Equation 98 · Part 3 · The Atlas That Refuses to Close

Symbol psi

\langle f|\sigma_z|\psi\rangle = \tfrac12(1+i)

\psi

What this part means

psi is part of the quantity the equation computes from the expression on the right.

Its job in the formula

psi is part of the quantity the equation computes from the expression on the right.

Full expressionSymbol psiArticle 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 variable is a named place for a value. Its letter is a local label: x can mean position in one formula and a data point in another.

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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 ↗

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