Katie Mack manages two unexpected feats with her new book, The End of Everything (Astrophysically Speaking). First, she writes about the end of the universe with a jauntiness that makes it not really that depressing. And second, she takes concepts in cosmology, string theory, and quantum mechanics and makes them accessible. This instant chat gift will be familiar to the 360,000 followers of Mack’s Twitter feed – @AstroKatie – making the 39-year-old cosmologist and assistant professor at North Carolina State University one of the most popular voices on science.
Why did you want to write about the end of the universe?
There are many books about the beginning. I’ve read some of those books, and I’m fascinated by that question of where we come from. But there are very few books about the end. So I wanted to explore that other side. And I love the idea of studying the ultimate destruction of reality; I just think this is a cool thing to study.
The book goes through five theories about how it could have happened – and you suggest that the most likely of these is the heat death. Can you explain what that would mean?
The heat of death is … well, it’s the most depressing end possible in some ways. I find people sad when you talk about it. Our cosmos is currently expanding, and the way expansion plays out is that the spaces in between structures such as galaxies and galaxy clusters become larger. And in about 100 billion years, other galaxies will be so far away from us, and so fast away from us, that we can no longer see them.
That is the first stage. And with time, the universe becomes more and more empty. That you end up in this cold, dark, empty universe in which the only thing around there is a small amount of background radiation, which is actually the waste heat of the cosmos. That is why it is called the heat of death, because everything is so decayed that all that is left is this generated radiation and that is literally the waste heat of all the processes of the universe.
You’re right, that’s gloomy.
It’s true. I’ve given conversations where I have to talk about the impending death, and I’ve seen people hold their heads in their hands in the front row and just watch as they have lost all hope in the world. I did a few podcasts for young kids and once I declared the heat dead and the host of the podcast stopped me and she said, “I don’t think this is suitable for kids.” And I was, “Oh no!”
Your readings inspire a poem – No plan – by the Irish musician Hozier. Was that an unexpected development for you?
Oh, yes. I never thought I would fall into a pop song by name. It is not a pop song, but yes, that was not what I anticipated when I left to study physics in school. So we followed each other on Twitter for a while and I think that’s how he found my videos online. And when he sings that song on stage – people have sent me videos – he will sometimes give a two minute introduction about cosmology and actually explain the process of heat death and how it works. It’s so weird.
That he is then not worried about depressing his audience?
Now, if you are familiar with his lyrics, he writes about a lot of very, very tragic, heartbreaking things. That that sits a bit in his roller coaster, I would say.
Why do you think you’ve been so popular on Twitter?
It’s been slow: I’ve been on Twitter for about 10 years, and over time I discovered that it was actually a really good medium to talk about physics in a very concise and approachable way. And a few times I got a tweet viral, and that obviously does a lot. So I once had an exchange with a climate explorer that ends up on these lists of mansplainer smackdowns. I had not intended it to be so, but it got a lot of attention.
For those who did not see it, you tweet was a response to someone who suggested you learn and read some “real SCIENCE”: “I do not know, man, I already went and got a PhD in astrophysics. It seems that more than that at this point much would be. ”Didn’t JK Rowling write that it“ validated the existence of Twitter ”forever?
Yes, that was definitely a big impetus for my next: I think I went from 40,000 to 80,000 this week.
In the book you mention that Stephen Hawking was very influential. What was it about his work that resonated with you?
I found that stuff when I was, like, 10 years old and it resonated because it was all this mind-bending, weird stuff. The idea of black holes and space time and time travel, the big bang … these are all topics that make your brain hurt thinking about them. Then, later, I met him a lot because I was at Caltech [California Institute of Technology] as an undergrad and he would visit Caltech quite often. When I was at Cambridge then [University]To, I had an office with his so I would see him all the time. He came to a conversation I once gave that was wild.
Was that daunting?
Yes, because he heckled me! That technically he did not mean. I had only been at Cambridge for a month, and I was very nervous because I was giving this talk about primordial black holes, which is an idea that Stephen Hawking was one of the first originators. And when I started my conversation, I set up the title page and this mechanical voice says, “Thank you.” I thought maybe he was joking about how he came up with this idea and everyone laughed and I kept going. Then he would, through the conversation, occasionally just interview something like “Yes!” or “No!” Or “I do not think so.” And I would just look at him and he said nothing.
So at the end of the conversation I asked someone what happened. And it was an afternoon seminar and the way his voice synthesizer worked is that it had this little thing that looked down his cheek and he would be selected by clipping. And apparently it’s wrong when he eats. That his cheek moved and it chose random words from this Quick Select menu: thanks; Yes; No; maybe. No one warned me and I’m a grad student and I’m terrible. Here is my hero in public and he has heckling my seminar. That, “daunting” is a good word for that.
There was an eight-way bidding war between US publishers for your book. Does this show that there is a desire to read science books that address complex topics?
Yes, I find it amazing that people read physics books for the reading. I’m super glad we do. People are an interesting species, we want to understand things. And I love that about us.
What comes next? How do you follow the end of the universe?
That’s the problem, I’ve chosen the wrong topic. Am I writing a prequel? Restart?
• The End of Everything (Astrophysically Speaking) by Katie Mack is published by Allen Lane (£ 20). To order a copy go to guardianbookshop.com. Free UK p & p over £ 15
