We consider a system ofNbosons, in the two-dimensional unit torus. We assume particles to interact through a repulsive two-body potential, with a scattering length that is exponentially small inN(Gross–Pitaevskii regime). In this setting, we establish the validity of the predictions of Bogoliubov theory, determining the ground state energy of the Hamilton operator and its low-energy excitation spectrum, up to errors that vanish in the limit\documentclass[12pt]{minimal}
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				\begin{document}$$N \rightarrow \infty $$\end{document}N→∞.