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What does “exist” mean in physics?

What does “exist” mean in physics? 
there is something associated with a physical quantity that describes a theory (principles and laws) which is already validated by the experiments. - Quora


What does “exist” mean in physics? In my thinking, the term “exist” in physics means there is something associated with a physical quantity that describes a theory (principles and laws) which is already validated by the experiments.
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Alan Cooper
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The term “exist” doesn’t really exist in physics per se (though it may be popular among philosophers and “interpreters” of physics).

In the community of physicists, just as in the world at large, the claim that something exists is, I think, generally taken to imply that the thing in question is being identified with a phenomenon that is, in principle, apparent to any rational entity that is in a position to observe it. So, for example the existence of pain from my tooth cannot be denied by anyone other than either myself or someone with a way of detecting nerve impulses from that tooth to my brain; but the existence of the garden gnome that I (think I) see sitting on the couch in my living room can be denied (or confirmed) by any other (rational) person in the room.

The idea that “there is something associated with a physical quantity that describes a theory (principles and laws) which is already validated by the experiments” is too vague to be useful (and certainly is wrong because of the “already validated” condition, as several answers have already pointed out).

The claim of existence of photons, for example, is a popular way of expressing the fact that energy exchanges between the electromagnetic field and other entities appear to occur in discrete chunks or “quanta”. Since this is something that could in principle have been observed by anyone who performed the relevant experiment (including before the time when it was actually done), it is generally understood that photons “exist” (and have always existed), as units of such energy exchange, at the particular point in time and space where the exchange is (or could be) observed to happen. But it is a misunderstanding of the theory to infer that in between such events the photon “exists” as something that travels a well-defined trajectory between them.

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Anil Mitra
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Originally Answered: What does “exist” means in physics? 
In my thinking, the term “exist” in physics means something exists, which is associated with a physical quantity that describes a theory (principle and law) that is already validated by the experiments.
‘Particle’, ‘field’, ‘mass’, ‘momentum’, ‘space’, ‘time’… are some terms used in physical theories of the cosmos.

‘Exist’ is not a term used in the theories.

But in ordinary English to say something exists is to assert that there is such a thing. “I exist” means “I am”. If you get into philosophy, what ‘exists’ means, depends on one’s philosophical approach. Materialists think matter is the only ‘real’ kind of thing, so for materialists, something exists if it is material—which makes for a problem when a materialist asks whether ideas are real (I am not implying that the problem is insoluble). 

Idealists think, roughly, that ideas, e.g., percepts, concepts, feelings, are the true reals. Existentialists may argue that existence itself is most fundamental—for them, something is real “if it is there” and is not to be measured in terms of—reduced to—matter or mind (they are not saying matter or mind are not real but that what they are is secondary to existence). I like that aspect of existentialism because it keeps things simple. However, the question remains—can we build up a true picture of the world based on existentialism? That is a project in philosophy (I hold that it can be done but to attempt to explain how to do so right here would not help answer the question).

So there are three approaches I suggest in explaining what exists means regarding the objects of the theories of physics.

Many physicists take for granted that the entities described in the most successful fundamental theories exist—i.e., they think of quantum and gravitational fields as examples of things that exist.
Other physicists, perhaps a little more philosophical, think, okay, we used to think Newtonian particles were ‘real’, but now our modern theories tell us that they were not really real, so maybe a future physics will tell us that quantum fields are not really real. Such physicists—and philosophers and thinking people generally—may think of the theories as models of reality, of what exists, and leave the question of the true nature of existence open.
Philosophical, for which refer to the third paragraph of this answer.
For a short term, practical answer I prefer #2 (#1 is fine for a practicing physicist, but is not an answer); for a long term ‘true’ answer, I prefer the approach from existentialism but would change my preference when and if a final true and complete physics is developed.

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Brent Meeker
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That’s a good answer and it’s what W.V.O. Quine said. But I think of that as defining what it means to exist in a theory. Of course if the theory is true, then it also defines what exists in reality. But sadly we never know that our theories are true. I like the definition of my later friend Vic Stenger used: “If when you kick it, it kicks back.” That’s not strictly definitive since, as Vic knew, “kicking it” is always in part theory dependent. So from literally kicking a rock to “kicking” a rock with a gamma ray spectrometer is a little further from reality. But it means that mathematical structures like Hilbert space don’t exist; there are too many other mathematically equivalent formulations of quantum mechanics.

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Originally Answered: What does “exist” means in physics? In my thinking, the term “exist” in physics means something exists, which is associated with a physical quantity that describes a theory (principle and law) that is already validated by the experiments.
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I think you’re mixing up ontology with theoretical support.

