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Equation 1 · Part 7 · How Fast Can a Horizon Learn Which Path You Took?

subscript

∣Ψ(0)⟩=∣0⟩+∣1⟩2⊗∣hin⟩.|\Psi(0)\rangle= \frac{|0\rangle+|1\rangle}{\sqrt 2}\otimes|h_{\rm in}\rangle .
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

Begin with an equal superposition of two localized alternatives, ∣Ψ(0)⟩=∣0⟩+∣1⟩2⊗∣hin⟩|\Psi(0)\rangle= \frac{|0\rangle+|1\rangle}{\sqrt 2}\otimes|h_{\rm in}\rangle . The labels zero and one denote paths, not energy eigenstates. After the system’s long-range field interacts with the inaccessible degrees of freedom, an idealized final pure state has the form

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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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