Here's the arXiv preprint: https://arxiv.org/abs/2009.04471 https://arxiv.org/abs/2009.04471 As I understand, they see a discrepancy between simulation and ob

Here's the arXiv preprint: https://arxiv.org/abs/2009.04471 https://arxiv.org/abs/2009.04471 As I understand, they see a discrepancy between simulation and observation of some lensing observables. Could be something wrong with the calculation of the observables, something wrong with the implementation of the simulations, or (the exciting bit) with the physics put into the simulations. As a complete non-expert on lensing observables and cosmological simulations, I'd guess it's one of the first two. As mentioned in the text, there are many other discrepancies between observations and simulations that are still unresolved. This adds to that list.