I don’t know how seriously other scientists will take this, but according to this article at Phys.org, physicists at the University of Bonn believe they can develop a test that will accurately measure whether or not we are a bunch of brains in a vat. Or just one one brain in a vat. The test would depend upon our understanding of something called quantum chromodynamics, a field of study concerned with the way elementary particles are bound together by different forces.
Anyone with a thorough understanding of high energy physics can check the paper out on the arXiv website. If you can make anything of it, please don’t be afraid to leave a comment. In the meantime, I have to wonder at the idea that this is testable at all. As the Phys.org article notes,
… any conclusions resulting from such work would be limited by the possibility that everything we think we understand about quantum chromodynamics, or simulations for that matter, could be flawed.
The data this test would return would have to be checked against a simulation, unless I’m missing an important fact and there’s something else to check the data against. If that’s the case, we run into the same problem everybody else has run into when pondering this question: how do I know my experiences or my data adequately represent whatever “reality” is “out there?” And if the answer is something like “we have mathematical models that tells us what we should find,” how do we test whether those mathematical models are accurate or reliable?
If all I’ve experienced is this thing that we’re calling a simulation, what can I know about an existence that isn’t a simulation? These are pretty elementary philosophical questions—but none of them have been answered, which is why this article had me raising my eyebrows.
The conceptual setup here is another reason I’m skeptical. It’s not that I don’t understand the concepts (I think I do to a small degree), it’s that I don’t think they’re very clear. That may be the article’s fault more than the scientist’s, but I’m still left wondering how they’d get around some pretty fundamental problems. For instance, what are the simulations they are using simulations of? If I devise a simulation for reality that demands particular results, and then I find that those results match what I see in reality, why should I conclude that reality is a simulation? Why not conclude the opposite and say that I’ve devised a very good simulation of what’s “real?” I get the feeling a lot of this could be cleared up by someone who understands the kinds of simulations they’re talking about, but until I can get a grasp on that, I’m left to wonder.
There’s also a problem of consciousness. My existence is so caught up in the concepts of reality and simulation that I can’t imagine a way to untangle the two. What I mean is that the idea of simulation only seems meaningful from a conscious subject’s point of view. Is it possible this test somehow accounts for consciousness? Is it even possible to think about the difference between reality and simulation without a clear sense of what a conscious subject is?
I know I’m jumping all over the place, but this little article brought up all sorts of questions, and I haven’t thought about these kinds of problems in a long time. As it stands, I can’t help but be skeptical. Not about my existence, but about that test.