The question of whether we actually live in a simulation was first put forth by University of Oxford philosophy professor Nick Bostrom in 2003. In a follow-up 2006 article, he said there was probably no way to know for certain.
There is, apparently, no red pill, as in "The Matrix." Or is there?
University of Washington physics professor Martin Savage feels there is a way to determine if we exist in a simulation. In the paper, "Constraints on the Universe as a Numerical Simulation," he and graduate student Zohreh Davoudi propose looking for a "signature," or pattern, in the universe that also occurs in current small-scale computer simulations.
... supercomputers capable of creating a simulation of the universe would be hobbled by finite resources, and one way we might be able to detect those limits is to look for cosmic rays that don't travel the way they would be expected to travel.The paper concludes by saying,
There always remains the possibility for the simulated to discover the simulators.Despite writing the paper, Savage isn't particularly concerned that he may, in fact, be living in a computer simulation. Laughing, he said,
I don't stay up at night worrying about it.We wouldn't either, unless we are actually coppertop batteries being used by The Matrix.