James Gleick - Think Again Podcast - TIme Travel/Everything All at Once

Hi there, I'm Jason Guts, and you're listening to Think Again, a Big Think podcast. Since 2008, Big Think has been bringing you big ideas in small, concentrated doses from some of the most creative thinkers around. On the Think Again podcast, we step outside of our comfort zone, surprising our guests and me, your host, with ideas that we didn't necessarily come here prepared to discuss. Based on interview clips from our archives chosen by our producers, today I am very, very happy to be here with James Glick. He is one of our most staggeringly great living science writers.

He's the author of "The Information: A History, A Theory, A Flood." His first book, "Chaos," was the National Book Award and Pulitzer Prize finalist and the national bestseller. His other books include the best-selling biographies "Genius: The Life and Science of Richard Feynman" and "Isaac Newton," both shortlisted for the Pulitzer Prize. James's new book, "Time Travel: A History," is an utterly fascinating journey through the history of an idea that has become part of the fabric of philosophy, science, and our daily lives, even though we can't really do it yet—not really.

Welcome to Think Again, James.

Thank you, Jason. I'm happy to be here.

I'm so happy to have you! I wanted to start with a little anecdote. A couple of days ago, I was walking toward Big Think, reading your book, because I'm like one of the last ridiculous humans who walks down the street in a busy city reading a book. I nearly ran into a bus, and there was an advertisement on the side of the bus for a television show called "Timeless: Protect the Past, Save the Future." So I thought, you know, that's just one of a whole slew of television shows that are starting this fall on the theme of time travel.

Really? Yes. Are we in that time-travel Renaissance?

Maybe we are! I didn't think so, actually, when I started working on the book. In fact, there was a time when I thought—and this is a crazy idea, so I'm a little embarrassed to be admitting this—okay, so you can edit it out if you want. I actually thought maybe time travel is coming to an end. Maybe the golden era of time travel has run its course because we've imagined all of the things.

Well, yeah, that turned out not to be true. While I was working on the book, there were some great time-travel movies, and "Doctor Who" continues to thrive. I don't think we'll ever tire of time travel, especially as physics progresses, unless we get to a point where someone can definitively say to us, "Sorry, bud, that's never gonna happen."

Right. Well, I'm prepared to say that.

Okay, if we want to just, you know, yeah, let's put it out there. It'll kill the buzz, right?

Yeah, but actually I just sort of contradict the premise of my book because the whole point is that our excitement about exploring all the weird possibilities that time offers us has never been as lively as now. So, I should be saying that it makes perfect sense that there are a whole bunch of new network TV shows about time travel.

Can you identify any kind of cultural trigger point as to why there might be a ton of shows right now about time travel? Is there something that happened recently, or is this just the pendulum of media swinging?

It's not just now. There was a time when that question was right on point, and unfortunately, that time was 1895 when H.G. Wells wrote "The Time Machine," which is kind of the beginning of the whole story. Right? So when you asked me that question, I know you're asking about now, and I can and I'll get back to now. But when you talk about cultural trigger points, that's exactly what there was. I mean, at least that's the question that I wanted to try to answer. I mean, why if no one had thought about time travel as an idea before, was it suddenly possible for H.G. Wells to create this powerful fantasy?

I should jump in here and say that your book makes the surprising but evidently well-researched claim that indeed H.G. Wells essentially invented the idea of time travel; that it barely shows up before the book "The Time Machine."

Yeah, it was a surprise to me, and I'm still prepared to be defensive about it because everyone's first reaction seems to be, “Wait, that can't possibly be true. Well, yeah, what about the ancient Greeks? Didn't they at least think about the future?”

Well, it's a tricky question, of course. You think about the future, and you have fortune tellers. There's hardly any cultural tradition that's older than that. Can you predict what's gonna happen to me? Soothsayers, diviners, and all of that. But most of the time, you discover that people are wondering about their own future—you know, you want to know, "Am I gonna live a happy life?" What they were not capable of asking was, "How is the world going to be different for my grandchildren? What wonderful things will they experience and surround themselves with that don't exist in the present?"

