Lawrence Krauss Interview transcript – Prominent People Project
This is a transcript of the interview I conducted recently with Professor Lawrence Krauss. Listen to the audio file, and see the original post here.
MSP: Firstly I just wanted to say “Welcome to Australia”, what do we owe the privilege of having you in the country?
LK: Ha ha, well, there’s two reasons. One , I’m working with several people at both Mount Stromlo and up in Melbourne, but also my, um, my significant other lives in Australia, so I tend to… I’m doing a lot of commuting.
MSP: And what are you working on at the moment that brings you here, apart from your significant other?
LK: Yeah, well, um, this week I was working on some on some science having to do with processes involved with dark matter with some particle physicists at Melbourne, and I gave a lecture on the future of the universe to the physics department as well.
MSP: Oh great! And how’d that go?
LK: It was a lot of fun! No one died, it’s one of my ways of measuring… No it was a lot of fun, it’s for the students and faculty, and actually I talked about the limits on cosmology that are happening. We’ve discovered so many things about the universe in the last decade or two that we’ve come to the threshold of questions that may or may not be answerable. So I talked about that. I’ve done some work on that, and I also finished, while I was here, a part of a children’s book on science that my friend Lucy Hawking is putting together, Stephen Hawking’s daughter. So I wrote a bit on the future of the universe for her. And I’m working on developing a curriculum for Origins back at my university.
MSP: So, um, the field of astrophysics seems to be like the ultimate of science, it seems, because it deals with everything. How would you say this differs from, say, normal physics, or you know, just “physics”? And what does “theoretical astrophysics” mean to the average person?
LK: Ha ha, okay well, I think the average person doesn’t know what theoretical astrophysics is. I think one of the reasons why I try and spend a lot of my time talking about it. I think that the interesting thing about thinking about the universe is that we, that makes it a little bit different from the other areas of science is that we only have one universe, the universe we live in, and therefore, there a properties of it that we want to understand but we have a sample of one. So when it comes to trying to understand exactly what may be fundamental or not, we have to recognise that we have limited information, and we always will, and we have to try and infer, based on that, the way the universe works. And it is really remarkable that we have been able to understand the universe back to the earliest moments moments of the big bang, fractions of a second after the big bang, and that we can speculate with some confidence about the future of the universe. And that we can measure such things as the age of the universe to an accuracy of a few percent now. It’s just almost unbelievable.
MSP: Yeah that’s fantastic. And what do you think was the most momentous moment in astrophysics that brought that about? Was it something like the Hubble Deep-Field photographs, or…?
LK: Um, well I think that, well, Hubble certainly changed a lot of things. The biggest change in our picture of the universe, that really changed everything, was the discovery of what’s called “dark energy”, the fact that the dominant energy in the universe resides in empty space. Totally unexpected for the most part, although I have to say that colleague of mine and I had argued a few years before it was discovered that it was probably there. Although I’m not sure we really believed it, we did write a paper saying it was, and we were right. But it’s still so inexplicable that empty space weighs something. That we, um… It’s changed everything about our picture of the present and the future and our understanding of the nature of the universe, so it’s an exciting time.
MSP: Hmm, so, um, I’ve read a little bit about dark matter and dark energy, and all that. I know that people have a tendency to think that they’re the same thing. Like people will go “dark matter, dark energy”, even though we know that they’re not. How would you describe, say, dark matter as opposed to dark energy?
LK: Well dark matter is much easier to understand, it’s material that doesn’t shine, it falls like normal matter, it’s gravitationally attracted, it just doesn’t shine. It’s made of some new kind of elementary particle which is incredibly exotic, but at least understandable. There’s a lot of ways you could have new types of elementary particles that would hide, and that wouldn’t interact with light. But dark energy is totally inexplicable, because it means an empty space, when there’s nothing there, there’s an energy there, and how it comes about, we just don’t have the slightest idea. It’s fascinating, and it’s also gravitationally repulsive. It’s like “anti-gravity”. And so it’s really the most exciting thing you could imagine.
MSP: So does that mean that dark matter has a gravitational pull, but dark energy has the opposite effect, and that’s sort of what holds the universe together?
LK: Well, no, in fact it’s doing the opposite of holding the universe together, it’s blowing it apart. The universe is expanding at a faster rate every day. And it means everything that we see now will eventually be moving away from us faster than the speed of light.
