Speaker 1: Welcome to Stuff to Blow your Mind from how Stuff
Speaker 1: Works dot com. Hey you welcome to Stuff to Blow
Speaker 1: your Mind. My name is Robert Lamb and I'm Joe
Speaker 1: McCormick and Robert. I've got a question. I know you've
Speaker 1: got a good answer for. Do you ever do that
Speaker 1: thing where you try to catch an awareness of now?
Speaker 1: I feel like it's it's sort of the five year
Speaker 1: old game, right. I remember I learned to play this
Speaker 1: with myself when I was a little kid, where I
Speaker 1: would think, no, win is now, No, it's now, it's now?
Speaker 1: How soon is now? Exactly? Um? Yeah, it is like
Speaker 1: a child's game to a certain extent, you know, as
Speaker 1: you begin to become aware of time as an abstraction
Speaker 1: and you ask yourself what is now? And then, of course,
Speaker 1: one of the things about this question is you probably
Speaker 1: keep asking yourself this question throughout your life, like there's
Speaker 1: there's no putable answer that ever presents itself. Yeah, I
Speaker 1: feel like so we have the sensation that we live
Speaker 1: in the present moment, right, there is this idea of
Speaker 1: the present. I think it's pretty much there and most
Speaker 1: people's minds, because all cultures seem to have this idea
Speaker 1: of the present. Maybe not all cultures, but most do
Speaker 1: um And you've got this feeling that the past is
Speaker 1: behind you and that's already happened, and the future is
Speaker 1: in front of you. But in between you have this
Speaker 1: present moment that I think is in a lot of
Speaker 1: ways comparable to our relationship to the unconscious mind. And
Speaker 1: what I mean by that is and you get the
Speaker 1: feeling that a lot of your thinking and a lot
Speaker 1: of what your brain does is unconscious. But you can
Speaker 1: never catch the unconscious part of your mind in action. Right,
Speaker 1: every time you try to be aware of how your
Speaker 1: mind is working unconsciously, suddenly you're not unconscious anymore. You're
Speaker 1: conscious of it. Like the flashlight of metacognition kicks on,
Speaker 1: and you you can't be aware of un consciousness. Yeah,
Speaker 1: it's the feeling of being strapped to a train. It's
Speaker 1: hurtling farward through time and you can't quite turn your
Speaker 1: head around to see all the various engine parts and
Speaker 1: wheels and what have you that is propelling you. Yeah,
Speaker 1: and I think that now, the now is kind of
Speaker 1: like this. It's like you suspect that there was just
Speaker 1: a now, but that now is no more. You you
Speaker 1: can't really turn your attention to it. So you have
Speaker 1: this general since you live in the moment of now,
Speaker 1: but you've at least for me, I have never really
Speaker 1: been able to fully become aware of the present. The
Speaker 1: more I try, the more it's sort of becomes the
Speaker 1: slippery tadpole where I'm trying to catch it between my
Speaker 1: fingers and it's always squirming away. I know that there
Speaker 1: are future now is coming, and I'm aware that past
Speaker 1: now is have gone by, but I can never really
Speaker 1: find the now of now. So that leads me to wonder,
Speaker 1: is there a now? Is there even such a thing
Speaker 1: as the present? And if there is, what is it?
Speaker 1: And if there isn't, what is this sense of now
Speaker 1: that we experience and how does it shape our lives? Yeah,
Speaker 1: it's a fabulous question, uh, and one that's so easy
Speaker 1: to dismiss because we we have all these various metaphors
Speaker 1: that will get into to sort of understand time, to
Speaker 1: sort of tie time up in a little, neat, little
Speaker 1: package and set it on a shelf so we don't
Speaker 1: have to really worry about it. Uh. And one of
Speaker 1: those metaphors that we end up using, I think time
Speaker 1: travel movies, time travel TV shows, I'm I'm watching another
Speaker 1: one right now, and uh, and you know, the characters
Speaker 1: are always moving around and picking what point in time,
Speaker 1: what now they wish to go to, And it makes
Speaker 1: you think of your now, your present moment as a
Speaker 1: location on some sort of a line or a grid. Now,
Speaker 1: for my own part, as far as mindfulness exercises go,
Speaker 1: that that attempt to focus in on the present moment
Speaker 1: and sort of unshackle yourself from past and future, I
Speaker 1: think a lot of it does come down to focusing
Speaker 1: on a rhythmic, ongoing process as opposed to trying to
Speaker 1: you know, grab that moment, that now, or whatever you
Speaker 1: want to call it. And usually the focus is on breathing,
Speaker 1: because to focus your awareness upon your own breath is
Speaker 1: to focus on the most immediate conscious exercise of the body.
Speaker 1: It always reminds me of various adages about how God
Speaker 1: is as close to you as your own breath, and
Speaker 1: I believe in Islam, uh, they use the jugular or
Speaker 1: the veins of the body in the same way, so
Speaker 1: like it's as close to you as your own blood
Speaker 1: or your own circulation. This flow of blood, the movement
Speaker 1: of change through your body and through this pinpoint of experience. Uh.
Speaker 1: And and when when I say pinpoint again, if you
Speaker 1: try and grab that pinpoint and it it just you
Speaker 1: cannot grasp it. And there are so many I mean,
Speaker 1: I constantly think of the way literature explores this. I
Speaker 1: mean it's a it's a recurring theme and a lot
Speaker 1: of our favorite books and stuff about how whenever somebody
Speaker 1: has something good or something they want to remember, they
Speaker 1: can never have it in the moment, you know, Oh yeah, yeah,
Speaker 1: I mean so many books are about life and death.
Speaker 1: Corman McCarthy has said that all great works of literature
Speaker 1: about life and death. He can't have life and death
Speaker 1: without time. He he has a great quote from The
Speaker 1: Crossing that I'll read real quick. Snowflake. You catch the snowflake,
Speaker 1: but when you look in your hand, you don't have
Speaker 1: it no more. Maybe you see this day chatto, but
Speaker 1: before you see it, it is gone. If you want
Speaker 1: to see it, you have to see it on its
Speaker 1: own ground. If you catch it, you lose it. And
Speaker 1: where it goes there is no coming back from not
Speaker 1: even God can bring it back. Oh that's great. Then
Speaker 1: now then now is like the snowflake, Like if you
Speaker 1: want to hold it in your fingers, it's gonna immediately melt. Yeah,
Speaker 1: it's this, it's this kind of this uh, this concept
Speaker 1: that we use to make sense of our experience of time.
Speaker 1: But when you try and and study it, when you
Speaker 1: level physics, neuroscience, philosophy. We're going to expose a number
Speaker 1: of the different tools you might use to try and
Speaker 1: cap sure than now, but time after time, that snowflake
Speaker 1: just melts away into nothingness. So this will be the
Speaker 1: first part of a two part episode, right, that's right.
Speaker 1: So I think in the first one we're going to
Speaker 1: focus more on like the the experience of time as
Speaker 1: it relates to physical reality, and then in the second one,
Speaker 1: we're going to try to look a little bit at
Speaker 1: the philosophy of time and at neuroscience and psychology and
Speaker 1: what they can shed light on the experience of now. Right,
Speaker 1: And there's there's gonna be a lot of interconnectedness too.
Speaker 1: So this is definitely a two parter to listen to
Speaker 1: in order. Now, I would imagine if I was five
Speaker 1: or six years old and playing this win is Now game.
Speaker 1: I wasn't the first person to do this. This has
Speaker 1: to go way back in human history. I can imagine
Speaker 1: that the ancients were probably probably writing about this mystery
Speaker 1: of what is the now? Even though we have a
Speaker 1: sense of now, how come it's so hard to catch?
Speaker 1: Oh yeah, I mean the great thinkers throughout time have
Speaker 1: tackled this, and most of them have seemed rather frustrated
Speaker 1: by the nature of and by the elusive nature of now.
