Amazing stuff! I have wondered/speculated myself multiple times for several decades if not the universe is an aquarium created by some intelligent beings. See e.g. my 2020 blog post here. I blogged here in late October about a research paper that claimed to have a mathematical proof of impossibility of a computer simulation.
Has somebody already verified the proof for this mathematical framework?
How can a universe like ours be defined mathematically beyond physics? The study is from the perspective of computer science according to the title. This is a serious limitation, because we do not know what other intelligent beings are capable of!
The second serious limitation is that the author assumes the simulation is run by humans.
In my opinion, it is not clear from the abstract of this paper what the conclusion of the researcher is if any. Remains kind of nebulous!
The author David H. Wolpert has accumulated 47166 citations over his lifetime covering about 400 publications (great, but not impressive unless he is a niche researcher). However, about 63% of all citations are attributed to only two of his papers he published in 2002 and 1992. This professor is perhaps not exactly an Albert Einstein.
Caveat: I did not read the paper.
"The simulation hypothesis — the idea that our universe might be an artificial construct running on some advanced alien computer — has long captured the public imagination."
"The simulation hypothesis — the idea that our universe might be an artificial construct running on some advanced alien computer — has long captured the public imagination. ...
A new paper ... aims to change that. ... introduces the first mathematically precise framework for what it would mean for one universe to simulate another — and shows that several longstanding claims about simulations break down once the concept is defined rigorously. His results point to a far stranger landscape than previous arguments suggest, including the possibility that a universe capable of simulating another could itself be perfectly reproduced inside that very simulation. ..."
From the abstract:
"The simulation hypothesis has recently excited renewed interest in the physics and philosophy communities. However, the hypothesis specifically concerns computers that simulate physical universes. So to formally investigate the hypothesis, we need to understand it in terms of computer science (CS) theory.
In addition we need a formal way to couple CS theory with physics. Here I couple those fields by using the physical Church–Turing thesis. This allow me to exploit Kleene’s second recursion, to prove that not only is it possible for us to be a simulation being run on a computer, but that we might be in a simulation that is being run on a computer – by us.
In such a ‘self-simulation’, there would be two identical instances of us, both equally ‘real’. I then use Rice’s theorem to derive impossibility results concerning simulation and self-simulation; derive implications for (self-)simulation if we are being simulated in a program using fully homomorphic encryption; and briefly investigate the graphical structure of universes simulating other universes which contain computers running their own simulations.
I end by describing some of the possible avenues for future research. While motivated in terms of the simulation hypothesis, the results in this paper are direct consequences of the Church–Turing thesis. So they apply far more broadly than the simulation hypothesis."
I end by describing some of the possible avenues for future research. While motivated in terms of the simulation hypothesis, the results in this paper are direct consequences of the Church–Turing thesis. So they apply far more broadly than the simulation hypothesis."
