We revisit and extend Fisher's argument for a Ginzburg-Landau description of multicritical
Yang-Lee models in terms of a single boson Lagrangian with potential $\varphi^ 2 (i\varphi)^
n $. We explicitly study the cases of $ n= 1, 2$ by a Truncated Hamiltonian Approach based
on the free massive boson perturbed by $\boldsymbol P\boldsymbol T $ symmetric
deformations, providing clear evidence of the spontaneous breaking of $\boldsymbol
P\boldsymbol T $ symmetry. For $ n= 1$, the symmetric and the broken phases are …

We revisit and extend Fisher's argument for a Ginzburg-Landau description of multicritical
Yang-Lee models in terms of a single boson Lagrangian with potential φ2 (iφ) n. We
explicitly study the cases of n= 1, 2 by a Truncated Hamiltonian Approach based on the free
massive boson perturbed by PT symmetric deformations, providing clear evidence of the
spontaneous breaking of PT symmetry. For n= 1, the symmetric and the broken phases are
separated by the critical point corresponding to the minimal model M (2, 5), while for n= 2 …