Does Fermi liquid theory apply to He3 ?

8 Does Market Theory Apply to Biology ?

Traditionally, market models in economics describe interactions in which the commodities traded are subject to complete contracts that are enforceable at no cost. Such contracts do not exist among other animals. In conventional economic models, there is also no account of who meets whom, what the traders know, and how they settle on a transaction, whereas these aspects play a major role in biol...

Fermi Liquid Theory: Principles

Landau developed the idea of quasiparticle excitations in the context of interacting Fermi systems. His theory is known as Fermi liquid theory. He introduced the idea phenomenologically, and later Abrikosov and Kalatnikov gave a formal derivation using diagrammatic perturbation theory to all orders. Landau suggested describing the excited states of the interacting system as in one-to-one corres...

Fermi Liquid Theory: Thermodynamics

I have chosen to use a spin notation of “up” or “down” with respect to a convenient z axis rather than a more rotationally invariant formulation. The quantity εp is not the same as in the interacting system, but can be expanded in the same way about p = pF εp = εF + vF (p − pF )+ · · · (3) where εF , vF are not the same as in the noninteracting system. The single quasiparticle energy does not d...

Quantum phase transitions and Fermi liquid theory

Functional Integral approach to quasi-particles in Fermi liquid theory

In this paper we propose a new way of organizing many-body perturbation theory in the Path-integral formulation where a set of quasi-particle wavefunctionals ψ’s are introduced and are identified with quasi-particles in Landau Fermi liquid theory. We show how Fermi liquid theory can be obtained through ψ’s in this new framework of perturbation theory, where the only assumption is adiabaticity b...