Before a certain point, nobody had any idea that quarks existed. Then, we knew there was some structure inside hadrons, but had no idea how it could work. A number of speculative theories were deployed, but of course none of them were actual theories validated by experiment. One of those, the quark model, turned out to work—but even then, it was hard to get any new predictions, rather than just retrodictions of known data, until quantum chromodynamics was developed.

So, are you suggesting that quarks did not exist in 1960, and suddenly came into existence (everywhere? only in our labs? in an expanding volume of spacetime about our labs?) once QCD passed enough tests?

Also, I’m not sure what the qualification “associated with a physical quantity” is supposed to mean. You can associate anything with a physical quantity; so what?

And a physical quantity certainly doesn’t describe a theory; it’s the other way around.

And a theory isn’t a principle and law; it’s more an explanation and model, where the explanation fits with neighboring theories and the model has been validated by experiment.

But, again, I don’t think any of this has anything to do with existence, either to a physicist or to a philosopher of science.

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Todd Smith
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Originally Answered: What does “exist” means in physics? In my thinking, the term “exist” in physics means something exists, which is associated with a physical quantity that describes a theory (principle and law) that is already validated by the experiments.

Until the End of Time: Brian Greene in Conversation with Janna Levin


Until the End of Time: Brian Greene in Conversation with Janna Levin

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346,711 views  Apr 23, 2020
Brian Greene, the world-renowned physicist and best-selling author of The Elegant Universe, launches his captivating new book Until the End of Time: Mind, Matter, and Our Search for Meaning in an Evolving Universe at Pioneer Works. Join Janna Levin, our Director of Sciences, in conversation with Brian Greene to grasp and gain a refined appreciation for our fleeting, but utterly exquisite, moment in the cosmos.

