Vulnerant omnes, ultima necat

As many physicists, I have always wondered how strange quantum physics was. One of the numerous things in this theory that make me scratch my head is how come time and space could be discrete instead of continuous. For those not familiar with quantum physics, the space being discrete means that there exists a minimal space lenght, or space « resolution », that cannot be further divided; same thing for a discrete time: it means there exists a minimal time lapse that cannot be further shortened, so that you would jump directly from time T1 to time T2 without passing through T1+t with 0 < t < T2-T1. But how strange it can seem, it is what we observe. Space, time and energy are all discrete. How is that possible?

I knew for some time that computers were beginning to become powerful enough to allow us to simulate the creation and the evolution of the Universe at some scale. The article Did our cosmos exist before the big bang? I read in the 10 December 2008 issue of the New Scientist was for me simply an update in this field. Then, one month later, I read Our world may be a giant hologram in the same magazine.

Being recalled about the Planck length and the time being discrete in the latter article in the context of a possible holographic principle, I wondered once again what could make time and space discrete. Then I thought: « It’s weird: it’s like if we were driven by a computer clock and meshed with a certain limited resolution… ». That was it. I thought about the December article on computer simulation of the Universe… What could prevent us in the future to create computers powerful enough to simulate the whole Universe with all its atoms forming planets, life and intelligent beings? And, correlatively, what would forbid us being such simulated intelligent beings? Could we be part of a gigantic computer simulation? Why not? If we were part of a computer simulation, how could we know it? Wouldn’t we observe exactly what we observe, that is, that both space and time exist in a limited « resolution »?

I wondered if other people could have already thought of that. Unsurprisingly, there were. Notably, I found the very well written ARE YOU LIVING IN A COMPUTER SIMULATION?. I don’t think though that there would be a need for « compressed distant objects » or that details would be added on a « as-needed basis »: if the whole universe and all its atoms are simulated as-is, everything will just look how it should, down to the maximum resolution allowed. Also, nothing tells us that any simulation would necessarily be a perfect reproduction of the world/simulation it comes from: tweaking the physicial constants in order to obtain different universes and possibly different viable outcomes is certainly something we can think of. BUT, nonetheless, the main idea behind this article seems hardly rebuttable:

« At least one of the following propositions is true: (1) the human species is very likely to go extinct before reaching a “posthuman” stage; (2) any posthuman civilization is extremely unlikely to run a significant number of simulations of their evolutionary history (or variations thereof); (3) we are almost certainly living in a computer simulation. It follows that the belief that there is a significant chance that we will one day become posthumans who run ancestor-simulations is false, unless we are currently living in a simulation. »

The following articles and pages are also very interesting:

• The Physicial World as a Virtual Reality
• A Cybernetic Interpretation of Quantum Mechanics
• The simulation theory | Quantum Philosophy
• Simulated reality – Wikipedia
• The VR Hypothesis