[enrmarc]

I do it every day, although my background in maths/physics is not enough to do it "the scientific way". There is one topic I'm constantly thinking about: "Where is the data, e.g. the mass of a planet, stored in our universe?".

I guess this question arise because of my computer science background (algorithms + data = universe?) and because even simple formulas like the Newton's Law of Universal Gravitation deals with data (e.g. the mass of a planet). So, where is that number stored so the universe know how to apply its formulas (laws, algorithms)? I know these laws we have are just models of our reality that are getting more precise over time, but I can't help but think that at the end our universe has to do "some calculations" and has to deal with data (numbers). I know three devices that can store information: our brains, our DNA, and our computers. The color of our eyes are stored in our DNA, but the mass of a planet is not stored anywhere?

As I've said, my limited maths/physics background doesn't let me think about the universe the right way. I'm just a dilettante. And sorry for my English.

[logfromblammo]

How would we know if we were in a real universe or a perfectly accurate simulation of one? If we were in a simulation, how would we know whether it modeled the same rules as the host universe, or an imagined fantasy universe?

If we are living in a nonfictional simulation, mass data are stored in a colossal server farm. If we are living in a fictional simulation, the mass data are stored in a thing we cannot possibly comprehend. If we are living in a real universe, mass data are not "stored" anywhere, in the same sense that consulting a map at 1:1 scale is indistinguishable from actually visiting the landscape it represents. Storing that data elsewhere is neither useful nor necessary.

[jtrip]

I ask, what is the qualitative difference?

[akvadrako]

I would say you have to start by defining "real". Surely a simulation is real in the sense that it takes up physical resources, has to be internally consistent and other such criteria. Importantly, abstractions within it can have experiences that are just as meaningful as those outside.

Maybe it's about being a "top-level" universe, which is self-defining and without physical constraints? It seems ours is unlikely that if inflation theory pans out, instead being just a self-contained world in the multiverse, not so different than any other simulation.

Personally, but without much evidence, I suspect there are no top-level universes; perhaps they do cycle around though, so very large scales eventually become the very small.

[logfromblammo]

For us? None.

We store reduced-precision, reduced-accuracy copies of the mass data wherever we keep the logs for our measurement devices. We can't get at the "real" numbers, anyway, so we just go by what our instruments say.

We can, however, "write" to the real data store for mass--by doing things like picking up rocks and throwing them. If we are living in a simulation, and it is imperfect, we could potentially exploit an imperfection by manipulating the simulation in just the right way.

[AnimalMuppet]

Seems to me that the data is stored in the positions of the particles that make up the planet.