= Gravitational redshift measured by a computation counter
{c}
{title2=$\Delta N\simeq f_{\rm op}\tau\,g\Delta h/c^2$}
Two identical stationary devices counting operations at the same rate per <proper time> act as <clocks>. If the upper one sends start and finish light signals over a fixed path to the lower one in a stationary <metric>, both propagation delays are identical in <coordinate time> and cancel from the interval comparison. The lower elapsed <proper time> divided by the upper one is $\sqrt{g_{tt}(r_2)/g_{tt}(r_1)}$. In the weak field the relative lag is $g\Delta h/c^2$, giving the displayed operation deficit. A rate of $10^{12}$ operations per second, a week and a height difference of ten metres give a deficit of roughly $660$ operations. This observable tests the radial <clock>-rate factor; it does not independently determine the radial spatial <metric> coefficient because the common signal delay cancels.
Back to article page
