Abstract
The φ4 theory in 1+d dimensions is analyzed at high temperatures in the imaginary-time formalism. General results are given for the leading high-temperature contributions to all renormalized Green’s functions. The latter are generated by a high-temperature partition function which describes another φ4 theory in d spatial dimensions with special mass renormalizations. The triviality/ nontriviality of the (φ4 )1+3 theory is discussed briefly.