Speaker 1: For instance, Aristotle wrote about it in the Physics, which
Speaker 1: is a fourth century b c. Text. He said, for
Speaker 1: what is now is not a part. A part is
Speaker 1: a measure of the whole, which must be made up
Speaker 1: of parts. Time, on the other hand, is not held
Speaker 1: to be made up of nows. And he goes on
Speaker 1: again the now, which seems to bound the past and
Speaker 1: the future. Does it always remain one and the same?
Speaker 1: Or is it always other and other? It is hard
Speaker 1: to say. In Aristotle goes on to address the difficulties
Speaker 1: of time on both counts. Time is a series of
Speaker 1: nows lined up like beads, h you know, back to back,
Speaker 1: and the notion that now is a termination point on
Speaker 1: a line extending infinitely in either direction. I think this
Speaker 1: serves to hint towards a debate that I think most
Speaker 1: physicists would come down on one side. Of and the
Speaker 1: debate is whether time is composed of continuous or discrete quantities.
Speaker 1: Now you can think of all the the objects in
Speaker 1: the world is made up of either continuous or discrete qualities.
Speaker 1: One example would be that water seems to be a
Speaker 1: continuous quantity. It just sort of like flows and there
Speaker 1: doesn't seem to be units of it. But in fact,
Speaker 1: through chemistry, we know that there are units of water.
Speaker 1: There are h two O molecules. If you get down
Speaker 1: to the molecular level, you can see that it is
Speaker 1: discrete and not continuous, and you sort of have to
Speaker 1: wonder if time is the same way. Time feels like
Speaker 1: this continuous quantity, that there couldn't be like a single
Speaker 1: smallest indivisible unit of time, could there be? Well, well
Speaker 1: we will get into that a little but in this episode.
Speaker 1: But it is one of those things where you can't say, oh,
Speaker 1: how many so you want to meet me at the
Speaker 1: coffee shop in three hours? How many times is that?
Speaker 1: Can you can you break that down into indisputable um,
Speaker 1: you know, micro portions of time. Well, I mean, obviously
Speaker 1: you can have units of time, because we do, but
Speaker 1: they they don't seem to be set by nature. There
Speaker 1: doesn't appear to be a physical bottom limit to dividing
Speaker 1: time into pieces. Yeah, there's not a like a lego
Speaker 1: brick ification of time. I mean, if there is, it
Speaker 1: is a brickification. It's it's the dividing up of time
Speaker 1: into blocks that we can make sense off, but not
Speaker 1: the the the unearthing of the pieces that make it up.
Speaker 1: Though at the same time, this is going to keep happening,
Speaker 1: isn't it. Later in this episode we will mention that
Speaker 1: for the purposes of science there might be sort of
Speaker 1: bottom units of time, but not necessarily for the universe itself. Yes, well,
Speaker 1: we'll come back to that because I have more to
Speaker 1: say on that as well. But for now, I guess
Speaker 1: we should we should back up a little bit and
Speaker 1: talk about just the basic experience of of now and
Speaker 1: basic experience of time. Yeah, I guess we should look
Speaker 1: to uh to physics for some definitions, Like if you
Speaker 1: wanted to have a measure of time that wasn't just
Speaker 1: you know Einstein's cheeky answer. Einstein would say, what's the
Speaker 1: definition of time? It's what you read on a clock.
Speaker 1: But you know he's joking, Like, if you're trying to
Speaker 1: come up with the best physical universe based approximation of
Speaker 1: what we mean by time? What is it? Well, I
Speaker 1: mean it's at its most basic level, time is the
Speaker 1: rate of change in the universe. The rate of change
Speaker 1: in the universe, so the relationship between one point and
Speaker 1: the next point in the history of an object. Yeah, though,
Speaker 1: doesn't it get It gets tricky when you start bringing
Speaker 1: in time based terms than to describe it when you
Speaker 1: bring in history, etcetera. Yeah, that's true. It's one of
Speaker 1: those things like, uh, you know, the classics and in
Speaker 1: the art of motorcycle maintenance question like how can you
Speaker 1: define quality without invoking the concept of quality? How do
Speaker 1: you define time without invoking the concept of time? Yeah,
Speaker 1: I mean basically though, you have to say, all right,
Speaker 1: we are creatures that live in a universe where there
Speaker 1: is change, and stemming from that, we haven't live in
Speaker 1: a universe of causation to where uh, the cause must
Speaker 1: precede the effect of something, which certainly becomes important when
Speaker 1: you start thinking about time travel and what have you.
Speaker 1: We age the planets move around the Sun and things
Speaker 1: fall apart, right entropy, Yeah, and this is often linked
Speaker 1: to time. Right. Time seems to have something to do
Speaker 1: with the direction of entropy in the universe. As as
Speaker 1: things tend toward disorder thermodynamically, the time interval goes up. Yes. Now,
Speaker 1: early humans quickly took note of the cyclical nature of
Speaker 1: sun and stars and moon and the seasons, and they
Speaker 1: utilize this information to organize their lives. Natural time mattered,
Speaker 1: local time mattered, and for more ancient societies, the understanding
Speaker 1: of time was as cyclical as the cosmic movements they observe.
Speaker 1: The sun rose and set, people were born, and people died,
Speaker 1: all in an endless cycle. We've touched on on this
Speaker 1: this version of time many times on the podcast, and
Speaker 1: I think it's interesting to look to ancient societies and
Speaker 1: see how much these markers of time, passage, and the
Speaker 1: cyclical nature of the seasons and stuff really seemed to
Speaker 1: matter to them. Like they often invested huge amounts of
Speaker 1: resources and energy into projects for like marking celestial events
Speaker 1: that would be recurring events. Yeah, why did they do that?
Speaker 1: I mean, was that really necessary? I would I would
Speaker 1: love to do a future episode where we explore this
Speaker 1: more because one of the books that I used in
Speaker 1: research here was Dan Falks In Search of Time, The
Speaker 1: History of physics and philosophy of time and excellent volume,
Speaker 1: and he devotes a lot of time to discussing these
Speaker 1: ancient cultures and ancient people's, the Neolithic treatment of time, etcetera. Yeah,
Speaker 1: that that would definitely be worth an episode. Like what
Speaker 1: were the reasons these cycles were so meaningful in their lives? Yeah?
Speaker 1: And it certainly was meaningful because that the repetition of
Speaker 1: the cycle made things matter. I think it was really
Speaker 1: Audio who said that encyclical time. Uh, any incident in
Speaker 1: your life only matters insofar as it repeats uh an
Speaker 1: archetypical moment of significance. Yeah. I think we can see
Speaker 1: this distinction between the idea of cyclical time and linear
Speaker 1: time showing up also in the types of like stories
Speaker 1: that people like to consume. Yeah, Like, is is a
Speaker 1: story meaningful because it recapitulates a story that's already been
Speaker 1: told a million times? Or is it meaningful because it
Speaker 1: tells a new story that's never been told before? Exactly? Now,
Speaker 1: of course, this human society has became more modern, they
Speaker 1: largely discarded cyclical time in favor of linear time, all
Speaker 1: with a great deal of help from calendars and clocks. Now,
Speaker 1: but before we go the Devil's contracts. Yes, Now, now,
Speaker 1: before we go any further, uh, I thought we might
Speaker 1: take a moment to talk about metaphors, because we've already
Speaker 1: stepped in a number of them, and we're going to
Speaker 1: continue to to use them intentionally and accidentally, as we
Speaker 1: discussed now in time, I think it's just worth letting
Speaker 1: you know out there that we have already had to
Speaker 1: stop and edit out like at least a dozen times
Speaker 1: we use the word time, right, So if you get
Speaker 1: sick of hearing it a dozen times, then then just
Speaker 1: know that we there were like three dozen instances that
Speaker 1: were cut out, but it totally pervades all of our
Speaker 1: metaphors and our figures of speech, right, Yeah, I mean
Speaker 1: that that's the really the damning thing about about time
Speaker 1: is that nothing in our lives is as close and
Speaker 1: personal and yet at the same time so abstract and
Speaker 1: resistant to our understanding. But still we try, right, and
Speaker 1: one of the ways that we we try to understand
Speaker 1: time is we we roll out metaphors. As with consciousness.
