Where we came from, and where we’re going

Robyn Williams: Hello again, Robyn Williams with, today, the science of friendship.

Brian Greene: There's so much untapped potential out there in the world, and it's so gratifying to hear a story where somebody allows that potential to flourish. I mean, what is life but an opportunity to actualise your potential. And if somebody can be the catalyst allowing you to actualise that potential, how beautiful is that?

Robyn Williams: Brian Greene, a Professor of Physics at Columbia University in New York, and he was here in Australia just now as the founder of the World Festival of Science in Brisbane, in March. A huge attendance, with many from ABC science there, as you may already have heard.

But in this Science Show there'll be lots on friendship as a real biological entity. Yes, there's aggression, plenty of wars, but most of us, most of the time, get on. So, what's the secret? Back to Brian Greene, and Until the End of Time.

Your book on time, how did it go?

Brian Greene: Really well, it did a number of weeks on the New York Times bestseller list, which is always a great thing. But it came out right when the pandemic was hitting. So I was on my book tour, and it was as if every city I'd just left, there was an outbreak. So I was beginning to wonder if I had something to do with the spread, but I'm sure it was just all coincidental. Yeah, you know, unfortunately the book tour got cut short, not by a week or two but cut short by years. It's a funny thing, when you're out there needing to promote something and the world just turns upside down. It's the least of the world's troubles, but it was a little disappointing for me because I love talking about it, I love getting the word out.

Robyn Williams: And the feature of it, as with the World Science Festival, which incorporates art in various ways, you incorporate almost the whole of life when you're dealing with time. How dare you do that? It's extraordinary.

Brian Greene: Yeah, my goal was really to show how we humans came to be, both from the point of view of the physics and the cosmology of it—how did the Sun form, how do planets form, how does life emerge—but then the real question I wanted to explore was, once life emerges and once consciousness, once self-awareness emerges, what do these self-aware collection of atoms do? And what we try to do is we try to find coherence, and we do it in many ways. So it brings in storytelling, it brings in mythmaking, it brings in the creation of art, it brings in theology, imagining that there's something beyond the physical, because, look, we're a lonely species coping with our own mortality. And it's an incredible invention to imagine that there's something beyond the life that we actually lead. So you're right, in the approach I took, trying to, in some sense, canvas the universe from the beginning to the end, a big part of what matters is human experience. And human experience brings in everything that we are familiar with, in one way or another.

Robyn Williams: One thing you deal with is the question of entropy. It seems to go against the laws of physics that you will have coherence, even the building of planets, let alone of Brian. And okay, we do die, as you said. But nonetheless, keeping things together, there have been lots of theories of this. And we've talked to Paul Davies who wrote a book involving this and referred to some of the ideas about how there's a devil in the machine somehow, there's an entity that keeps it going, which is of course suggesting almost that there's something that is spiritual, who knows? How do you yourself in the book answer that question about why we don't just fall apart straight away, but live for 100 years?

Brian Greene: So I take an approach that I like to call the entropic two-step. It is not a technical term, but it to me evokes the essential idea which is this; the second law of thermodynamics, you're absolutely right, speaks to the increase in entropy, the increase in disorder, which would suggest that everything should just fall apart. In fact, it even suggested there shouldn't be any order at all, like where would order come from? And the answer is that order can form in one region of space, so long as in the process the creation of that order generates enough disorder to counterbalance it. So, in aggregate, the amount of disorder goes up but not at the same location. At one location you can have an orderly structure like a planet or a star or a person come into existence, so long as the process itself generates enough heat and light and waste that spreads outward to the wider world. So you get a lot of disorder in the surrounding environment, but you get a nice beautiful pocket of order that forms in the wake of this process. And that's really how stars and planets form, it's really how we form. Now, ultimately, entropy does win. If you wait long enough, even that pocket of order will disintegrate, it will fall apart. When will the Sun and the Earth fall apart? But when it comes to life forms, we're well familiar, because the timescales are the timescales that we experience. So we can hold together, you know, for roughly 100 years, but after that we disintegrate too.

Robyn Williams: And when it comes to the galaxy, and indeed our own universe, when we come to the end of that, when that sort of runs out and there's just nothing but space with very little in it, what you do then is lock in another universe from somewhere else…

Brian Greene: Conceivably.

Robyn Williams: Who knows.

Brian Greene: Yes, we don't know. It could be that in roughly 10¹⁰⁰ years, which is an incredible timescale, right? We're now at about 10¹⁰ years, like 10 billion, 13 billion years since the Big Bang. If you go to 10¹⁰⁰ years, then even black holes, which will be the one remaining macroscopic astrophysical object, even they fall apart. Stephen Hawking taught us back in the 1970s that black holes themselves can slowly emit radiation, something can get out of a black hole. This is what Stephen Hawking is famous for. And so black holes emit radiation, and they fall apart in roughly, if they're a large enough black hole, in 10¹⁰⁰ years. So at that point we have a universe much as you describe it; it's space, with particles wafting through the void, very dilute, there's very little out there. And you might think, well, that is just it, it'll just stay like that forever, but the weirdness of quantum mechanics is that if there's a slight chance for anything to happen, if you wait long enough, it will happen, which means that two particles can somehow find each other in the void and stick together, and a third if you wait long enough, and a fourth, and then over time, you can start to have agglomerations of particles reform and they could give rise to stars and planets and people and so, in principle, this could in some sense start to happen again, if you wait incredibly long timescales.

