PATHOLOGICAL BEHAVIOR OF RENORMALIZATION-GROUP MAPS AT HIGH FIELDS AND ABOVE THE TRANSITION-TEMPERATURE

We show that decimation transformations applied to high-q Potts models result in non-Gibbsian measures even for temperatures higher than the transition temperature. We also show that majority transformations ap plied to the Ising model in a very strong field at low temperatures pr oduce non-Gibbsian measures. This shows that pathological behavior of renormalization-group transformations is even more widespread than pre vious examples already suggested.