Speaker 1: Parts of part of the problem is that we're just
Speaker 1: attempting to understand the thing from within it, uh, even
Speaker 1: more so than the human mind. We can't step outside
Speaker 1: the human experience of time to consider the thing. In
Speaker 1: that book I mentioned by by Dan Falk in Search
Speaker 1: of Time, The History, Physics and Philosophy of Time, he
Speaker 1: points out that we've long turned to the river as
Speaker 1: a way to understand the quote unquote flow of time.
Speaker 1: And that's great because the river metaphor. He's totally right
Speaker 1: that this is one of the most common metaphors used
Speaker 1: for how time progresses. But it it is both a
Speaker 1: great metaphor because the river is unstoppable and you have
Speaker 1: no control over it. But it's also not quite right
Speaker 1: because you can stand in a river and let it
Speaker 1: flow past you. So for the river metaphor to really work,
Speaker 1: you would have to sort of be part of the river,
Speaker 1: and you would have to be on a boat, which
Speaker 1: means it's essentially just another technology metaphor. Right. But even
Speaker 1: in a boat, you can paddle, you can swim against
Speaker 1: the current, you know all that, you would have to
Speaker 1: essentially be the water itself, with no power whatsoever to
Speaker 1: control your position upstream or downstream in the river. You
Speaker 1: would just flow and that's all you could do. Yeah,
Speaker 1: it's one of those metaphors that breaks down upon close examination.
Speaker 1: As Fault points out, a river flows in respect to
Speaker 1: the shore. But what are the banks of time? Um?
Speaker 1: Another one that comes up a lot, and especially with
Speaker 1: with modern for modern minds. Uh. Again, a technological metaphor
Speaker 1: is that emotion pictures? Uh, it's it's a there's a
Speaker 1: film playing and we are we're watching a portion of it,
Speaker 1: and then there is a played portion and an unplayed portion,
Speaker 1: and it's physically present in the you know, when you're
Speaker 1: looking at a you know, an old school projector. But
Speaker 1: also with the film, like you say, the river moves
Speaker 1: with respect to the shore, the film plays with respect
Speaker 1: to the viewer the projector. It would have to be
Speaker 1: that the film just is a thing that plays itself
Speaker 1: and that's all there is. Yeah, And in a way,
Speaker 1: these examples some of a lot of the problems and
Speaker 1: understanding time, especially as we get into the often explored
Speaker 1: idea the time is an illusion because it feels real.
Speaker 1: It's a central aspect of our conscious experience. It's a
Speaker 1: part of the world we and as we see it
Speaker 1: and understand it. But yeah, when you when you try
Speaker 1: to focus in on it and grab it by the neck,
Speaker 1: it just fades away, you know. We can mention this
Speaker 1: in a bit. But I think that there are some
Speaker 1: physicists who will say that time is an illusion in
Speaker 1: that time itself is not necessary to describe the universe.
Speaker 1: But I think they're in the minority, right, I mean,
Speaker 1: I think the majority of physicists would say, yeah, time
Speaker 1: is a real thing. It's just that there's certain aspects
Speaker 1: of it that are an illusion. Our our experience of
Speaker 1: time is an illusion because it privileges this sense of now,
Speaker 1: that time is like happening, and that maybe the future
Speaker 1: has the potential to change and could be one way
Speaker 1: or another, whereas you know, just looking at the physics,
Speaker 1: there's no real reason to suspect that. Now. On on
Speaker 1: the heels of this motion picture analogy, I should point
Speaker 1: out that Max Tegmark, who will will come back to
Speaker 1: again later on Max he likes to point out point
Speaker 1: to a film on a DVD as a suitable metaphor.
Speaker 1: So in this our life is a movie and space
Speaker 1: time is the DVD. So just consider a DVD copy
Speaker 1: of Risky Business? Is that his example or yours? Um? Oh?
Speaker 1: You know, I can't. I can't remember because I keep
Speaker 1: thinking back to this analogy and I always think of
Speaker 1: risky business for some hand, for some reason, And I
Speaker 1: can't remember if that was my flourish or his. But
Speaker 1: the idea here is the DVD doesn't change. So you
Speaker 1: can't say Tom Cruise is traveling through the DVD. He's
Speaker 1: traveling through the lifespan of the film, and so is
Speaker 1: the viewer. Speed it up, slow it down. But the
Speaker 1: physical DVD doesn't change. Yeah, the movie just exists, though
Speaker 1: you can watch it. Yeah, then again the viewer from
Speaker 1: the outside of the way. Yet again, all the metaphors
Speaker 1: fall apart. Now, every ancient society developed a calendar system
Speaker 1: of some sort, even prehistoric people exposed to the naked
Speaker 1: cosmic expanse of her head, they noted the movement of
Speaker 1: the heavens. And here's just another cool bit about technology
Speaker 1: and our our measurement of time. I was reading James
Speaker 1: Burke's The Day of the Universe Changed, Uh, which was
Speaker 1: one of his like two classic works on the history
Speaker 1: of science and technology, and he made this point about
Speaker 1: these of clocks and medievil times. He says that that
Speaker 1: without calendars and clocks are written records memorable events marked
Speaker 1: the time, such as seasonal activity surrounding the harvest, which
Speaker 1: goes in with what we've been saying already. So that way,
Speaker 1: it almost be like saying that instead of using a
Speaker 1: ruler to measure distances, you'd measure distances by your by
Speaker 1: your relationship to landmarks, you know, familiar important landmarks. And
Speaker 1: so instead of using some kind of standard measure of time,
Speaker 1: you measured them by relationship to festivals and important events. Right,
Speaker 1: and here's here's what he had to say. Additionally, quote,
Speaker 1: country people were intensely aware of the passage of the year.
Speaker 1: But between these seasonal cues, time in the modern sense
Speaker 1: did not exist. Even in rich villages, which could afford
Speaker 1: a water clock or a sun dial, a watchman would
Speaker 1: call out the passing hours, shouting them from the church tower.
Speaker 1: The hours would echo through the surrounding countryside, shouted along
Speaker 1: by the workers in the field. Units of time smaller
Speaker 1: than an hour were rarely used. They would have no
Speaker 1: purpose in a world that moved at the pace of nature. Man,
Speaker 1: that's fascinating to consider. I mean, we so live in
Speaker 1: a world of minutes and seconds. Now, I think could
Speaker 1: it be that it's because we're surrounded by all these
Speaker 1: digital devices that keep time accurately and of course we're
Speaker 1: on top of that, we're constantly bemoaning the relativistic experience
Speaker 1: of time, you know, where we look at the clock
Speaker 1: and we're like, we say, Jesus, where did that hour go?
Speaker 1: I've been working for an hour. It doesn't feel like it.
Speaker 1: Or you think, oh, man, I I've only been waiting
Speaker 1: here ten minutes. It feels like an hour. So it
Speaker 1: is you do wonder to what extent we we have
Speaker 1: this this rigid timekeeping system and it ends up backfiring
Speaker 1: on us because our bodies and our experience of time,
Speaker 1: it still moves at the pace of nature. Do you
Speaker 1: think that maybe hyper awareness and hyper acute keeping track
Speaker 1: of time actually makes us more like cleared to squander time.
