Equation 120 · Part 1 · The Bend an Elevator Cannot Fake

Symbol y_1

y_1 = \phi(0)-\phi(-h)

y_1

What this part means

$\sqrt2$ \, $\sigma_y$ .

Its job in the formula

$y_1$ is part of the quantity the equation computes from the expression on the right.

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

An exact analytic evaluation, not a simulation, fixes the scale this actually requires. Take three clocks stacked vertically at heights -h , 0 , and +h near Earth’s surface, giving two edges $y_1$ = $\phi(0)$ - $\phi(-h)$ and $y_2$ = $\phi(h)$ - $\phi(0)$ . Their difference is an exact finite-difference identity up to a Taylor remainder of order $h^4$ :

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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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