This might sound silly... I was on a travel, and arrived late at my class of Quantum Mechanics 2. The proffesor was in the middle of a disscusion, and I'm trying to figure what was it. I asked one of my classmates and said he was talking about something with Projection operators. He was discussing a problem of a system with two states, and then started to discuss a system of three states, two states with strong interaction, and another one of less interaction (???).(adsbygoogle = window.adsbygoogle || []).push({});

-------------- (P)

--------------

-------------- (Q)

He then defined:

[tex] P = \left(\begin{array}{ccc}1 & 0 & 0 \\ 0 & 0 & 0 \\ 0 & 0 & 0 \end{array}\right)[/tex]

[tex] Q = \left(\begin{array}{ccc}0 & 0 & 0 \\ 0 & 1 & 0 \\ 0 & 0 & 1 \end{array}\right)[/tex]

All seems to get down to claculate P G(z) P

Anyway, I wont see the professor untill next thursday. If someone can figure out the topic so I can start studying to get up to date this weekend, I will appreciate it.

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# Need help Figuring out the topic

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