Phenomenological Nuclear Theory

[Pythagorean]

When I took modern physics (undergrad), we learned nuclear theory through a phenomenological model of the nucleus. I was just curious whether there are more formal models and whether they draw directly on the postulates of quantum mechanics or not. It's been two years since I took the class, so I'm a little rusty.

If not, is it assumed impossible or just undiscovered?

 

[ansgar]

what about the shell model for instance?

 

[Pythagorean]

The Liquid Drop model is the one I'm referring to. I guess I'm wondering if it's been replaced. Does the shell model render the liquid drop model obsolete?

 

[ansgar]

the drop model can't explain excited states etc, it is a classical model

 

[petergreat]

The Liquid Drop model is the one I'm referring to. I guess I'm wondering if it's been replaced. Does the shell model render the liquid drop model obsolete?

As far as I know, the two models describe different aspects of the nucleus. Shell model predicts nuclear spin and excitation levels, but it can't replace the liquid drop model when you need to consider the overall shape of the nucleus. For example the semi-empirical nuclear mass formula is mainly derived from the liquid drop model (plus quantum-mechanical terms such as asymmetry and parity). Also, the shell model has limitations. It only works well if you are dealing with excitations that are not too high, in nucleons not too far away from the "magic numbers". In the end, both of them are approximations (i.e. phenomenological models) rather than fundamental theories.