I Lied To You!!

Please Note: This is a very nerdy post and if you're not into science or space or whatever then read with caution. Also credits go to my father for the balloon analogy thing.

Alright, let's talk about the size of the universe.

I know I've written about this before, considering that space is really really cool and I basically center most of my blog posts around the topic of the galaxy. But I think I lied to you.

The universe is not infinite. This is something that I've stated many times before which makes me feel slightly stupid and uneducated, but hey. I never really know what I'm talking about, anyway.

So how big is the universe actually? It's a difficult question to answer, as I've discovered. Here's what I know:

Although the universe is 13.8 billion years old and nothing travels faster than the speed of light, the universe is actually bigger than 13.8 billion light years. (A light year, by the way, is the distance light travels in one year). This is because space is actually STRETCHING.

Imagine two dots on a balloon that's blowing up. Even if the two dots try to stay still, they will move apart from each other as the balloon expands. That's just how it will happen, because the balloon is getting larger so the dots are spreading apart along with it.

Two ants walking away from each other on a balloon
Courtesy of my amazing photoshop skills
Also this balloon these ants

Now imagine two ants on the balloon walking away from each other at 5 miles per hour. The ants' relative speed will be 5 miles per hour plus the speed of the expanding balloon, which overall will be faster than 5 miles per hour. Basically their walking speed is added to the balloon-expanding speed.

In this same way, the universe has grown faster than the speed of light to be about 91 billion light years in diameter.

In other words, the universe is not actually infinite, nor is it's size simple to calculate, because space is ever-expanding like a giant balloon. I think this knowledge is ridiculously annoying but also extremely interesting. It's sort of relevant to the idea that the Earth is always moving around the sun and rotation around it's axis simultaneously. We're all moving. We're all spinning in circles, we're all tracing repetitive yearly rings around a giant ball of fire, and we're all inflating with the universe.

The universe isn't actually infinite. Sorry about that.