A conversation with theoretical physicist and bestselling author of ‘The Order of Time,’ Carlo Rovelli
The decade is drawing to a close — the decade, everyone’s favorite big soggy oblong time unit — and you are probably feeling pretty anxious for one or all three of the following reasons:
- You did not exactly accomplish everything you might have wanted to over the last 10 years.
- You are thinking about the next decade, especially considering the not-unlikely prospect that it will look a lot like the last one, and/or:
- You are thinking about what lies at the end of that next one. Namely, perhaps, the deadline, 2030, at which point the world’s climate scientists say we should be shifted, full gear, into an all-hands-on-deck transition away from fossil fuels if we hope to avoid runaway climate change.
We always have deep anxiety about how we spend our time, but it is especially acute now, with a litany of events to measure our experience against and an onslaught of incoming goalposts to consider. The decade-in-review takes are flooding our feeds, with best of the decade lists exulting more cultural products than we will be able to consume in a lifetime, let alone a handful of years. So are the “next 10 years” prognostications for a future that seems in so many ways pretty terrifying.
At decade’s end, we think: Are we spending our time wisely? Are we spending our time in the right ways and places, doing the right things? How much time do we have left?
Well, I am here to tell you to stop worrying so much. Time, as we experience it, is nothing more than a piddling human construct. The future is almost certainly predetermined on the basis of the extant contours of space-time. And there is no such thing, from a physics perspective, as “ordered time,” anyway. There’s nothing in physics that says the past comes “before” the future, or that the last decade came before the next one.
These are just a few of the truth bombs you’ll find in the works of Carlo Rovelli, the theoretical physicist and author of Seven Brief Lessons on Physics and The Order of Time, both of which were smash international bestsellers, despite being, you know, books about theoretical physics. Because his books are showing up on a lot of those decade-end lists that were making me anxious about how I spent my time, I thought it would be a good excuse to get Rovelli on the horn, and, at this moment on the cusp of decadal transfer when we so very humanly perceiving a monumental passage of time, to talk about time itself.
We touch on time in the age of anxiety, climate change, and technological acceleration, and as a concept that is universally perceived as a common experience and yet nearly totally misunderstood. We talk about the rituals of observing time, why we need them, and whether or not we can change how we move through time at all. Happy 2020s.
The conversation has been edited for clarity.
OneZero: I wanted to talk about some of the lessons of your book, at a moment when people are thinking a lot about, well, time. With the decade ending and people having the kind of anxieties about the future that you talk about, we could use some sort of practical explication.
Carlo Rovelli: Time is something that is a huge concern for us, for all of us. One way or the other, time is always a sort of anxiety. We never have enough time. We lose time. Time flies away. We become older. We’re anxious about the future. We have regrets about the past. Time is a source of emotions. It’s never emotionally neutral for us, time.
How does explaining what’s really happening with time, from the perspective of theoretical physics, alleviate those anxieties? Are you still anxious about time?
I spend my life studying the nature of time. I’ve been fascinated by it since I was a kid, and then in physics, it became more and more a central focus by studying quantum gravity because time changes when you study quantum gravity. However, I don’t know whether I’ve changed because of what I’ve been studying, or just because I grew old. We all grow old and our perspective about time changes just because time has to, right? I’m much more serene now than before with respect to the passage of time. I think it’s critical. It’s what makes us. I’m not afraid of what it takes away from us.
The main message of the book is that time is not a single thing. It’s a very layered notion, many layers. There are many aspects of what we call time. In the book, I try to disentangle them: This is fundamental physics, this is only because we have a brain, and so on and so forth. On the one hand, we discover that some of our experience of time is not really part of nature. Nature is different than what we experience. And that’s a fact. It’s just true. But, however, this does not change the fact that this remains our experience of time. It might be that in nature, past and future are the same, but for us past and future are not the same. The fact that we learn something more does not mean that what we experience is wrong.
We all have learned that in the universe at large, there is no up and down, and that up and down don’t mean anything when you are in interstellar space. So we learn it, we digest it, but then we also understand that here, up and down has a meaning, just because on Earth, it’s a local thing. So we have learned that up and down are not universal, but it does not mean that we can walk on the ceiling. So we still have up and down for us.
