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Equation 91 · Part 2 · The Atlas That Refuses to Close

subscript

AwA_w
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

introduced by Aharonov, Albert, and Vaidman as the quantity a weakly coupled pointer’s mean shift actually reports, to leading order in the coupling strength, once the postselection has been performed [ 11 ] . AwA_w is not an eigenvalue of A^\hat A , not an expectation value in the ordinary sense, and not guaranteed to be real: it is built from an amplitude ratio over a sub-ensemble selected by an event, the postselection, that has not yet happened at the time the weak coupling acts.

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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

These citations provide research context; check each source for the exact claim it supports.