Recorded 25 March 2026. Gabriele Merlo of the Max Plank Institute for Software Systems presents "Multi-fidelity approach to the multiscale nature of plasma turbulence in stellarators" at IPAM's Multi-Fidelity Methods for Fusion Plasma Physics Workshop. Abstract: Fusion plasmas are paradigmatic examples of complex multiscale, multiphysics systems. This is particularly evident in the role of turbulence, which ultimately determines the energy confinement time of fusion devices and remains one of the key unsolved physics problems on the path toward a commercial fusion power plant. Addressing the multiscale nature of turbulence is therefore one of the central open challenges in fusion research, largely due to the enormous computational cost required to model these processes from first principles. In this talk, we will examine the role of cross-scale coupling in stellarators, a magnetic confinement configuration for which first-principles simulations have only very recently become feasible using the GENE code. We will discuss the importance of high-fidelity simulations and compare their results with those obtained from scale-separated, lower-fidelity models. Finally, we will explore strategies to further reduce model fidelity in a controlled manner, enabling the inclusion of cross-scale effects in routine applications such as profile predictions. Learn more online at: https://www.ipam.ucla.edu/programs/workshops/workshop-i-multi-fidelity-methods-for-fusion-plasma-physics/?tab=overview