What are the implications of an infinite large universe?

[SelfSim]

And .. to be fair, here's more of a philosophical one from a scientific/logical viewpoint which includes some views from scientists: Martin Rees, Anthony Aguirre, Raphael Bousso and Sean Carroll .. (oh yeah and the token philosopher: Joshua Knobe). Length is a quick 26 mins.
Also touches on what's been discussed:

 

[durangodawood]

We need the concept of time .. otherwise nothing makes sense. Our brains need the concept of time, in order for us to function as we do.

The idea that time is a 'thing' which floats around someplace which we then grab and attach it to our models of the universe ... is a pure belief that our minds bring into existence.

With this, the concept of time only happens because of us.
It wouldn't happen without us.

Maybe. Or time could be a feature of the universe. Despite your conclusion, the rest of your post leaves that possibility open.

 

[sjastro]

Let me put my two cents worth in.
On the subject of universes they are grouped into physical universes and mathematical universes.
The Big Bang and Steady State models are examples of physical universes.

The mathematics used in these models is used to describe something ‘real’ hence the term physical universe.
A mathematical universe on the other hand is a universe created by mathematicians with little regard to physical reality or based on ideas so obtuse it is impossible to visualize.
One such model is the Godel universe which is an infinitely large universe and rotates.
While this is mathematically possible, from a physical sense what is an infinitely large universe rotating relative to?
Trying to explain mathematical universes in a physical sense can lead to straightjackets and padded cells.
Kurt Godel of Incompleteness Theorem fame in fact starved himself to death and on his death bed queried astronomers if his infinite universe was found to be rotating.

The dividing line between physical and mathematical universes can be blurred.
Another example of a mathematical universe is a De Sitter universe.
With the development of quantum field theory and the discovery of vacuum energy the De Sitter universe now looks more like a physical universe.

Cosmologists believe in the very early history after the Big Bang our universe was in fact a mathematical De Sitter universe which developed into our current physical universe and will eventually revert back to a De Sitter universe in the very distant future.

 

[SelfSim]

Maybe. Or time could be a feature of the universe.

See, the thing is, that its easy to produce objective evidence that its us humans who come up with what 'universe' there, actually means. Its humans (like Einstein) who incorporate(d) time into the concept of a universe having the property of 'spacetime', (as an objectively demonstrable justifiable example leading to that conclusion).
There is no objective test which excludes the influence of our minds, which would permit us to conclude that time exists (objectively) independently from us.
My point is, therefore, actually a conclusion formed on objective evidence (with none for the other).

Despite your conclusion, the rest of your post leaves that possibility open.

.. a 'possibility' there, which has no objective test(ability) .. or, in other words: a belief!

 

[dlamberth]

See, the thing is, that its easy to produce objective evidence that its us humans who come up with what 'universe' there, actually means. Its humans (like Einstein) who incorporate(d) time into the concept of a universe having the property of 'spacetime', (as an objectively demonstrable justifiable example leading to that conclusion).
There is no objective test which excludes the influence of our minds, which would permit us to conclude that time exists (objectively) independently from us.
My point is, therefore, actually a conclusion formed on objective evidence (with none for the other).
.. a 'possibility' there, which has no objective test(ability) .. or, in other words: a belief!

It's great mental exercise though. It stretches the mind to reach out to the infinite.

 

[SelfSim]

It's great mental exercise though. It stretches the mind to reach out to the infinite.

The problem with unconstrained thinking is that there are too many possibilities to consider.

I guess that means that our minds are not so big that they don't fit into our concept(s) of the universe.

 

[durangodawood]

See, the thing is, that its easy to produce objective evidence that its us humans who come up with what 'universe' there, actually means.....

What objective evidence thats unconditioned by our minds? Are you sure you havent simply built another mind-dependent model there?

 

[Bradskii]

There is no objective test which excludes the influence of our minds, which would permit us to conclude that time exists (objectively) independently from us.

Time is the rate of change in any process. It needs no further definition. We don't need to define a second or a year. Ipso facto, if there is change, then time exists. Just like if there is a material world then gravity exists. No minds required.

