Why it's impossible to prove that we don't live in a simulation
If the crowd at the American Museum of Natural History's sold out 2016 Isaac Asimov Memorial Debate hoped for a conclusive answer to the topic question - "Is the Universe a Simulation?" - they were out of luck.
While everyone on the panel - consisting of three theoretical physicists, one cosmologist, and one philosopher, plus host Neil deGrasse Tyson - came to different conclusions when estimating how likely it is that the universe is nothing more than a simulation, no participant thought we could know for sure (though physicist Lisa Randall said she thought the chances were so low as to be "effectively zero").
It turns out that it's impossible to prove that the universe is "real" and not a simulation, according to panelist David Chalmers, a professor of philosophy at New York University.
"We're not going to get conclusive proof that we're not in a simulation, because any proof would be simulated," Chalmers pointed out.
We can try and figure out if physics and math give us reasons to believe that yes, the universe is simply a simulation: a computer program being run by some higher being. Some members of the panel conduct research with that in mind, trying to see if the mathematical rules that govern the universe can be perfectly replicated. If they can, that indicates that it's at least possible to simulate a universe.
But it's impossible to trust evidence that tells us that the universe is not a simulation, because if it were simulated, it could be programmed to provide evidence convincing us that it's not.
Huh.