MSP: That’s a really cool concept. I know I’ve seen you speak in the past and say that one day, or I’ve heard you speak in the past, saying that one day, astrophysicists say in several thousand years, or several hundred thousand years or whatever, will be looking up at the sky and not seeing anything but our own galaxy, and have no proof that that ever existed. That’s a pretty amazing idea in itself isn’t it.
LK: Well it is, and that’s why I’ve written about it. It’s kind of amazing to think that in the far future people’s picture of the universe will be dramatically different than what it is, and they’ll come up with the wrong picture of the universe even though they’ll develop all the kinds of physics we have, general relativity and quantum mechanics, and they’ll build telescopes… But they’ll develop the completely wrong picture because they won’t have access to most of the universe. That should cause us some humility now, because we, once again it points out the limits of our ability to measure things, and therefore even though we put together this amazingly interesting and consistent picture of the universe, it doesn’t have to be right, it may be incomplete because there may be things that we haven’t seen that we cannot see.
MSP: That was actually going to be my next question. Is it possible that our understanding of the universe, given the time that we’re in, is incomplete because of just this same phenomenon?
LK: Well that’s the interesting thing, it certainly could be, and we don’t know, but it’s certainly true that we’re limited to what we can measure, and therefore we should always have some kind of skepticism, well we should always have skepticism in science, but also some kind of humility about knowing everything.
MSP: Cool… I’ll move on to a slightly different topic now. I had someone who asked if you could explain what the “nothing” before the big bang was? It’s one of those concepts that, nothing, you know, because we depend upon interactions with objects and things, the idea of nothing is beyond comprehension. What does the “nothing” before the big bang actually mean?
LK: Well it could be many things, it could just be that there was empty space, space existed but it was completely empty, or it could be that space itself didn’t exist, and it came into existence with the big bang. That’s hard for people to picture, but space is… general relativity tells us that space itself, the features of space depend on the nature of matter. And it’s dynamical, and it’s certainly possible that the laws of quantum mechanics caused literally space to suddenly come into being. And so there could have been nothing, there could have even been… And people might say “well and then there are laws of physics of course and those existed”, but it coudl be that even the laws of physics came into existence at the same time as space did. And what we know is that when we look at the universe, the total energy of the universe is zero, precisely consistent with a universe that came from nothing, and it’s kind of remarkable, it didn’t have to be that way.
LK: I should tell you that I’m writing… My new book, I’m writing a book on that lecture I gave which has become so popular and it’ll be done in February, and it’ll come out some time the end of next year, or the year after. And so, I’m refining the ideas of how something could come from nothing.
MSP: Fantastic, that’s great, I’m sure we’ll be looking forward to reading next year. Hopefully it gets a reasonable distribution so I can track it down easily enough.
MSP: That actually draws me on to another question I had, I recently read an articel that stated Sir Roger Penrose suggested there was evidence for the possibility of a cyclical universe, one that goes from one big bang to another, to another… Have you heard about this, is this something that you take seriously?
LK: No… There’s no evidence for that, and I don’t know why people are quoted as saying that. There’s no evidence for that whatsoever, and some people like the idea because it’s kind of symmetric and people don’t like a universe that doesn’t have a… that has no end, but has a beginning. But there’s no evidence that we come form a cyclic universe that I know of.
MSP: Okay, now I wanted to ask you about education, because I’m a teacher myself, and think that education’s really really important. I notice, well it’s hard not to notice, but in the US there seems to be a real growing trend of distrust in the sciences, in discoveries, in methods et cetera.
MSP: And it sort of seems to be falling over here in Australia as well. What would you say is the biggest reason for this, and is it something that we really have to be worried about? Or do you think it might just be a passing trend?
LK: Well, I think it’s much worse, the problem is much more severe in the United States. And, I think, it’s hard to know if it’s a passing trend, I certainly hope so. But it is dangerous, because we’re at a threshold of times where we really need to accept the world the way it is. There are urgent problems that need to be faced by humanity. And this growing distrust of empirical reality or the ability to spout nonsense with impunity is of great concern, and I think we should all be wary about it, and I think we should be… we should all become evangelists for science, because it needs it. I mean, ans that means not just people like me, you know, writing in newspapers or being on TV or writing books, but everybody, you in your classroom, people who go to church talking to people in their church, to just talk about and understand the problems we face, and the nature of reality, and not accept the nonsense, the stupidity, the ignorance, that one would have hope would have been dissipated a long time ago.
