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Large scale structure surveys are likely the next leading probe ofcosmological information. It is therefore crucial to reliably predict theirobservables. The Effective Field Theory of Large Scale Structures (EFTofLSS)provides a manifestly convergent perturbation theory for the weakly non-linearregime, where dark matter correlation functions are computed in an expansion ofthe wavenumber k over the wavenumber associated to the non-linear scale knl. Topush the predictions to higher wavenumbers, it is necessary to compute the2-loop matter power spectrum. For equal-time correlators, exactly as withstandard perturturbation theory, there are IR divergences present in eachdiagram that cancel completely in the final result. We develop a method bywhich all 2-loop diagrams are computed as one integral, with an integrand thatis manifestly free of any IR divergences. This allows us to compute the 2-looppower spectra in a reliable way that is much less numerically challenging thanstandard techniques. We apply our method to scaling universes where the linearpower spectrum is a single power law of k, and where IR divergences canparticularly easily interfere with accurate evaluation of loop corrections ifnot handled carefully. We show that our results are independent of IR cutoffand, after renormalization, of the UV cutoff, and comment how the methodpresented here naturally generalizes to higher loops.

The 2-loop matter power spectrum and the IR-safe integrand