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σy=1×10−18\sigma_y = 1\times10^{-18}

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Take each edge’s fractional-frequency comparison uncertainty to be σy\sigma_y = 1×\times10^{-18} , the stability optical clocks have already demonstrated is what centimetre-level geodesy requires [ 8 ] . The combined noise on the independent-edge difference y2y_2-y1y_1 is 2\sqrt2\,σy\sigma_y . Setting signal equal to noise, ϕ,zz\phi_{,zz}\,h2h^2 = 2\sqrt2\,σy\sigma_y , gives

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σy\sigma_y

Symbol sigma_y

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

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σy=1×10−18\sigma_y = 1\times10^{-18}

Equation 136 · 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.

Take each edge’s fractional-frequency comparison uncertainty to be σy\sigma_y = 1×\times10^{-18} , the stability optical clocks have already demonstrated is what centimetre-level geodesy requires [ 8 ] . The combined noise on the independent-edge difference y2y_2-y1y_1 is 2\sqrt2\,σy\sigma_y . Setting signal equal to noise, ϕ,zz\phi_{,zz}\,h2h^2 = 2\sqrt2\,σy\sigma_y , gives

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