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Equation 17 · Part 3 · Retrieval Is an Evidence System, Not a Memory

subscript

Zk(x)\mathcal{Z}_k(x)
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

Because retrieval and generation are separable, an end-to-end score is nearly uninformative about which one broke. Decompose it. Let Zk(x)\mathcal{Z}_k(x) be the retrieved set and S(x) the set of spans that would suffice to answer x :

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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

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