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Equation 6 · Part 1 · The Entry a Relabeling Cannot Write

Symbol H_f

Hf\mathcal H_f
HfH_f

What this part means

HfH_f 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

HfH_f 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

three Hermitian terms, each in units of energy: the system’s own generator, the bath’s own generator, and an interaction coupling the two. A fine state is a density operator ρ\rho on Hf\mathcal H_f — trace one, positive semidefinite, dimensionless as a probability object.

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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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