QuestionJune 6, 2025

A wave function can be expanded in basis states as vert psi rangle =sum _(n)a_(n)vert psi _(n)rangle What must be true of the expansion coefficients? sum _(n)vert a_(n)vert ^2=1 They must be real numbers. There is no restrictions on the coefficients. sum _(n)a_(n)=1

A wave function can be expanded in basis states as vert psi rangle =sum _(n)a_(n)vert psi _(n)rangle What must be true of the expansion coefficients? sum _(n)vert a_(n)vert ^2=1 They must be real numbers. There is no restrictions on the coefficients. sum _(n)a_(n)=1
A wave function can be expanded in basis states as
vert psi rangle =sum _(n)a_(n)vert psi _(n)rangle 
What must be true of the expansion coefficients?
sum _(n)vert a_(n)vert ^2=1
They must be real numbers.
There is no restrictions on the coefficients.
sum _(n)a_(n)=1

Solution
4.6(231 votes)

Answer

\sum _{n}\vert a_{n}\vert ^{2}=1 Explanation 1. Understand the wave function expansion The wave function \vert \psi \rangle is expressed as a linear combination of basis states \vert \psi _{n}\rangle with coefficients a_{n}. 2. Apply normalization condition For a quantum state, the probability interpretation requires that the sum of the squares of the absolute values of the coefficients equals 1: **\sum _{n}\vert a_{n}\vert ^{2}=1**. 3. Evaluate other conditions Coefficients do not need to be real numbers; they can be complex. There is no requirement for \sum _{n}a_{n}=1, as this does not relate to normalization or probability conservation.

Explanation

1. Understand the wave function expansion<br /> The wave function $\vert \psi \rangle$ is expressed as a linear combination of basis states $\vert \psi _{n}\rangle$ with coefficients $a_{n}$.<br /><br />2. Apply normalization condition<br /> For a quantum state, the probability interpretation requires that the sum of the squares of the absolute values of the coefficients equals 1: **$\sum _{n}\vert a_{n}\vert ^{2}=1$**.<br /><br />3. Evaluate other conditions<br /> Coefficients do not need to be real numbers; they can be complex. There is no requirement for $\sum _{n}a_{n}=1$, as this does not relate to normalization or probability conservation.
Click to rate:

Similar Questions