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Existing back in time where the general temperature of space was 0 celsius? (kbin.social)

submitted 1 year ago by [email protected] to c/[email protected]

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If we copied/moved our planet and us as we are now back in time that far away, what would happen?

Could we survive, or are we bombarded to death by something, or something else?

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[–] StarManta 0 points 1 year ago* (last edited 1 year ago) (1 children)

Well, are we also copying the sun? If not, this is a very easy question - we’d freeze to death quite quickly.

If we do copy the sun and moon along with us, we might have a little bit of environmental trouble, but not by much. There isn’t much difference between 2.7K and 0K, and I don’t think we would feel all 2.7 degrees of difference on account of greenhouse effect. Even if we did, we are pretty good at warming up our planet; if we found ourself in this scenario we could globally give up on whatever efforts to curb climate change we’re doing now, and we could counteract 2.7 degrees of difference within several decades, and then we’re back to where we started.

[–] [email protected] 2 points 1 year ago

Please note that 0K is not the same as 0C.
I am asking about the time where the average temperature of space everywhere was 0 celsius, NOT Kelvin.

[–] [email protected] 0 points 1 year ago (1 children)

Space is currently at approximately NEGATIVE 270 Celsius. The last time that the general temperature of the universe was zero Celsius it was probably some short (cosmologically speaking) time after the Big Bang and consisted of some sort of hypothetical gluon/plasma/quark/condensate. All matter as humans understand it is gone in a practical instant.

[–] [email protected] 2 points 1 year ago* (last edited 1 year ago) (1 children)

Are you trying to say that all matter was in its building block shape when the general temperature was 0 celsius?
And when that material touches us, we'd become same stuff and stopped existing as we are now (evaporate).

[–] [email protected] 1 points 1 year ago* (last edited 1 year ago) (1 children)

Don't take my opinions too seriously, I'm just referencing my Astronomy notes (of which come from a single semester of a single class). With that said, here's my 2¢ guess:

I think they're trying to say that the last time the universe as a whole was 0°C, was probably before the formation of matter in the universe (I'll guess the inflation era, just after the birth of the universe, somewhere 10^(-35 to -33) seconds).

At this point in the universe, atoms cannot form (as the nuclear forces binding atoms are overwhelmed by the gravitational forces of all the energy in the Universe — you ever crush a cracker? It'd probably be like that). Perhaps even sub-atomic particles (protons, neutrons, etc.) can't form. All that's there is sub-sub-atomic particles (which we don't know much about, from my understanding).

So basically we (and the world, etc.) would be ripped apart at the sub-sub-atomic level by the immense forces (gravitational, etc. — remember, all of the matter/energy in the universe is being concentrated in a small place) of the early universe.

So, it's not that we would necessarily evaporate, nor that touching sub-sub-atomic matter would kill us, but more-so that we'd be crushed, at the sub-sub-atomic level, by the gravitational forces of the early universe. It'd probably be painless though, at least.

[–] [email protected] 1 points 1 year ago

Cool!

[–] [email protected] -1 points 1 year ago (1 children)

Space wasn't 0 Kelvin (I'm assuming you mean "absolute zero" because outer space is currently colder than 0°C/32°F) at any point in the past. In fact, the farther you go back in time, the warmer the universe gets, on average. This is because the same amount of energy was packed closer together when the universe was smaller. As the universe got bigger and things moved farther apart, the average temperature got colder.

As for what would happen if we magically teleported ourselves back to when the universe was very young, we would be cooked from all the radiation that was flying around, or if we went really far back, we'd just be blown apart because the entire universe was a hot plasma.

[–] [email protected] 2 points 1 year ago* (last edited 1 year ago)

Space wasn’t 0 Kelvin

I think you also misread my question/thread title 😁

In fact, the farther you go back in time, the warmer the universe gets, on average.

I know this. Space was Planck temperature in the first very short time when it was born. After that it started cooling down.
I tried to go back in history with my question.
.

As for what would happen if we magically teleported ourselves back to when the universe was very young, we would be cooked from all the radiation that was flying around

Okay, so at the general space temperature of 0 celsius the radiation was still too crazy for us to survive?

[–] [email protected] -1 points 1 year ago* (last edited 1 year ago) (1 children)

0 Celsius? Space is far colder than that. Did you mean 0 Kelvin?

We would all be very dead very fast. At 0 Kelvin the fundamental atomic particles have no motion. The heat of the earth primarily comes from our sun, and without that the geothermal heat would not be nearly enough to keep us warm and alive before the magma under the crust itself cooled off.

In ELI5 terms - space is colder than ice or even snow. It’s so cold that it would even freeze lava! Without our sun, the earth would get so cold that everyone and everything on it would turn to ice.

[–] [email protected] 2 points 1 year ago* (last edited 1 year ago)

I meant 0 celsius.
So we'd need to go THAT FAR back to history in our "mind game" where the most space in, well, "empty space", was 0 celsius.