Focus of the present-day nuclear structure theory is on determination of nuclear effective interactions and/or energy density functionals. The term "effective" pertains here to the fact that they are used in a restricted phase space (shell model) or neglect correlations (mean field), and hence cannot be identical to interactions in the vacuum. Both types of methods are at present very well developed and operational, however, much more work is needed to find the best possible interactions to be used within them.
First-principle derivations of effective interactions are currently pursued with increased intensity, however, the task is difficult and requires some time to bear fruit. In the past such derivations were always complemented by phenomenological adjustment to experimental data. There is no doubt that such adjustments will remain the best source of recognizing the main features of interactions, and achieving a precise description. Therefore, future developments in nuclear structure theory critically depend on the availability of data that probe and enhance the most interesting and least known channels of effective interactions. The isospin properties are certainly of that kind, and we hope to get qualitatively new insight in this channel from the new generation rare-isotope facilities that are currently being constructed or planned throughout the world.
During preparation of this talk I have received suggestions
and comments from over 40 of my colleagues and collaborators;
I would like to thank them very much for their help. In particular,
I would like to thank
M. Bender,
K. Bennaceur,
S. Cwiok,
S. Frauendorf,
S. Goriely,
L. Grigorenko,
M. Huyse,
W. Nazarewicz,
S. Pieper,
M. Pearson,
M. Riley,
and
K. Rykaczewski
for sending me files with figures.
This work was supported in part by the Polish Committee for
Scientific Research (KBN) under Contract No. 5 P03B 014 21.