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ϕ(x):=ln⁡U(x)\phi(\mathbf x) := \ln U(\mathbf x)

Why this formula appears here

For a static observer at position x\mathbf x in a stationary spacetime, define U(x\mathbf x) := dτ\tau/dt , the local rate of proper time relative to coordinate time. Two clocks compared through any phase-coherent link that depends only on their respective proper frequencies report the ratio νj\nu_j/νi\nu_i = U(xj\mathbf x_j)/U(xi\mathbf x_i) — a fact about stationary spacetimes that follows from the timelike Killing vector generating t -translations, and one on which the standard treatments of relativity in a geodetic or navigational setting already rely [ 10 , 14 ] . The dependence on endpoints only, never on the path connecting them, is not an approximation: because ∂\partial/∂\partial t generates a…

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Published contexts (1)

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ϕ(x):=ln⁡U(x)\phi(\mathbf x) := \ln U(\mathbf x)

Equation 11 · Evolutionary Physics

The Bend an Elevator Cannot Fake

This equation states an equality: the expressions on both sides have the same value under the article’s assumptions.

For a static observer at position x\mathbf x in a stationary spacetime, define U(x\mathbf x) := dτ\tau/dt , the local rate of proper time relative to coordinate time. Two clocks compared through any phase-coherent link that depends only on their respective proper frequencies report the ratio νj\nu_j/νi\nu_i = U(xj\mathbf x_j)/U(xi\mathbf x_i) — a fact about stationary spacetimes that follows from the timelike Killing vector generating t -translations, and one on which the standard treatments of relativity in a geodetic or navigational setting already rely [ 10 , 14 ] . The dependence on endpoints only, never on the path connecting them, is not an approximation: because ∂\partial/∂\partial t generates a…

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