Time is the same. We realize that it works completely different on a big scale and small scales. And this is a wonder. But nevertheless, we keep going. Time keeps passing for us. We’ve seen this before and it doesn’t change. Still, the more perspective we have of things, the more we see things from a distance — the better, the easier it is to accept what happens to us.
Why do you think that is? Is it just that understanding the world makes it easier to digest it?
No, I think this is a good lesson that we get from science. We realize that we’re just more or less accidental. And so, we’re not so anxious about the importance of ourselves.
There’s currently a lot of discussion of time in contexts like “We only have so many years to solve problems like climate change” or “Digital platforms seem to suck our time away, or make time pass faster.” What would you say to people who are anxious about time these days?
Well, we certainly are all anxious about time, a lot. And the impression we have is that we’re more anxious today than we were in the past. It’s funny because in a sense we have developed the technology to free time for ourselves from labor — but we haven’t. The more technology, the less free time for ourselves we have. We’re absolutely doing something wrong.
There is also anxiety because of course we, as a species, are in danger because of climate change. And that is justified. Maybe 30, 40 years ago, there was a sense of a more secure future and a more colorful and clear future.
I’m a physicist. I’m not a physician, I’m not a psychologist, I’m not Google. I just studied the time of physics. For me personally, studying how things work — studying what time means on a larger scale — is great and satisfying and relaxing. And the book also tries to communicate that. Come with me for a big, long tour and I’ll show you that time is not what you thought and you can smile from a distance about all that.
Does unraveling the connection between past and future and our experience of both create the biggest surprise that people have when reading the book?
Yeah, there are two big surprises that people always bring up. The first is that the notion of present does not make sense in the universe. If I ask, “What is happening now in a distant place, on a distant planet or a distant galaxy,” [the notion of the present] is meaningless. There’s no common time between us and a place far away. The idea that you and I are talking by phone and we’re in the same present is only because the phone works very well and because light travels very fast between Los Angeles and Marseille. The communication time is so short that we don’t realize that we live in two different temporalities. But if you are far away, it wouldn’t make any sense for me to say what are you doing now, because now is a local thing. It’s not a global thing. There’s no global now. And this is shocking. It forces us to rethink what reality is.
We have known this for a century now since the works of Einstein, and it’s strongly supported by all sorts of experiments. It’s like understanding that the Earth is not flat, and the Earth is moving. The reality is really different than our naive intuition about it.
Time is local. Time passes locally. It’s regional units in its own time. That’s a big thing. But it’s a big thing we understand well. Once you digest it, which takes time, you say, all right, that’s the way it is. On the other hand, what you mentioned about the past and future also was an extraordinary surprise coming from science.
The basic law of the universe is to know the distinction of past from future. That’s a fact. And then there’s the distinction between past and future; it’s very complicated. It’s not written in the groundwork of the universe. It comes out only because we have certain approximations because we don’t know the details. And it’s a long and complicated story. But however, it’s not a story we have completely understood. The real reason for which the past is different from the future, the real reason from which we can remember the past and we cannot also remember the future, it’s something which still escapes us.
What are the implications, in terms of philosophy, that ports over from this kind of thinking? What implications does it have for, say, determinism or free will, that time, is, in a sense, fixed?
It certainly has implications for the meaning of what we mean by reality. And it certainly has implications for free will.
Spinoza, the Dutch philosopher of the seventh century, talked about free will. It turned out to be very much confirmed by science, namely, that free will is just a name we give to the fact that we don’t understand how we ourselves work. We cannot predict ourselves. We are profoundly unpredictable because we are too complicated. And that impossibility of predicting ourselves is what we call free will. In other words, what we call free will is not really compatible with determinism. What we do in the past might very well be determined by what happened, what we do in the future might very well be determined at what happened in the past. But this is irrelevant for us because we’re too complicated to predict. And so effectively we are free, in our way of thinking. And we have to think we are free. We cannot avoid thinking that we are free. Nevertheless, the underlying physics is determinism, and there’s nothing else of this underlying physics.
The future is determined by the past. But this doesn’t mean that we should stop thinking that we are free because it doesn’t help knowing that we determine it. We still have to go through the full process of decision because that’s what we are, that’s our reality. There’s no escape from that.
