#497 – Biggest Mysteries in Physics: Antimatter, Dark Energy & ToE – Don Lincoln

[guitar playing] In describing the search for theory of everything in physics, you describe the history of physics can be told effectively as a kind of history of unifications.

There's this centuries-long quest to show that, uh, these distinct phenomena are actually linked by some unified underlying principles, uh, even starting with Newton, that you can think of the effort of physics as one is trying to unify-

Mm-hmm

...

the laws of nature.

So I was wondering if we could talk through the history of unification-

Sure

... that lens of physics.

There are, of course, lots of different ways to do physics, but the, the way that I would say that particle physicists, cosmologists do is they are trying to, to really find basically the underlying principles that govern the laws o- of nature.

If we go back, say, to the, I don't know, 1650s or so, uh, you're the most brilliant person around, and you've noticed two things.

One you've noticed is that when you trip, you fall.

That is the nature of gravity that, that we all experience day to day.

But then there's sort of astronomy, where you look out at the heavens and you see the stars march across the sky.

You see the planets move through the stars.

And there, th- that seems to have absolutely nothing to do with what happens when you drop your sandwich and, and the dog grabs it from you.

So-

[chuckles] Yeah

...

the brilliant thing was when Newton looked at that and he thought about maybe the moon is falling, but it's missing the Earth.

So what we had is that in maybe 1650, you had what we might call the laws of celestial gravity, the gravity that governs the heavens, and terrestrial gravity, the gravity that is here on Earth.

Now, we don't think of it that way anymore.

We think of it as just gravity.

But at that time, that wasn't at all obvious.

And in fact, if you look in the books, Newton's theory is Newton's law of universal gravity.

The universal is there, and the reason is, is because he realized these two things that seemed to have nothing to do with one another were indeed one and the same.