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(Big Think)   How small was the Universe when the hot Big Bang began?   (bigthink.com) divider line
    More: Cool, Big Bang, Universe, Cosmic microwave background radiation, General relativity, Physical cosmology, Dark matter, observable Universe, hot Big Bang  
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1581 clicks; posted to STEM » on 24 Dec 2021 at 1:05 PM (21 weeks ago)   |   Favorite    |   share:  Share on Twitter share via Email Share on Facebook



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2021-12-24 11:12:49 AM  
Universal grower
 
2021-12-24 11:28:29 AM  
It was the size of the universe.
 
2021-12-24 11:37:43 AM  
The universe had no idea how large it was, and that's probably why it went "bang".
 
2021-12-24 11:40:41 AM  
IIRC, Subby's mom drank two full bottles of Boone's Hill Farms finest before it all went down.
 
2021-12-24 11:41:40 AM  
 
jbc [TotalFark]
2021-12-24 12:55:23 PM  
It was in the pool.
 
2021-12-24 1:22:19 PM  
12 parsecs
 
2021-12-24 1:27:31 PM  

Marcus Aurelius: Repeating universe theory.


Yeah, yeah.  We've heard it all before.
 
2021-12-24 1:34:24 PM  

Angry Drunk Bureaucrat: It was the size of the universe.


That's no universe, that's you mom
 
2021-12-24 1:34:36 PM  
Bigger than a breadbox?
 
2021-12-24 1:35:17 PM  
/Schrödinger's 'r'
 
2021-12-24 1:40:21 PM  
Well duh, when you're dealing with actual stuff an infinitely small point is only an intellectual concept.

The tightest you can pack all the stuff into one spot is always going to be a specific non-zero number based on how much stuff you're cramming together, and how strong the forces doing the cramming are.
 
2021-12-24 1:46:53 PM  
Interesting article. Any astrophysicist out there want to weigh in on the evidence we're not seeing for an infinitely-dense and hot point-source? Is there any evidence for the expansion energy TFA says existed pre-big bang, or does it just make the math work out?

Is our directional perception of time a function of the expansion of the universe?
 
2021-12-24 1:50:11 PM  

Boudyro: Well duh, when you're dealing with actual stuff an infinitely small point is only an intellectual concept.

The tightest you can pack all the stuff into one spot is always going to be a specific non-zero number based on how much stuff you're cramming together, and how strong the forces doing the cramming are.


Even assuming TFA is correct about "expansion energy" decaying spontaneously into matter and radiation, there's a measurable limit to how densely energy can be condensed according to our best current theories.
 
2021-12-24 1:50:31 PM  
I'm personally a believer that our universe is inside a black hole in a larger, more diffuse universe. One that has different laws of physics. And each black hole in our universe is another smaller universe with different laws if physics.
 
2021-12-24 1:52:48 PM  
Never mind that the fart filled the room. How big was Gods arse?
 
2021-12-24 1:54:49 PM  
No point.  It was infinite, then expanded and cooled.

Now, you can say the observable universe was a small finite volume.  But you need that qualifier.
 
2021-12-24 2:03:13 PM  
A long time ago- Actually, never, and also now, nothing is nowhere. When? Never. Makes sense, right? Like I said, it didn't happen. Nothing was never anywhere. That's why it's been everywhere. It's been so everywhere, you don't need a where. You don't even need a when. That's how "every" it gets.
 
2021-12-24 2:05:38 PM  

Wenchmaster: Interesting article. Any astrophysicist out there want to weigh in on the evidence we're not seeing for an infinitely-dense and hot point-source? Is there any evidence for the expansion energy TFA says existed pre-big bang, or does it just make the math work out?

Is our directional perception of time a function of the expansion of the universe?


Quantum time and thermodynamic time are two separate things, AFAIK.  Going forward or backward in quantum time is possible.  Going backward in thermodynamic time is not.  Heat loss is a biatch.
 
2021-12-24 2:13:37 PM  
Forget this. I wanna be something. Go somewhere. Do something. I want things to change. I want to invent time and space, and I know it's possible because everything is here, and it probably already happened. I just don't know when to start.

/ And that's exactly where it started
 
2021-12-24 2:27:40 PM  
I have always wondered about what proved the "big bang" was singular, not a fractal cluster bomb.
 
2021-12-24 2:27:52 PM  
It was the size of the Schwarzchild radius of a Black Hole approximately the mass of Jupiter, maybe a little less.

Knowing this, some physics rules of the previous universe could be estimated.
 
2021-12-24 2:39:46 PM  

wax_on: I'm personally a believer that our universe is inside a black hole in a larger, more diffuse universe. One that has different laws of physics. And each black hole in our universe is another smaller universe with different laws if physics.


Why would the physics be different in each black hole universe?  Wouldn't each one be constructed of matter and physics of the parent universe?
 
2021-12-24 2:56:17 PM  
Subhead: "...we can see for 46.1 billion light-years in all directions..."

