Whew, really fantastic article!
> “In physics, description is explanation” (author quoting his PhD advisor)
Yes, i have always hated this about physics. It is the only scientific field that apparently feels no responsibility to explain “why”, deciding that “what” is sufficient.
I wish the author all success so that i can someday read a satisfying answer to some of the “whys” of physics.
It's not that physics feels no responsibility to explain why, it's that all other fields of science answer the why by punting to some lower level of science that is taken as an assumption until you get down to physics which has nothing lower level to punt to.
Psychology explains why you feel tired by pointing to biology. Biology explains why cells need ATP by pointing to chemistry. Chemistry explains why ATP releases energy by pointing to physics. Physics explains that by pointing to some higher level form of physics like thermodynamics, which points to statistical mechanics, which point to quantum laws. When you get down to a certain level you simply have nothing left to punt to. You simply accept it because it's what's observed and makes reproducible predictions or you don't and go study philosophy or religion or something.
There is philosophy, but common physicists does not like going there, unless for rare cases like the author or Max Tegmark or Roger Penrose...
So they goes round and round, using more and more "dials" to stay within their framework, always kicking the can down the road a bit (its turtles all the way down), but never really answering the core questions...
Yeah you’re right. And also part of it is that I simply don’t know enough deep physics to maybe start to get a more “intuitive” grasp on things.
But on the other hand I do feel there are cases where other fields have true explanations without punting. It’s not all the time but sometimes. My favorite example is evolution. We observe evidence that species evolve over long periods. Why? Natural selection. It’s the entire explanation. And I suppose in some senses it punts on the mechanisms of natural selection - genes and molecular biology rest on physics and chemistry after all. But in terms of the why, why does evolution happen, I feel we have a complete answer that has that feeling of intellectual satisfaction and completeness that is, at least from my lay perspective, lacking in physics.
Or, as the old joke goes:
> Psychology is really biology; biology is really chemistry; chemistry is really physics; physics is really math; and math is really hard.
You could say meta-biology is called chemistry and meta-physics is just called meta-physics.
Description isn't explanation at all. That's bullshit.
Whys are teleological. No one knows why anything.
Hows are working models. And, as per Kuhn, they get updated regularly, but people get attached to them and they often need to die out before progress happens.
But really we're dealing with metaphors in mathematical form. There's likely some underlying ultimate substrate, but it's possible we may never understand it because it just won't fit inside our minds.
You can explain "the sun goes around to Earth" to almost anyone. "Orbits are ellipses" is high school level. Orbital perturbation theory is undergrad, and you've already lost maybe 90% of the population. The Einstein field equations are PhD level, and maybe a few thousand people out of a population of eight billion understand them.
If there's a level beyond that - and there probably is - we won't be able to access it bare-brained. The underlying metaphor may be explainable, possibly, but the math won't be.
And one of the defining features of science is that scientifc metaphors are counter-intuitive. Our brains evolved to understand spear throws, so we've built physics on physical experiences like mass, velocity, direction, and so on.
That gets really strained and broken in both relativity and quantum mechanics. In relativity spacetime is a bendy thing in its own right and 'time' doesn't work like normal clock time. And in QM all you really have are probability clouds that literally don't seem to have a physical foundation interacting with each other in very unintuitive ways.