It's not, as Carl Sagan famously said, billions and billions - Politics Forum.org | PoFo

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#15235497
"Some 40 years ago, Carl Sagan taught the world that there were hundreds of billions of stars in the Milky Way alone, and perhaps as many as 100 billion galaxies within the observable Universe. Although he never said it in his famous television series, Cosmos, the phrase “billions and billions” has become synonymous with his name, and also with the number of stars we think of as being inherent to each galaxy, as well as the number of galaxies contained within the visible Universe.

Our most detailed observations of the distant Universe, from the Hubble eXtreme Deep Field, gave us an estimate of 170 billion galaxies. A theoretical calculation from a few years ago — the first to account for galaxies too small, faint, and distant to be seen — put the estimate far higher: at 2 trillion. But even that estimate is too low. There ought to be at least 6 trillion, and perhaps more like 20 trillion, galaxies, if we’re ever able to count them all."
https://bigthink.com/starts-with-a-bang ... ket-newtab

It's trillions and trillions now, try wrapping your head around that one.
#15235524
To quote a true visionary:
The Universe is a very big thing that contains a great number of planets and a great number of beings. It is Everything. What we live in. All around us. The lot. Not nothing. It is quite difficult to actually define what the Universe means, but fortunately the Guide doesn't worry about that and just gives us some useful information to live in it.

Area: The area of the Universe is infinite.

Imports: None. This is a by product of infinity; it is impossible to import things into something that has infinite volume because by definition there is no outside to import things from.

Exports: None, for similar reasons as imports.

Population: None. Although you might see people from time to time, they are most likely products of your imagination. Simple mathematics tells us that the population of the Universe must be zero. Why? Well given that the volume of the universe is infinite there must be an infinite number of worlds. But not all of them are populated; therefore only a finite number are. Any finite number divided by infinity is zero, therefore the average population of the Universe is zero, and so the total population must be zero.

Art: None. Because the function of art is to hold a mirror up to nature there can be no art because the Universe is infinite which means there simply isn't a mirror big enough.

Sex: None. Although in fact there is quite a lot, given the zero population of the Universe there can in fact be no beings to have sex, and therefore no sex happens in the Universe.”


Infinite
“The Hitch Hiker's Guide to the Galaxy offers this definition of the word "Infinite".

Infinite: Bigger than the biggest thing ever and then some.

Much bigger than that in fact, really amazingly immense, a totally stunning size, "wow, that's big", time. Infinity is just so big that by comparison, bigness itself looks really titchy.

Gigantic multiplied by colossal multiplied by staggeringly huge is the sort of concept we're trying to get across here.”
#15235621
ness31 wrote:
I think we all knew that didn’t we? It’s probably not even a quantifiable number. I’ve just always gone with infinite. It’s all infinite up there..



If you go back, our estimate of the size of the Universe goes up every time we build a better telescope.

We don't know if the Universe is infinite. I personally doubt it, but it does appear to be expanding. It's one of the things that suggests we need a better model of what the Universe is
#15235627
late wrote:If you go back, our estimate of the size of the Universe goes up every time we build a better telescope.

We don't know if the Universe is infinite. I personally doubt it, but it does appear to be expanding. It's one of the things that suggests we need a better model of what the Universe is


So the question is, what would cause the universe to cease its expansion? Otherwise, isn’t it infinite?

What model of the universe do we have currently?

Also, I can’t remember , but did we send something into a black hole?
#15235629
ness31 wrote:
So the question is, what would cause the universe to cease its expansion? Otherwise, isn’t it infinite?

What model of the universe do we have currently?

Also, I can’t remember , but did we send something into a black hole?



I don't know if it is infinite. Expansion doesn't have to imply infinite, it implies that it's likely to be finite. That it's headed towards infinity, like in calculus.

There's different models.

There are no nearby Black Holes that we know of. That would be very bad, should a rogue Black Hole enter our solar system.
#15235648
I don't know if it is infinite


Some things are just innate.

I don't know if it is infinite. Expansion doesn't have to imply infinite, it implies that it's likely to be finite. That it's headed towards infinity, like in calculus


I don’t understand. So the expansion implies a finite quality; but also maybe an infinity comparable to that in calculus, which still implies ‘no limits’.

There's different models.


I’m sure we can knock one up that accommodates all our paradoxes :lol:

There are no nearby Black Holes that we know of. That would be very bad, should a rogue Black Hole enter our solar system.


https://www.theguardian.com/science/202 ... nomers-say

This was the last one I’d heard about, you’re right, it’s not close. So we haven’t been able to send anything into a black hole …what a shame, who knows where it might lead .
#15235652
ness31 wrote:
Some things are just innate.



I don’t understand. So the expansion implies a finite quality; but also maybe an infinity comparable to that in calculus, which still implies ‘no limits’.



I’m sure we can knock one up that accommodates all our paradoxes :lol:



https://www.theguardian.com/science/202 ... nomers-say

This was the last one I’d heard about, you’re right, it’s not close. So we haven’t been able to send anything into a black hole …what a shame, who knows where it might lead.



Innate means belonging to the essential nature of something. But we just don't know what the 'essential nature' of the Universe is. It's what we are trying to find out.

Some equations can be headed towards infinity, but take infinitely long to get there. That's what I was trying to say. But it's just a guess on my part.

You can measure how long it would take for us to learn enough to play with Black Holes in thousands of years. Ask again in 10,000 years.
#15235655
Innate was kind of what I was referring to in my first post. When you were a kid, and you didn’t know much about much, but you knew that the sun came up in the morning and that tomorrow would be another day; didn’t you also just know that space was ‘infinite’? Because if it were not infinite, what else could it be?

But I look forward to hearing the best educated guesses out there :)
#15236902
I'm way above my pay grade here.


Oh, me too! Who cares?

Is an accelerating Universe compatible with a cyclic Big Bang theory? I don't know, but it doesn't look like it.


That’s what I thought you were getting at. Why couldn’t it be compatible? It has to be expanding, right up until it’s crunching :lol:

I’m assuming when we’re being crunched, life ends as we know it…because it doesn’t sound good.

It would be like God having his favourite song on repeat..or more like a gamer starting their current level again.
#15236910
ness31 wrote:


That’s what I thought you were getting at. Why couldn’t it be compatible? It has to be expanding, right up until it’s crunching




It's the inverse square law. Keep expanding and the matter in the Universe gets too far apart to ever pull itself back together. Or at least that's the thinking..

I suspect we are missing something.
#15236918
wat0n wrote:@Potemkin is probably the only user qualified enough to talk about this.


Really? I have no idea what Sir Potemkin does. I always thought he was in the ‘wordy’ business because he writes so nicely..
#15236922
wat0n wrote:He's a physics PhD

MPhil, in nuclear physics. My PhD is in film studies from Edinburgh University. My thesis was on Soviet montage cinema of the 1920s. Yeah, I switched horses halfway around the track. Lol.
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