So that brings us to technological advancement and also the concept of culture as a whole.

Exactly! I mean, you have to have technological change accelerating to a kind of critical point where a person can look around the landscape and see trains whizzing by where there didn't used to be—where there used to just be farmland—and realized that this newfangled electric telegraph is really altering people's living habits. Right? And then you start to ask, "Well, gee, could things be different? What land and—" you ask, "What marvels will the future bring?"

And that's what happened. So I explore the history of that a little bit. But now—because you asked—it’s very different because we're so used to it. We're so familiar with it; we know all about time travel; we're kind of experts at it from the cradle. So, it's interesting to me that people keep finding new variations.

Yeah, I mean, even my eight-year-old son has come up with an essentially incomprehensible, but I've probed it. I don't get it, but it's a paradox that he seems to think is coherent about time travel, where he's like, "Oh, if I went back in time..." And the best I can understand is that he thinks that time travel is some kind of virtual reality machine where you're actually just amassed all the data from everything that's ever happened. And so when you go back, you're creating new data.

That's a very crazy—

Well, that sounds very advanced indeed.

I can't quite get to the bottom of what exactly the paradox is, but he's onto something there.

You're onto something, I think. And maybe this is part of the real answer to your question, which is we know that the technological change that we're experiencing is all bound up with virtualization, with networking, with cyberspace, with data transmission. Right? We experience different parts of the world virtually on our screens of all sizes, and more and more this is also affecting our sense of time. We experience the past on the same screens that bring us the present. If we see a video of something in terrific high resolution, it may not be something that's happening now; it may be something that happened a very long time ago.

Now, if it's a hundred years ago, right, you can tell because it's grainy or black and white. But more and more, there's a kind of confusion about time that I think has to do with data transmission. So I think your son's onto something there. But it's also the case that science fiction writers are playing with that.

This becomes the end of my book. I didn't know while I was working on what the end was gonna be. I mean, I was always afraid that my books were just gonna peter out. But I was also aware that some weird things are happening in our culture to do with our understanding of time, and I don't understand them all. I don't think any of us understand them.

But to frame it just slightly differently: another thing that's happening is you get a text message, and you get an email, and you see a note on Twitter—all from the same person—and maybe you're meeting somebody, and you have to check, did the email come before the text message? And you start thinking about the timestamps, and you can get confused in daily life. I'm sure examples come to your mind.

Yes, I'm sure they come to your eight-year-old's mind!

So what's interesting is, right, on the one hand, as I listen to you talk about this, I'm thinking, okay, so that's creating a kind of historicity. Like, the young people won't know when things are from because everything is present simultaneously side by side. But at the same time, it seems advanced philosophically in terms of things that you talked about in your book—in terms of the idea that some philosophers—and I think even Einstein may have said—that time becomes less of a significant force somehow.

It's a paradox! It's yet another of the time travel paradoxes.

You're right. It's a kind of historicity in the sense that everything gets muddled together in a world where we're just living in a very complicated, extended present. Right? And what time a thing is from almost doesn't matter. Historical figures are living with us almost as vividly as the people we actually know.

Right, and yet, conversely, you could say that that's a kind of historical awareness that's more acute than ever—that, in fact, we are well-connected with the past. Thus, we can get "Hamilton: The Musical" in hip hop, as people can sort of relate. I mean, young people can connect to Alexander Hamilton in a meaningful way that they couldn't necessarily from a history book.

Yes, and but not only that, you know, Alexander Hamilton has to be translated into a somewhat fictionalized or staged version, or he has to be translated for us in a different way but an equally artificial way—by serious biographers. By the way, I don't mean to imply that Hamilton: The Musical is not serious—it is. But we don't get to see Hamilton.

