If the universe is infinitely old, how did Today ever get here?

[Cypress]

Yes. That gives us the exploding dot.
It doesn't give us its origin or what was there before it.

The Kentucky Derby begins at a starting gate and
even actually ends
at a wire about two minutes later.

We don't have a finish time for the Big Bang yet,
but knowing post time doesn't give us the entire history of the universe, does it?

We only know when the universe began to inflate and expand from an initially hot, dense initial low-entropy state 13.7 billion years ago.

We don't understand physics at Planck-density, so in principle the initial state at Planck-density could have existed longer than that.

I just don't think it could be infinitely old, since that supposition seems to be irrational, illogical, and mathematically non-sensical.

 

[NiftyNiblick]

We only know when the universe began to inflate and expand from an initially hot, dense initial low-entropy state 13.7 billion years ago.

We don't understand physics at Planck-density, so in principle the initial state at Planck-density could have existed longer than that.

I just don't think it could be infinitely old, since that supposition seems to be irrational, illogical, and mathematically non-sensical.

That defines time in a manner than I admittedly can't imagine.
I can only envision time as a continuum in which every moment has a before and after,
and that can only be infinite.

We also seem to define the "universe" differently.

To me it's the all-inclusive everything
and not just the currently expanding flux of matter and the space in which it resides.
That's why there can only be one universe by the definition that I apply.

To me, it's both time and space without boundary,
simply because I can't imagine a boundary with nothing outside of it.

This is conceptual, not mathematical.
Mathematics apply within the context that they're applied,
but concepts don't necessarily lend themselves to explanations.
We can imagine inexplicable concepts.
We can imagine more easily and more broadly than we can explain,
but finite isn't something that I can even imagine.....for an all-inclusive universe.

 

[Into the Night]

Prior to this thread, you never, ever, under any circumstances complained about using Earth-based time units to describe cosmic age scales.

What is a 'cosmic age scale'??

Since you went through the first 75 years of your life without complaining about it - until you got to this thread - your goal here is just to be an annoying contrarian troll.

JPP is not 75 years old, Sybil.

 

[Into the Night]

We have a fairly good handle on the expansion rates of the universe, so we just run the clock backwards until the universe reaches it's initial hot, ultra dense state.

The universe has no known boundary. What is 'expanding'??

 

[Into the Night]

We only know when the universe began to inflate

The universe is not a tire.

and expand from an initially hot, dense initial low-entropy state 13.7 billion years ago.

The universe has no known boundary. What is expanding? Where are you getting this magick number from?

We don't understand physics at Planck-density, so in principle the initial state at Planck-density could have existed longer than that.

You are not discussing physics. Religion is not science.

I just don't think it could be infinitely old, since that supposition seems to be irrational, illogical, and mathematically non-sensical.

Why? Because you can't get your head wrapped around the concept of infinity?

 

[gmark77]

This is simple.

Infinity is uncountable.

Counting requires a numerical origin point and a numerical end point.

There is no origin point in an infinitely old universe to count forward from until it reaches today.


The arrow of time in physics is based on the Past Hypothesis - that there was a fixed time in the past having an initial low entropy state which evolved to a higher entropy state today. That concept is not supporting an infinitely old universe

Even in infinite series it is possible to deal with finite sums within the series.

Why is any ONE specific point along an infinite time line "impossible"?

Drop someone onto an infinite plane and they will have a point location. Despite the fact that the point has no ability to reference to a boundary.

Maybe the more important question to ask here is: what do you mean by "today"?

"Today" does not contain within it any reference to anything but "before today" and "after today". Like arbitrarily defining "sea level" for all our altitudes does not mean one needs to know the radius of the planet earth.

 

[Into the Night]

We only know when the universe began to inflate and expand from an initially hot, dense initial low-entropy state 13.7 billion years ago.

Who is 'we'? Are you having a schizophrenic episode again?
The universe has no known boundary. What is expanding?
The universe is not a tire.

We don't understand physics at Planck-density, so in principle the initial state at Planck-density could have existed longer than that.

Buzzwords discarded.

I just don't think it could be infinitely old, since that supposition seems to be irrational, illogical, and mathematically non-sensical.

Nothing about the Theory of the Continuum is illogical and it does not violate any mathematics. There is no paradox.
It is not a theory of science.

