In this talk I will present some recent progress on the construction of ground state of the 2-dimensional Hubbard model, which is a prototypical model for studying phase transitions in quantum many-body system. Using fermionic cluster expansions and constructive renormalization theory, we proved that the ground state of the 2d Hubbard model on the honeycomb lattice with triangular Fermi surfaces is not a Fermi liquid in the mathematical precise sense of Salmhofer. I will also discuss the crossover phenomenon in the 2d square Hubbard model and universalities.
This talk relates to this first arXiv paper and this second arXiv paper.
This video was produced by the University of Münster, as part of the workshop Stochastic Analysis meets QFT – critical theory.
