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Equation 19 · Part 2 · The Bit Comes Back Before the Bearing

subscript

CtC_t
subscript

What this part means

The lower label selects a particular version, component, or indexed member of the quantity. For example, x₀ and xₜ can be values at different positions.

Its job in the formula

A subscript distinguishes a version, component, step, or member of a quantity. It does not automatically mean multiplication.

The passage around this formula

For the qubit, returned means: there exists a recovery channel R\mathcal R , built from quantum operations an agent holding both the full early radiation R and a further batch of radiation CtC_t collected up to time t can actually perform, whose entanglement fidelity to the identity channel on A is within ϵ\epsilon of perfect,

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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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