Charalampos Anastasiou, ETH Zürich, [HET Seminar], A Numerical Approach to Perturbative Computations from the LHC to the Large Scale Structure

Thursday 28 Aug 2025, 11:00 → 12:00 US/Eastern

Small Seminar Room (https://bnl.zoomgov.com/j/1605506805?pwd=AA9rwL4hM5AwG2b0zEwDdXjzhvJjSz.1)

High-precision theoretical predictions are essential for interpreting data from both the LHC experiments and cosmological surveys of the Large Scale Structure (LSS). These predictions rely on perturbative computations at high orders which are plagued by ultraviolet and infrared  singularities, posing significant challenges for purely analytic methods. In this talk, I will present a numerical framework designed to tackle these calculations in both domains. The core of our method is the local subtraction of all singularities at the integrand level, which renders loop integrals suitable for efficient and direct numerical integration. I will demonstrate the potential of this approach with recent results, including the calculation of the two-loop power spectrum in the Effective Field Theory of LSS for cosmology, and its application to multi-loop amplitudes for electroweak processes at the LHC.