From few- to many-body quantum physics

Experiments with cold atoms can be performed with a controllable number of particles, which motivates exploring how quantum systems transition from being few-body to becoming many-body. Taking the half-filling case as a reference to the many-body limit, we investigate how static and dynamic properties of one-dimensional quantum systems approach this limit as the number N of particles increases from 1. Our results indicate that for N as small as 4, several properties seem already very similar to those observed at half-filling. Before reaching this point, however, the results are highly dependent on N.