What Classical Physics Problems Remain Unsolved in Modern Physics?

[Maxwell's Beard]

I like to see you gents post up some classical physics problems that have yet to be answered by modern physics?

Anyone?

 

[f95toli]

Depends on what you mean by "questions".
There are plenty of problems that only involve 19th century physics that we can't solve (or can only find approximate solutions to) because they are so complicated, e.g. fluid dynamics where the basic equations (Navier-Stokes)have been around for a very long time; but we still don't fully understand phenomenon like turbulence because even the fastest computers in the world can't handle turbulent phenomena (without approximations) around real aircraft (which is why we still use wind tunnels).
Climate modeling is another example, the approximations are quite good and using fast computers climatologists can make rather accurate predictions on a global scale; but local predictions are very,very hard.

Anyway, no one expects to find any "new" physics in these problems. finding more accurate solutions essentially boils down to using better and faster computers (and better numerical algorithms); occasionaly there are surprises but nothing that fundamentally challenges our understanding of the world. That said, chaotic phenomena are still very interesting and challenging.

Also, the reason why we have "modern physics" is because classical physics failed to answer some very fundamental questions. Hence, problems that are still around belong, almost by definition, to modern physics.

 

[Maxwell's Beard]

Also, the reason why we have "modern physics" is because classical physics failed to answer some very fundamental questions. Hence, problems that are still around belong, almost by definition, to modern physics.

That is a very good way of describing it. I like that point of view. I'm not as sure as you are that there is no "new physics" to be found by repondering old questions, though. I think it an interesting idea that old experiments should be conducted in the same manner as they were, and from a retrospective point of view.

Does this actually happen? Have old experiments been tried in a modern light to see if some aspects, even small may been overlooked or were even undetectable at the time? Or have scientists taken for granted the old proofs of experiments and moved on to study only the new outcomes of observable effects, without ever looking back? It would be an easy thing to do, humans being human and all.

 

[meopemuk]

I like to see you gents post up some classical physics problems that have yet to be answered by modern physics?

Anyone?

Take a look at this thread:

https://www.physicsforums.com/showthread.php?t=182448

Eugene.