Neil deGrasse Tyson

Neil deGrasse Tyson always seems to have a theory about something. As he should, since he’s the most recognizable astrophysicist on planet Earth. He’s been on countless television shows, hosts his own podcast about all things space and science, and has a Bachelor of Arts in Physics from Harvard and a Ph.D. in Astrophysics from Columbia.

In March 2021, Tyson appeared on "The Late Show with Stephen Colbert" to promote his latest book, "Cosmic Queries: StarTalk’s Guide to Who We Are, How We Got Here, and Where We’re Going." The book focuses on the really big questions about the universe and our place within it. Tyson begins his conversation with Colbert by discussing how it will all end — "all" being the universe. Colbert interrupts and asks him to explain how the Earth will end in one easy sentence, and Tyson obliges. According to the famed astrophysicist, the sun will eventually expand, and Earth will get so hot that the oceans boil off and evaporate into space. The planet will become a burning husk that gets pulled to the sun’s surface and vaporizes. So, buy stock in sunscreen.

But this is boring to Tyson, apparently, because he says scientists already know how the Earth ends. The bigger questions, like how the universe ends, are what keep him up at night.

Neil deGrasse Tyson and the Big Rip

Tyson explains the "Big Rip" theory is based on cosmic expansion, which says the universe continues to expand after the "Big Bang," and all of the energy and matter within it has remained constant. As the universe expands, the density of all that energy and matter must become thinner.

Tyson says scientists don’t really know why it’s happening, but they know dark energy is causing it to happen, and it is measurable. The expansion rate will eventually outstrip the gravitational forces that hold things together, even overcoming the molecular bonds that hold our bodies together. Those forces will continue to gain strength as the universe expands because as it gets bigger, more vacuum is created. This dynamic will continue until it "rips" or separates our molecules and atoms apart, including the very fabric of space and time.

During the same interview, Tyson dips briefly into the wildly confusing topic of the multiverse and the fact that there might be layers of them stacked on top of each other. Because the existence of a single multiverse, let alone layers of them, isn’t a maddening enough topic.