Ideas53:59The end of everything: Katie Mack
Cosmologists aren’t sure when the universe will end, but they’re pretty confident it will. Since it had a beginning, it will have an end.
In about five billion years, the sun will scorch the earth until it’s crisp – unless humans finish the job before the sun gets a chance.
Katie Mack is a theoretical astrophysicist at the Perimeter Institute for Theoretical Physics in Waterloo, Ontario. She studies the possible fates of the universe.
In his book, The end of everything (astrophysically speaking)it explores the mind-blowing science behind different end-of-universe scenarios, and also questions the meaning of existence when nothing, not even the universe, will last forever.
Mack spoke with IDEAS host Nahlah Ayed on theories of the possible demise of universes.
Here is a short excerpt from their conversation:
You talk about Big Crunch, Heat Death and Vacuum Decay – they all sound so apocalyptic. But there is another possible apocalyptic fate of the universe you are writing about, called The Big Rip. Can you briefly explain what it is?
The Big Rip is one possibility where dark energy goes awry.
Dark energy is a mysterious substance that seems to be present throughout the universe, which is accelerating the expansion of the universe. And our best guess at the moment is that it’s a cosmological constant. It is something which is only a property of space.
But if it’s something that changes over time and gets more powerful over time, if the amount of dark energy and every little space builds up over time, then it’s not just pushing galaxies apart from others, it begins to expand the Inner galaxies. It begins to accumulate inside objects, inside related structures like galaxies and solar systems, but also solid objects like planets and stars.
And you can understand that the way it acts on the universe as a whole is that it quickly expands and expands and expands to the point where you can calculate a date based on certain characteristics of the theory . You can calculate a time in the future at which the entire universe would be torn apart. It’s the Big Rip.
Although unlikely based on our understanding of how dark energy might work, or our understanding of the possibility of what dark energy might do, it is not ruled out by the data. It’s about understanding dark energy and we don’t understand dark energy. We have some ideas about dark energy, but we don’t know what it is fundamentally.
I wonder what the effect is of working in – and hearing these kinds of end-of-the-universe possibilities. I mean, as you say, some of these patterns cause the universe to actually last trillions of extra years. It looks like eternity, but it’s not really eternity. How much does it bother you or you and other scientists and people in general to think that the universe just won’t last forever?
I’ve been around and asked my colleagues about it as part of the book. I asked them about the science of these different possibilities and the observations it will take to place limits and that sort of thing. And I made sure in every interview to ask: how does the end of the universe make you feel? What does this mean for you personally?
There was a wide range of responses. Some people said it’s okay, we should be temporary. It’s part of life. Some people said it was a really disturbing idea – and some of the people who said it was a really disturbing idea were actively working on possibilities that have a continuation of a sort of cyclical universe.
![](https://oponame.com/wp-content/uploads/2022/10/Cosmologist-Katie-Mack-explores-scenarios-for-the-end-of-the.jpg)
A lot of people find it very disturbing, the idea that we don’t last forever, even though by eternity we’re talking about something so far in the future that we can’t conceive of it. There is still something visceral about the idea that all of this will be destroyed. And everything we’ve seen, everything we’ve been through will end and we won’t have a legacy in the future. I think it’s more disturbing than other aspects because if I think about my own death, I think I’m going to die. Everyone dies.
But I would have done something. I will have contributed to my field. I wrote a book. I might have made someone’s life better, maybe — and other people might say, “I built this amazing building,” or “I had kids who did amazing things,” etc. .
People have a legacy that is important to them when they think they are nearing the end of their life. And if the universe is going to end, then none of us have any legacy at all… But at some point, there will be a time when all human endeavors will have been erased. And I think that’s specifically very disturbing.
Are you saying this is an observation or is this also your feeling?
This is also my feeling. I don’t like the idea. I don’t want the universe to end – I like it here. So yes, that confronts me too. One of the things I talk about in the book is trying to fight that myself, with the idea that we don’t last forever and nothing we do lasts forever.
And what I took away from it is that you have to find a kind of meaning in the universe that is not based on the future. You have to create meaning yourself, have a way to make the universe matter and find purpose without relying on, you know, “Oh, it’ll be alright in the end” because maybe it’s not the case.
* Questions and answers edited for clarity and length. This episode was produced by Chris Wodskou.
#Cosmologist #Katie #Mack #explores #scenarios #universe #Radio #Canada