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Equation 69 · Part 1 · The Bend an Elevator Cannot Fake

Symbol hatphi

ϕ^\hat\phi
ϕ^\hat\phi

What this part means

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

Its job in the formula

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

The passage around this formula

The deeper question the loop-closure argument sets aside is what happens once loop closure has already been confirmed — once a single, well-behaved ϕ^\hat\phi genuinely fits every edge. Does a nonzero slope in that fitted potential mean anything has curved? The equivalence principle’s oldest thought experiment already answers no, and the answer can be made exact rather than qualitative.

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Learn the underlying idea

A variable is a named place for a value. Its letter is a local label: x can mean position in one formula and a data point in another.

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Sources cited in the article section

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