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How to Understand the Universe When You’re Stuck Inside of It

quantamagazine.org

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Re: How to Understand the Universe When You’re Stuck Inside of It

#61

Post by Fellshard »

criloz2 wrote: post #37
asplake wrote: post #35

Earlier quoted context omitted.

Trying to make sense of that last sentence. Putting words in your mouth, but you mean that we live in a simulation, for some definition of 'simulation' that we don't yet fathom?

yeah, I think that simulation is the closest word that we have right now for describing it, like many other times a word tend to be overused to describe multiples related things, till a new word is invented

Projection? Seems most appropriate for what seems to be essentially an argument for a reified Plato's Cave.

Re: How to Understand the Universe When You’re Stuck Inside of It

#63

Post by criloz2 »

basq wrote: post #57
criloz2 wrote: post #34

Earlier quoted context omitted.

I will extend me a little and say that this is also important for AI, a good AI should be able to detect those "systems" and automatically transform then in wave functions example when we walk, we tend to transform our walk patterns to a wave function, till some unexpected change in the ambient appears, this frees our brain and allow us to think in another thing. try to walk with a pattern that does not tend to stabi…

What you've written is extremely interesting. Not sure how much of it I truly understand, but I wanted to add that your explanation for everything as a wave function reminded me of oscilloscope music, ie. depicting images with waveforms. A tutorial I watched demonstrates the drawing of a mushroom, then animates it by modulating with a larger wave. In my laymen's head model, Spacetime is like a very large wave that ev…

very interesting video, and yes the whole universe is modeled by a wave function, but we probably will never get access to it because of it necessary to observe the whole surface to get it, is like an atom trying to get a wave function of your body, it has not enough information for that.

but in reverse it works, you can get a wave function of the probabilistic states of your cell just observing your surface, if you are dead, they will be dead just a simple example

we can observe the whole surface of the sun and get an idea when it will die (because we have access to its wave function), also we can make valid conjectures about the probabilistic state of every atom and subparticle inside the sun.

Re: How to Understand the Universe When You’re Stuck Inside of It

#64

Post by danbruc »

inopinatus wrote: post #58
danbruc wrote: post #55

Earlier quoted context omitted.

I would raise the following objections. First, you place a lot of emphasize on perception. What if we kill - or lets say remove - all humans and animals and aliens from the universe so that we are only left with rocks and gas clouds and other stuff we would not usually link to perceiving the universe? Do you really think removing the last entity perceiving the universe would fundamentally change what is going on with…

> Or do you mean perceiving in a more general sense Yes. I'm using it to mean evaluation as the fundamental causal process. I don't believe consciousness is orthogonal to the universe, ergo it must emerge from the processes within it. Sorry, the term perception is a bit loaded in this regard. But here's the thing: I also don't want to exempt a complex emergent arrangement of functions from evaluating its neighbours.…

Do you mean the conclusion that the universe is a rigid block of spacetime?

Yes. You on the other hand try to place time outside of the universe and that means for me you are not talking about the entire universe. It is like talking about one frame of a movie, but one frame is of course not the entire movie. And while there is change from frame to frame the entire movie is static. Equally the universe in one moment is not the entire universe. Not to mention that the universe in one moment is - to put it mildly - a problematic idea as relativity teaches us that there are no such things as a universal time or universal simultaneity.

I used to accept that as an undergrad, eventually rejecting it for the most common reason of all: the denial of free will [...]

There are several different things that people may mean when they talk about free will but those fall into two categories. The first category contains variants of free will that do not require that the future is indeterminate, for example understanding free will as just doing what one prefers. The second category contains variants of free will that do require that the future is indeterminate but the problem is that those variants of free will are not logically consistent or not worth being labeled free will to begin with.

[...] justifying this to myself on the grounds it conflicts with the halting problem.

Would you mind elaborating this point?

[...] if the universe is functional [...]

What does this actually mean? What precisely distinguishes a functional from a non-functional universe?

[...] then its laws may evolve as it evaluates, including the laws by which it evaluates.

Give that I do not know what exactly you mean with a functional universe, this may go totally into the wrong direction, but at least naively I see no problem for the rules to simply change in any kind of universe. On closer inspection it is of course not that easy because it is pretty easy to end up with something inconsistent but those details aside, why would it be impossible for the gravitational law to become an inverse cube law tomorrow? Finally this raises all kind of new questions, for example just how many layers of laws describing change in the layer below are there? Is there a ultimate static layer that does not change? And over what time dimension do those laws change?

