Thoughts on the scale of the universe?

[Darkstar]

Finite. The universe is no larger than the rate of expansion would allow.

Wrong. Expansion rate does not set an upper limit on the size of the universe.

Any sized universe larger than the currently observed part of universe, up to and including infinitely large, can be accommodated within the currently observed expansion rate.

But unless the expansion rate is infinite, wouldn't it take an infinite amount of time for the universe to become infinitely large, assuming it was even capable of doing so?

[Anomalocaris]

Wrong. Expansion rate does not set an upper limit on the size of the universe.

Any sized universe larger than the currently observed part of universe, up to and including infinitely large, can be accommodated within the currently observed expansion rate.

But unless the expansion rate is infinite, wouldn't it take an infinite amount of time for the universe to become infinitely large, assuming it was even capable of doing so?

No. The universe could have been infinite to start with, before it even expanded. Think of a progenitor universe that consist of infinite number of little units of space. This progenitor universe is infinitely large. Then something happened to it, a phase transition, say. So all of a sudden every one of the infinite number of little unit of space expanded greatly. The universe is still infinite, and consist of infinite number of space units. But each unit has now expanded enormously at its own rate of expansion.

The universe was infinite, still is infinite, but the unit of space we are in expanded greatly at its own finite rate of expansion.

[Darkstar]

But unless the expansion rate is infinite, wouldn't it take an infinite amount of time for the universe to become infinitely large, assuming it was even capable of doing so?

No. The universe could have been infinite to start with, before it even expanded. Think of a progenitor universe that consist of infinite number of little units of space. This progenitor universe is infinitely large. Then something happened to it, a phase transition, say. So all of a sudden every one of the infinite number of little unit of space expanded greatly. The universe is still infinite, and consist of infinite number of space units. But each unit has now expanded enormously at its own rate of expansion.

The universe was infinite, still is infinite, but the unit of space we are in expanded greatly at its own finite rate of expansion.

How can something that is infinitely large get bigger? Wouldn't the infinite number of spaces, no matter how small each one was, take up an infinite amount of space and leave no room for expansion? Infinite is not just 'big beyond comprehension', it is everything, that is why we cannot assign a value to infinity-10^99999999; it would still be too large. If they could still expand, that would suggest that the 'space' the universe is expanding into was bigger than infinity, which is impossible. If you said that an infinite amount of potential space was contained in the singularity, but not infinite mass, and that space was simply becoming less dense with matter as it expanded, being infinite all the way, I'd be willing to believe that much.

[Minimalist]

Thoughts on the scale of the universe?

It's big.

[Whateverist]

While the size of the universe is debated often out of scientific curiosity, philosophically speaking, its scale is lacking in relevance to our lives.

Completely agree. But for the same reason it is just as 'out there' to speculate about the edge of space and time in relation to the one singularity for which we have evidence.

[Jackalope]

Thoughts on the scale of the universe?

It's big.

It's really, really big. No, bigger than that.

[Mystic]

Thoughts on the scale of the universe?

It's big.

HAHA

[Anomalocaris]

How can something that is infinitely large get bigger? Wouldn't the infinite number of spaces, no matter how small each one was, take up an infinite amount of space and leave no room for expansion? Infinite is not just 'big beyond comprehension', it is everything, that is why we cannot assign a value to infinity-10^99999999; it would still be too large.

Infinite is not a concept that has a tangible equivalent in daily life, so it is hard to think clearly about it without making the mistake of trying to shoehorn a model derived from everyday experience into a situation requiring a mathematically sound model.

So to think clearly about infinity you have to use math to help you. In math, infinity has the property of being arbitrarily divisible, and yet each part would remain just as infinite as the whole.

So 1/2 of infinity, or one trillionth of infinity, or one googleplexeth of a infinity, each party would be different from the whole, but yet no less infinite than the whole. Similarly, duplicate inifinity a googleplex time and the collection of all product from the replication would be different from before, but no more infinite.

This is conceptually how an infinite universe can expand. Put a ruler in space along any direction, and the ruler can go on literally forever. The universe is infinite in that direction. But look at each inch on the ruler. Each inch division on that ruler can grow, until it is now 2 inches long. The ruler still goes on forever. The universe is still infinite. But every portion of it is now twice as large.

If they could still expand, that would suggest that the 'space' the universe is expanding into was bigger than infinity, which is impossible

Again, you are tripping yourself up by forcing a mental image from daily life in which everything exists in a small part of space, into an inappropriate analogy for all of space itself. Space does not expand into anything. Space s everything. Space just expands by becoming bigger, without displacing anything. All that ever is is getting bigger. It is not getting bigger by taking up space belong to something else before. It is creating more space where no existed before. Space can be infinite, can can always have been infinite, yet try to visualize every unit of space as spawning more space. This is how infinite space can expand.

If you said that an infinite amount of potential space was contained in the singularity, but not infinite mass, and that space was simply becoming less dense with matter as it expanded, being infinite all the way, I'd be willing to believe that much.

The singularity vision of the beginning of the universe only applies to the visible portion of space. It is only looks like a singularity because our physics breaks down somewhere before things got really small. The origin of the visible portion of our universe probably had some dimension, in the neightborhood of a planck length, or about 10^-35 meters. It may not have quite been infinitely small.

Along the same vein, the universe that is currently beyond our visible horizon, not all of it may have fitted into the same notional singularity.

Go back to the divide infinity by googleplex concept. What our physics imperfectly descibes as the singularity that spawned everything we can see now may have been part of a larger, perhaps infinitely larger, construct that began an expansion at the time we call the Big Bang.

[Darkstar]

Infinite is not a concept that has a tangible equivalent in daily life, so it is hard to think clearly about it without making the mistake of trying to shoehorn a model derived from everyday experience into a situation requiring a mathematically sound model.

So to think clearly about infinity you have to use math to help you. In math, infinity has the property of being arbitrarily divisible, and yet each part would remain just as infinite as the whole.

So 1/2 of infinity, or one trillionth of infinity, or one googleplexeth of a infinity, each party would be different from the whole, but yet no less infinite than the whole. Similarly, duplicate inifinity a googleplex time and the collection of all product from the replication would be different from before, but no more infinite.

This is conceptually how an infinite universe can expand. Put a ruler in space along any direction, and the ruler can go on literally forever. The universe is infinite in that direction. But look at each inch on the ruler. Each inch division on that ruler can grow, until it is now 2 inches long. The ruler still goes on forever. The universe is still infinite. But every portion of it is now twice as large.

Go back to the divide infinity by googleplex concept. What our physics imperfectly descibes as the singularity that spawned everything we can see now may have been part of a larger, perhaps infinitely larger, construct that began an expansion at the time we call the Big Bang.

hmmm...I've occasionally thought about 'greater' infinity (infinity times two is still infinity, but it is bigger at the same time) and 'lesser' infinity (infinity divided by two is still infinity but smaller at the same time), but they only mattered as different from regular infinity when compared to other infinites. I understand how you are using the math, but I can't seem to visualize 'greater' infinity in a real scenario. I'm not saying that you are necessarily wrong, just that I can't picture a 'greater' infinity as compared to regular infinity outside of abstract mathematics.

[IATIA]

There is an infinite set of real numbers between 0 and 1. There is exactly the same amount between 1 and 2. Logically this suggests that there must be twice as many between 0 and 2.

Picture an infinite number of infinite universes within an infinite void.