# Aliens, subatomic particles, and the limits of physics

Imagine some aliens for whom our solar system is an atom in their universe. Also, suppose their physicists are studying the Earth like our physicists study subatomic particles in our universe.

One can imagine them discovering some mass flowing/moving on the surface of this Earth, and it turns out that this moving mass corresponds to all the Earth’s animals and humans. Since we are too small for them to individually count us, to their instruments we just appear like a flowing mass moving around the surface of the Earth. As a result, they develop theories that model this movement or flow.

I assume that they can find some periodic events, like the great migration of the Wildebeest in Africa:

This means that their equations will have some periodic components. However, the equations have to be a bit more complex than that, since the timing of these annual migrations isn’t totally predictable: “The timing of their migration in both the rainy and dry seasons can vary considerably (by months) from year to year.” (Wikipedia)

What’s more interesting though, is what happens when their equations try to predict the flow of humans across the planet. Most of the population is located in cities, but there is a lot of movement on a somewhat periodic basis. For example, some events cause the movement of tens or hundreds of thousands of people:

- With a period of 4 years, we have the Olympics and the Soccer World Cup
- With a period of 1 year, we have the Super Bowl in the US and Soccer cup finals in Europe
- With a period of 1 week, we have football and soccer games in cities around the world

These are somewhat predictable, and could be incorporated quite easily into the model, except for the fact that they are sometimes pre-empted by other events. For example, the 1940 and 1944 Olympics were canceled due to World War II. How would the model account for that? Or how would it account for the fact that on some weekends, games are canceled due to strikes or other phenomena?

And how would it account for the fact that once in a while, wars break out between humans, and thousands and sometimes millions of people move around the surface of the Earth?

I assume that they would take care of these unpredictable-to-them anomalies using something similar to what our physicists use: the wave function.

“Although ψ is a complex number, |ψ|² is real, and corresponds to the probability density of finding a particle in a given place at a given time, if the particle’s position is measured.”

That is, we can’t tell where a subatomic particle is with certainty, so we have a probability density function for its location. Similarly, the aliens wouldn’t be able to predict the exact location of “human mass” with certainty, so they would have a probability density function for its expected location.

However, remember that if the aliens could hear and understand our newscasts and followed the goings-on in the human world, they might know that a baseball strike means no flow of humans to baseball stadiums this Sunday. Or they might know that the assassination of an ambassador means war between two rival countries resulting in a high flow of humans in the next few days or weeks.

Since they don’t know all the underlying reasons behind the events, they are stuck with the probabilistic model. Could something similar be happening with the probabilistic models we use to describe our subatomic world?

This sort of idea has been proposed before, and it’s referred to as the hidden variable theory. It turns out there are several criticisms and theorems around hidden variables, one of the most famous being Bell’s theorem. While it closes the door on local hidden variables, “it leaves the door open for non-local hidden hidden variables” [Wikipedia]

The claim in this post is not that subatomic particles in our world contain sentient beings, and if only we could understand these beings, we could accurately predict their behavior without probabilistic models. What this post is claiming, and what the analogy in this post is trying to show, is that it’s possible that there may be some information about the subatomic world which is unobtainable to us, and which, if we knew it we could predict certain events without the need for probabilistic models such as the wave function.

*Originally published at **https://andrewoneverything.com**.*