In this blog we’ll discuss what the universe truly is based on its size. There are only 2 possible answers and that is finite or infinite universe.

(I was researching randomly and I found some videos on this topic, I tried to explain everything in my own words. Yes you can say I’m the most science loving commerce student alive)

Finite Universe-

So the earth is roughly 4.5 billion years old and the fastest information can travel is at the speed of light, therefore the “observable universe” should be of a radius of 4.5 billion light years.

Though there is a twist. Since we know that the cosmic radiation i.e the universe is ever expanding, therefore the farthest we can see is actually 45 billion light years.

Now, a finite universe means that the space is finite. It can be extremely huge and certainly larger that the observable universe but it is finite.

Here’s a problem, a finite universe must have an edge. So what’s outside the edge?

Doesn’t the universe in and itself means “everything”? So how can there be something out of “everything”?

/physics entering…(this part is a bit tough to understand and even explain)

Hypersphere:

There is a possibility that the universe is finite but doesn’t have any edge. Sphere’s come into picture. Hypersphere as much as I understood is a 4 dimensional sphere.

If we take a spaceship and travel in any random direction, we could reach the same place we started just like on earth. Just it would take a lot more time.

How is this possible? I don’t know the actual physics behind but putting it simply. Mass creates gravity by bending the fabric of space time. Now this could lead to everything bending back on itself which is complicated to understand (even I didn’t understand but that’s exactly what I learned).

Just understand that old men with beard and physics came up with these theories so they make sense mathematically at least.

This is one possible type of finite universe and it would be at least 1000 times bigger than the observable universe. (It could be trillions of times bigger too)

Hyperdonut:

This too is like a hypersphere but in the shape of a donut.

Things get further complicated here. Now if we travel in different directions, we’ll reach the same place in different time. Which also means that at one angle you can see me being born and at a different angle you can see me die.

Due to its strange geometry it could be just a few times larger than our observable universe. Also, it could be trillions of times bigger.

Infinite Universe-

Now, this is my favorite part. In an infinite universe, there is something everywhere. So does this mean it had been like that since forever.

We have quite some evidence that big bang happened so does it mean that there was nothing everywhere and then there is something everywhere.

Also we have evidence that the universe is ever expanding so how can a thing that is infinite expand more? This is known as the paradox of infinite universe.

The best part about this is that if this is true. There could be a galaxy where you will be living your life same or with minor and major changes.

This is because if there is truly infinite space. Then if we travel far enough, then you could meet many versions of you. Mathematically, there will be infinite versions of yourself because matter can only be arranged in finite way. Though this number would be huge and even if there are infinite versions of you, you’ll probably never meet them since they are just too far.

This is the biggest paradox of infinite universes.

~ It just feels good to know that there is a Vedant who is happier at the very least.

Keep Growing.