Right, right! We would actually know what he even looked like. I mean, I wrote a biography of Isaac Newton, and partway through it I realized nobody actually has any idea what Newton looked like. There are a few portraits, right? But if you line the portraits up, they look like different people because they really were lousy painters. So we have to imagine what he looked like!

And then—right—the truth is we're mostly imagining what George Washington looked like. Even that we have—we probably think we have a pretty vivid picture in our head, right? It's made up! But we know exactly what FDR looked like because we've got video. You know, although arguably, going back to some other concepts in the book, that creates a kind of illusion of temporal continuity that isn't entirely accurate anyway, because arguably every FDR at every moment of his life is somewhat of a different person.

Well, that's true. Okay, that's a deep point! But you know, one way to look at our sense of history is to recognize that different media have different time horizons, and we know about a certain segment of the past because the printed word is available to us.

Right.

And we know about a much more recent segment of the past because we've got life; we've got video. Right? And it is different. But what I'm trying to say is that on the one hand, we're connected to the past in vivid new useful ways, and on the other hand, the past and the present are all muddled together, and right, we just feel we're in an unending present.

And I think you're very right to say that we don't really know what it means! And we certainly aren't in a position, I think, to make moral claims about it at this point—to say whether it's better or worse or whatever. Like, you know, one thing that's always motivated me is my continuing sense of confusion or surprise that the past is so weirdly different from the present.

And a kind of historical fiction that I really don't like—in books or in movies—is a kind that makes me think, you're writing about these people from the 16th century as though they were modern, as though they were thinking the same way we think. And actually, it's extremely difficult—almost impossible—for us to put ourselves inside the heads of people who lived in the 16th century. For example, how could there be so many slaveholding abolitionists at the time of the Revolution? You know, there were.

Yeah, many people who were like actively fighting against slavery while owning slaves, to put it in a political or moral way.

Yes, that's true!

Yeah, I mean, it creates sort of ethical tangles for you if you start to think to yourself, "Am I supposed to forgive them because it was a different time?"

And you do forgive them. I mean, people you admire living in the past say the most atrocious things about women, and yet you recognize that it was a different time. But that's not all I'm saying. I'm also saying, if I'm trying to write about Isaac Newton and what he was thinking about gravity—can I subtract from the picture everything that we know about gravity?

I mean, we have a kind of intuition about gravity! We can feel it all around us! Hold out your arm, and then there's this invisible force that's pulling it downward, and how can we imagine a mental picture of the world from which that is subtracted? Because that's what Newton had! You look up the word "gravity" in historical dictionaries and you realize that before Newton started using the word for the thing we're talking about, it meant it was a state of mind. You know, gravity was the opposite of levity, and it just meant taking things seriously.

Right? But if you want to write about the history of science, as I've tried to do, you really need to be able to put yourself imaginatively in this weird mindset.

Right.

Before we get on to the surprise conversations, there was one last thing I want to go back to—time travel—for a second.

This was the surprise conversation!

Well, the surprise conversations are sparked by video clips of interviews from Big Think's archives that we don't know what they're about.

So, okay.

Well, I have no idea!

So, they get emailed to me, and I don't look—honest!

But the last thing I want to say about time travel before we get there is my problem with time travel—my personal problem with time travel—is that it presupposes that the past exists—here in some way still right now. Like, that's the idea that just really bugs me. Like, everyone assumes that you—or everyone who takes the idea of time travel seriously—is assuming that there are these things that are somehow still when, right?

Yeah, and you want me to help you with that?

Well, no! But I guess, like, why isn't that a bigger problem in the discourse of time travel?

Well, or people seem to have an issue with that, or maybe they do. I almost hate to reveal this spoiler about this, I guess there's a sort of spoiler, but I'm just gonna say—I mean, I think you're completely right. You're obviously right! Time travel is impossible, and that's essentially why.

