Quantum Matter Lecture 18

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okay let pick up where we left off last time talking about Fermi liquid theory so I gonna use a couple of results that we derived at the end of last lecture so let me just remind you what they were first of all we derived the energy of a quasi particle at momentum P and spin Sigma that that we can write as the the energy without interacting with other other quasi particles so this quantity here is VF star times P minus P F where V F star is is P F over m star with FM start being a phenomenological factor and then we have the interaction P prime Sigma prime have Sigma Sigma prime P comma P prime Delta n oops move myself another way there Delta n of P prime Sigma prime so all the peas being vectors here I guess the the point here being the energy of a quasi particle at momentum P is shifted by the presence of quasi particles with momentum P prime the important assumption of land up for me liquid theory is that the presence of other quasi particles can shift your ship the energy of a quasi particle