However, it was not clear how to do a continuation from d = 2 + ϵ ϵ to d = 4 dimensions as the calculations relied on the smallness of the expansion parameter ϵ ϵ . The computational methods for a nonperturbative treatment were not at hand by this time. For this reason the idea of asymptotic safety in quantum gravity was put aside for some years. Only in the early 90s, aspects of 2 + ϵ ϵ dimensional gravity have been revised in various works, but still not continuing the dimension to four.