But that's okay! I mean, that's now. I want to say—it's alright because we know all along that time travel is just a fantasy. H.G. Wells knew that he was making stuff up! Sure, I mean, he just wanted to tell a fun story, and accidentally, in the course of justifying—making a story plausible, he came up with a theory of time as a fourth dimension that Einstein also came up with ten years later, right?

You're exactly right! Time travel presupposes that the past is still somehow there as opposed to gone, and even worse, it presupposes that the future is already an existing place.

Yeah, and that is contrary to our most basic human intuition about time, which I will summarize this way: the past is over, it happened, it's gone! Right? And we no longer have access to it. And the future has not yet happened! Some physicists will tell you that, "Yeah, you feel that way, but that's just a human intuition!" And human intuition has again and again throughout history proved to be unreliable. Until Newton explained gravity to us, we thought that up was up and down was down! And now we're perfectly comfortable with the fact that people in outer space have no preferred orientation with regard to verticality—that it's a consequence of gravity!

And maybe our sense of the past and the future is artificial in that same way! Now, if you ask me what I personally believe, I believe those physicists are taking their models too seriously—that this idea of the block universe, in which the past and the future look, according to the equations of physics, to be the same, is a very useful mathematical construct. Incredibly useful—it’s enabled physics to create the marvels that surround us! But it's just a model of the world, and we don't have to say that it tells us definitively that the future already exists.

We are still allowed—speaking philosophically—to imagine that the future is open and you're right—that undermines the premise of most time travel. But isn't that alright? I mean, it's a story!

Oh, it’s—so long as we accept—

Yeah, yes! And so you—then, it frees you to ask, "What's this storytelling us about the world we really live in?" Right? You're gonna organize a particular kind of time travel story in which your hero keeps getting killed, and each time he gets killed, he starts over—or she. I'm thinking of two different versions of this kind of story. What's that a metaphor for? Why did the artist choose to express this particular kind of weird universe? What does it tell us about the universe we really do live in and the artists, and the culture, and the time?

Yeah, okay! This has been so fascinating that I've used up a ton of our time, but we may have—we may end up having only two surprise conversations rather than three about—let’s see.

So, this is Penn Jillette on prayer and the atheist. So, let's see where that takes us.

I very rarely look in this kind of proximity, but I’m not sexting! If you want to know how to be a good leader, watch Donald Trump and don’t do that.

I realized recently—I do something very close to prayer, and I don't want to show any disrespect to people by using the word prayer. But I also want to make a little bit of an argument. Sam Harris makes his argument for atheist meditation; I make a little bit of an argument for atheist prayer. I do something before I go to sleep at night called Penn's guilt roundup, and Penn's guilt roundup is I go through conversations that I've had—like tonight—before I go to bed. I'll think, "So, I really have made that sexting joke when I was at the Big Think."

But I really have done that now! Run through how I could have done that better. I also try to think of what I want and how I can get there.

Now, I'm very fortunate because when I go to my desires, they're not very often material desires because my family is well cared for. But I think about—I used to think about my weight. I would pray to be able to control the wants of my diet, and I do believe with God there's a lot of throwing the baby out with the bathwater. I'm not too referring to baptism there, I'm referring to, huh, I'm referring to the fact that so much of the social and personal elements of religion are really good, I would say maybe more than good—maybe very close to necessary.

Do you feel that science is better off for having largely thrown off religion? Do you feel that it has advanced faster? Do you feel that those scientists were hamstrung in some way by the frameworks through which they were viewing the world? Or, as we were just talking about just now, do you think that maybe some of these new theoretical models that they invent are becoming a new kind of metaphysics or a new religious worldview?

Right, that's—I was gonna go a whole different way with this!

We could go in a direction that you want, that's interesting!

I'm an atheist myself. A lot of scientists are atheists, but some scientists are not atheists. Newton, of course, was profoundly religious. The idea of a universe without God, it just wouldn’t have occurred to him. You're asking if science is better off for having thrown off—ideas were thrown off as a charged phrase—but yes, for having many not having them embedded in it.