Robyn Williams: Okay, I've waited enormous lengths of time, except that there's no time, but you understand what I mean, and there's nothing. And this is what I tried to ask Alan Guth. You know who Alan Guth is?

Brian Greene: Sure, of course.

Robyn Williams: And here we have nothing, and somehow out of nothing there came, boing, something. How can you get something coming out of absolutely nothing…it's not just a vacuum with a bit of energy floating around, it's got nichts, gar nichts, verstehe?

Brian Greene: I do.

Robyn Williams: So how do you get that initial start?

Brian Greene: Absolutely no idea. And anybody who says anything else is either speculating beyond speculation or is not really being forthcoming. The bottom line is Godfried Leibniz asked that question—why is there something rather than nothing—many hundreds of years ago, and we still don't have an answer to it. It could have been, logically speaking, that there was truly nothing and, as you emphasise, by 'nothing' I don't mean empty space or space with a little bit of something that's dispersed so it's very close to nothing, I mean truly nothing, no space, no time, no energy, no laws of generativity, no laws of quantum…no mathematics, no abstract anything, no platonic place where all these shapes are existing in some abstract realm, nothing. Why isn't it like that? We don't know.

Now, there is one possibility which I'll just throw out there. It could be that if you allow me to bring quantum physics into our discussion…again, you can say why quantum physics, where does it come from? I don't know. But if we just bring in quantum physics, quantum physics may tell us that nothingness could be an unstable state, which means if you had nothingness and you wait long enough, it has to fall apart into a something and an anti-something. They overall cancel each other out. But you can have a world and an anti-world, a universe and an anti-universe, and perhaps we live in the universe, and perhaps there's some anti-realm that's out there. And collectively we have nothing, like five plus negative five is zero, but you can still have a five and a negative five. Maybe we have the universe and a negative universe, and perhaps that gives us some insight into how something can emerge from nothing.

Robyn Williams: Wow! My final technical question, just to keep us up to date, I haven't heard very much about strings and string theory lately. Are they still current?

Brian Greene: Absolutely. String theory, as you know, was developed as far back as the late-1960s. It is an approach to deal with a deep problem that we physicists have faced, which is that the laws of the large, Einstein's general theory of relativity, it's the understanding of gravity that Einstein bequeathed to us way back from the early part of the 20th century, that theory seems to be deeply incompatible with another theory, the theory of the small things, called quantum mechanics. And so we've been struggling for a very long time to find some way of ameliorating the hostility between the laws of the big and the laws of the small, and string theory, which emerged in the 1960s, is our best approach for doing that.

But developing string theory to a point where we can test it, that's extraordinarily difficult. And we've not been able to bridge the gap between the mathematics of string theory, which has been developed to extraordinarily miraculous places in the last two decades, it's amazing where the mathematics has gone, we've gained insights mathematically into black holes, into the fabric of space and time, the developments are absolutely mind blowing, I never thought we would get this far in my lifetime. But the part that we've not been able to make headway on is; is it right? Does it make predictions about the world that we can go out and test and confirm that the theory is correct? We have made basically no progress on that question at all. So as a purely mathematical endeavour, extraordinary progress. As an experimental science, very little progress.

Robyn Williams: Interesting. Now, I'd like to catch up on a few bits of gossip about especially yourself. Is it true that with some member of the family you walked up one of the streets (you were very young) to Columbia University and said, 'I want to do maths,' and they let you in?

Brian Greene: Yeah, that is true. What happened was I went to public school in New York City. And again, I'm not sure if your language mirrors that of…

Robyn Williams: State school.

Brian Greene: Yes, it's the free state school that everybody went to. And I was pretty good in math, and so by seventh grade I'd pretty much exhausted what the school could offer. And there was a wonderful teacher there, who said, 'Look, take this letter,' which he'd written, I didn't know what the letter said, he said, 'Go up to Columbia University, which is just a couple miles up the road, and just give this letter to somebody and maybe it'll yield something.' I later on realised that letter said, hey, it's a smart kid, we can't teach them anything else, can you take him on?

So I went up there with my sister, my older sister, so I was 12 or something, she was 15. And we just started to knock on doors, random doors at Columbia University, Computer Science Department, Physics Department, Math Department. And the Math Department, I gave the letter to somebody, and unlike the previous ones where they took the letter and just sort of didn't know what to do with it just gave the back, this one individual read it and said, 'Sure, I'd love to teach you.' And the letter made clear that we couldn't pay anything, we didn't have any money. And, for free, this amazing graduate student in the Math Department at Columbia University met with me three days a week over the summers and weekly during the academic year, and took me on these mathematical journeys that I would never have been able to experience without a guide who was dedicated to taking me to these places. And it was just an amazing thing.