Speaker 1: I would say the intuitive thing would be the opposite,
Speaker 1: that if we're hyper aware of time, that we you know,
Speaker 1: we'd be very careful how we spend our minutes. But
Speaker 1: I wonder if there could be kind of some some
Speaker 1: backfiring mechanism there, because I often think when I'm sitting
Speaker 1: around sort of watching the clock while I wish I
Speaker 1: was doing something else, I can really waste a lot
Speaker 1: of time on the internet. Yeah, I find that to
Speaker 1: be the case too. I mean part of it. Maybe
Speaker 1: I just have poor time management skills, but uh, I'll
Speaker 1: often find myself in the trap of thinking, oh, I
Speaker 1: have I have two more hours before a particular you know,
Speaker 1: self imposed deadline, and and then I'll squander fifteen minutes.
Speaker 1: And then after fifteen minutes is passed, then I'll then
Speaker 1: not Then I will say, oh, my goodness, fifteen minutes
Speaker 1: is over, and then I'll feel bad for squanding theft
Speaker 1: I can say from my own experience, I honestly think
Speaker 1: that I make best use of my time when I'm
Speaker 1: not really keeping track of time. Yeah, I think I'm
Speaker 1: most productive. I think I use my time in ways
Speaker 1: that i'm I'm glad. I'm the most glad about out
Speaker 1: after it's done, when I'm not noticing the minutes going by.
Speaker 1: All right, So, for the individual experiences of the productivity
Speaker 1: may vary, but Falk points out that linear time becomes
Speaker 1: a cornerstone of the Western world and may have paved
Speaker 1: the way for the scientific and industrial revolutions quote which
Speaker 1: in turn triggered an an affinity for reason and a
Speaker 1: sense of progress. By the end of the seventeenth century,
Speaker 1: Europeans viewed time as an abstract entity, holy, independent of
Speaker 1: human activity. Oh, the horror, the de personalized time. That
Speaker 1: it's not it's not really your time as a measure
Speaker 1: of your experience, but that it's this universal quantity that
Speaker 1: you must adhere to. Yeah, we're stuck with clock time
Speaker 1: and on the surface of things that it seems like
Speaker 1: a rigid and unflinching order. Right, that this thing that
Speaker 1: we're we're enslave too. Right, we measure the passage of
Speaker 1: time in a dreary procession of seconds, minutes, hours, and years.
Speaker 1: But this doesn't mean that time actually flows at a
Speaker 1: constant rate. Even the use of of of a sun
Speaker 1: dial is the visual observation of the Earth's movements. And
Speaker 1: and even this is not a set speed. The speed
Speaker 1: of Earth's rotation is slowing because some of our angular
Speaker 1: momentum is being transferred via tidal force to the Moon's orbit.
Speaker 1: Now granted it's you know, slowing at a it's a
Speaker 1: that's occurring at a very slow pace. But still this
Speaker 1: is not a constant thing in the universe. Oh yeah,
Speaker 1: I mean a couple of billion years ago, the Earth's
Speaker 1: today was much shorter. In a couple more billion years,
Speaker 1: it will be much longer, and just think how much
Speaker 1: you'll be able to get done. And that's not that's
Speaker 1: without even getting into the topic of time dilation and
Speaker 1: the observable reality the time flows at a different rate
Speaker 1: depending on mass and speed. Which will be touching in
Speaker 1: on that more as we proceed. And of course we
Speaker 1: don't need machines to keep rhythm with the universe. Animals
Speaker 1: and plants, uh, you know, all boast internal clocks to
Speaker 1: keep them in sync with their environment. And the brain
Speaker 1: plays a key role here. I have another quote from
Speaker 1: from Fall here that I thought was wonderful. Somehow we
Speaker 1: take in a vast array of chaotic sensory data from
Speaker 1: our environment and organize it into a meaningful picture of
Speaker 1: our surroundings. But it is an ever changing picture. It
Speaker 1: is a picture that evolves in time, a picture rooted
Speaker 1: in time. Human beings have a remarkably sophisticated ability to form, store,
Speaker 1: and recall these mental images. Memory, it seems, is all
Speaker 1: about time. Now may just last a flickering moment, but
Speaker 1: in our minds it can endure for decades. That's fantastic.
Speaker 1: But I wonder about even the lasting of flickering moment
Speaker 1: because what is going on in that flickering moment it
Speaker 1: is now really being registered. I think we may have
Speaker 1: some bones to pick with that. You know. All of
Speaker 1: this makes me think of scientist Michael Graziano's attention schema
Speaker 1: model of human consciousness. This is where attention and control
Speaker 1: of attention play the crucial role in the human experience. Uh.
Speaker 1: Coming back to the idea that time is the rate
Speaker 1: of change in the universe, and then our brain service
Speaker 1: service in navigating this world of change. It would make sense,
Speaker 1: wouldn't it that our brains would mirror the movement of causation.
Speaker 1: The lion must attack before it kills, the fruit must
Speaker 1: ripen before I can eat it, and thus my awareness follows. Yeah,
Speaker 1: this draws a connection to something that I've discussed on
Speaker 1: some other podcasts before. I think this came up in
Speaker 1: old episodes of forward Thinking. But the idea of intelligence
Speaker 1: being a function of time, this is something we don't
Speaker 1: often think about. But imagine you were able to solve
Speaker 1: really really difficult brain teaser type puzzles, but it took
Speaker 1: you a thousand years to do it. Would that be intelligence?
Speaker 1: I mean, would you call that intelligence? By by that
Speaker 1: measure you could take all kinds of natural phenomena that
Speaker 1: we don't usually think of as intelligent and call them intelligent,
Speaker 1: Like you could call evolution itself intelligent by that measure,
Speaker 1: because it solves amazingly complex, difficult problems. It just takes
Speaker 1: millions of years to do it. Um. So at that point,
Speaker 1: is it even intelligence or is intelligence something about acceleration
Speaker 1: through time of solutions? Well, yeah, and that you get
Speaker 1: into you into questions about emergent intelligence, the idea that
Speaker 1: any sophistic sufficiently sophisticated system is going to essentially have intelligence,
Speaker 1: though maybe not in a way that matches up directly
Speaker 1: with our our conscious understanding of intelligence. Yeah, I mean
Speaker 1: I think I would adhere to a definition of intelligence
Speaker 1: that is necessarily rooted in some sense of time. And
Speaker 1: this could make sense about why the evolution of intelligent
Speaker 1: minds came about. I mean, as animals needed to move
Speaker 1: faster to do things like our predation theory from the
Speaker 1: Cambrian explosion, you know, as as as the speed of
Speaker 1: life went up, was the need for intelligence increased? Well,
Speaker 1: this makes me think about the you said, if it
Speaker 1: takes a thousand years for you to solve a problem,
Speaker 1: is it intelligence. A lot of that would would I think,
Speaker 1: be relative to the life span of the creature. Right
Speaker 1: and with the human example culture, So for a human being,
Speaker 1: if a human being spends a lifetime solving a sufficiently
Speaker 1: important problem, then it's considered a success. If if if
Speaker 1: if the scientist spends their entire career developing a cure
Speaker 1: for a terrible illness and they find it, they crack
Speaker 1: that nut, then that's a success. Uh. But if you
Speaker 1: look at it for more like a ancient humanoid situation,
Speaker 1: then you could say, well, if a problem isn't solved
Speaker 1: in you know, a day or two, then are you
Speaker 1: really solving the problem because the the challenges are that
Speaker 1: much more immediate, right And then if you're not a human,
Speaker 1: if you're if you're an aunt, if you're if you're
Speaker 1: a cat or a dog, then it seems like everything
Speaker 1: would be well, it would be at least as immediate.
