Global Courant 2023-04-19 01:22:52
The current23:13Cosmologist Thomas Hertog on Stephen Hawking and the origin of the universe
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After completing his doctorate, Thomas Hertog – a close associate of Stephen Hawking – went on vacation along the Silk Roads.
Hertog was trapped on a bridge in northern Afghanistan when he received an email from Hawking asking him to give up his vacation and come back to work for him.
“This was when he realized that A Brief History of Time had been written from the wrong perspective,” Hertog said.
Duke did as he was asked. The border guard there in Afghanistan turned out to be a fan of Hawking, and let Hertog pass after seeing the physicist’s email.
Hawking’s book, A Brief History of Time, reshaped the scientific understanding of the universe by positioning the Big Bang as the beginning of time itself. This realization that he had been wrong about the origin story prompted both Hawking and Hertog to work on a new model for the universe.
In his book On the Origin of Time: Stephen Hawking’s Final Theory, Hertog explains how he and Hawking’s thinking changed. Hertog, a theoretical physicist and professor at the University of London, spoke to Matt Galloway, presenter of The Current, about Hawking’s amazing thinking and their collaboration. Here’s part of their conversation.
Hertog is a theoretical physicist and professor at the University of London. (Gert Verbelen)
You say Hawking had some magic. What do you mean?
When I met him, (it was) 1998. A Brief History of Time had already been published. He was already famous, but he could no longer write equations. By then, he had developed this amazing ability to do research in theoretical physics…almost in his head. He had come up with this visual way of manipulating shapes and forms and universes and black holes so that he could kind of develop his intuition without having to do these actual calculations.
And this drove many of us crazy precisely because we were doing these calculations and he was figuring it out in his head. (But) I loved it from the very first second I met him in ’98. I just loved it.
You describe the practical elements of (working with Hawking) when communication became more and more difficult for him, but when you got past that it must have been exciting to work with him.
We have worked together for 20 years. We came to great new insights when he used his computer voice in the late 1990s and early 2000s. All in all, communication went fairly smoothly.
But that communication slowed dramatically for six, seven years before he died. But… by that time it turned out that we had developed some kind of common language and we started collaborating with a lot of non-verbal communication.
And so, towards the end of his life, I was able to fire questions at him (and) detect varying degrees of no and varying degrees of yes through his facial expressions. And so this became a very strong bond, because in a way; it’s almost like we’ve developed a kind of intimacy around cosmology.
A Brief History of Time is quite mind blowing in what it explains. Explain the essence of that theory of the universe.
In the early 1980s, Stephen came up with a scientific model that he interpreted as the creation of our universe – the creation of space, time and matter from what he called nothing. And of course everyone asks, well, what does it mean, nothing? What came before the Big Bang?
But this in itself was a monumental achievement, because until then it was thought that the big bang, the actual beginning of time, … was not solvable within science. And here comes Hawking with a scientific model that includes the big bang.
But unfortunately his model created an empty universe – a universe without stars and galaxies and life, and therefore not a very useful universe. And that got him thinking about a much better theory, which eventually led to a completely different view.
What was your reaction when he said he changed his mind?
I sort of expected it, because such fundamental changes in our thinking about the universe, it’s this typical story of paradigm shifts in science. The model you’re working with doesn’t work and at some point one of the key assumptions just has to go away.
We got into such a paradigm crisis and then we broke up. And it sort of crystallized in my mind – and apparently it crystallized very much in his mind – that (the) assumption of A Brief History of Time had to go.
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One of the things he says to you is, “It’s time to stop playing God.” What changed for him?
We’ve built physics from what Stephen calls a God’s-eye perspective over many, many generations and centuries. This is really the success of science – that we’ve been able to study the world in a sort of objective way, as if we’re outside the system we’re trying to understand.
If you try to understand the habitability of our universe, the fact that we exist in the universe, then it is clearly wrong to look at it from the outside. And that’s what Stephen did in A Brief History of Time, which is why he told me (it’s) written from the wrong perspective.
It takes an incredible amount of humility for someone like Stephen Hawking to say he had the wrong perspective, doesn’t it?
Yes, I’m sure. I admire him for that. Stephen, of course, had an ego, but his passion for understanding was greater.
What are the implications of (this new theory), do you think?
There are many. We are always told that the laws of physics are some kind of eternal truth. We arrive at a fundamental evolutionary understanding of those laws. So not a real foundation, in a way similar to the laws of biology, which came together with different layers of life. So those are the big implications.
Hertog’s new book is called The Origin of Time: Stephen Hawking’s Final Theory. (Submitted by Thomas Hertog)
What does it say about the role of a higher power in helping to explain why we are here?
We have always viewed the laws of physics as immutable, eternal truths. And now I say they are the result of an evolution, involving many channels and some necessity and a random process. This model allows you to reveal the interconnectedness not only between the different types of life, but between the physical levels of the universe.
We also say, precisely because we have made that evolutionary character so central, that the idea that we would find an absolute answer for a definitive theory in physics may have been misguided. Perhaps there are limits to science. Perhaps there is a certain finiteness associated with that. And that, of course, leaves room for some mystery.
You end the book by saying that Hawking was the freest man you ever knew. What do you mean?
He was intellectually free. He was so willing to let go of dogmas and reimagine the world and rethink the foundations of physics. I’ve never met anyone like him. This feeling of freedom, despite these terribly difficult circumstances… it was very special.
Q&A edited for length and clarity.
