Tomita–Takesaki theory is a way of describing the way different parts of the universe interact with each other. It's a type of mathematical theory, so it's a bit hard to explain in simple terms. Basically, Tomita–Takesaki theory says that there are 'quantum fields' in nature that tell particles and forces how to behave. They also tell particles and objects how to interact with each other, so the idea is that if we can figure out the fields and how to control them, we can better understand the universe.