Castilla elastica Castilla elastica Castilla elastica, the Panama rubber tree, is a tree native to the tropical areas of Mexico, Central America, and northern South America. It was the principal source of latex among the Mesoamerican peoples in pre-Columbian times. The latex gathered from "Castilla elastica" was converted into usable rubber by mixing the latex with the juice of the morning glory species "Ipomoea alba" which, conveniently, is typically found in the wild as a vine climbing "Castilla elastica". The rubber produced by this method found several uses, including most notably, the manufacture of balls for the Mesoamerican ballgame "ōllamaliztli". The Aztec
Fermi liquid theory involve, e.g., a change in the effective mass of particles. The quadratic terms correspond to a sort of "mean-field" interaction between quasiparticles, which is parametrized by so-called Landau Fermi liquid parameters and determines the behaviour of density oscillations (and spin-density oscillations) in the Fermi liquid. Still, these mean-field interactions do not lead to a scattering of quasi-particles with a transfer of particles between different momentum states. The renormalization of the mass of a fluid of interacting fermions can be calculated from first principles using many-body computational techniques. For the two-dimensional homogeneous electron gas, GW calculations and quantum Monte Carlo methods