Dr. Rajendra Gupta is a physics professor at the University of Ottawa who was in the headlines a few months ago for his assertion that the universe might be at least twice as old as we realize. He’s back at the radical reshaping of physics with his latest paper, which proposes that we can do away with dark matter and dark energy. Currently, these invisible substances are thought to make up something like 70-90% of our universe, depending on who you ask. But they’re invisible, undetectable, placeholders for some force or particle that can make the math work out. As an alternative, Gupta proposes modeling the universe with two ideas in mind. One, that the constants of nature are not, in fact, constant and two, that the red light shift seen in the cosmos that is considered to be a signature of expansion is actually the fingerprint of “tired light.” Together, these concepts allow him to recalculate the mechanics of the universe without relying on dark matter and dark energy, which is pretty cool. We talk about the impetus for this work, the meaning of tired light, why expansion isn’t going away any time soon, and the future of physics.