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--- probability-amplitude [June 13, 2026 at 03:47] – Ivan Janevski
+++ probability-amplitude [June 13, 2026 at 03:49] (current) – Ivan Janevski
@@ Line 2: / Line 2: @@
 **Probability amplitude** is a complex number associated with a possible outcome of a quantum measurement. The probability of that outcome is the squared modulus of the amplitude, a rule known as the [[born-rule|Born rule]].
-For a [[qubit]] $\lvert\psi\rangle = a\lvert 0\rangle + b\lvert 1\rangle$, $a$ is the amplitude for outcome 0 and $b$ is the amplitude for outcome 1:
+Classical probability uses real numbers in $[0, 1]$. Quantum mechanics uses complex numbers instead. The reason is interference: amplitudes can add or cancel before squaring, producing effects that no real-valued probability theory can describe.
-$$P(0) = |a|^2 \qquad P(1) = |b|^2$$
+For a [[qubit]] $\lvert\psi\rangle = a\lvert 0\rangle + b\lvert 1\rangle$, $a$ is the amplitude for outcome 0 and $b$ is the amplitude for outcome 1.
-Classical probability uses real numbers in $[0, 1]$. Quantum mechanics uses complex numbers instead. The reason is interference: amplitudes can add or cancel before squaring, producing effects that no real-valued probability theory can describe.
+$$P_0 = |a|^2 \qquad P_1 = |b|^2$$
 ## Normalization