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Equation 37 · Part 1 · How Fast Can a Horizon Learn Which Path You Took?

Symbol t_c

tct_c
tct_c

What this part means

the become irrevocable at an intermediate cutoff.

Its job in the formula

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

Where the article explains it

It does not answer how much information has become irrevocable at an intermediate cutoff tct_c .

The passage around this formula

The exponential calculation assumes that T labels a completed preparation–hold–recombination protocol. It does not answer how much information has become irrevocable at an intermediate cutoff tct_c . That distinction became unavoidable when Danielson, Kudler-Flam, Satishchandran, and Wald solved a finite-time optimization problem: given the entangling radiation already past a horizon cross-section, what future field purification best preserves Alice’s coherence? Their optimal future can be nonintuitive. Even after Alice has brought the branches together, reopening and manipulating the superposition can sometimes reduce the final decoherence [ 7 ] .

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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 surrounding passage

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