this post was submitted on 19 Sep 2023
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science
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just science related topics. please contribute
note: clickbait sources/headlines aren't liked generally. I've posted crap sources and later deleted or edit to improve after complaints. whoops, sry
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At some point wouldn't gravity override the expansion and cause a contraction again?
Last I checked, the "Big Crunch" hypothesis got rejected by scientists.
I am no expert, so can't elaborate any further.
That's alright, I wasn't an expert when I asked the question. I was just curious about it.
I am an expert. But not on this topic so I can't help y'all.
The effects of gravity spread at the speed of light. If the sun suddenly blinked out of existence, it would take eight minutes to both see it disappear from Earth and notice a change in our planet's motion. In other words, the planet would continue to orbit that empty space in the middle because the sun's gravity, much like it's light, would still be extending out to us.
The universe is expanding in every part of space all at once. Some places are so far apart that the collective expansion between them is growing at greater distances in a given amount of time than light can travel. And the same can be said for the effects of gravity, but the motion of objects caused by gravity at great distances is far, far slower than the speed of light.
Our galaxy is moving in a direction that is caused partly by something called "The Great Attractor." But even though it's causing us to move, we will never reach it, and it's influence on us will gradually weaken. And it's not even that far away compared to most of what we know is out there.
That being said, this news is interesting.
No, the expansion is accelerating.
If it was gravity causing it, it wouldn't be unusual.
If the gravity is behaving as it is currently understood by the scientific community, it would indeed be unusual.
Heres a great source
It explains why the universe will have a cold death instead of a heat death.
Right now the universe is expanding and its expanding faster today than yesterday. Things could change, but current math points to a cold death
I always interpreted "heat death" as "the death of heat" instead of "a hot death"
Your interpretation is correct.
You are correct and I misremembered it. "The Big Freeze" and "Heat Death" are the same thing. Thats when everything expands until there is no more heat.
If someone knows the correct terms for what I am talking about please let me know. Let me explain further.
What I am talking about is the opposite of heat death, which is somehow in my mind at a hot death? Basically, where everything goes back to one singularity instead of expanding forever.
Big crunch is what I've heard it called but I don't know if that's what you're thinking of. Googling that might give you a start though.
That IS the heat death of the universe. It's not heat death as in "a wave of heat destroys everything" or anything like that, it's heat death as in "there is no more heat(aka condensed energy), everything is equally cold(aka lack of condensed energy) everywhere. Heat itself is gone, has died".
That is correct and I misremembered. For some reason a heat death makes me think of going back to a singularity because a singularity would probably be the hottest thing ever. Ironically, a heat death would be really cold