Lost in Latent Space: An Empirical Study of Latent Diffusion Models for
  Physics Emulation
Authors: name: François Rozet; name: Ruben Ohana; name: Michael McCabe; name: Gilles Louppe; name: François Lanusse; name: Shirley Ho
Published: 2025-07-03 13:32:50

Abstract: The steep computational cost of diffusion models at inference hinders their
use as fast physics emulators. In the context of image and video generation,
this computational drawback has been addressed by generating in the latent
space of an autoencoder instead of the pixel space. In this work, we
investigate whether a similar strategy can be effectively applied to the
emulation of dynamical systems and at what cost. We find that the accuracy of
latent-space emulation is surprisingly robust to a wide range of compression
rates (up to 1000x). We also show that diffusion-based emulators are
consistently more accurate than non-generative counterparts and compensate for
uncertainty in their predictions with greater diversity. Finally, we cover
practical design choices, spanning from architectures to optimizers, that we
found critical to train latent-space emulators.