Equation 92 · Part 2 · The Entry a Relabeling Cannot Write

Symbol t

\Delta E_\Lambda(t) = \langle H_f\rangle - \langle H_S\rangle(t) = -\frac{\hbar\omega}{2}\cos(2gt).

t

What this part means

t is an argument of the function-like quantity on the left; its role is set by that function’s stated inputs.

Its job in the formula

t is an argument of the function-like quantity on the left; its role is set by that function’s stated inputs.

Full expressionSymbol tArticle meaning

The passage around this formula

the standard two-level exchange solution, exact for all t under this Hamiltonian. From it, $\langle$ $H_S$ $\rangle(t)$ = ( $\hbar$ $\omega$ /2)[ $\cos^2(gt)$ - $\sin^2(gt)$ ] = ( $\hbar$ $\omega$ /2) $\cos(2gt)$ , while $\langle$ $H_f$ $\rangle$ is exactly time-independent — a general fact for any state evolving under its own generator, not special to this one — and equal here to…

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Learn the underlying idea

A variable is a named place for a value. Its letter is a local label: x can mean position in one formula and a data point in another.

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Sources cited in the article section

[12] Circuit Quantum Electrodynamics ↗

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