Speaker 1: I mean, essentially, what I'm building up to here is
Speaker 1: that it makes me think that the development of human intelligence,
Speaker 1: or not human intelligence specifically animal intelligence, is link to
Speaker 1: the fast moving demands of right now, like the fact
Speaker 1: that decisions that need to be made quickly will strongly
Speaker 1: affect your survival is what powers the development of problem
Speaker 1: solving acceleration, which is what intelligence could be. Yeah, and
Speaker 1: a lot of this, of course involves not only memory,
Speaker 1: remembering what has come before, but being able to extrapolate
Speaker 1: possible outcomes to engage in in mental time travel or chronesthesia, uh,
Speaker 1: the idea where you can you can think about what
Speaker 1: might happen if you do this, what might happen if
Speaker 1: you do that? You essentially run through various simulations in
Speaker 1: your mind without even necessarily, you know, consciously engaging in
Speaker 1: the exercise. You're you're running the simulations, and it is
Speaker 1: a remarkable to what extent we can run those simulations,
Speaker 1: you know. It's the it's the same sort of energy
Speaker 1: that that enables us to envision the far future of humanity,
Speaker 1: whether it actually matches up with realistic expectations are not.
Speaker 1: This is one of the many things about us that
Speaker 1: I think we take for granted and we don't stop
Speaker 1: to think how weird and amazing it is that we
Speaker 1: can travel through time mentally forward and backward, and that
Speaker 1: we can we can construct events that have not yet
Speaker 1: happened out of events that happened in the past, and
Speaker 1: are not before us right now. I mean, just just
Speaker 1: pay attention to your dog, and then you can appreciate
Speaker 1: how amazing this skill is because your dog doesn't really
Speaker 1: seem to have much of this might have a little
Speaker 1: inkling of it, but it's not robust in the way
Speaker 1: yours is. And you should be thankful. Yeah, yeah, that
Speaker 1: dogs and cats, animals in general, they live in the moment,
Speaker 1: and uh, and there's a lot. I think there's a
Speaker 1: lot to be learned from them. Someone argue that we
Speaker 1: that's one of the greatest gifts that they they bestow
Speaker 1: upon us, is that they allow us to connect with
Speaker 1: the moment. Yeah. I mean, it's hard to rival the
Speaker 1: joy of a dog getting ready to go on a walk.
Speaker 1: Like I often think this. It happens every day. I'm
Speaker 1: gonna take Charlie out. He's gonna poop in the leaves.
Speaker 1: He's gonna smell a bunch of thorns and get stuck
Speaker 1: on the face. And I've just never in my life
Speaker 1: been as happy about anything as he is about the
Speaker 1: fact that he gets to go poop in some leaves.
Speaker 1: All right, On that note, we should probably take a
Speaker 1: break and when we get back, we'll get more into
Speaker 1: the physics of time, and then now all right, we're back.
Speaker 1: So we talk about this present moment a lot, but
Speaker 1: but what is a moment? A very brief period of
Speaker 1: time that's generally that the the definition that you run across. Yeah,
Speaker 1: it's hard to think about this once you start getting
Speaker 1: picky about the geometry of time. So if you imagine
Speaker 1: time as a space that you can map, and the
Speaker 1: moment is maybe like a point along a timeline geometrically
Speaker 1: a point, you know, it does not have like a length.
Speaker 1: It is a point, right, it is it is of
Speaker 1: infinite thinness. And time can't really be like that or
Speaker 1: it wouldn't have any content, right, it would need to
Speaker 1: have some kind of content. So what is the length
Speaker 1: of a moment of time? And if there is a
Speaker 1: length of it, does it not just become a segment
Speaker 1: of time, in which case it's not really a moment
Speaker 1: but a memory. Right. So you know, obviously we have seconds,
Speaker 1: we have microseconds, and we have many different levels of
Speaker 1: division beyond that, which I'm not going to list, but
Speaker 1: you can you can look them up. There's some excellent
Speaker 1: charts that that break down all the crazy variations of seconds.
Speaker 1: Robert take me all the way down. That take me
Speaker 1: turtles all the way down to the bottom of time.
Speaker 1: Is there is there a smallest indivisible unit. Well, in physics,
Speaker 1: we have the plank time. Uh, this is the time
Speaker 1: required for light to travel in a vacuum a distance
Speaker 1: of one plank length. That's essentially we're talking about five
Speaker 1: point thirty nine times ten to the negative forty four
Speaker 1: power seconds. That's a very short time. Yeah, it's in fact,
Speaker 1: it's too fast for scientific observation, as it is dozens
Speaker 1: of orders of magnitude faster than anything we can observe.
Speaker 1: So you might ask yourself, well, is that the now
Speaker 1: if we can't really break it down any further, that
Speaker 1: that has to be there now? Right? Is that the
Speaker 1: thing that time is made off? Sometimes I think you
Speaker 1: see in like popular science articles that the plank time
Speaker 1: gets brought up as like, oh, it is the fundamental
Speaker 1: unit of time. It is the smallest indivisible unit. But
Speaker 1: that's not really how it is. I mean, I don't
Speaker 1: want to try to speak with too much authority. I'm
Speaker 1: not a physicist on this level, but my understanding is
Speaker 1: that plank time is not a fundamental indivisible unit. Of time,
Speaker 1: but that it's the smallest measurement of time that really
Speaker 1: makes sense within our dimensions theory, you know, within the
Speaker 1: way we conceive of physics in the universe, and that
Speaker 1: once you start dealing with smaller units of time you
Speaker 1: can't do any meaningful calculations. Doesn't really mean that there
Speaker 1: aren't smaller measurements of time, just that smaller measurements of
Speaker 1: time would not be meaningful in our physics. Yeah, that
Speaker 1: the briefest physically meaningful span of time. It makes me
Speaker 1: think of what I like to think of as crumb theory.
Speaker 1: With with my son, he's gotten out of this, but
Speaker 1: there was a period of time where he would eat
Speaker 1: something on his plate there was a little bit crumbly,
Speaker 1: and then he would want more of it. But it's
Speaker 1: it's almost like he could not see all the crumbs
Speaker 1: that could be scooped together to make another, you know, spoonful,
Speaker 1: another mouthful or two of the thing he wanted more of.
Speaker 1: It's like those the crumbs were just too small to consider.
Speaker 1: But you know, you, with a little bit of training,
Speaker 1: you could make him see the crumbs within crumbs within crumbs. Yeah,
Speaker 1: and I think he's getting there, but for a while,
Speaker 1: it's like, I want another brownie. We'll how about all
Speaker 1: those crumbs of brownie. I'm sorry, but those are not
Speaker 1: significant quantities of brownie for me to think about. So
Speaker 1: if you can't find a unit of now, that does
Speaker 1: kind of undermine the concept that there is such a
Speaker 1: thing as a now in the universe, you know, uh,
Speaker 1: if it's all kind of these arbitrary units based on
Speaker 1: our our ability to measure things in our physics and
Speaker 1: our mathematical concepts the right. Yeah, but there remains this this,
Speaker 1: this other question too that let's just say that now
Speaker 1: is something that can't be really narrowed down to a
Speaker 1: particular piece of time, but but it's there. Well, then
Speaker 1: is it there for you and me? Is there? Are
Speaker 1: we sharing the same now? It would it would seem
Speaker 1: to just in our experience, right, I am in the
Speaker 1: same room with you right now. Someone else is in
Speaker 1: a room on the other side of the planet, and
Speaker 1: we are in the same now, right. It makes sense.
Speaker 1: But it certainly does. Because let's say you called the
Speaker 1: other side of the planet with the telephone and somebody
Speaker 1: answered the phone. You're both talking on the phone right now, right, Yeah,
Speaker 1: So there does appear to be some very basic sense
Speaker 1: of now that is meaningful. But it's not as simple
Speaker 1: as that seems, right. And to break this down, we're
Speaker 1: gonna have to to board the train of simultaneity. Oh boy,
Speaker 1: So trains come up a lot in considerations of space time.
