Symbol hatphi

The passage around this formula

…tolerance [ 10 ] . Whenever an edge’s own physical realization departs from plain node-to-node W -differencing in this way, the correct response is to model $s_e$ explicitly on that edge — not to let it distort the fitted $\hat\phi$ , and not to write it off as an unexplained curvature signal. The size of an uncorrected Sagnac term is worth putting a number to, because it is easy to underestimate. Take an illustrative closed network loop enclosing a continental-scale area of 2.5$\times$10^{11}\,$\mathrm{m^2}$ — a square…

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