 

[SelfSim]

What objective evidence thats unconditioned by our minds? Are you sure you havent simply built another mind-dependent model there?

All my models are mind dependent .. so are yours.

 

[durangodawood]

All my models are mind dependent .. so are yours.

Ok. Then how can you call the evidence for this one objective, but not the evidence for the others?

 

[SelfSim]

Time is the rate of change in any process. It needs no further definition. We don't need to define a second or a year. Ipso facto, if there is change, then time exists. ... No minds required.

Ok .. so how would you propose perceiving a change then?

 

[SelfSim]

Ok. Then how can you call this one objective, but not the others?

An objective model is one that's testable via the scientific method. One that's not, can be operationally defined as a belief.

 

[Bradskii]

Ok .. so how would you propose perceiving a change then?

I don't. But not perceiving change doesn't mean that change isn't ocurring. And if it is, then time exists.

 

[SelfSim]

I don't. But not perceiving change doesn't mean that change isn't ocurring.

.. 'change occurring' there would then be a belief! .. Now where did that come from?

And if it is, then time exists.

There's no need for the 'if' assumptions there .. they have no impact on any objective test capable of concluding that your model of 'change occurring' (and therefore: 'time exists') ... is just a belief!

The scientific method does not mention Step#X: 'Start with this assumption ..', (or in other words: 'If ... then ... else').

 

[renniks]

If the universe is infinite then anything possible is actual. I have two comments:

1. That must be right.
2. That cannot be right.

Pick a number...

The only thing infinite is God.

 

[Bradskii]

.. 'change occurring' there would then be a belief! .. Now where did that come from?
There's no need for the 'if' assumptions there .. they have no impact on any objective test capable of concluding that your model of 'change occurring' (and therefore: 'time exists') ... is just a belief!

The scientific method does not mention Step#X: 'Start with this assumption ..', (or in other words: 'If ... then ... else').

There was no-one around when the sun formed. When the solar system was created. When the earth cooled. Etcetera etc. But change was occuring. That's not a belief. So if change was ocurring, time existed. By definition.

 

[SelfSim]

There was no-one around when the sun formed. When the solar system was created. When the earth cooled. Etcetera etc. But change was occuring. That's not a belief. So if change was ocurring, time existed. By definition.

No .. everything you mention there, is one of science's operational models, (or theory), that was developed by scientific thinkers. It has been tested and even before it was tested, it was still conceived and expressed as a testable hypothesis.

The notion that those objects were around before we were, is basically a thought experiment, which also tests out as being consistent with the model which incorporates time as a dimension of space .. so as to make sense (among us) of our meaning of 'the universe'.

None of it is independent of human thinking minds.

 

[Bradskii]

The only thing infinite is God.

If God is eternal then He exists outside of time. If He is infinite, He exists within time. Lets go Option 2.

If He has existed for an infinite amount of time then time itself has, obviously, existed for an infinite amount of time.
Time measures change. It's the definition of time. If nothing existed then time would not exist.
So something has been changing for an infinite amount of time.
So something has always existed.

I'm quite happy with that. But are you?

 

[Bradskii]

No .. everything you mention there, is one of science's operational models, (or theory), that was developed by scientific thinkers. It has been tested and even before it was tested, it was still conceived and expressed as a testable hypothesis.

The notion that those objects were around before we were, is basically a thought experiment, which also tests out as being consistent with the model which incorporates time as a dimension of space .. so as to make sense (among us) of our meaning of 'the universe'.

These aren't models. They are physical facts.

Let's say the sun goes super nova. So it undergoes change. So we can see it happening in time. Time therefore exists. Then the exploding sun destroys the earth.

According to you, time then does not exist.

 

[SelfSim]

If God is eternal then He exists outside of time. If He is infinite, He exists within time. Lets go Option 2.

If He has existed for an infinite amount of time then time itself has, obviously, existed for an infinite amount of time.
Time measures change. It's the definition of time. If nothing existed then time would not exist.
So something has been changing for an infinite amount of time.
So something has always existed.

I'm quite happy with that. But are you?

Easier just to tell it like it objectively is, ie: Its @renniks's belief .. (and nothing more than one).