4 years ago
Sean Carroll is a cosmologist and physics professor specializing in dark energy and general relativity. He is a research professor in the Department of Physics at the California Institute of Technology. His new book "Something Deeply Hidden" is now available and also look for “Sean Carroll’s Mindscape" podcast available on Spotify.
So over the weekend I got into your book. Woo. Yes. Yes. It's great. Thank you. I mean, I really appreciate someone like you who's trying to break down quantum mechanics and quantum physics for someone like me. It's very hard to follow. And there was a lot of backing up and trying it again and backing up and trying it again and like going over paragraphs and trying to figure out exactly what it means. It's really excellent and really perplexing at the same time. Well thank you. And you know, there are different styles when it comes to writing popular books. I think there should be different styles. And my particular style is, look, it's not going to be a breezy page turner. But if you read it carefully, like there's not prerequisites. You don't have to come into it as an expert. What you have to come into it is someone who's willing to sit and think about every paragraph. And then hopefully it will be rewarding and you'll truly understand what's going on after doing that. Well it is rewarding because it is fascinating. And the history of quantum physics is also pretty fascinating because I've always wondered, like how did anybody even want to come up with this stuff? And the fact that it was so long ago, was the beginnings of it were in the 19th century? Well 1900 is the typical, literally that year, the turn of the century when Max Planck first got the first hints of it and then yeah, it took another 27 years to put it into final shape. Now for regular people that don't have a background in physics, or they don't, this is, like the whole idea behind it is so bizarre. It's like why would anybody try to figure out something that, one of the things that you said that's really interesting is that quantum physics is used all the time. It's used with exact calculations, but yet we don't really understand it. Yeah, yeah, no, that's the main message of the book really because physicists of course do quantum mechanics every day, whether it's straightforward quantum mechanics, quantum field theory, quantum information, quantum computing, clearly we're pretty good at it. You know, like transistors and lasers depend on quantum mechanics. The sun shining, figuring that out depends on quantum mechanics, the Higgs boson, etc. So to claim that we don't understand quantum mechanics is a little bit weird, but then we have quotes from people like Richard Feynman saying nobody understands quantum mechanics, right? And so if he says that, then there's some authority behind it. And the reason is what we have is sort of a black box, right? We say, you know, I think what I said in a New York Times article I wrote recently is physicists understand quantum mechanics in the same way that someone who owns a smartphone understands the smartphone. Like they know how to use the apps. They can call people. They can make phone calls. They can take pictures. They don't know what's going on inside. And that's physicists with quantum mechanics. They use it. They can make very, very precise predictions. But if you ask them what is really going on, like what is actually happening, what are all the details? They're like, yeah, no, that's not our job. That's a stick to prediction. But to someone like me, that's so terrifying because like the very nature of reality is being examined by people. Like if it is a smartphone, it's being examined by people like me who don't really understand the smartphone. I have no idea what's going on inside a smartphone. I know some words that you used to describe RAM and processors. Probably electrons moving around in there, right? Yeah. And I think in some sense, that's fine. Like most of us don't need to know what's going on inside the smartphone to use it. But somebody should know, right? And my argument in the book is, look, 500 years from now when historians write the history of 20th century physics, they will say two things. One is, my God, these people were so brilliant and creative to invent quantum mechanics. And then they were so afraid to really take it seriously and try to understand it. Like they said, like, stop asking questions about the meaning of reality and what the world is doing. In my mind, what physics is all about is understanding reality and what the world is doing. It's not just about making predictions. Making predictions is good. But we do that mostly because we're curious about what the world is doing. For people outside the world of academia, when I read someone like you saying that you were discouraged from pursuing this and you were literally told that you should be pursuing your work in cosmology and gravitation, that's where it's at. That's serious work, yeah. That seems to me to be so crazy. It's like, if anybody should be pursuing it, it should be people like you. I want to be fair. So, of course, 20th century physics was incredibly successful. And part of the attitude was, look, we have to understand nuclear physics and particle physics. And a lot of it was the center of physics shifted from Europe to the US. And Europe is much more philosophical and you're willing to think about the deep ideas. And Americans are pretty pragmatic and want to build things, right? In particular, at the time, they wanted to build nuclear weapons. And so the idea of just really putting aside deep philosophical issues and putting stuff to work was attractive. And