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Physics has set itself quite the task.

The job is to explain the whole universe, everything inside of it, and all of its tubing and throwing.

Usually, we think of that in terms of the matter, the stuff, and the forces, how that stuff

interacts. So, when we count our progress towards the big goal of physics, we sometimes think

about the number of particles and the number of forces.

We reduce that number when we break open matter to see what it's made out of, or when we

unify forces, like would we merged electricity and magnetism into electromagnetism, and

then later added the weak force to make the electro-weak force.

Sorry, magnetism.

Eventually, we hope, we'll get down to one particle and one force that explains everything

that happens.

But what if there's a better way?

Maybe forces are intuitive to us, part of the stories we tell about what we see with a simple

intuitive analog in our experience. But what if they aren't a natural fit to the real

mechanisms of the universe itself? What if forces emerge from something else? Today on the pod

we'll talk about something we've mentioned many times

in many contexts. It's time to dive in and talk about the mysterious quantity that has no

analog in our intuitive experience, but seems to dominate in the events of the universe.

Action. And specifically, why the universe seems to minimize it.

Welcome to Daniel and Kelly's extraordinary minimal universe.

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