Speaker 1: For instance, there's the idea that you could have a
Speaker 1: clock measurements made by two people, one on the ground
Speaker 1: and one on a train nearing the speed of light.
Speaker 1: Speed affects the passage of time on each person's wristwatch.
Speaker 1: That's an example of one train thought experiment, but another
Speaker 1: important one, and this is one that you see highlighted
Speaker 1: time and time again. Falk mentions that other writers have
Speaker 1: mentioned it because it is it is a central sort
Speaker 1: of physics of time, philosophy of time, uh thought experiment,
Speaker 1: and this one is used to illustrate the relativity of simultaneity.
Speaker 1: So you're probably wondering what can thought experiments about simultaneous
Speaker 1: events reveal about the nature of now. Well more than
Speaker 1: you might think. In fact, I would just want to
Speaker 1: point out for anybody who's like thought experiments, I don't
Speaker 1: want to get caught up in that philosophical junk. Thought
Speaker 1: experiments have powered some of the greatest revolutions in physics
Speaker 1: and the twentieth century. Einstein's breakthrough his relativity was thought
Speaker 1: experiments before it was proven experimentally, and now it is
Speaker 1: proven experimentally. But so based on relativity, we'll go to
Speaker 1: this thought experiment. Imagine you are standing in the middle
Speaker 1: of a train car. You're right in the middle, and
Speaker 1: you're holding a camera flash. And at each end of
Speaker 1: the car, the front of the car and the back
Speaker 1: of the car, there is another camera flash that's triggered
Speaker 1: by a light sensitive photo diode. And this is a
Speaker 1: thing that converts a light into an electric current. So
Speaker 1: if light strikes either of these sensors on the front
Speaker 1: of the car or the back of the car, the
Speaker 1: flashes they're attached to will go off. And if you
Speaker 1: were to shine a flashlight at just the front of
Speaker 1: the car sensor, that flash would go off, and vice versa.
Speaker 1: I remember you were standing in exactly the middle of
Speaker 1: the car, the exact halfway point between the front flash
Speaker 1: and the back flash, and you're holding this camera flash
Speaker 1: of your own. So let's say you set off the flash.
Speaker 1: What happens, Well, the sensors at the front and the
Speaker 1: back of the car detect that light at exactly the
Speaker 1: same time because you're equidistant from both of them, and
Speaker 1: they both flash simultaneously. And this is all good, right,
Speaker 1: But of course, what happens when you accelerate this train
Speaker 1: to close to the speed of light, which you must
Speaker 1: do in a in a proper train thought experiment light
Speaker 1: speed train. Yeah, so again, we position ourselves in the
Speaker 1: exact center of the car. We're traveling at almost the
Speaker 1: speed of light on top of this train, and then
Speaker 1: we set off our flash, so the photo diodes register
Speaker 1: the light and we experience the two resulting flashes as
Speaker 1: simultaneous occurrences. They occur now, So it's exactly the same
Speaker 1: whether your train car is standing still or moving near
Speaker 1: the speed of light. When you're in the car and
Speaker 1: you set off the flash in the middle, you experience
Speaker 1: the front flash and the back flash going off at
Speaker 1: exactly the same time, even if the car is traveling
Speaker 1: at you know, of the speed of light, and you
Speaker 1: might be thinking like, wait a minute, why is that?
Speaker 1: How can how can that be true if the car
Speaker 1: is moving so fast. Well, it's because we know from
Speaker 1: relativity the speed of light is constant for all observers
Speaker 1: the speed of light in a back and this could
Speaker 1: be complicated by if you imagine like air and stuff
Speaker 1: in the car. But let's just say there's a vacuum
Speaker 1: speed of light, and a vacuum is constant for all observers,
Speaker 1: so the flashes at the front of the car in
Speaker 1: the back of the car would go off at the
Speaker 1: exact same time. But here's where it gets really weird.
Speaker 1: Imagine an observer on the train platform as your hyperspace
Speaker 1: train goes by the speed of light, and there that
Speaker 1: that observer is able to watch what's going on in
Speaker 1: the car at the same time that you are doing it.
Speaker 1: This person would see something completely different than what you're seeing. Yeah,
Speaker 1: to their eyes. The flash in our hands at the
Speaker 1: middle of the train triggers the rear flash first and
Speaker 1: the frontal flash second, So two simultaneous events are no
Speaker 1: longer seen is simultaneous from the outside, Two events happening
Speaker 1: in the now are in separate. Now's yes, and this
Speaker 1: is the weirdness of the world we live in, and
Speaker 1: relativety proves it. The speed of light is constant for
Speaker 1: all observers, so the person in the light speed train
Speaker 1: car experiences both flashes at the same time, the light
Speaker 1: has to travel the same distance to each one. Meanwhile,
Speaker 1: this outside observer sees the sensor at the back of
Speaker 1: the train car essentially chasing the light from the flash
Speaker 1: in your hand. The cars moving really fast, and that
Speaker 1: back of the car sensor is chasing the flash to
Speaker 1: catch up with it. Meanwhile, the censor at the front
Speaker 1: of the train car is essentially running away from the
Speaker 1: flash at nearly the speed of light, so the light
Speaker 1: takes much longer to reach it. And this is not
Speaker 1: some trick of perception for the outside observer. The light
Speaker 1: at the back of the train car actually does go
Speaker 1: off first, even though they still go off simultaneously for
Speaker 1: you inside the train car. Yeah, that is That is
Speaker 1: crazy to to try and wrap one's head around. Yeah,
Speaker 1: but this is the truth of relativity. There is no
Speaker 1: now except for maybe your own personal now. There is
Speaker 1: no universal now. There's no now that is also now
Speaker 1: somewhere far away, and according to Falk, it gets worse. Uh.
Speaker 1: This is one final quote from him here, I think
Speaker 1: says quote, what do we mean when we say a
Speaker 1: particular event is happening now? When we use the word now,
Speaker 1: we are really comparing two events, I can snap my
Speaker 1: fingers and then ask whether some other event is simultaneous
Speaker 1: with my fingers snapping or not. If it is, I
Speaker 1: say that the the event is happening now in the
Speaker 1: Newtonian universe, I can legitimately ask what events in the
Speaker 1: universe are happening right now. The answer would be a
Speaker 1: unique set of occurrence is scattered throughout space, but lying
Speaker 1: on a single slice of time, I can snap my
Speaker 1: fingers and say, at say noon Eastern Standard time in
Speaker 1: December first, two thousand nine, and every event everywhere in
Speaker 1: the universe either is simultaneous with my finger snapping or
Speaker 1: it is not. That was fine for Newton, but not
Speaker 1: for Einstein. As we have seen in special relativity, there
Speaker 1: is no universal agreement among observers as to whether two
Speaker 1: events actually are simultaneous or not, and thus there can
Speaker 1: be no universe personal now. So no now, no now
Speaker 1: for anybody. And this is not a like a time
Speaker 1: zone differential here, well, no hold on. I would say
Speaker 1: that this doesn't mean there is no now for anybody.
Speaker 1: There's no now for anybody. That's also now for anybody else. Uh,
Speaker 1: though in many cases your nows are going to be
Speaker 1: close enough together that it's fine for everyday purposes, Like
Speaker 1: you're gonna be able to coordinate now is pretty well
Speaker 1: with the people around you. But this is not a
Speaker 1: feature of the universe. This is just like a close
Speaker 1: enough approximation that it doesn't matter, right, But I mean
Speaker 1: with enough space, uh, enough distance between people, if we
Speaker 1: were to reach such a point, or or indeed, if
Speaker 1: there are other intelligent life forms that are perceiving time
Speaker 1: in another world, my now could be in their future
Speaker 1: or in their past or vice versa. Yeah, and think
Speaker 1: about this from this kind of science fiction standpoint. So
Speaker 1: we use the concept of now in our politics. For example,
Speaker 1: you know, it's very important that everybody has the election
Speaker 1: at the same now. Right. You can't have the election
Speaker 1: one day for one group and then you know, next
Speaker 1: year for another group and still function properly, right, So
Speaker 1: you need to be able to coordinate events temporally in
Speaker 1: order to get a polity working as it should. But
Speaker 1: try to imagine an interstellar civilization doing something like this.