the other issue is, OK, let's say we do demand that we understand quantum mechanics better. How do you do it? Like, what experiment is it there that you can do? As far as we know, the cookbook that we have, even though we don't understand it, works pretty well. Like, what could you type into your smartphone that would help you understand what's going on inside? It's kind of hard to figure out. So I think that those attitudes were wrong, but at least, you know, they're not completely crazy. It's not just that they were afraid of the truth or anything like that. And I also think that it is finally changing now. I think that there's slowly, slowly, slowly more people are appreciating that understanding quantum mechanics is important. What do you attribute that to? A couple of things. One is, I mean, it's good news and bad news. Part of the good news is technology has gotten better. So we're trying to build quantum computers, for example. And guess what? You know, some of the ad hoc rules that we had for doing quantum mechanics might not be up to the task. We need to understand the details a little bit better. The other sadder thing is that so much of fundamental physics is kind of stuck right now, right? We haven't, we literally have not been surprised by a new experimental result in fundamental physics since the 1970s. Wow. So there's one exception to that, which is the universe accelerating in 1998, which is the dark energy. We've had amazing accomplishments in experimental and observational physics. We've found the Higgs boson. We found the top quark. We found gravitational waves, the microwave background, many, many things. But they were all predicted decades ago, right? So progress is driven by being surprised. And it's been a long time since we've been surprised. So some people, including myself, say, well, one of the things to do in that situation is to take a step back and reexamine the foundations. Maybe we can take a broader look and think that we're walking down the wrong path. Now for people who don't have any background in physics, there's a bit of an issue with public perception. And one of the things about public perception is films like What the Bleep? Yeah. That sort of throw this sort of cultish monkey wrench into the, you know, quantum physics is weird enough as it is without adding that that movie was literally created by a channeler, right? A friend of mine, David Albert, who is one of the leading philosophers of physics. And I should also give credit to philosophers here because they have been taking quantum mechanics seriously longer than the physicists have, to be honest. So David is one of the many people who got a PhD in physics and then switched to philosophy because he cared about the foundations of quantum mechanics and no physics department would ever hire him, right? That's hilarious. And yeah, I tell the story. You had it going through the back door. Yeah. I tell the story in the book. Like he wrote a bunch of influential papers as a graduate student. And then he went and said, I would like to, you know, make these papers my PhD thesis. And they said, no, that's not really serious physics. And they punished him by making him write this incredibly technical mathematical paper on quantum field theory just to prove he could do it. And then he's like this, I don't want to take this anymore. I'm switching fields. But anyway, he was in that film. He was in What the Bleep? And they lied to him. They misrepresented themselves. They said, we're doing a documentary about quantum mechanics. And they sat him down for three hours and asked him all these questions, you know, leading questions like, doesn't this mean that we're bringing reality into existence by looking at it? And he's like, no, that's not what it means. Let me explain to you. And then in the final film, there's like 30 second clips of him going, yes, that is a really important question, right? Like completely misrepresenting what he said. And so he went public after that and complained about the film. And he did, in a hilarious story, there was an event, some sort of convention put on in Santa Monica by supporters of the film that they thought it would be fun to get all of the people who were in the movie, What the Bleep do we know, and get them, you know, and talk to them and charge people money to listen to them. But these people were not affiliated with the filmmakers. So they didn't know that David Albert had been completely misrepresented in the film. So they invited him. And he goes to this event in Santa Monica, and he gave a talk, you know, he decided, you know, he wondered, like, should I just go at all? But okay, why not? Let's reach a different audience. And he gave a talk and he said, Look, there's two things you can do when you are faced with fundamental puzzles of reality. One is you can face up to what the world is trying to tell you, and you can accept it and take it as what it is, no matter what you like. The other is you can choose to tell a flattering story about yourself. And the people who made this movie have decided that the mysteries of quantum mechanics are really stories about how they are powerful and have influence over reality and so forth. But it's all nonsense. And the punchline is the audience loved it. They went nuts because what they wanted was a guru of some sort. And like he was just as good a guru as anybody else. So yeah, he had a better story to tell. A reality based reality guru. Yeah, yeah. Yeah. So I think you're right. I mean, I think that quantum mechanics, I've said before is of all the theories in the history of science, the most easily distorted and misrepresented in the popular mind.