Casimir squared correction to the standard rotator Hamiltonian for the O(n) sigma-model in the delta-regime
Casimir squared correction to the standard rotator Hamiltonian for the O(n) sigma-model in the delta-regime
In a previous paper we found that the isospin susceptibility of the O($n$) sigma-model calculated in the standard rotator approximation differs from the next-to-next to leading order chiral perturbation theory result in terms vanishing like $1/\ell\,,$ for $\ell=L_t/L\to\infty$ and further showed that this deviation could be described by a correction …