It is a bit disconcerting. But it shouldn’t be. Because look, even people who very much believe in the soul and in God and in creation, who believe that there’s a God that knows everything — God knows what you’re going to do. He already knows now what you’re going to do today, obviously. He’s God. So you are not free because it’s already known what you’re going to do today. It’s the same problem in a different philosophical context. But it’s a problem we have to face nevertheless. And we have to keep thinking and living believing in our freedom.
“We are never living in the present. We are constantly living in this remembrance and expectation. And it’s our strength, but it is also our damnation because it permits us to live in the present.”
We’re at the end of a decade now. What does it say about us that we need to look back and reflect on what happened in this last 10-year unit of time?
We humans in a sense are very much time machines. We work with time. We think in terms of time. We live in time, which means that we, more precisely, spend our time planning for the future and remembering the past. This is what characterizes us as animal, but especially as humans because humans are much better than most other animals at remembering the past and to imagine the distant future.
You and I know what happened a hundred years ago, more or less, roughly. Not all the cats or birds know what happened a hundred years ago. And you and I can worry about what will happen in a few years. No dog, or cat, or dolphin thinks about his future. Our brain does that, keeps that memory in store to try to decide what to do in the future and to think about the future. So we are never living in the present. We are constantly living in this remembrance and expectation. And it’s our strength, but it is also our damnation because it permits us to live in the present. But we do it constantly and one aspect of that is to try to learn lessons from the past. And that’s good.
Everything we know exists because we have been capable of learning lessons from the past. So we keep doing it. And we do it to increase every moment of our life but we also especially do it on longer scales, and there are some rituals that are opportunities for doing that. And that’s what we do at the end of a year, at the end of the decade, and so on. We did it a lot at the end of the millennium.
Also, it’s actually because we live in time. We need to get asked if time passed. We need to look at the clock. We need to look at the calendar. We need to say, okay, now it’s Sunday, let’s relax a little bit. And then we need this ritual, so we mark the passage of time to feel, to just make it more human or inhabitable for us. And that’s what we are. We are in water. We live in time.
I think it’s interesting that you say that we are never living in the present, that it’s relative, that our own sort of conceptions of time are so scattered — which also seems to mirror in some ways the physics itself.
That’s true. We live a little bit in the past, in the future, in the present, and in the future at the same time together. We definitely do that. But then we narrate ourselves always in the present. We think about ourselves in the present. And the source of our confusion about time, and all this discussion about time, comes from that. When we hear music, we hear a musical phrase, and so we appreciate music because it’s a certain sequence. But in every single moment, we’re just listening to only a single note or a single chord. So how can we appreciate the narrative if we hear just one note at a time? And that’s it, precisely because we don’t live in the present. We strongly immerse in the memory of the previous chord, of the musical phrase, and you anticipate how it will continue.
You said living in the present is our strength and it is also our damnation. Do you think that we can adjust the way that we think about this, and do you think that is a way that we can fundamentally, and in the long run, perhaps avoid that damnation?
Probably not. I don’t think we can change from that, the way we are. Or maybe we can a little bit. But I don’t think we can substantially change our relation to time because that would be hard. A lot of philosophies, religions, or practices have to do with being with time. People who meditate, for example, change their relation to time, have their mind out of time. I think science helps a little bit to understand what is going on by separating the different meanings of time. But it doesn’t really give us a way of doing better what we already know, or not know, what to do. Because we are what we are. We’re very limited creatures and we just follow what we naturally have to be doing. In fact, the best way to go into life is to be accepting what we are rather than to try to change it.
Okay, last question. At the end of this decade, what are you thinking about, when you’re thinking about time?
I myself, like many people, just keep telling myself that I want more of my own time back. I want to say no to more engagements that have time over me. And I don’t want to feel stressed the way I am and the way so many people around me to be. I want to be accepting of what I have.
I think humanity as a whole is realizing that it’s in front of a kind of a fork in the road. Because the planet could be inhabitable for many millennia in the future — or not. I think that the current ecological crisis is forcing us to think how much time we want in front of us as humanity — a little bit, or a lot.
All Rights Reserved for Brian Merchant