- #1
wondering12
- 18
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Hi,
The following textbook Heisenberg's Quantum Mechanics shows an example of calculating Berry's curvature (top page on pg 518). It led to a following equation
Vm= (- 1/B2 ) * i *∑ ( <m,B|S|n,B> ∧ <n,B|S|m,B> ) / A2 ...[1]
the textbook claims that we add the term m = n since <m|S|m> ∧ <m|S|m> = 0 then the above equation simplifies to
Vm= (- 1/B2 ) * i * ∑( <m,B|S ∧ S|n,B> ) / A2....[2]
The symbol ∧ stands for 'and' in logic or cross product.
My question is how the author derived that claim and how it led to that equation [2] from equation [1] ?
My reasoning is that |n,B> 'and' <n,B| are both true therefore ( |n,B> 'and' <n,B|) = 1 which is equal to 1 'and' 1 however I do not believe that my reasoning is a valid one. What is the alternative to this?
Thanks.
The following textbook Heisenberg's Quantum Mechanics shows an example of calculating Berry's curvature (top page on pg 518). It led to a following equation
Vm= (- 1/B2 ) * i *∑ ( <m,B|S|n,B> ∧ <n,B|S|m,B> ) / A2 ...[1]
the textbook claims that we add the term m = n since <m|S|m> ∧ <m|S|m> = 0 then the above equation simplifies to
Vm= (- 1/B2 ) * i * ∑( <m,B|S ∧ S|n,B> ) / A2....[2]
The symbol ∧ stands for 'and' in logic or cross product.
My question is how the author derived that claim and how it led to that equation [2] from equation [1] ?
My reasoning is that |n,B> 'and' <n,B| are both true therefore ( |n,B> 'and' <n,B|) = 1 which is equal to 1 'and' 1 however I do not believe that my reasoning is a valid one. What is the alternative to this?
Thanks.