And there is—it would be silly for me to deny that there's a sort of conflict between science and religion, because there is. Scientists characteristically view the world in a way that is, let's say, more open—more waiting for evidence—more provisional than religion does—at least as I understand religion. And I don't want to pretend to be any sort of expert on it. You know, some of my best friends believe in God, right? And I don’t think they are any less intelligent—far from it!—or even any less correct about the world than I am. And so, to be intellectually honest, I have to ask myself what that means.

I think that's what Penn was doing when he was talking about prayer. He was asking, "How can I make sense of these ideas that are so much a part of our culture even today?"

So for me—a thing to say about God is to try to understand what it means to people in a more sophisticated, stated way than just, "You know, guy with a beard and white hair, who knows everything that's going to happen or is in charge of things, or created the universe," right? There’s obviously more to it than that!

Just as Penn is saying there's more to the idea of prayer than sending a message to some powerful being who's going to give you what you want—sure, that's not what serious people think prayer is! And I think Penn is right to try to understand a more expansive view of what is meant by the idea of prayer.

When I talk to my friends who are as intelligent or more intelligent than I who have a kind of religious faith, I endeavor to understand how to make sense of what that means. And I do think I have some understanding of it.

And I want to say this about it: there's a different kind of dichotomy, both in religion and in science, that has to do with how we know things and how we know what we know—what we believe about the process of arriving at knowledge.

Okay, which is the area formerly called—in philosophy—epistemology.

Maybe, I know!

Yeah, I don't even want to pretend to know what the law servers call it! What I want to get at is—I'll say simplistically, you know, there are two kinds of scientists. There are scientists who are always in a state of doubt, who consider the normal thing is just to not know things. Right? I mean, this is—I’m thinking of Richard Feynman here. He was eager to say that the universe is a mystery and that most of it is never going to be understood by us humans.

And then all we can hope for is little glimmers of insight here and there! Right?

I believe that there are people in the realm of religion who have the same attitude, who have the same view of faith, right? Who, when they speak of faith, they're not saying, "I know this, this, and this about the origins of the universe." I know that there was a flood and I know that God did this and that. They are talking about faith as a twin of doubt—that faith does not mean certainty!

It means I am believing a certain thing while not claiming absolute certainty about it. I am trying to come to grips with my sense that what we see and touch in the universe is not all there is. Right? And both scientists and people of religion do that, and they do it honorably!

And there are people in both realms who I think do it less honorably. Or at least I should maybe say less to my tastes!

There are scientists who are very confident in what they tell you about the laws of physics and what they know about things that I consider religious questions. If a scientist tells you that he knows how the universe started, right? Or how the universe is going to end, I tend to think they're overstepping their bounds!

And in exactly the way that fundamentalist religious people overstep their bounds when they tell you that wisdom has been handed to us in a certain book, right? And it must not be questioned!

So faith then, in the sense of more to your taste—and I will say more to my taste in sense of it—is, you know, faith that’s oriented—that's around uncertainty but I guess hopefulness in a sense.

But anyone who's doing anything really, really interesting in the world, it seems that there's some motive—even if they wouldn't articulate it as faith—that there's some kind of belief that there's a reason to move in the direction that they're going, and not to just stop doing that, right?

Isn't it possible to argue something different—that we're just, you know, sort of sad creatures who do what we do for reasons that are not accessible to us?

And yes, I'm when I write my next book, it will be with a sense of purpose and a kind of implicit belief that there's some value to it. And who knows what my hidden motivations are! But maybe it's also possible that I'm just doing it because it's a thing to do.

A thing to do!

Okay, well I think on that note before we dissolve into an existential soup! On that deflating note, yeah, let's see what the next one is! This is David Eagleman, neuroscientist, and it's called "Your Time-Bending Brain."

So this is an area of interest to me, and my lab's been studying this for a while. This is why time is rubbery and can speed up or slow down. And the experiment had never been done about why time seems to move in slow motion when you're in a life-threatening situation.

