Interview with the author Katie Mack

How do scientists think the Universe will end?

The theory most currently accepted is ‘heat death’. The Universe is expanding, galaxies are getting farther apart, so over time there will be fewer interactions between galaxies and less gas brought in to form new stars. Stars will fade and die, particles will decay and black holes will evaporate. It’ll be a Universe that’s empty, dark and cold, where the only thing left is waste heat from the destruction of everything. In the book I explore other possibilities, but none is a ‘happily ever after’ scenario.

How might humans experience the end?

In the ‘big rip’ scenario you’d watch stars at the Galaxy’s edge drift away, the Milky Way fade out in the night sky and Earth drift from the Sun before being torn apart. You could get into a space capsule and wait it out but then, close to the end, your space capsule itself would get ripped apart and, finally, your own atoms.

What astounds you most about the Universe?

Even though we’re insignificant beings, we can understand what the Universe is made of and its evolution, and we can extrapolate into the future. When you look out into the cosmos, you’re looking into the past because light takes time to travel, so you can observe a galaxy a billion lightyears away and see the light that came to us a billion years ago. We can see a Universe that’s still on fire from the heat of creation. I’m proud that humans figured that out, and I’m lucky to be in a cosmos where we can learn and see all that.