This might be more fit in physicsSE, but since I don't even know if my premise is physically sound, I'll post it here.
One day, something caused the universe to get mirrored, meaning a left-right swap, relative to any arbitrary view point. Let's ignore how this is done, how it's possible to move things over more distance than the observable universe in an instant etc., I only care about before and after.
The laws of physics are not affected by this, it's just a change in location and orientation for all particles, energy and so on.
Let's say you already suspected that this might happen one day (for whatever reason), so you're regularly doing some kind of test that should change its result after the universe got mirrored.
What kind of test could this be? What kind of experiment would give a different result in a mirrored universe?
My own ideas so far:
- Of course you wouldn't just see everything being mirrored, since your eyes, brain and so on also got mirrored.
- There are some molecules that only work the way they do in one orientation and not if mirrored, but in the mirrored universe, everything they react with would be mirrored as well, so there should be no difference.
- There is the Lorentz force which can create a circular electric field (or was it magnetic?) from a straight motion, but it goes the opposite direction when the charge is opposite. This might be a good candidate. Is enough known about electrons and other charged particles to know whether they would get an opposite charge if they got mirrored? I know that there is always an anti-particle with opposite charge, maybe that is exactly this? I've also heard about theories that this means that it travels backwards in time, but I haven't looked much into that so far. Could this reverse time travel (if that's even what it is) cause some side effects if the universe is mirrored?
Related questions: I've seen some questions that ask about interactions between a normal and a mirrored universe, the answers to those always come down to doing something on the border. In my case, there is no such border, except in time. And you can't do experiments in an infinitesimally short timespan.