Speaker 1: And this is one of the questions that I think
Speaker 1: sort of gets overlooked, and a lot of science fiction
Speaker 1: imaginings of interstellar civilization spread out across vast distances of
Speaker 1: the universe. Is the way that the ability of these
Speaker 1: uh you know, top down administrative controls would really be
Speaker 1: utterly crippled by the time differences that essentially by the
Speaker 1: lack of a consensus now between all of the people
Speaker 1: within their control. Yeah. This this is something that came
Speaker 1: up in our the episode We Christian and I did
Speaker 1: a while back about Interplanetary War that there have been
Speaker 1: people who have commented that you could not have an
Speaker 1: inter interstellar empire like you see in Dune or Star Wars,
Speaker 1: or or Star Trek if you want to call those,
Speaker 1: I guess they're empires in some cases because you could
Speaker 1: not maintain order over such vast distances. I wouldn't say
Speaker 1: necessarily that you couldn't maintain order, but that it would
Speaker 1: be extremely difficult to maintain organization. Yes, I would say instead,
Speaker 1: what you could maybe do is maintain order in a
Speaker 1: very brutal way. And maybe this actually explains the brutality
Speaker 1: of the empire in Star Wars, because this is the
Speaker 1: galactic empire, right, It's spanning hundreds of thousands of light years. Uh,
Speaker 1: you essentially have to just be able to whip everybody
Speaker 1: in line the moment you show up, because you can't
Speaker 1: keep them on schedule of normal political uh obedience. It
Speaker 1: does make me think of of actual terrestrial models of
Speaker 1: empire though, like particularly when you look at at at
Speaker 1: the history of China, Like what was one of the
Speaker 1: factors that enabled such such such excellent um unification of
Speaker 1: of different people's And one of them is measurements. It's
Speaker 1: it's making sure everybody's using the same measurements than the
Speaker 1: same currency. Right, And if you write, if you've got
Speaker 1: like a coin that's supposed to have the same value
Speaker 1: at different sides of the empire, but they've got different
Speaker 1: amounts of gold in them, that might be a problem. Right,
Speaker 1: it's also worth noting, um this would you'd have to
Speaker 1: I think we'd have to do more studied early pieces apart.
Speaker 1: But if you go to China, all one time zone.
Speaker 1: There is one time zone in China, uh, no matter
Speaker 1: which end of the country you are on. All right,
Speaker 1: So we're gonna take one more break and when we
Speaker 1: come back, we will jump back into the physics of now. Alright,
Speaker 1: we're back. So I wanted to mention just a couple
Speaker 1: more interesting ideas from physicists physicists about the way in
Speaker 1: which time is conceived for the individual and about the
Speaker 1: experience of now. So there's a book by the Dartmouth
Speaker 1: physicists Marcello Glyzer called The Island of Knowledge, The Limits
Speaker 1: of Science and the Search for Meaning. And I think
Speaker 1: Glyzer makes a kind of interesting point about our concept
Speaker 1: of the present. Of course, as we've established so far,
Speaker 1: the present is not a description of anything that exists
Speaker 1: in reality. It's merely an impression created by our brains.
Speaker 1: But one of the things he highlights is that the
Speaker 1: our impression of the present, at least the thing that
Speaker 1: feels like the present to us, even if there is
Speaker 1: no universal simultaneity, even that thing has clear physical limits.
Speaker 1: And he ends up describing this concept known as the
Speaker 1: sphere of now. So here's an example. What are you
Speaker 1: looking at right now, not a few seconds ago, but
Speaker 1: right this minute? You know, if you're if you're like
Speaker 1: many of our listeners, I would bet it's either a
Speaker 1: car in front of you in traffic, a person sitting
Speaker 1: across from you on the train, or some people ahead
Speaker 1: of you on the next row of treadmills. Okay, so
Speaker 1: I'm wondering whether this is going are we basically getting
Speaker 1: the idea that now is related to proximity? Yeah, exactly.
Speaker 1: Uh so here's my real example, And just imagine instead
Speaker 1: of all that you're looking at a VHS copy of
Speaker 1: Highlander to the quickening I wish. Yeah, you're holding it
Speaker 1: a few feet from your eyes, and uh, whatever this
Speaker 1: thing is, you have to realize in a technical sense
Speaker 1: that you're not really seeing the object as it is now. Now,
Speaker 1: this the time difference here probably doesn't matter enough to
Speaker 1: really make a difference in your life. But the light
Speaker 1: that reflects off the object or emits from it is
Speaker 1: traveling at a speed of about three million meters per second,
Speaker 1: and the light of the light gets absorbed by your
Speaker 1: retina after it bounces off the object, a tiny, tiny
Speaker 1: fraction of a second after the time it leaves the object.
Speaker 1: So if the object you're looking at is within a
Speaker 1: few feet, it's too fast to make much of a
Speaker 1: difference in your behavior or anything like that. But it's
Speaker 1: worth remembering this, and this really does matter over longer distances.
Speaker 1: So imagine you're looking at an object on the moon.
Speaker 1: Once an object is on the moon, even though the
Speaker 1: moon is regularly visible to us, the difference is noticeable.
Speaker 1: So if you say that there are armies of urukai
Speaker 1: standing on the surface of the Moon mooning us, we
Speaker 1: wouldn't see that for about one seconds roughly, because light
Speaker 1: travels at about three thousand kilometers per second, the Moon
Speaker 1: is on average about three eight kilometers away, so it's
Speaker 1: about a second and a quarter delay between the Earth
Speaker 1: and the Moon. And no ordinary matter, energy or information
Speaker 1: can travel faster than the speed of light, And so
Speaker 1: in a sense you can think about the speed of
Speaker 1: light not only is the speed of the photons, but
Speaker 1: really as the speed of causality. I don't know if
Speaker 1: you've heard about this concept before, but that the speed
Speaker 1: of light is sometimes interpreted in the universe is the
Speaker 1: maximum speed at which things can happen, at which a
Speaker 1: thing can affect another thing, meaning that information is in
Speaker 1: some sense traded. Yeah. I think that's that's really good, because,
Speaker 1: especially in sci fi scenarios, we we tend to just
Speaker 1: think of it's easy to just fall into the travel
Speaker 1: of just thinking about speed and travel and movement from
Speaker 1: point A to point B, and not think about breaking
Speaker 1: that down into the simple rate of change and things happening. Yeah,
Speaker 1: and so so think about it. What could happen on
Speaker 1: the Moon to affect the Earth faster than the speed
Speaker 1: of light? I mean, nothing, nothing, and unless you might
Speaker 1: want to invoke some kind of quantum weirdness, but you know,
Speaker 1: nothing on the macro scale. The only thing that comes
Speaker 1: to mind is like cosmic expansion, and I you know,
Speaker 1: I'd kind of have to twist myself in a not
Speaker 1: to come up with a reason for that to occur
Speaker 1: at the Moon, Like it would have to involve like
Speaker 1: galactics showing up or something I don't know. Wouldn't that
Speaker 1: be a great way for the Earth to end? Though?
Speaker 1: I mean, I'm not saying I want the Earth's end.
Speaker 1: I love the Earth. I think the Earth should just
Speaker 1: keep on going. But if it has to end, wouldn't
Speaker 1: it be great if it ends by sudden on expected
Speaker 1: rapid cosmic expansion. We'd never be able to realize it, though, right, Yeah,
Speaker 1: everything just kind of flies apart. It might as well,
Speaker 1: I mean, everybody's life ends, and you might just as
Speaker 1: well assume that that's what occurs. But of course, in
Speaker 1: your moment of now, would you be able to realize that? Yeah?
