Imagine, for a moment, that you are a physicist doing research in the early years of the 20th century. Your field of study is advancing by leaps and bounds, including new theories about subatomic particles. Only there seems to be no way to test your ideas because you lack the tools needed to conduct the appropriate experiments. Then, some of your colleagues come up with an idea for an ‘accelerator’ that visibly records the results of particles colliding with other particles. It is an amazing and complicated machine that was invented and refined over a number of years by bringing together many theoretical and technological advances (Bryant, 1994). But once the accelerators start being built you are in possession of a tool for revealing the invisible. You are able to test your hypotheses by running practical experiments. You can even explore new theories by simulating some of the conditions of the universe just moments after the Big Bang.