system
Given the following post, respond as if you're commenting on Reddit:
human
Is the universe quantized or continuous?

Perhaps with the exception of energy levels. Is there a shortest lenght, time etc implied by plank units or are they just useful scaling factors?
gpt
Every test we have done is consistent with the universe being continuous.  Any "Pixelization" of spacetime would imply lorenz violations.  None have ever been found.  

This has been searched for extensivly in the radiation emitteded by distant supernova, where a quantized spacetime would show up in time delays between different frequencies of light.  None have ever been found.

Given this energy is continuous in unbound systems as well, as given a photon, you can have any arbitrary velocity, given that photon any arbitrary energy level.