Speaker 1: I guess. I guess we'll get more into that in
Speaker 1: the next episode. Um, but yeah, I mean we've already
Speaker 1: talked a little bit about the the effects of time dilation,
Speaker 1: of course due to Einstein special and general theories of relativity,
Speaker 1: but those really made it possible for us to understand
Speaker 1: that both speed and gravity cause time to change. Time
Speaker 1: speeds upper slows down relative to outside observers. So you know,
Speaker 1: if you synchronize two watches on earth surface and then
Speaker 1: you take one far out into space, like you take
Speaker 1: it to the Moon, the watch on Earth will run
Speaker 1: slightly slower than the watch on the Moon. And this
Speaker 1: isn't theoretical, this is experimentally proven, not on the Moon,
Speaker 1: but with the surface of Earth and higher altitudes. If
Speaker 1: you doubt that, look up the half Ela keating experiments
Speaker 1: where these a synchronize some precise atomic clocks. Then put
Speaker 1: some in high altitude vehicles or in you know, basically airplanes.
Speaker 1: I don't know why I call them my altitude vehicles.
Speaker 1: Let's just be needlessly confusing. Put them in airplanes flying
Speaker 1: around far from Earth's surface to show that time really
Speaker 1: does pass differently depending on how far you are from
Speaker 1: Earth's large center of gravity. But anyway, Glazer uses all
Speaker 1: this to to talk about this concept he refers to
Speaker 1: as the sphere of now, and he ends up saying
Speaker 1: that the present exists quote because our brain blurs reality.
Speaker 1: That our sense of the present, really, I think for
Speaker 1: him is some kind of like illusion created by the
Speaker 1: brain putting together some elements from different moments of time
Speaker 1: that are within the causality of our sphere of now. Okay,
Speaker 1: I like this. I like this idea of that the
Speaker 1: sphere of now. It's a nice sort of physical, visible
Speaker 1: metaphor that we can employ. One more thing about moments
Speaker 1: in time I wanted to mention was an article from
Speaker 1: October for Nautilus, again with the physicist Max teg Mark
Speaker 1: Mad Max, who is great for exploring all kinds of
Speaker 1: weird corners of physics, uh and strange hypothetical Some would
Speaker 1: say nonsense, others would say ambitious, ambitious trains of thought. Um.
Speaker 1: But he comes up with trying a picture. Essentially, he's
Speaker 1: trying to create a model for what space time looks like.
Speaker 1: And I think he's not the first person to imagine
Speaker 1: things like this. Stephen Hawking sort of tried to imagine
Speaker 1: things like this, but essentially he said, try to picture
Speaker 1: the three dimensions of space that we live in collapse
Speaker 1: down to the form of a two dimensional snapshot, like
Speaker 1: a you know, a photograph. And let's say you've got
Speaker 1: a little square polaroid of the Earth in the Moon
Speaker 1: taken from a point in space above the North Pole.
Speaker 1: And you take one photo, and you see the Earth
Speaker 1: is in the center and the Moon is at one
Speaker 1: spot in its orbit. And then you take another photo
Speaker 1: and the Moon is a little bit further along in
Speaker 1: its orbit. And no, imagine you just keep taking these
Speaker 1: polaroids continuously as fast as you could possibly take them,
Speaker 1: and then you stack them on top of each other
Speaker 1: sequentially to form a tower. Now the height of the
Speaker 1: tower of polaroids here has become the dimension of time.
Speaker 1: Now imagine all these photos not as individual photos, but
Speaker 1: integrated together into a three D image. And what you
Speaker 1: would sort of get out of this when you imagine
Speaker 1: the Earth and the Moon images stacked sequentially, is you
Speaker 1: would get a cylinder of the Earth passing through the
Speaker 1: middle of this box, and then a spiraling corkscrew of
Speaker 1: the Moon going all all the way around it, over
Speaker 1: and over again. And this is a way he comes
Speaker 1: up with of of picturing for d spacetime. Now, this
Speaker 1: is the interesting thing, he says. Try to imagine all
Speaker 1: the elementary particles in your body this way, like they
Speaker 1: begin to accumulate in this box, Like all these strands
Speaker 1: start coming together around the time of your conception. And
Speaker 1: as the elementary particles in your body move around, as
Speaker 1: blood cells ring around your circulatory system, as your nervous
Speaker 1: system passes around sodium and calcium and potassium ions, all
Speaker 1: of these complex interactions make the shape of this immensely
Speaker 1: complex braid in your time tower. And every time you eat,
Speaker 1: and every time you breathe, every time you eliminate waste,
Speaker 1: new strands and little hairs get pulled into this braid
Speaker 1: or go out from it. And at the end of
Speaker 1: your life, of course, the braid unravels and the strands
Speaker 1: all go their own way. I've never really heard it
Speaker 1: put this way before that he's not the first to
Speaker 1: imagine a sort of block of space time like this,
Speaker 1: but he's the first I've ever heard describe it as
Speaker 1: a braid of particles through time. And I think that's
Speaker 1: just beautiful. Yeah, it does seem far more in keeping
Speaker 1: with it just the complexity of of time, as as
Speaker 1: we are discussing it here when we start drawing in
Speaker 1: these these physical understandings of what's occurring. But of course
Speaker 1: if you look at this image, you have to say, okay,
Speaker 1: what then is the moment? Is their room for now
Speaker 1: in this image? If there is, there's only a metaphorical
Speaker 1: one that's been created here in this h this image
Speaker 1: we've come up with, it's not really analogous exactly to reality.
Speaker 1: But what you'd have to picture is sort of a
Speaker 1: not right that the now has become just this tangle
Speaker 1: that can't really be understood. It's a cross section that
Speaker 1: can't be understood without all of the braid before it
Speaker 1: and after it. Isn't that perfect though, This thing that
Speaker 1: is so easy to dismiss as this, this single point, this,
Speaker 1: this smallest common denominator, is actually this enormous tangle of complexity. Yeah,
Speaker 1: and tech Mark even says quote some people find it
Speaker 1: emotionally displeasing to think of themselves as a collection of particles.
Speaker 1: I got a good laugh back in my twenties when
Speaker 1: my friend Amile addressed my friend Matt's as an atom
Speaker 1: hoge Swedish for adam heap Uh in an attempt to
Speaker 1: insult him. However, if someone says I can't believe I'm
Speaker 1: just a heap of atoms, I object to the use
Speaker 1: of the word. Just The elaborate spacetime braid that corresponds
Speaker 1: to their mind is hands down the most beautifully complex
Speaker 1: type of pattern we've ever encountered in our universe. The
Speaker 1: world's fastest computer, the Grand Canyon, or even the Sun,
Speaker 1: their spacetime patterns are all simple in comparison. In other words,
Speaker 1: there's no braid like life. So I guess that's probably
Speaker 1: gonna wrap it up for today's episode, but we will
Speaker 1: come back next time because I feel like we haven't
Speaker 1: gotten to the bottom of this question that we've sort
Speaker 1: of discussed. How there is no external or objective now.
Speaker 1: There's no now from the perspective of the universe that
Speaker 1: really makes any sense to talk about, and yet there
Speaker 1: very much is a sense of now that feels like
Speaker 1: it makes sense in our lives. So what is that now?
Speaker 1: What's going on in our brains when we conceive of
Speaker 1: the now? And I think that's what we will explore
Speaker 1: next time. Yeah, join us as we we look at
Speaker 1: the philosophy of now, as well as the psychology and
Speaker 1: Neuroscience of the now M. In the meantime, be sure
Speaker 1: to check out all our other episodes. That's Stuff to
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