alt Hacker NewsDoesn't that imply our theories are "good enough" for all practical purposes? If they're impossible to empirically disprove?
Replies
Maybe? We seem to be able to characterize all the stuff we have access to. That doesn't mean we couldn't say produce new and interesting materials with new knowledge. Before we knew about nuclear fission we didn't realize that we couldn't predict that anything would happen from a big chunk of uranium or the useful applications of that. New physics might be quite subtle or specific but still useful.
The point is not to make better predictions of the things we already know how to predict. The point is to determine what abstractions link the things we don't presently understand--because these abstraction tend to open many new doors in other directions. This has been the story of physics over and over: relativity, quantum theory, etc, not only answered the questions they were designed to answer but opened thousands of new doors in other directions.
Yes, for all practical purposes. This is the position of physicist Sean Carroll and probably others. We may not know what is happening in the middle of a black hole, or very close to the big bang, but here on Earth we do.
"in the specific regime covering the particles and forces that make up human beings and their environments, we have good reason to think that all of the ingredients and their dynamics are understood to extremely high precision"[0]
The theories don't answer all the questions we can ask, namely questions about how gravity behaves at the quantum scale. (These questions pop up when exploring extremely dense regions of space - the very early universe and black holes).
There's still huge gaps in our understanding: quantum gravity, dark matter, what happens before planck time, thermodynamics of life and many others.
Part of the problem is that building bigger colliders, telescopes, and gravitational wave detectors requires huge resources and very powerful computers to store and crunch all the data.
We're cutting research instead of funding it right now and sending our brightest researchers to Europe and China...
I think the problem is that GR and QFT are at odds with each other? (I am not quite versed in the subject and this is my high-level understanding of the “problem”)
Absolutely not. Newtonian physics was 'good enough' until we disproved it. Imagine where we would be if all we had was Newtonian physics.
If I have to make a guess, we are at the level of pre-copernicus in particle physics.
We are finding local maximums(induction) but the establishment cannot handle deduction.
Everything is an overly complex bandaid. At some point someone will find something elegant that can predict 70% as good, and at some point we will realize: 'Oh that's great, the sun is actually at the center of the solar system, Copernicious was slightly wrong thinking planets make circular rotations. We just needed to use ellipses!'
But with particles.
Typically whenever you look closely at an object with complex behavior, there is a system inside made of smaller, simpler objects interacting to produce the complexity.
You'd expect that at the bottom, the smallest objects would be extremely simple and would follow some single physical law.
But the smallest objects we know of still have pretty complex behavior! So there's probably another layer underneath that we don't know about yet, maybe more than one.