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94% of the universe’s galaxies are permanently beyond our reach

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Re: 94% of the universe’s galaxies are permanently beyond our reach

#91

Post by otabdeveloper4 »

ASalazarMX wrote: post #89
otabdeveloper4 wrote: post #66

Earlier quoted context omitted.

If we're in a simulation then there aren't any alien civilizations. No sense wasting computational resources on them. P.S. As far as I know, computational complexity is the only physical quantity that doesn't obey conservation laws. So we're probably not in a simulation. If we were, it would probably be the other way around.

> If we're in a simulation then there aren't any alien civilizations. No sense wasting computational resources on them. Seeing how mindbogglingly huge the universe is, our insignificant planet is unlikely to be the most intensive object to simulate. For a Universe simulator it would be peanuts, less than peanuts, peanut crumbs that fell behind the pantry where you can't clean them.

Think of it this way: it's trivially easy to randomly generate terrain for a video game world. The "size" of the in-game universe is just an arbitrary parameter.

Populating the world with interesting NPCs, is, however, a vastly more difficult problem than just scaling the same copy-pasted planets and stars across light years.

So no, the size of our universe is just a scale parameter. There's no evidence that it's more computationally complex out there than here, and computational complexity is the only interesting metric.

Re: 94% of the universe’s galaxies are permanently beyond our reach

#92

Post by otabdeveloper4 »

techdragon wrote: post #79
otabdeveloper4 wrote: post #66

Earlier quoted context omitted.

If we're in a simulation then there aren't any alien civilizations. No sense wasting computational resources on them. P.S. As far as I know, computational complexity is the only physical quantity that doesn't obey conservation laws. So we're probably not in a simulation. If we were, it would probably be the other way around.

If we are in a simulation it’s most likely a physics/first-principles driven simulation… probably a “what if physics worked like $X” type of deal. So fidelity is likely the primary design goal and the weird nature of computational complexity in our universe is likely just an emergent property of the physics they setup the simulation with.

We seem to be living in some sort of an information complexity singularity, and it seems to be getting more complex exponentially with time.

No, I don't think this is some sort of accidental emergent property. Likely the information complexity singularity is the whole point.

Re: 94% of the universe’s galaxies are permanently beyond our reach

#93

Post by techdragon »

otabdeveloper4 wrote: post #92
techdragon wrote: post #79

Earlier quoted context omitted.

If we are in a simulation it’s most likely a physics/first-principles driven simulation… probably a “what if physics worked like $X” type of deal. So fidelity is likely the primary design goal and the weird nature of computational complexity in our universe is likely just an emergent property of the physics they setup the simulation with.

We seem to be living in some sort of an information complexity singularity, and it seems to be getting more complex exponentially with time. No, I don't think this is some sort of accidental emergent property. Likely the information complexity singularity is the whole point.

Not sure I agree about the overall information complexity, since a first principles physics simulation of a universe involves simulation of all the wave/quanta up through molecular dynamics and on to macroscopic behaviour of the universe (and us in it)…

It’s hard for me to imagine the “information complexity” we’re inducing into the universe as significant compared to the total size of the state machine representing all the neutrinos and photons in the universe, let alone the other particles.

Also if the the universe is a simulation it makes sense the simulators would be working with snapshots since even if you have the computational capabilities to simulate an entire universe, you probably don’t want to waste whatever time/energy resources exist in the simulating universe, simulating the first few billion years till your simulated universe gets to the point you’re most interested in, be it changing parameters / picking the outcome of particular random outcome or just zooming in and studying what goes on in the randomness, or just looking at it like some kind of highly advanced virtual zen garden.

So I’m not entirely convinced that our electronic computation devices which operate by way of the movement of electrons or photonics devices operating by manipulating photons (and usually electrons too), represents our hypothetical simulators having to design or run a simulation of anything beyond what we call “normal operating behaviour of clumps of solid baryonic matter”. All the computers in the world, full of electrons and interconnected by fibre optic lasers, is unlikely to involve simulating more electrons, neutrinos, and other subatomic particle interactions than are necessary to simulate the earth’s inner and outer core and their electrodynamic (which are coupled to the solar electrodynamics) and thus simulate the production of the earths magnetic field.

Re: 94% of the universe’s galaxies are permanently beyond our reach

#94

Post by davidhbolton »

rsj_hn wrote: post #4
Old_Paris wrote: post #2

This gives me existential dread

6% of galaxies ought to be enough for anybody. :)

Watching this simulated fly through of 400,000 actual galaxies blows my mind. Space is frickin huge... https://www.youtube.com/watch?v=08LBltePDZw&t=31s

Re: 94% of the universe’s galaxies are permanently beyond our reach

#95

Post by ASalazarMX »

otabdeveloper4 wrote: post #91
ASalazarMX wrote: post #89

Earlier quoted context omitted.

> If we're in a simulation then there aren't any alien civilizations. No sense wasting computational resources on them. Seeing how mindbogglingly huge the universe is, our insignificant planet is unlikely to be the most intensive object to simulate. For a Universe simulator it would be peanuts, less than peanuts, peanut crumbs that fell behind the pantry where you can't clean them.

