I would like to write a research paper using restructuredtext, is it possible to have the two-column style inherent to this kind of document? I looked at the specifications but apart using a table which will be a real pain I haven't been able to find an alternative.
You can output 2-column in any of the formats docutils outputs.
If what you want is a 2-column ReST source then it's much harder.
Since there are no pages, it may not even make sense (imagine if the columns are 5000 lines long ;-), so I will assume you mean in the output, be it HTML, PDF or whatever.
For PDF, using rst2pdf, it's trivial, you only need to use the -s twocolumn option.
For HTML, it's a CSS thing, and I am sure google can help you.