Thoughts from a Planetarian: That's Just the Way It Is

It shouldn’t be a surprise to anyone who has met me that I was a “why?” kid growing up. I have many fond memories of poring over books like The Way Things Work, The Dorling Kindersley Visual Encyclopedia, and my favorite, Stephen Biesty’s Incredible Cross-Sections then barraging my poor mother with questions like, “Why does this printer use a laser?” or “If jet engines have fire in them, why don’t they melt?” She was remarkably patient and considerate with me, but at a certain point would have to resort to “I don’t know” or “I think that’s just the way it is.” While it may have felt disappointing at the time to leave my curiosity unchecked, she was actually teaching me how science works.

Science seems to tell us that every question has an answer. No matter how complex the question or convoluted the system, if we just probe deeper or develop better tools we can make sense of everything. Everything happens for a reason—even in cases of chance or coincidence, science can account for that, too. The Scientific Method is our best tool for understanding our place in the Universe, and anything that seems mysterious is simply a challenge humans can’t figure out, yet. Every “why?” eventually finds a matching “because...”

But there are questions for which the answer is simply, “That’s just the way it is.” Questions such as “Why is there energy?” or “Why is the circumference of a circle twice the radius times pi?” are simply so foundational that we can’t even imagine what a Universe would be like if they were not the case.

There’s a whole set of physical constants that just are. We can measure them, and refine our measurement, but at a certain point, they simply are what they are. The standard model of particle physics is full of these. Sure, there might be some deeper theory that connects them all (lookin’ at you M-theory), but at a certain point we’re gonna run into the same problem. The Universe is probably made of overlaid quantum fields because it is—there’s no rhyme or reason as to why.

An example that comes up all the time is with magnets and magnetic fields in general. Any complete definition of how a magnet works starts with a statement like “electrons are tiny magnets” (more technically: they have spin magnetic moment), which is extremely frustrating to be told as a visitor if you’ve just asked how magnets work. At best, “magnets work because they’re made of smaller magnets” is just a way of saying “that’s just the way it is” with extra steps, while at worst it comes off as insultingly condescending (for more on magnets watch this).

Science has come far from its inception. We went from Plato’s Geometry of Elements, which, while pretty, explains pretty much nothing. To Atomic Theory, which explains most things- nearly everything that we experience. To Quantum Field Theory, which has distilled the universe to a set of particles and equations that can explain nearly everything except the reasons for their own existence (and gravity - oops). Is there a deeper connecting theory? Maybe. Will it completely answer all of our remaining questions? Almost certainly not.

At the end of it all we won’t cross some finish line and be done with science. There’s always going to be things we can’t explain, and at the end of the day, all science has done is push the just because further and further away. Why bother? Why keep making things more complicated if the end result is the same?

QFT (with the help of General Relativity for the gravitation bits) doesn’t model the Universe perfectly, no, but it’s the best we have so far. It might not have answers to every question, but they have answers to most of them, and we can say pretty confidently that for the rest the answer is probably, “And that’s the way it is.”