The GW approximation in many-body perturbation theory is the state of the art method for computing theoretical photoemission spectra in moderately sized systems. For weakly- to moderately-correlated systems, GW can now be applied to systems with hundreds (or thousands!) of atoms and gives good agreement with experimental photoemission spectra.

Even though it is already very successful, there is still room to push GW to even larger systems and/or improve the predictive accuracy of GW. The exascale computing frontier is fast approaching, and GW goes large-scale (GW-XL) is a workshop meant to share ideas to prepare for this computing milestone. Applications of GW, large- or small-scale, are also welcome to contribute to the program. Topics for the workshop include (but are not limited to):

Numerical and algorithmic developments

Prefactor reduction, scaling reduction, parallelization algorithms, and other numerical aspects of GW calculations.