Dennis Whyte

E equals mc squared.

Okay, so what does this mean?

It tells you that the amount of energy that is liberated in a particular reaction when you change mass has to... Because c squared, that's the speed of light squared.

It's a large number.

It's a very large number, and it's totally constant everywhere in the universe, which is... Which is another weird thing.

Which is another weird thing, and in all rest frames.

Actually, the relativity stuff gets more difficult conceptually until you get through.

Anyway, so you go to that and...

And what that tells you is that it's the relative change in the mass will tell you about the relative amount of energy that's liberated.

And this is what makes fusion, and you asked about fission as well too, this is what makes them extraordinary.

It's because the relative change in the mass is very large as compared to what you get like in a chemical reaction.

In fact, it's about 10 million times larger.

And that is at the heart of why you use something like fusion.

It's because that is a fundamental of nature.

Like you can't beat that.

So of whatever you do, if you're thinking about, and why do I care about this?

Well, because mass is like the fuel, right?

So this means gathering the resources that it takes to gather a fuel, to hold it together, to deal with it, the environmental impact it would have.

And fusion will always have 20 million times the amount of energy release per reaction that you get of those.

So this is why, you know, we consider it the ultimate like environmentally friendly energy source is because of that.