e introduce a new non-perturbative method suitable for analyzing scalar quantum field theories at strong coupling based on mapping between quantum field theories in $dS_{D}\times M_{N}$ spacetime and statistical field theories in Euclidean space $M_{N}$. Applying this method to $\lambda\phi^{4}$ theory in $dS_{D}\times E_{4}$ spacetime, we analyze behavior of the 4-dimensional $\lambda\phi^{4}$ theory in the regime $\lambda\sim{}1$ and give a new argument in favor of triviality of the theory.