Article: "...the most ancient light we can see was emitted a whopping 13.8 billion years ago: corresponding to the hot Big Bang itself. Today, after traveling through our expanding Universe, that light finally arrives here on Earth, carrying information about objects that are presently located some 46.1 billion light-years away."

So, we cannot see 46.1 billion light years in all directions. It will be 32.3 billion years before that light reaches us.
 
2021-12-24 2:57:10 PM  

HawkEyes: wax_on: I'm personally a believer that our universe is inside a black hole in a larger, more diffuse universe. One that has different laws of physics. And each black hole in our universe is another smaller universe with different laws if physics.

Why would the physics be different in each black hole universe? Wouldn't each one be constructed of matter and physics of the parent universe?


Why would they be exactly the same?

But, if there was even the slightest difference when new universes were made, then the physics laws would evolve to favour those that create black holes. Which is what we observe.

Once the laws in any universe are optimal for black hole creation and seeding those laws to child universes, then the majority of universes would have similar physics laws and universes that deviated from that would not 'breed' as much.

After some number of generations of universes, deviation from the norm would be minimal, but it may still exist.

In the same way, you are slightly different from your mom, and me, but not so different that you are unrecognizable as human.
 
2021-12-24 2:58:21 PM  
I have no idea. Let's ask your mom
 
2021-12-24 3:11:43 PM  

a particular individual: Subhead: "...we can see for 46.1 billion light-years in all directions..."

Article: "...the most ancient light we can see was emitted a whopping 13.8 billion years ago: corresponding to the hot Big Bang itself. Today, after travelling through our expanding Universe, that light finally arrives here on Earth, carrying information about objects that are presently located some 46.1 billion light-years away."

So, we cannot see 46.1 billion light years in all directions. It will be 32.3 billion years before that light reaches us.


Yeah, we can't see that far, and we never will. What they mean is that the furthest stars we can currently see that were 13.8 Billion light years away when their light was emitted, are currently 46.1 Billion light years away because space expanded in the 13.8 Billion years it took the light to get here. But in 46.1 billion years, space will have expanded a great deal more so the light they are emitting now, we will never see. That light will never reach us. They are currently moving away from us at about 6.5 light years per year...

Over time, the limit of our vision will reduce as distant objects move away from us, eventually leaving us only able to see our own galaxy, possibly some gravitationally bound objects.
 
2021-12-24 3:12:37 PM  

Bovine Diarrhea Virus: I have no idea. Let's ask your mom


You were 1 minute too late with your 'your mom' joke.
 
2021-12-24 3:16:22 PM  
Barely Legal Universes Getting Banged For The First Time!

Hot Lepton Action!

Quark Bukkake!

XXX-ray Activity!
 
2021-12-24 3:25:11 PM  

a particular individual: Subhead: "...we can see for 46.1 billion light-years in all directions..."

Article: "...the most ancient light we can see was emitted a whopping 13.8 billion years ago: corresponding to the hot Big Bang itself. Today, after traveling through our expanding Universe, that light finally arrives here on Earth, carrying information about objects that are presently located some 46.1 billion light-years away."

So, we cannot see 46.1 billion light years in all directions. It will be 32.3 billion years before that light reaches us.


The expansion of the universe since the light was emitted is the reason. Dark energy. Take a balloon before blowing it up. Put a bunch of dots right next to each other. Inflate the balloon. That balloon's skin is spacetime. The further away the points started at, the faster they move.

The universe has been expanding from before the first stars started burning. Light that began the journey early on has been pushed further away from the stars without actually having traveled the whole distance. Light speed only takes into account the distance traveled normally, not the expansion of spacetime itself. The further away two points are, the faster the recede. There are galaxies our telescopes can see today that will not be visible next year because at the largest scales the expansion is faster than light travels and is growing faster over time.

Also it affects shorter distances over time. Given enough time, if the rate of expansion of dark energy remain constant, globular clusters will be torn apart by dark energy, then galaxies, then even solar systems. At the end, dark energy would disrupt atoms and subatomic particles, finally reducing everything to the smallest quantum particles. That's the current conception of the heat death of the universe. But those particles aren't flying apart due to anything but there being more space between themselves, not because they have relative momentum.

Of course it could change at some point. But there are, to my knowledge, no theories to explain how it could change. So they just extrapolate the observations made today about the expansion rate over time (using various far-off galaxies as landmarks) and use those numbers. You can't currently measure it outside of studying light from various globular clusters at different relative distances. It's measured at the megaparsec scale.
 
2021-12-24 3:26:25 PM  
DNRTFA - but I'm guessing Planck length.
 
2021-12-24 3:33:42 PM  

Marcus Aurelius: Repeating universe theory.


I always thought that some form of a cyclic universe was the most philosophically acceptable outcome, more than 50 years ago. Of course, cosmology doesn't give a shiat what I think...nor does anybody else.
 
2021-12-24 3:36:41 PM  

HawkEyes: wax_on: I'm personally a believer that our universe is inside a black hole in a larger, more diffuse universe. One that has different laws of physics. And each black hole in our universe is another smaller universe with different laws if physics.

