system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: How the experiments to test if our universe is a simulation work.
gpt
You can't really test this. The universe as we know it does what it does; what's behind it has no bearing on anything we can measure from within.

People have put some arguments forward. Say, when we simulate a little part of the universe on our computers, our calculations aren't 100% exact. Things can snap to a fine grid and such. If you lived in a large version of that simulation, you could potentially measure those artifacts. Maybe even build a pretty good model implicating something looking like the simulation code. Maybe it's just what the 'real' universe does. Who knows. But if those artifacts seem arbitrary, as if to fit a computer, maybe that is in fact what's going on.

Another argument is that of simulated worlds being more numerous. It only takes one simulated universe per 'real' universe to be on par. There are likely to be more. Then if you are randomly dropped into one of the universes, it's more likely to be a simulated one because there are more of them.

In the end it's unknowable, though. All we see is our own universe, be it 'real' or simulated. We can only investigate how our universe works. Anything beyond it is speculation. How do you even determine what's real? This universe certainly is real to us no matter what.