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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

#51

Post by peterburkimsher »

metagame wrote: post #37
gremlinsinc wrote: post #24

Earlier quoted context omitted.

If we're in a simulation...couldn't we learn to reprogram/hack the sim, and just put our spaceships in another galaxy?

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 Here's an (unpublished) proposal for a consistency proof that free will is finite.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 whether they could get away with approximating infinite-dimensional matrices by using large finite-dimensional ones instead. Now, because the Connes embedding conjecture is false, they know they can’t.")

https://www.quantamagazine.org/landmark-computer-science-pro...

-> Numbers cannot have infinite strings of digits

-> The future can never be perfectly preordained (Gisin "If numbers cannot have infinite strings of digits, then the future can never be perfectly preordained.")

https://www.quantamagazine.org/does-time-really-flow-new-clu...

Computers can only run recursive simulations, they can never actually reach infinity. The Turing Machine (cellular automaton Rule 110) can only expand to the limit of the tape.

Yet we can choose to surrender our free will to the greater good, and be part of the infinite pattern (cellular automaton Rule 90 Sierpinski Triangle). Rather than crystallising in ourselves, we should thank the root node, and thank others and love our neighbour, continuing the growth.

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

#52

Post by cbogie »

awb wrote: post #45
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…

> the careful balance of universal constants that allow for matter and stars and life to exist surely would not allow it all to be destroyed forever in the end... Imagine a brute-force creation of x^y universes with varying cosmological constants. Surely some universes with the right ingredients for life also include a deep freeze or a Big Crunch. Or, maybe our universe was created in a lab somewhere and they’re tryi…

42 would be the answer, huh. and in which case, were it to be true, we'd have a mighty strange prophetic bible on our hands.

on second thought, at least it was entitled to be a poor man's manual for gettin around these parts.

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

#53

Post by kamaal »

throwawaylinux wrote: post #46
gremlinsinc wrote: post #23

Earlier quoted context omitted.

If this fact makes you uneasy just know that (nearly) 100% of the galaxy's solar systems except the one we're currently in are (likely) unreachable within your lifetime. Though to be fair, I think the original title can't possibly know this, for instance if we live in a simulation, what's to say that some sort of algorithm (assuming we learn to meta-code our own existence) could put us in any galaxy we choose... Or w…

100% of this solar system's other planets and moons are (likely) unreachable by you within your lifetime.

Nearly 100% of the countries on this very earth are unreachable to most poor humans within their lifetime.

And for a sizeable chunk of humans even reaching the very neighbourhood of their country, geography involves putting their lives on risk on a near sure to sink boat only to be shot/sent/sunk back by border police.

Humans are horrible at working together for their own good.

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

#55

Post by brundolf »

awb wrote: post #17
Old_Paris wrote: post #2

This gives me existential dread

Just to add to it: If you decided to travel to the furthest galaxies you could reach, at some point even they will move beyond the reach of Earth as space expands. To colonize them means to exile yourself from Earth permanently. Traveling through an infinitely expanding universe is like traveling into a permanent headwind in every direction.

Weird question I just thought of: if space is always expanding, why aren't the objects around us, even their very atoms, getting slowly torn apart? Are the forces holding them together just constantly pulling them back together? Is it just a very small amount of expansion at a human scale? Does this affect very sensitive measurements of distance?

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

#57

Post by goatlover »

koonsolo wrote: post #56

"most of the universe's galaxies are already receding faster than the speed of light" Relativity theory: "It's impossible to go faster than the speed of light" WTF?

The expansion of space doesn’t fall under that limitation. Spacetime isn’t a particle or collection of particles. It’s the gravitational field.

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

#58

Post by zamadatix »

koonsolo wrote: post #56

"most of the universe's galaxies are already receding faster than the speed of light" Relativity theory: "It's impossible to go faster than the speed of light" WTF?

Expansion isn't objects in space moving farther apart through space it's the change in the geometry of space itself. A poor analogy might be a continuous zoom of a map map on your phone while something always moves less than a constant speed limit of pixels per second on the screen. It is easy to see this object can move around locations on the map but may not be able to reach most of the map if it is zooming in fast enough that far away portions !at get farther away faster than it can travel to them at the constant pixels per second.
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