Before he died, Einstein was working on a theory of everything. It aims to combine all the forces in the universe into one beautiful, mathematical equation to explain everything.

That equation remains incomplete, but physicists like Michio Kaku are charging ahead using new scientific observations from gravitational wave detectors and particle accelerators.

Kaku is a professor of theoretical physics at City College of New York and the author of a new book The God Equation: The Quest for a Theory of Everything.

He joins us to talk about the work by modern-day physicists to solve the equation, the controversy surrounding the core of the problem’s solution and how understanding this equation can help answer big questions of the universe, like what happened before the big bang.