STRESS-ENERGY MUST BE SINGULAR ON THE MISNER SPACE HORIZON EVEN FOR AUTOMORPHIC FIELDS

We use the image sum method to reproduce Sushkov's result that for a m assless automorphic field on the initial globally hyperbolic region IG H of Misner space, one can always find a special value of the automorp hic parameter alpha such that the renormalized expectation value (alph a\T-ab\alpha) in the Sushkov state '(alpha\.\alpha)' (i.e. the automor phic generalization of the Hiscock-Konkowski state) vanishes. However, we shall prove by elementary methods that the conclusions of a recent general theorem of Kay, Radzikowski and Wald apply in this case. That is, for any value of cc and any neighbourhood N of any point b on the chronology horizon there exists at least one pair of non-null related points (x, x') is an element of (N boolean AND IGH) x (N boolean AND IGH) such that the renormalized two-point function of an automorphic f ield G(ten)(alpha)(x, x') in the Sushkov state is singular. In consequ ence (alpha\T-ab\alpha) (as well as other renormalized expectation val ues such as (alpha\phi(2)\alpha)) is necessarily singular on the chron ology horizon. We point out that a similar situation (i.e. singularity on the chronology horizon) holds for states on Gott space and Grant s pace.