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A detailed study of a PT-symmetric zero-dimensional quartic theory ispresented and a comparison between the properties of this theory and those of aconventional quartic theory is given. It is shown that the PT-symmetric quartictheory evades the consequences of the Mermin-Wagner-Coleman theorem regardingthe absence of symmetry breaking in d<2 dimensions. Furthermore, thePT-symmetric theory does not satisfy the usual Bogoliubov limit for theconstruction of the Green's functions because one obtains different results forthe $h\to0^-$ and the $h\to0^+$ limits.

PT-symmetric $\varphi^4$ theory in d=0 dimensions