Equation 103 · Part 1 · The Bit Comes Back Before the Bearing

Symbol F_Q

F_Q(t) \;\approx\; f_1\,\frac{t}{\beta}, \qquad t_G(\delta) \;\approx\; \frac{\beta}{f_1\,\delta^2}.

F_Q

What this part means

$F_Q$ 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

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

Full expressionSymbol F_QArticle meaning

The passage around this formula

a standard identity in quantum metrology [ 12 ] . Before scrambling, this is fixed by how the compass itself was built — a large, well-prepared gyroscope has a large charge variance and a small intrinsic uncertainty on its own heading. After scrambling, that fixed total has to be reconstructed piecemeal from radiation, and each individually emitted quantum, to the extent it is only weakly and independently correlated with g once the hole’s own state is traced over, contributes an addition to the total that adds like an independent sample rather than like a decoded codeword. This is the standard-quantum-limit regime of parameter estimation: for N independent, identically prepared probes each…

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