Equation 99 · Part 2 · The Atlas That Refuses to Close

subscript

\sigma_z

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.

Full expressionsubscriptArticle meaning

The passage around this formula

1 ( ∣ ↑ ⟩ + i ∣ ↓ ⟩) . Then $\langle$ f| $\psi$ $\rangle$ = $\tfrac12(1-i)$ and $\langle$ f| $\sigma_z$ | $\psi$ $\rangle$ = $\tfrac12(1+i)$ , so the weak value of $\sigma_z$ is

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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.

Open the illustrated subscripts: which member of a family? guide →

Sources cited in the article section

[11] How the Result of a Measurement of a Component of the Spin of a Spin-1/2 Particle Can Turn Out to Be 100 ↗

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