Think of it this way: it's trivially easy to randomly generate terrain for a video game world. The "size" of the in-game universe is just an arbitrary parameter. Populating the world with interesting NPCs, is, however, a vastly more difficult problem than just scaling the same copy-pasted planets and stars across light years. So no, the size of our universe is just a scale parameter. There's no evidence that it's mor…

This assumes humans are interesting NPCs. I feel like we're the bizarre comic relief planet for the really interesting players to have the space adventure of the day.

I understand your point, though, but even if it was true, keeping track of all the physics in the Universe's filler would demand more processing power than what is needed for our planet. The speed of light would be our rendering depth, and that's still an unthinkable amount of computing, copy-paste included.

Re: 94% of the universe’s galaxies are permanently beyond our reach

#96

Post by metagame »

peterburkimsher wrote: post #51
metagame wrote: post #37

Earlier quoted context omitted.

This assumes that we're "truly" sentient, and on top of that, that we have actual free will. Both seem unlikely if things are actually simulated.

Thank you metagame for considering the philosophical and mathematical implications! Here's an (unpublished) proposal for a consistency proof that free will is finite. Conway's Free Will Theorem: "if we have free will ... so must some elementary particles" https://en.wikipedia.org/wiki/Free_will_theorem Infinity cannot be approximated with finite numbers (MIP* = RE "Prior to the new work, mathematicians had wondered w…

Do you have a blog, by chance? Your writing style's really engaging.

Re: 94% of the universe’s galaxies are permanently beyond our reach

#97

Post by peterburkimsher »

metagame wrote: post #96
peterburkimsher wrote: post #51

Earlier quoted context omitted.

Thank you metagame for considering the philosophical and mathematical implications! Here's an (unpublished) proposal for a consistency proof that free will is finite. Conway's Free Will Theorem: "if we have free will ... so must some elementary particles" https://en.wikipedia.org/wiki/Free_will_theorem Infinity cannot be approximated with finite numbers (MIP* = RE "Prior to the new work, mathematicians had wondered w…

Do you have a blog, by chance? Your writing style's really engaging.

Please email me! peterburk@gmail.com

It takes me a while to write blog posts, but I have some rough notes about many topics: fractals especially the Sierpiński triangle, singing/reading/writing/listening/speaking/typing, therapeutic games, language invoking spirits, aunties dancing in parks to keep streets safe at night (via HN).

If you'd be willing to read those rough notes and tell me which categories are more interesting, that would help to prioritise the blog post writing! Like a good engineer, it's turning vague user requests into specific actionable requirements.

Here's the briefest of thoughts about litter and saving the environment:

• Love your neighbours the trees and birds. People first, but we are to steward God's creation. The ocean knows us only by our litter.

• While you go, clean now. "If not me, who? If not now, when?"

UncleBob says this also applies to code:

https://www.youtube.com/watch?v=BSaAMQVq01E&t=2021s

• When people say "thank you", tell them to thank God, and welcome them to the community to do likewise. Give them a bag to clean with.

nanoLyrics is a rough tool that I've used recently for finding puns, analogies, and song lyrics.

https://peterburk.github.io/programs/nanoLyrics/nanoLyrics.h...

I look forward to hearing from you soon, metagame! We can talk about metaphysics, or even better, metageography.

Re: 94% of the universe’s galaxies are permanently beyond our reach

#98

Post by lostmsu »

garmaine wrote: post #83
milleramp wrote: post #43

Is there a galaxy on the boundary that is half disappeared (to us) and half visible?

No. The proper boundaries are between galaxy clusters, which remain gravitationally bound to each other. If you can reach a cluster such that its gravity is strong than the expansion of the universe, then you can reach every part of that cluster.

Does the mean, that the cluster, that is going to become unreachable next is going to "become" unreachable in its entirety in a single unit of time (like maybe Plank time)?

Re: 94% of the universe’s galaxies are permanently beyond our reach

#99

Post by lostmsu »

lostmsu wrote: post #98
garmaine wrote: post #83

Earlier quoted context omitted.

No. The proper boundaries are between galaxy clusters, which remain gravitationally bound to each other. If you can reach a cluster such that its gravity is strong than the expansion of the universe, then you can reach every part of that cluster.

Does the mean, that the cluster, that is going to become unreachable next is going to "become" unreachable in its entirety in a single unit of time (like maybe Plank time)?

To answer myself: yes. The clusters close to the outer event horizon are moving away from us at the speeds extremely close to the speed of light. Correspondingly from our standpoint of view their length along that direction is extremely contracted, and gets closer and closer to infinitesimally small as they get closer and closer to the horizon.

Re: 94% of the universe’s galaxies are permanently beyond our reach

#100

Post by lostmsu »

Gigachad wrote: post #61
ajnin wrote: post #18

It's mind blowing to imagine that the observable universe is bigger than 90 billion light years, space-time expanding at multiple times the speed of light. If expansion keeps accelerating, then at some point gravity won't be able to keep the local cluster together and even those galaxies will drift away, then star systems, then planets, then matter itself will be torn apart until atoms and particles and quarks are de…

I saw a video proposing that it might be possible that the universe collapses on itself again and everything is reset. But there are more non reversible things going on than just expansion. I only just found out that all elements radioactively decay and will eventually be gone.

That does not work like that in the presence of other forces. E.g. you can "undecay" plutonium by pressing together lighter atomic nuclei.
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