Cordoba is a +1 million inhab with great universities and quality of life, much like my home city (Rosario), but if you are looking down south, and since you mention it... Bariloche is not at all a bad option.
Since you are looking for math and science, there is the Instituto Balseiro, where the best argentine Nuclear Physicist come from. It's an elite place to study different carreers and masters.
http://www.ib.edu.ar/
Also, Bariloche is sorrounded with the most beautiful mountains, lakes and woods in our country.