There are very few things that can be proved rigorously in condensed matter physics.
Remember that no piece of honestly conducted research is ever wasted, even if it seems so at the time. Put it away in a drawer, and ten, twenty or thirty years down the road, it will come back and help you in ways you never anticipated.
The people who do make big discoveries are the ones who somehow manage to free themselves from conventional ways of thinking and to see the subject from a new perspective.