[...] the speed of light then emerges as a property of evaluative propagation through a functional universe [...]

Are you talking about the value of the speed of light or its existence? The value is arbitrary, the digits of c are of course just an artifact of the units we use. And even the value is inconsequential, i.e. whether c is c or 5c or 100c or 0.1c, you can just rescale it and call it one as physicists often do. The only thing that matters is whether the speed of light is finite or not.

Re: How to Understand the Universe When You’re Stuck Inside of It

#65

Post by inopinatus »

danbruc wrote: post #64
inopinatus wrote: post #58

Earlier quoted context omitted.

> Or do you mean perceiving in a more general sense Yes. I'm using it to mean evaluation as the fundamental causal process. I don't believe consciousness is orthogonal to the universe, ergo it must emerge from the processes within it. Sorry, the term perception is a bit loaded in this regard. But here's the thing: I also don't want to exempt a complex emergent arrangement of functions from evaluating its neighbours.…

Do you mean the conclusion that the universe is a rigid block of spacetime? Yes. You on the other hand try to place time outside of the universe and that means for me you are not talking about the entire universe. It is like talking about one frame of a movie, but one frame is of course not the entire movie. And while there is change from frame to frame the entire movie is static. Equally the universe in one moment i…

> Give that I do not know what exactly you mean with a functional universe, this may go totally into the wrong direction, but at least naively I see no problem for the rules to simply change in any kind of universe.

I'm sure that I don't know exactly what I mean, but I fully intend to find out.

A functional universe may be the only way to derive a Theory of Everything that is a) self-describing (and therefore recursively encodes all the "layers" simultaneously), and b) whose existence isn't rejected by the undecidability of the halting problem.

As to whether rules change; that might suggest that what we currently believe to be universal constants may not be constant, and that would be controversial besides.

> Would you mind elaborating this point?

I'm thinking directly of the arguments at https://en.wikipedia.org/wiki/Theory_of_everything#Arguments... (with the proviso that I believe Gödel's incompleteness theorem emerges as a corollary of Turing's proof of the undecidability of the halting problem).

> why would it be impossible for the gravitational law to become an inverse cube law tomorrow

Hard to rule out, isn't it? But in the circumstances I posit that we would not be around to perceive it. Hard not to consider one of the anthropic principles as a result. The proponents of the strong one might love the idea that a complex assembly of self-describing, self-evaluating functions is lazily evaluating the universe (but they'd be putting the cart before the horse)

> The only thing that matters is whether the speed of light is finite or not

To me the defining characteristic of c is that it is the fastest speed of propagation of evaluation, whether that is electromagnetic, or gravity waves, or any other of what we currently term the fundamental interactions. Agree, the term "speed of light" is misleading. But I went to school in a building named after James Clerk Maxwell and it's hard to give up.

Re: How to Understand the Universe When You’re Stuck Inside of It

#66

Post by avmich »

6thaccount2 wrote: post #49
avmich wrote: post #11

Earlier quoted context omitted.

Monads were used in APL language long before Haskell came to be. Surely all those are different monads though.

They are different...I can understand the APL ones. I have no idea what a "monoid in the category of endofunctors" means :)

Look at this statement enough times over long enough period, and it starts making sense.

"Category" is that central thing of the science of nodes and arrows between them.

"Functor" is a mapping - a function - from a category to another category, where each node is mapped and each arrow is mapped according to node mapping. Like, if 1 in number category maps to A in character category, 2 maps to B, and there is an arrow 1->2 in number category, then this arrow should map to arrow A->B in character category.

"Endofunctor" adds that the resulting category should in fact be the same as original. So, 1->2 can e.g. map to 3->4 in the same number category.

"Monoid" is requirement that with the category we also have defined binary operation (let's call it X), that the operation is associative and also that category has "identity" node (let's call it I) - that is, for any A both operations A X I and I X A both produce A. It's like adding with zero.

Now, this is not enough to understand monads - but it provides a foundation for what those monads, mathematically speaking, are. Consequences of these definitions can lead far :) .

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