Robyn Williams: Could it happen now?

Brian Greene: In principle, it could.

Robyn Williams: We need the mathematicians desperately.

Brian Greene: Yeah. But it's a funny thing where the world has gone now. I mean, now people are so wary of anybody who wants to do good. There's always a thought that perhaps there's some ulterior motive or some kind of predator. I mean, there's just so many constraints on just trying to be a good person. And look, I understand there are real problems in the world, but I think it's much more difficult to just be a straightforward human being perhaps in a way that was easier in decades past.

Robyn Williams: Secondly, I was cheeky enough to set up Top 100 Scientists in Australia, and very, very quickly when that was published everyone said, 'Oh, what about him? What about her?' Obviously we'll have to have an emeritus list…if you're dead and you've got a Nobel Prize. We've got the youngest person ever to get a scientific Nobel Prize, that's Lawrence Bragg, who was 22. But he was fighting in the war and he didn't actually get it physically until a priest came along in the trenches and said, 'You should have this.'

Brian Greene: Is that right? I don't know this story.

Robyn Williams: It's incredible. And he of course was one of the amazing people at the Cavendish Laboratory and employed I don't know how many other people. Do you think it's important that the general public knows who the scientists are, something about them. You know, this seems to me…you are the person who helped invent the World Science Festival, and we now know why because we've been listening to you, with your enthusiasm, talking about time and physics and everything. So do you think it's important we know that?

Brian Greene: Yeah, I think it's really important because for many people science is this abstract collection of ideas that perhaps caused them some distress when they were in school, because in school we put pressure on students to be able to perform on assessments. And for some people that's fine. For other people it's deeply anxiety provoking, and ultimately kind of makes them feel bad. Science is not about the exam. Science is not just about the idea. Science is about the people who are trying to push the boundary of understanding so that we can just understand ourselves and understand the world and understand where we came from, and where we are going, and what are the opportunities we have for understanding the world better. And if you can put that all in deeply human terms, where science becomes a human drama of exploration, a human drama of trying to figure things out, it becomes a narrative that's deeply compelling. It's a story that you want to know more about because it's telling you about the very environment within which we all operate. And so yes, if you can have people become more aware of the human beings that are driving this human quest, I think that's a vital thing to do.

Robyn Williams: Indeed. Well, one of the examples I gave very briefly which inspired this was what did Henry Sutton do in Ballarat in 1885? And people look at me very strangely. The answer was he invented television. Why don't we know this? Well, it turns out he was one of the greatest inventors in human history, and you don't know this because he did it for the public good, he was not interested in patenting, and so many scientists are of the same mindset; we do this because it is wonderful to improve the world that we know. And most of the people we've got in this list are like that. But we think of scientists as distant, remote and on some sort of obsessive thing.

Brian Greene: Well, we're a deeply asocial species, right?

Robyn Williams: Are you? Why did you invent the World Science Festival?

Brian Greene: For the very reason that you're saying, to combat that perspective. Our view was if people could actually interact with the scientists themselves, as opposed to those who were interpreting the scientists, then it would bridge the gap between the general person and those who are pushing the frontiers of understanding, and how exciting and wonderful is that? I mean, how exciting for a kid to meet the Nobel laureate, to meet the Alan Guth that you made reference to before, and really feel the excitement of a human being who changed our understanding of the world, who changed our understanding of the beginning of time, or how the universe expanded. There's nothing more exciting for a kid than that, and we want to have those kinds of experiences.

Robyn Williams: Well, the world, the news is so full of people doing terrible things, there are accidents, that are murders, they're all sorts of…and you'd think this is hell on Earth. However, you've given stories about being taught in Columbia. I'll give you one story, and I'd like your comment, about the president of the Australian Academy of Science, Professor Jagadeesh, who came from a very small village in India, terribly, terribly poor. He did well at school, like you did. But the high school was 13 miles, as he put it, far away, and so he thought, well, we'll have to give up. And the family was terribly upset.

The next thing that happened was the teacher in the high school, which was so far away with no public transport, you couldn't get there, came to the village and said, 'I am the teacher in the school, and we would like your boy to come and live with us, because he's obviously got wonderful talent, and it would be an exciting thing.' And that's how the president of the Academy of Science, which is celebrating its 70th anniversary, went to the high school, went to the university, went to America, and didn't exactly get the Nobel Prize for LEDs, but his colleagues did, but that was his field and he's a nano scientist.

Brian Greene: Yeah, it's a beautiful story because there's so much untapped potential out there in the world, and it's so gratifying to hear a story where somebody allows that potential to flourish. What is life but an opportunity to actualise your potential? And if somebody can be the catalyst allowing you to actualise that potential, how beautiful is that?

Robyn Williams: Professor Brian Greene, founder of the World Science Festival, and Professor of Physics at Columbia University in New York. His book, Until the End of Time.

[Music – Opening of Stabat Mater by Giovanni Pergolesi]