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mattmatt321
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I'm doing quantum mechanics with only a little experience in linear algebra. I've been working on eigenstates/values/functions/whatever for a couple days but still having a little trouble. Here's a question I had recently, and if anyone can do a quick check of my work and point me in the right direction, I'd appreciate it.
The Hamiltonian operator for a system in 2-d vector space is iΔ(|w1><w2| - |w2><w1|). |w1> and |w2> are eigenstates of an observable operator Ω(hat).
The problem asks me to do a bunch of things:
1) Represent H(hat) and Ω(hat) in a matrix in the basis |w1>,|w2>.
2) Find the eigenvalues E1 and E2 and the normalized eigenstates |E1> and |E2>.
3) Express |w1> and |w2> as linear combinations of |E1> and |E2>.
4) Finally, use this linear combination to express H(hat) and Ω(hat) in the basis |E1>,|E2>.
Now, first I represented H(hat) as a matrix that looked like 0, iΔ (row 1) and -iΔ, 0 (row 2). I wasn't 100% sure how to do Ω(hat), but I figured the only non-zero values will be on the main diagonal, since we're representing it in the basis of its eigenstates.
Then, I solved for the eigenvalues and got E1 = -Δsqrt(2) and E2 = Δsqrt(2). This is the first area I got stuck -- I sort of "guessed" on how to get the eigenfunction from the eigenvalues. I think it involves solving a system of equations, but again, I'm pretty inexperienced with linear algebra.
In terms of making these eigenstates linear combinations of each other, I'm sure that means transform |w1> and |w2> into an additive combination of the new normalized eigenfunctions |E1>, |E2>. As long as I have |E1> and |E2> this seems straightforward enough.
So, I suppose if anyone can provide a straightforward method to transforming an eigenvalue into an eigenfunction and normalize it, it would be a huge help. Thanks for reading, and for all the help in the past.
EDIT: I guess this wasn't really a "quick" question in the end, sorry. But I feel like most of the helpers on PF can probably shed some light on this in about a sentence or two.
Homework Statement
The Hamiltonian operator for a system in 2-d vector space is iΔ(|w1><w2| - |w2><w1|). |w1> and |w2> are eigenstates of an observable operator Ω(hat).
Homework Equations
The problem asks me to do a bunch of things:
1) Represent H(hat) and Ω(hat) in a matrix in the basis |w1>,|w2>.
2) Find the eigenvalues E1 and E2 and the normalized eigenstates |E1> and |E2>.
3) Express |w1> and |w2> as linear combinations of |E1> and |E2>.
4) Finally, use this linear combination to express H(hat) and Ω(hat) in the basis |E1>,|E2>.
The Attempt at a Solution
Now, first I represented H(hat) as a matrix that looked like 0, iΔ (row 1) and -iΔ, 0 (row 2). I wasn't 100% sure how to do Ω(hat), but I figured the only non-zero values will be on the main diagonal, since we're representing it in the basis of its eigenstates.
Then, I solved for the eigenvalues and got E1 = -Δsqrt(2) and E2 = Δsqrt(2). This is the first area I got stuck -- I sort of "guessed" on how to get the eigenfunction from the eigenvalues. I think it involves solving a system of equations, but again, I'm pretty inexperienced with linear algebra.
In terms of making these eigenstates linear combinations of each other, I'm sure that means transform |w1> and |w2> into an additive combination of the new normalized eigenfunctions |E1>, |E2>. As long as I have |E1> and |E2> this seems straightforward enough.
So, I suppose if anyone can provide a straightforward method to transforming an eigenvalue into an eigenfunction and normalize it, it would be a huge help. Thanks for reading, and for all the help in the past.
EDIT: I guess this wasn't really a "quick" question in the end, sorry. But I feel like most of the helpers on PF can probably shed some light on this in about a sentence or two.
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