ \, $h^2$ = $\sqrt2$ \, $\sigma_y$ , gives

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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 surrounding passage

[8] Atomic Clock Performance Enabling Geodesy Below the Centimetre Level ↗

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