The mathematician and author Steven Strogatz and the astrophysicist and author Janna Levin interview leading researchers about the great scientific and mathematical questions of our time.
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Event horizon. They didn't quite have a idea. The idea came out of Einstein and the general theory of relativity that if you had such a heavy object, there would be a surface around it where anything that's inside that will fall in the the singularity, this surface of last escape, where if you're inside it, you're doing If you're outside it, you'll have a chance. And that's called the horizon of the black hole. Is there anything at the horizon? That is the whole question. Somebody observing the black hole from the outside doing measurements, doing helicopter observations, and also being allowed to lower probes down to the black hole. Let's say on a fishing wire, they used to be a fisherman. You will lower your worm down to the surface of the black hole. What would happen is you would see the surface of the black hole in the event horizon as being very, very hot. The poor worm would be, roasted very quickly. So somebody on the outside would reckon that, yes, there is something at the horizon, and whatever it is, is extremely hot. So hot that let's just put it this way. You wouldn't want to be there. This is what you would say was Hawking's result that it would be hot. Yes. That's correct. Hawking and to some extent, a predecessor of Hawking Backenstein. Hawking's results were clearer. They were more precise. And Hawking would have agreed completely with me that that worm will get fried at the horizon long before you get to the singularity. On the other hand, if you just cut the string of your, fishing line and let the worm fall through the horizon The story goes that the horizon would be another event for the world. The worm would just fly through observing nothing special at the horizon. Yes. Hawking would agree with that. The problem with it is
Way. This again relates to what we've learned from physical systems, specifically physical systems close to a phase transition. So a a system that's close to a transition between different states such as between, a solid and a liquid, you know, if you're freezing water and it suddenly transitions into a solid, the collective behavior of that system is quite remarkable near that transition point, this bifurcation, which of course is your own area of study. And this is something that we now know. We now have very strong evidence that natural selection pushes systems close to these bifurcation points because of the collective properties, the remarkable collective properties that are exhibited. When we first measured these properties, it seemed like the individuals were defying the laws of physics. The information was percolating so quickly. And in the sort of early 1900s, Edmond Sallis, who was a confirmed Darwinian, but, you know, also sort of captivated by the fascination with telepathy in the Victorian era. He has assumed there must be thought transference, he described it, or telepathy between birds that allow them to communicate so quickly. And of course people, you know, think, well, that's ridiculous. Of course, there can't be telepathy. But in actual fact, and this is maybe a little controversial, but in actual fact, I think we still don't have a good grasp of the sensory modalities and the way in which this information percolates so exquisitely rapidly across the system. I'm not suggesting this telepathy, of course, but I'm suggesting that by tuning a system, by tuning a collective system close to this critical point, close to this bifurcation point, it could give rise to remarkable collective properties that, to an observer, look fantastical, to an observer, look bizarre. Because the physics in these regimes is bizarre, is fantastical, is amazing even though it's understandable.
Scientific discovery. So at the Center For Quantum Precision Measurement, yes, we'll be developing technology but with an eye on better measurement strategies that exploit properties like quantum entanglement, which will allow us to measure things with, greater precision and less invasiveness. Everybody wants to measure things better and quantum strategies can help us to do measurements that wouldn't otherwise be possible. That's really the intellectual theme of that center. Yeah. And everyone wants to control information better, faster. Well, everybody understands information is important and what quantum information will be used for and where the big practical impact will be. There's still a lot of open questions about that, but we can anticipate that with quantum information, with quantum computing, using quantum entanglement for measurement, we'll be able to do things that we couldn't do before and that's going to have a practical impact eventually. Do you foresee that practical impact extending to our everyday lives? Eventually, I do expect that. We don't know for sure how that impact will be felt. In the case of quantum computing, the best idea we currently have, and it's an old idea which goes back over 40 years to Richard Feynman, is that we can use quantum computers to understand more deeply how quantum systems behave. Physicists like us understand that that's interesting. But it's also important because it can enable the discovery of new types of materials with useful properties, new types of chemical compounds perhaps including pharmaceuticals and so on and all that eventually does affect people's everyday lives and with quantum measurement as well, I think
The flow of water, water clocks. You can have the clock based on watching how someone ages or a human being ages. That wouldn't be a very precise clock, but in principle and if you dug down into the biochemistry, it could be made precise. Many, many different kinds of clocks, but they're all consistent with one another. So when I say the time is what clocks measure, that's more than an operational statement. It has very nontrivial content. It says all clocks that are properly calibrated and understood, no matter what principle they're based on, we'll be able to come to a consistent agreement about what time is. We'll be right back. Welcome back to The Joy of Why. Switching gears a little bit from philosophy here into history of science, it seems to me that a big part of the story of the success of science, especially in what we often call the scientific revolution of the 1600 and later, had to do with the ability to start measuring time pretty well. That it's no accident that Galileo and Huygens and Newton and their successors were around at the same time that good pendulum clocks started to be made. And that you could get the laws of motion in a way that you would have had trouble getting them before you had good timekeeping devices. 2nd Yes. 2nd Do you think that's right, that our scientific progress really depended on an ability to measure time well? It certainly helped and especially if you broaden the definition of time to include the regular motion of planets like Kepler's law that the planets sweep out equal areas in equal times. And, of course, that observation was central to the formulation of Kepler's laws, which together with Galileo's study of pendula and falling bodies.
We have these beliefs about who and when we should intervene. And a lot of the people who get the Carnegie medal of heroism actually die during the process. But you have this built in system, which is they're vulnerable. They cannot help themselves. The help has to come immediately. And I know what to do. I predict that I can do this. Your brain is really good at making predictions about motor behavior. Is your act gonna reach them in time? Are you strong enough to pick them up? Will you be able to get out before the fire reaches catastrophic levels? So your brain makes those predictions very quickly, and it does not require all this conscious processing. So a lot of human researchers wanna think we can only do altruism because we're so intelligent. But I think we share this neurosystem and its capacity with other species, and it doesn't have to be consciously cogitated. Now it's so interesting. You have talked about how the urge for altruism might be a part of our older brain in some sense, our prehuman brain. Can you just talk specifically about which parts of the brain seem to be involved? Sure. There are certain areas of the brain that we know are involved in this transition to caregiving. For example, the striatum, which is rich with dopamine receptors and with oxytocin receptors is influenced by the process of caring for young and mating and cocaine, by the way. Things that you want to approach them because you predict that it'll be rewarding. You approach the offspring because you predict it will make you feel good, or you give to somebody because you predict it will make you feel good. And you don't actually need conscious awareness to do that. If they do brain imaging studies with people and you're allowed to do something more abstract, donate money to a cause, you still have involvement of this same brain area.
