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Scale of the Universe

(scaleofuniverse.com)
249 points Leftium | 1 comments | | HN request time: 0s | source
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ralegh ◴[] No.40084787[source]
For a second I thought we'd seen a lot of the universe, the HDF being 1/5th the radius away and on googling Earandel is 2/3rds the radius... of the known universe.

"According to the theory of cosmic inflation initially introduced by Alan Guth and D. Kazanas, if it is assumed that inflation began about 10−37 seconds after the Big Bang and that the pre-inflation size of the universe was approximately equal to the speed of light times its age, that would suggest that at present the entire universe's size is at least 1.5×1034 light-years—at least 3×10^23 times the radius of the observable universe."

So, if true, all those metrics of atoms, stars, planets in the known universe are multiplied by 10^23.

Even if intelligent life were rare enough to only appear once per knowable universe, there could be 10^23 different intelligent species - single planet to galaxy spanning empires - that would probably never meet another intelligent species (except those with the same ancestors).

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deepsun ◴[] No.40086574[source]
The problem is in words "at present". There's no some global timeline to say "present". The time in far away places just didn't happen yet.

UPDATE: minor consideration -- time can flow at different speeds (e.g. gravitational wells). That's probably doesn't matter to our discussion, but just another argument against "at present".

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rspoerri ◴[] No.40086977[source]
Just because you dont see it, doesnt mean it didnt happen. The light the sun emits will only be seen by us ~8min later, but it's still being emitted right now.
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1. petsfed ◴[] No.40088643[source]
Sort of.

The concept of simultaneity is mind-bending when you really dig into it [0]. The upshot is that the hard problem of synchronizing distributed systems is a problem of fundamental physics, rather than simply the capabilities of any given developer. Its always nice to know that the reason you haven't met some specification given to you by a non-technical user representative is because meeting that specification violates the known laws of physics.

0. https://en.wikipedia.org/wiki/Relativity_of_simultaneity