But I talked to so many people, and I'd experienced it myself, that I wanted to study that. So I found a way to study it by dropping people from a 150-foot tall tower and measuring their time perception on the way down. And that, plus several other experiments we did in my lab, led me to understand that people don't actually see time in slow motion during an event.

Instead, it's a completely retrospective assessment. In other words, when you're in a life-threatening situation, your brain writes down memory much more densely, and then retrospectively, when you look at that, you have so many details that you don’t normally have that it seems as though it must have lasted a very long time—that's the only interpretation your brain can make!

So time—your assessment of how long something took—has a lot to do with how much energy your brain has to burn during the event and how much footage you have of the event.

A thing that everybody knows about time is that our perception of it varies. The observation that sometimes time passes quickly and sometimes time passes slowly for us is one of the oldest of human observations. And people have known that—certainly Shakespeare knew it! And people, you know, we know that time flies when you're having fun, right?

Now we also know it in a slightly more sophisticated way—that music, as an art form, is capable of wreaking havoc with your sense of time—with your perception of time. That's one of the games that music plays, is creating a sense of fast motion and slow motion by playing with, as David Eagleman is saying there, with information flow.

I mean, I think he's—I think that's a smart way to think about it—that a way for a psychologist to explore the perception of time is to think in terms of how information is processed and stored in our brain, right?

Fine! For my narrow purposes and my time travel book, I decided I actually wasn't that interested in the perception of time because that part of it seemed a little obvious to me.

I mean, another thing that we all know is that the years seem to pass a lot more quickly as we get older, sure! You know, when you're six years old, a month is a lifetime!

And when you're 70 years old, a month can go by really tragically quickly! Interestingly, also, it seems like time passes more quickly in retrospect.

I remember when we first had our son, everyone coming along to us and saying, "Oh, it goes so fast! You know, he's gonna grow up!"

With an exact accent, it kind of—and then there were, you know, months and years where we were like, "That's not going so fast!" Doesn't feel like it's going all that fast, you know?

I mean, but they’re looking back on it, you know, at a vantage point of 25 years later or whatever.

Yeah, and all of this—so there are a lot of things like that, but not that interesting—that I'm not saying they're not interesting, that we kind of know. And I think it's good that there are people who explore these things and try to understand them better, right?

But it felt like a kind of side issue for me—yet obviously related! Because what my book is most fundamentally about is our understanding of time, and that's a complicated thing—very complicated thing—and that has changed dramatically during the last century.

And I guess my point is that this all does feed into time travel storytelling because we're learning new things all the time about the way time passes and the way kind of flows, and we are therefore forced to think about what that sentence I just said means. Does time pass? Does time flow?

I mean, we're not even getting into the much more complicated question, which obviously this underscores of like, "What is time at all?" and how slippery that concept is, and how aware of that we all are on some level.

I actually knew that I was going to have to deal with that question in the book, and I won't pretend that I actually answered the question, but I hope I shed some light. Because I felt that that was the time travel story trying to shed light on that question!

Yeah, indeed! I mean, we have a concept of moving across something that we don't even have really the faintest real idea of what it is. That's pretty good!

Whatever you say, you immediately know it's wrong! If we're moving—are we moving across it, or is it moving through us, or is it moving with us? Are we floating in—is time a river? It would be—I would actually be really interested to simply interview a random sampling of 500 people and ask them the question, "What is time?" You know, and hear what they say! Or you could look in the Oxford English Dictionary and read the, you know, 10,000 words they devote to trying to answer that question!

I'm sure James Glick, thank you so much for being on Think Again. This has been fun, and—as I promised in the beginning—divergent conversations!

Alright, thank you! It's fun for me too! Thanks very much!

And that's it for this week's episode of Think Again. For those of you who are out there and listening to the show and enjoying what you're hearing and finding it intellectually stimulating, or you have responses that you don't think we addressed or whatever, I'd love to hear from you!

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