Show thatddt-Ψ1*Ψ2dx=0

For any two solution to the Schrodinger equationΨ1 andΨ2 .

Short Answer

Expert verified

The solutions for Ψ1.and Ψ2is ddt-Ψ1*Ψ2dx=0

Step by step solution

01

Step 1: Define the Schrodinger equation

  • A differential equation that describes matter in quantum mechanics in terms of the wave-like properties of particles in a field.
  • Its answer is related to a particle's probability density in space and time.
02

Determine the solutions for Ψ1 and Ψ2.

ddt-Ψ1*Ψ2dx=-tΨ1*Ψ2dx=-Ψ2Ψ1*t+Ψ*1Ψ2tdx

But, from Schrodinger equation

Ψ2t=ih2m2Ψ2x2-ihVΨ2

And

Ψ1*t=-ih2m2Ψ2x2-ihVΨ1*

Thus,

localid="1658552483464" ddt-Ψ1*Ψ2dx=-(Ψ2[-ih2m2Ψ1*x2+ih]+Ψ1*[-ih2m2Ψ2x2+ih]VΨ2)dx=-ih2m-Ψ22Ψ1*x2-Ψ1*2Ψ2x2dx=-ih2m-Ψ22Ψ1*x2-Ψ1*2Ψ2x2dx=-ih2m-xΨ2Ψ1*x-Ψ1*Ψ2xdxddt-Ψ1*Ψ2dx=-ih2m(Ψ2Ψ1*x-Ψ1*Ψ2x)

Where this must equal zero because Ψ1.and Ψ2are normalized.

Hence, the solutions for Ψ1.and Ψ2isddt-Ψ1*Ψ2dx=0

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At time t = 0 a particle is represented by the wave function

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