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Equation 139 · Part 1 · The Entry a Relabeling Cannot Write

Symbol H_c

Hc(t)H_c(t)
HcH_c

What this part means

HcH_c 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

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

The passage around this formula

…the boundary between these two Hamiltonians: an observer who correctly computes UHfH_fU†U^\dagger — a legitimate operator identity, unchanged from the passive-relabeling case above — and then uses that operator, rather than Hc(t)H_c(t) , to predict or track the rotating frame’s own dynamics will find a discrepancy with no term in their own equations to explain it, on a clock the lab frame does not keep. The discrepancy is not missing energy. It is a dropped term whose physical origin is whatever classical control is…

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Learn the underlying idea

A subscript is a label attached below a symbol. It often selects a time step, component, category, or member of a sequence.

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Sources cited in the article section

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