The Theory of the Big Bang requires a trigger for the Big Bang. That trigger must necessarily exist OUTSIDE of the 'universe' being created, there what is created is not a universe. To call it a universe creates a paradox.
It is not a theory of science.

 

[Into the Night]

Even in infinite series it is possible to deal with finite sums within the series.

Quite right. Your example that you gave is very good.

Why is any ONE specific point along an infinite time line "impossible"?

Obviously, it isn't.

Drop someone onto an infinite plane and they will have a point location. Despite the fact that the point has no ability to reference to a boundary.

Absolutely. Basic geometry.

Maybe the more important question to ask here is: what do you mean by "today"?

"Today" does not contain within it any reference to anything but "before today" and "after today". Like arbitrarily defining "sea level" for all our altitudes does not mean one needs to know the radius of the planet earth.

The term is rather meaningless, since a universe has no day or night.
For sea level, that is simply an assignment. The sea is not level! It doesn't even stay at the same 'sea level'!

 

[Hume]

Older, and Aristotle did not make this argument.

Aristotle did. And you have no fucking idea what Aristotle said about anything.

 

[Hume]

Unit error. Time itself is not a quantity, Hugo.

go to hell you piece of shit troll

 

[Hume]

So if time and space didn't exist until some finite period in the past

Not what I said.

 

[Hume]

Reaching back prior to the Big Bang and trying to add a timeless and spaceless pure 'nothingness' to the history of the universe is a religious concept, straight out of Genesis.

Also nothing to do with my argument.

 

[Cypress]

Even in infinite series it is possible to deal with finite sums within the series.

That's not what's being discussed. What's being discussed is how you can go through an infinite amount of time before somehow are arriving at today. An infinitely old universe is not bounded at an origin point, and it's not an issue of counting a finite series.

 

[Hume]

What's being discussed is how you can go through an infinite amount of time

Fine. But this is not my argument.

 

[Cypress]

What is a 'cosmic age scale'??

JPP is not 75 years old, Sybil.

^^ So, after dozens of posts you still cannot precisely explain how we arrived at the present time if the universe had to somehow pass through an infinite amount of time before today. The fact you are studiously dodging an explanation is very telling.

All you can do is complain about the use of Earth based time units, something you never complained about before in your life until this thread. When cosmologists told you previously the universe was 13.7 billion years old, you never complained about the time units they used. You knew exactly what they were talking about.

 

[Cypress]

That defines time in a manner than I admittedly can't imagine.
I can only envision time as a continuum in which every moment has a before and after,
and that can only be infinite.

We also seem to define the "universe" differently.

To me it's the all-inclusive everything
and not just the currently expanding flux of matter and the space in which it resides.
That's why there can only be one universe by the definition that I apply.

To me, it's both time and space without boundary,
simply because I can't imagine a boundary with nothing outside of it.

This is conceptual, not mathematical.
Mathematics apply within the context that they're applied,
but concepts don't necessarily lend themselves to explanations.
We can imagine inexplicable concepts.
We can imagine more easily and more broadly than we can explain,
but finite isn't something that I can even imagine.....for an all-inclusive universe.

To me, saying the universe is infinitely old, without explaining how we passed through an infinite amount of time to get to the present is invoking a miracle.
From a strictly logical and mathematical perspective, it would be truly miraculous to have an uncountable, infinite, and unbounded amount of time in the past, prior to arriving at today.

 

[Cypress]

Fine. But this is not my argument.

In physics, the Guth-Vilenkin theorem is a proof which mathematically demonstrates that in an expanding universe, there has to have been a spacetime boundary in the past - i.e., this universe cannot be infinite in age and must have a beginning.

That makes sense to me.

I think trying to assert the universe is eternal and infinite in age is invoking a miracle.

The fact that after 150 posts no one has been able to precisely explain how we arrived at today if there was no beginning, and we had to pass through an infinite and uncountable amount of time before the present, just makes the assertion seem even more miraculous.

 

[Hume]

In physics, the Guth-Vilenkin theorem is a proof which mathematically demonstrates that in an expanding universe, there has to have a spacetime boundary in the past - this universe cannot be infinite in age and must have a beginning.

I really cannot discuss physics.
There are very few physicists capable of discussing cosmology.

 

[Hume]

I think trying to assert the universe is eternal and infinite in age is invoking a miracle.

I never made that assertion.

 

[Hume]

The fact that after 150 posts no one has been able to precisely explain how we arrived at today if there was no beginning,

You ignored every post I made.