Infinite vs. Finite Universe

a reply to: Imhotepic

Actually, I may need to correct that. They (Cosmologists) have determined that the universe is flat, but finite or infinite is still debatable and to me actually sounds like it depends on what is meant by infinite.

As far as the Space is concerned it's Finite. But Time is infinite.

But it still depends on what is being meant by infinite because infinity is a weird thing to work with and is used differently.

originally posted by: Vortiki

Who is "they" and what "data" do "they" have that "proves" our universe is finite and flat?

As far is it being flat they got that by measuring it. I'll explain it in terms that I think I understand it. If you ask a cosmologist for the math and so forth I'm not sure what you'd get. But here it goes.

According to General Relativity Mass Curves Space. So the density of the universe spread over its volume determines its shape. If the Density is Less than Volume it's then the Mass isn't enough to stop the expansion and the Universe goes on forever. If it's more than the Volume it curves back in on itself. If it's the same then it's flat and will expand but will eventually stop expanding and balance out. Apparently our universe is balanced. Our Density matches our volume and should stop expanding at some point.

If it was more then we would be in a universe where it was a cycle of Big Bang to Big Crunch to Big Bang...repeat. If it was less then the space would just keep expanding until all mass would just keep getting further and further apart forever.

IMO, it's finite and this is why. First of all we have a limit on how small the smallest measurement of space can be which is Planck's Constant/Length. So until we discover a way to get smaller than that it's our finite limit getting smaller.

Also, our universe couldn't allow for Infinities to exist in some tangible way as anything that was infinite would then require all the space available and more. Our universe requires limits to things to make sense of them. However there are some things which are infinite but only in non-physical terms. This allows us to understand what infinity is to some degree and even play with it in math but it just doesn't seem to exist in physical ways.

To me this seems to mean that Infinity does in fact exist, just not here for us in any tangible way.

originally posted by: Imhotepic
a reply to: mOjOm

I disagree.

That's fine. Do you want to expand on why so we can discuss some ideas about it or are you just happy leaving it there??

Lol.. Finite? With what a wall? What behind the wall? Another universe? Then What is universe?

a reply to: mOjOm

I've seen the "flat" time-space model and it's wrong, it's only half of it. If you're are in fact refering to what I believe you are, often depicted as a ball sitting on a plane with a dip in the plane to represent the density of mass. However, that's only half of the picture, in three dimensional space, the pocket (dip representing density of mass) is around the entire planet, not just the planet sitting in a dip on a two dimensional plane.

I wish i could find a diagram to what I am trying to explain, these things are much easier explained with pictorial assistance lol


2d Space Time

That, is what you're used to seeing. However the top half of the diagram is missing, the bend is around the entire planet, not just a planet sitting on a 2d plane of space-time.

originally posted by: Imhotepic
To you, is the Universe infinite or finite? You can read academic papers on either side by simply searching google. I'm looking for more thoughtful, genuine responses than "Well this PhD says the universe is an infinite torus.". No.

In my opinion the Universe has to be infinite. How could you possibly reach a surface that was just the end of "the Universe"? Hypothetically, even if we assume that the Universe is finite and all of its volume is contained neatly within a sphere, what is surrounding the sphere that is our finite universe? Would electromagnetic waves cease to be transmitted through empty space outside of the known Universe volume in a finite universe scenario? Is nothingness a thing?

Ask Your self this. If Our universe is not finite. There was no singularity or begining of time.

If Our universe is infinite there was never a sigularity. And there was no beginning of time. It is this simple to understand.

a reply to: spy66

What about people who don't subscribe to the whole singularity thing?

originally posted by: Imhotepic
a reply to: spy66

What about people who don't subscribe to the whole singularity thing?

What about them?

How do they explain expansion when it comes to Our universe?

Dont expansion actually exist?

a reply to: spy66

How can an infinite volume expand? I think you are talking about the matter within the Universe dispersing from areas of higher concentration to areas of lower concentration.

originally posted by: Imhotepic
a reply to: spy66

How can an infinite volume expand? I think you are talking about the matter within the Universe dispersing from areas of higher concentration to areas of lower concentration.

Our universe is not infinite that is why it is can expand. That should prove that Our universe is finite and not infinite.

a reply to: spy66

How could you ever be so bold as the to claim that the Universe is finite and it's a fact? We can only see a small percentage of the surrounding Universe volume , just say we see 0.000000000078% of the entire universe. This would seem like a very small percentage when in fact this number is approaching positive infinity when it should be approaching zero. I think people fail to understand the vastness of the abyss. But It's ok, we can share differing opinions on the matter. You stick to your finite Universe and I'll continue to exist in my eternal, infinite sea.

originally posted by: Imhotepic
a reply to: spy66

How could you ever be so bold as the to claim that the Universe is finite and it's a fact? We can only see a small percentage of the surrounding Universe volume , just say we see 0.000000000078% of the entire universe. This would seem like a very small percentage when in fact this number is approaching positive infinity when it should be approaching zero. I think people fail to understand the vastness of the abyss. But It's ok, we can share differing opinions on the matter. You stick to your finite Universe and I'll continue to exist in my eternal, infinite sea.

Okay. No problem for me

a reply to: Imhotepic

Interesting question - I'll say this, when I was in secondary (high) school a good fifteen years ago (Wow that makes me feel old) I had a science teacher called Mister Williams, I asked him about the edge of the universe (keep in mind this was back in the late 90s early 00s) and said that I wanted to know what was at the end or edge of it and he said:

"You'd never get there. Even if the universe had an end or edge you'd never see it. You'd just keep travelling and travelling and even if you reach the point of the end/edge you'd pass it and just keep going without realising that you've passed it because if there is an edge the human mind, eye would have no idea how to recognise it"

Ever since then I've sort of been in the mid set that there is an edge to the universe but the way our mind and eyes see the universe wouldn't allow us to see it's end so we'd pass on by it and continue going. The best way I can describe the theory is this - I can't think of another way to put it if that doesn't make sense lol.

a reply to: Vortiki

It looks similar but no. That is talking about how mass bends space I believe. What I'm talking about is the net energy of our universe which is zero in theory. Meaning the matter in the universe balances out the gravity in our universe. This is what gives us a flat universe.

That's the theory anyway.

In my view, our universe (note that I said "our" and not "the") is a finite "bubble" expanding in an infinite and eternal multiverse.

As I see it, something infinite would also have to be eternal; infiniteness doesn't appear out of nowhere at some point in time.

So, we have an infinite and eternal multiverse, where "bubble universes", like ours, spontaneously appear due to false vacuum decaying to a lower energy state, as part of the eternal inflation.

The Universe is not infinite. We know little about space, Big Bang, Black Holes, Dark Matter, Multiverses that''s all things that make no sense.