Why would the physics be different in each black hole universe?  Wouldn't each one be constructed of matter and physics of the parent universe?


One theory is the laws of every universe are tweaked slightly and so ours having the right preferences/ variables for life is just an accident with infinite multiverses and we just are naturally Here because this is the one that supports our form of life.

I kind of follow the universe as a black hole that expanded after it hit some sort of natural limit we don't understand. Space and time and magnetism and consciousness all compacted together into something that contained so much potential that expansion was inevitable in order for it to figure itself out once again.

Some kind of universal consciousness and cycle type of thing. Granted I've had an edible but this is all coming together nicely...
 
2021-12-24 3:37:42 PM  

Boudyro: The tightest you can pack all the stuff into one spot is always going to be a specific non-zero number based on how much stuff you're cramming together


Your mom begs to differ
 
2021-12-24 3:39:09 PM  
I hope the little boy don't fall and skin his knee...

THE GUESS WHO FEATURING BURTON CUMMINGS - Life in the Bloodstream (1971)
Youtube TB4e8EXb6ns
 
2021-12-24 3:58:05 PM  
Time to 'fess up, it was me! I did it!

Hawkwind - Master of the Universe
Youtube X3W7ch0oLeA
 
2021-12-24 4:02:19 PM  

Aquapope: Marcus Aurelius: Repeating universe theory.

Yeah, yeah.  We've heard it all before.


Yeah, yeah. We've heard it all before.
 
2021-12-24 4:04:26 PM  
Whoever made this graph:
Fark user imageView Full Size

Should feel bad.
 
2021-12-24 4:06:16 PM  

Unsung_Hero: No point.  It was infinite, then expanded and cooled.

Now, you can say the observable universe was a small finite volume.  But you need that qualifier.


If you're going to play with semantics, something that is infinite can not expand
 
2021-12-24 4:08:18 PM  

CivilizedTiger: Forget this. I wanna be something. Go somewhere. Do something. I want things to change. I want to invent time and space, and I know it's possible because everything is here, and it probably already happened. I just don't know when to start.

/ And that's exactly where it started


How many tabs did you eat?
 
2021-12-24 4:17:37 PM  
56 bytes

/we're in sim, sheeple.
 
2021-12-24 4:18:15 PM  

chitownmike: CivilizedTiger: Forget this. I wanna be something. Go somewhere. Do something. I want things to change. I want to invent time and space, and I know it's possible because everything is here, and it probably already happened. I just don't know when to start.

/ And that's exactly where it started

How many tabs did you eat?


history of the entire world, i guess
Youtube xuCn8ux2gbs
 
2021-12-24 4:27:40 PM  

chitownmike: Unsung_Hero: No point.  It was infinite, then expanded and cooled.

Now, you can say the observable universe was a small finite volume.  But you need that qualifier.

If you're going to play with semantics, something that is infinite can not expand


If you're going to try and understand physics... you're going to have to accept that it CAN.
 
2021-12-24 4:35:07 PM  

Mad-n-FL: I have always wondered about what proved the "big bang" was singular, not a fractal cluster bomb.


Fark user imageView Full Size
 
2021-12-24 4:38:19 PM  

HawkEyes: wax_on: I'm personally a believer that our universe is inside a black hole in a larger, more diffuse universe. One that has different laws of physics. And each black hole in our universe is another smaller universe with different laws if physics.

Why would the physics be different in each black hole universe?  Wouldn't each one be constructed of matter and physics of the parent universe?


Physics in all black holes are the same because it's the same black hole
 
2021-12-24 5:46:34 PM  

Unsung_Hero: No point.  It was infinite, then expanded and cooled.

Now, you can say the observable universe was a small finite volume.  But you need that qualifier.


Don't you need an observer for that?
 
2021-12-24 6:04:57 PM  

yakmans_dad: Unsung_Hero: No point.  It was infinite, then expanded and cooled.

Now, you can say the observable universe was a small finite volume.  But you need that qualifier.

Don't you need an observer for that?


Nope.  It's a theoretical limit on how far information can have propagated since the universe changed to a state where light could travel.
 
2021-12-24 6:32:46 PM  

dready zim: the furthest stars we can currently see that were 13.8 Billion light years away when their light was emitted, are currently 46.1 Billion light years away


I've been trying to wrap my head around the fact that "now" does not in any way apply to something that far away. The speed of light is the speed of causality. It's meaningless to speak of the shape of the universe "now."

There are parts of the universe that will never affect us; their existence will never have any effect on us because they exist outside our time. Infinite parts of the universe might as well be another universe, as far as we're concerned.
 
2021-12-24 6:39:34 PM  
The current theory is that the universe is and was always infinite (if I understand correctly, I'm not a cosmologist). The big bang did not happen in a dot but everywhere at once. I only scanned the article but it seems like it is talking about the observable universe.
 
2021-12-24 6:46:57 PM  

JRoo: Barely Legal Universes Getting Banged For The First Time!

Hot Lepton Action!

Quark Bukkake!

XXX-ray Activity!


These quarks go allllll the way down!
 
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