MSP: Yeah… I think that in America it might be more due to the extreme religiosity of the people… I don’t know if we have that same thing here.
LK: But, there’s also power and money that… Global warming, climate change is an example of, the denial of that, of just the real science, because you can do it, and you can advertise, and you can spend a lot of money. It’s kind of sad that public policy is determined more by power and religion and ideology than it is by reality.
MSP: Yeah it’s very sad. And we see it more and more in news stories about the US. Don’t worry we’re sort of… we’re behind you guys, well at least me and my friends are.
LK: Well I know, and it’s true, but some people tell me it’s just an American problem, but what I tell them is that The United States exports everything, both good and bad, so just wait.
MSP: (laughs) yeah… I did want to ask you about Star Trek, and, because I saw a talk with you and Richard Dawkins, you know, the one that’s on his website…
MSP: … and you were talking about how you like to go to wherer the people are, and that’s why you wrote the Star Trek book, yo try and get people, like the general public interested in what you were talking about.
MSP: My question to you would be… It’s sort of tied in with something Michio Kaku said about The Kardashev Scale and the idea that the humans in Star Trek are a Type Two civilization, and that The Borg, which we see as a very unsavoury outcome for humanity, is a Type Three civilization. Do you think that The Borg is the only way that someone could, or a civilization could become a Type Three? Or do you think that there would be a more palatable alternative for humanity that doesn’t mean the hive-mentality and all that sort of thing? Just off the top of your head. (laughs)
LK: Oh that’s so speculative… ah… I think… Humans do not have a hive-mentality, and it’s hard to se that we would… that that aspect of humanity would change. We’ve evolved differently, however we will, I think, over time, once our artificial intelligence and computational skills and abilities progress, I think we will adopt… what we mean by humans will change and we sill adopt various aspects of what you now call computers, and so what humans will be in the future, or what our consciousness will be in the future is hard to say. But I would be amazed if it remained in a purely biological form. But um… And we may work better together, and it’s interesting to me that it’s always viewed of that as being bad. And I suspect that that we find as we can adapt to new ways of improving our consciousness and our abilities that it could easily be good too, and we could… You know I think, it’s hard to say, but we might just go in the completely opposite direction, where we don;t need to assimilate anything, we don’t need to expand, we have… we find that we have everything we need, and we turn inward, and that’s equally possible.
MSP: I’ve thought that myself. That’s great. Hey have you got time for on last short question?
LK: Yeah sure…
MSP: Okay um… What would you say as an advocate of science and the learning of science, what would you say to someone who ia up-and-coming and thinking of a career in science to convince them to go into that field?
LK: Well you know, first of all it’s an incredibly exciting time in so many areas of science. And that the reason to do science is not to save the world, by the way, it’s to have fun. And the reason people I know who do science, do science because they enjoy it. So if you enjoy it, what can better than enjoying something, and at the same time going boldly where no one has gone before? It’s a very fortunate opportunity. And that as long as you enjoy it, it’s worth doing, and if you;re good at it, then it’s worth doing as well. And so I tell young people who are interested in science to just go ahead and try it. And don’t worry about, it you’re young. Don’t worry about jobs and don’t worry about other things. It’s the one time in life you have to follow your heart and your dreams and go ahead and just see what happens. And it’s a good preparation for everything else, it’s not a waste of time. The problem solving methods, the techniques, will serve you well no matter what you do.
MSP: Fantastic. I guess we’ll leave it there, thanks to you, so much, Professor Lawrence Krauss, for giving up your time this morning.
LK: Thanks for your patience in finally a hold of me.
MSP: That’s fine, I would have like to have actually met you in person and got you to sign your book for me but…
LK: Well I’ll be back in Melbourne in August for an extended period.
MSP: Oh fantastic, and will you be doing any talks…?
LK: Yeah yeah I have some fancy fellowship at the university there called the (unknown garbled) fellowship which requires me to give two or three public lectures so I’ll be doing that.
MSP: Fantastic, well we’ll keep a lookout for that and enjoy the rest of your time in Australia.
LK: And enjoy my new book when it comes out in March, I think it will come out here in March too.
MSP: I’ll make sure I publicise that for you.
LK: Okay, okay, thanks! Bye!
MSP: Thank you!