A couple of months ago, we reported that a team of physicists were going to see if The Matrix were more real than meets the eye - well, we've gotten a little further now and another team of physicists have found another way to experiment if we're all living within a computer.

There has been a philosophical thought experiment that has for quite some time shown that it is more likely that we're actually living in a machine - yes, that the real world is not so "real". This theory goes onto a path that any civilisation which would get as far as a 'post-human' stage would end up with the ability to run simulations on the scale of a universe. Considering the scale of what is out there, billions of stars, suns, worlds, and more - it is not only possible, but it is likely that it has already happened.
Then we tumble further down the rabbit hole, and it is statistically possible that we're (the human race, our universe) is within a chain of simulations within simulations. Inception springs to mind, so does The Matrix. The alternative to this is that we are the first civilisation, within the first universe - and this is virtually impossible.
A new team is starting the experiments, with Professor Martin Savage at the University of Washington saying that our own computer simulations are only capable of modelling a universe on the scale of an atom's nucleus, and that there are already "signatures of resource constraints", which could tell us if larger models are possible. Savage has said that computers used to build simulations perform "lattice quantum chromodynamics calculations" - which divide space into a four-dimensional grid.
Doing this allows researchers to look into the force which binds subatomic particles together into neutrons and protons, but also allows other things to happen within the simulation itself. This includes the development of complex physical "signatures", something the researchers don't program directly into the computer. While on the look out for these signatures, such as limitations on the energy held by cosmic rays, they hope to find similarities within our own universe.
What happens if signatures appear in both? Well, we could possible be living within a computer simulation. Savage told the University of Washington news service:
If you make the simulations big enough, something like our universe could emerge.
The scary thing is, if they did find out we're all living within a computer simulation - would we ever be told? That would really spin the heads of religious people, believing we are God's creation - what if we are the creation of a simulation, a real-time artificial intelligence system that allows us to grow, and procreate just like a plant or animal? How mind-blowing!