They mention a GAN which is a generative model and currently no good measure of evaluation (beside metrics like Fréchet inception distance). The article only m

They mention a GAN which is a generative model and currently no good measure of evaluation (beside metrics like Fréchet inception distance). The article only mentions a qualitative comparison but no incorporation of causal / physic based-modeling that I would imagine would be important in astronomy. Easy enough for GAN to synthesize realistic, high-resolution images without any underlying model of reality / casuality.