phy-4600/lecture_notes/4-13/overview

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2016-04-28 20:51:34 +00:00
Exam 2 Problem 2
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(pic) Finished the problem using the boundary conditions
boundary conditions limit the number of possible spherical harmonics.
Two Similar Particles
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❙a,b❭ = ❙a❭⊗❙b❭
Exchange Operator
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𝓟₁₂❙a,b❭ = ❙a,b❭
𝓟₁₂(❙a❭⊗❙b❭) = ❙b❭⊗❙a❭
If particles are indistinguishable
𝓟₁₂❙a,b❭ = exp(iδ) ❙a,b❭ = λ ❙a,b❭
𝓟²₁₂❙a,b❭ = λ² ❙a,b❭ = ❙a,b❭ ⇒ λ=±1
Symmetry States
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(pic) Two cases: symmetric, antisymmetric
Symmetric States, λ=1
𝓟₁₂❙a,b❭
(pic) Constructed the exchange operator in matrix form, then found eigen states
(pic) Showed that the exchange operator leads to the Pauli Exclusion Principle