2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/58416According to a formula that was put forward many decades ago the ground state energy per particle of an interacting, dilute Bose gas at density $ρ$ is $2π\hbar^2ρa/m$ to leading order in $ρa^3\ll 1$, where $a$ is the scattering length of the interaction potential and $m$ the particle mass. This result, which is important for the theoretical description of current experiments on Bose-Einstein condensation, has recently been established rigorously for the first time. We give here an account of the proof that applies to nonnegative, spherically symmetric potentials decreasing faster than $1/r^3$ at infinity.A few corrections to Eqs. 3.21 and 3.33--3.36 in the printed version have been madeMathematical PhysicsCondensed Matter81V70, 35Q55, 46N50text