When my brother was in a nursing suffering from several ailments including dementia he wandered off and fell down about three miles away.  A lady found him and called an ambulance which took him to the emergency room.  From there he was transported back to the nursing home.

When asked where he thought he was going he said he was looking for the edge of the universe so he could step off. 

It looks like he never would have found it.

https://www.popsci.com/science/is-the-universe-infinite/

Noel

The evidence we have suggests infinite. In reality though, we don't know. The universe appears flat but it might be so infinitesimally curved that we haven't got the capability to detect the curvature. 

I'm still fully convinced this is it and we sit on someone's fireplace mantel!

There was a recent article speculating on our Universe being inside a black hole in somebody else's universe, and that our own black holes might lead to additional universes, in a sort of infinite matryoshka-doll reality.

 

3 hours ago, charliearon said:

I'm still fully convinced this is it and we sit on someone's fireplace mantel!

I have often worried that our universe is the head of one of many matches in a box on someone's kitchen stove and wondering how far down the box we are.

Noel

It started with a bang and exploded outward forming the expanding in size dimensions of the universe. It's size is determined by the time. It will expand outward for a very long time and grow very large. It is possible for it to be infinite.

And possible that the Earth is flat and not a spheroid. But the probabilities for such too me seems very small. As is the probability that gravity is an illusion and I can safely jump off a cliff. But that might be true, it is quite possibly true. I don't think very probable.

Experiments, and the results of same, are the test to evaluate probabilities. Very few experiments can be done with lots of grandiose ideas in astrophysics. They create a scheme which remains untested. And as such, is just wild speculation.

Sorry can't help it, this topic made me think of this...

 

16 hours ago, Fielder said:

It started with a bang and exploded outward forming the expanding in size dimensions of the universe. It's size is determined by the time.

 

Not exactly. It wasn't an explosion and there was no "outward". And size is only relevant in terms of the observable universe. But we know there is more beyond. I think of the expanding universe as more of a reduction in temperature and density than a change in size. If Inflation is to be believed, and there is good evidence for it, then prior to the hot big bang, there was the inflaton field (inflation field) that field was expanding exponentially and when it stopped expanding energy was dumped into the field, particles created, jostled together and a hot big bang ensued. We have no idea if anything existed before the hot big bang (reheating) it may have just been an infinite and possibly eternal inflaton field, or perhaps some other entity, like a cosmological singularity.

What I find fascinating is that if we project forward in time until the universe has expanded that much that only a scalar field is left, it has the same characteristics as the Inflaton scalar field. So perhaps, if that stops expanding too.... and new big bang ensues. Cyclic universe. 🤔😮 Of course cats know but they wont bloody tells us. 🙄

The caveat to all of the above is that I haven't a clue what I'm talking about and only know about making muscles big. More accurately,  biggish. Kind off. 

Edited April 26, 20251 yr by martin-w

13 hours ago, Matthew Kane said:

Sorry can't help it, this topic made me think of this...

 

LOL!!!!  Back when SNL was funny.

The universe is big.  I don't know how big, but I know it's big.  Allow me to cite my source of this knowledge.

“Space is big. You just won't believe how vastly, hugely, mind-bogglingly big it is. I mean, you may think it's a long way down the road to the chemist's, but that's just peanuts to space.”

― Douglas Adams, The Hitchhiker’s Guide to the Galaxy

I have my own theory which some of you will no doubt refute.  That's fine because I really have this notion in my head with nothing to back it up.

I think it's a yo-yo effect.  The universe began with a singularity and the big bang.  The universe expanded for so many billions of years until we have what we have now.  But at some time the expansion will stop and the universe will start contracting until there is nothing left but the singularity waiting to start another big bang.  No telling how long this has been going on.

Just the musings of an old man who probably doesn't know what he's talking about.  I can hear Martin laughing out loud.

Noel

1 hour ago, birdguy said:

I think it's a yo-yo effect.  The universe began with a singularity and the big bang.  The universe expanded for so many billions of years until we have what we have now.  But at some time the expansion will stop and the universe will start contracting until there is nothing left but the singularity waiting to start another big bang.  No telling how long this has been going on.

 

That's known as the "big crunch" hypothesis, Noel. 

And here's a Crunchy.

 

5 minutes ago, martin-w said:

That's known as the "big crunch" hypothesis, Noel. 

And here's a Crunchy.

Or we might have the Big Rip, which is really scary, whether it affects me personally or not.

42 minutes ago, HiFlyer said:

the Big Rip

Never heard of that, I had to look it up.  My first thought was it sounds like it’s the Mother of all Farts. 😷

53 minutes ago, HiFlyer said:

Or we might have the Big Rip, which is really scary, whether it affects me personally or not.

 

I think the dreaded rip is less favoured, now.