This project is supported by Science Sandbox, a Simons Foundation initiative dedicated to engaging everyone with the process of science.
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0:00
[Applause] I'm very excited to introduce my friend
0:08
and colleague and scientific collaborator Brian Greene brian is a
0:16
professor of mathematics and physics and the director of Columbia University's Center for Theoretical Physics and brian
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has made incredibly important contributions to string theory which we'll talk about
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he has many New York Times bestselling books including the elegant universe
0:35
fabric of the cosmos and the hidden reality and now the book we're here to celebrate until the end of time so
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please join me in welcoming Brian Greene
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Brian I often complain that we don't get enough of a chance to talk so I've seen
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you in like three or four years it's great it's ridiculous so we're gonna pretend nobody else is
1:04
here and we're just gonna have like our own little private communion so I do
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want to discuss to begin and I am gonna speak on behalf of the audience for a
1:15
second because I would be remiss not to ask you about your contributions to string theory but string theory in
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general so one of the things I love about what you did with string theory is that your discoveries were unanticipated
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and that's that's like the mark of some creative moment when you make an
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unanticipated discovery and and so in the field in physics you're very known
1:38
for that accomplishment but also in the world for having being a spokesperson
1:45
for this this this model of the world and so I need to ask you on behalf of
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everyone else for a Lightning primer on string theory Oh string theory my goodness so Albert
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Einstein way back in the 1920s 30s 40s 50s dreamed of finding what it called a
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unified theory of physics which would be a single mathematical equation a single
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mathematical sentence if you will that would be able to put together all of nature's forces
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and all matter into a single tight package that would allow us to
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understand the workings of the universe from a very basic starting point and he
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sought this unified theory til the very end there's a famous story that he was
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on his deathbed in Princeton New Jersey in 1955 and was still scribbling
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equations at the very end in the hope that he'd complete the unified theory and he didn't and string theory is our
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hope that we may have it and in a nutshell the new idea is simply that
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instead of the fundamental constituents being little dot particles as we have long thought of them the electrons the
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quarks and neutrinos little tiny dots of no structure the new idea is that they're actually little tiny filaments
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of vibrating energy and the different vibrations of the string like entities
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the different notes if you will that it can play correspond to the different particles making up the world so
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everything is united under the rubric if you will of the music that these strings can play that's the basic idea and it's
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absolutely beautiful in that description really conveys to you why it's so important ly unifying it so here you are
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you're thinking about this incredible unifying idea which really is it's mathematically incredibly challenging
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it's totally profound you're basically saying anything anyone has ever seen or
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ever will see or understand or think about or be is asked or played out on
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the harmonics of these fundamental strings and you lift your head up from the page glaring at these stunning
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equations and you look around and you say what's it all about yeah that's like
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unnerving because we're kind of relying on you have all our introduction we've heard what it's all so you know you
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you're you're bringing us all this sense of meaning and import and in all of your
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previous books and your previous work on string theory and then you're like you're like leaving us on the precipice and you're lifting your head up and
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you're telling us you don't know what it's all about so did you have like an existential crisis what happened you know I think we all should have an
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existential crises sort of all the time I think it's good for the soul but the the motivation for this book was not
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really to say I don't know what the answer is even though I don't really know what the
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answer is but it was to give a certain perspective on the journey toward an
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answer and the perspective I take in this book is one that has gotten a bad
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rap I would say over many decades it's a highly reductionist view of the
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world but at the same time injecting the part of the reductionist program that
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often physicists give short shrift which is the synthesis you need to know what
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things are made of you need to know what the fundamental laws are you need to know the ingredients and how they operate interact and so on but to tell a
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full story you have to understand how the ingredients come together to build the structures of the world be those
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molecules or cells or living beings there's conscious self reflective beings and when you see all of those stories
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nested together in one narrative arc to me it gives a deeper understanding of
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where we came from and what's happening at the moment and ultimately where we're
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going and I think that's vital to the search for trying to understand why it
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is that we're here at all so it very much feels like that it very much feels like a rationalists search
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for meaning and you discuss the sort of many scales of meaning and and having
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sought meaning in physics found it but not found all of it not found all the
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ways in which to understand it what kind of march through some of the things that you describe but there's something else which is kind of the provocation of
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death that you talk about yeah and you write so beautifully you have a line and I'm gonna see if I can render it
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correctly you say and the ledger of birth and death with entries more numerous than stars in the galaxy will
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balance with dispassionate precision in other words we live we die and that will
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always balance and that is such a it's such a beautiful line but the also
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intellectually the motivation of that does that spark some creative motivation
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yeah well I mean I can give my own personal journey toward that perspective
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which is you know way back I guess it must be in the 1980s I encountered a
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book that had a profound impact on me it was a book called the denial of death by Ernest Becker I mean how many people
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have are familiar with that book - yeah one or two yeah it was fantastic
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it's amazing how books that are so well known in one ERA can just sort of
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disappear as you go forward but what Becker was doing was basically channeling the ideas of otto ronk who is
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a early Freud in broke with Freud at some point who as Becker articulated had
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this view that the real motivating force behind us human beings is actually the
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recognition that we are mortal and we really are as far as we can tell the unique species on the planet
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that recognizes that we have these finite life spans and the question is
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what does that do to us and Becker's argument which has now been carefully
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furthered by a whole group of social psychologists is that we try to deny the
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possibility that we can be fully erased from the world we try to leave some kind of legacy it can be a real legacies
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right we we build monuments we build pyramids but it can also be a symbolic legacy where we create creative work or
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we have a family I mean there are many ways in which we feel that we can integrate our existence in a manner that
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will not be wiped out when we are gone and the thing that struck me about that
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idea as I was studying physics alongside of it is the more you study physics you realize that there is a recapitulation
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of the death of the human being at the level of the universe the universe itself had a beginning it has aged it
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matures and if you follow laws of physics in the manner for instance that I described in some detail toward the end of the book there is strong reason
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to believe that there is a sense in which the universe itself will die and so this interplay between the death of
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the universe is described by physics and the death of the individual well known to all of us to me felt like a very fertile place to
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explore yeah you very much open the book and mirror it in the end which is as
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though you're not satisfied with the sense of dread that every human being
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has that is aware of their own death you want to make sure that you're like hanging us off the glass with this
9:16
hollow sense of dread that it will all be gone like the end of everything in
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time and so what the hell's going to want to read this book you know so there's a turn that happens in the now
9:29
that may be worth discussing which is I am quite upbeat about the death of the
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universe look I mean you know we were talking about longevity but there has to
9:39
be an end to life itself I mean nobody wants to live forever I mean there's one of these novels where where the
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character at the end says you know is in heaven for if for ages and says well is
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there an alternative to all this bliss and the joy and the golfing and everything I want and they're like yeah you know this like right over and he
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says does anyone ever take that path and I think it's the angel says everyone yeah right you know there are so many
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works that have explored the possibility of immortality and in the vast majority
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of them it does not turn out very well so it's a it's a deep human wish and
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desire but at the same time when you think it through in some detail it's unclear that it yields the return that
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we can envision but but the point that that I think is really important to
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stress and it's one that I develop as you know from reading the book is that when you recognize that we are the
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product of purposeless mindless laws of physics playing themselves out on our
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particles because we are all bags of particles and think as I mentioned this
10:49
is a line that came out in a Stephen Colbert interview on The Late Show and he shot back immediately that is a great pickup line and it is I
10:58
should tell you feel free to use it at any time but but when you realize that that's all that we are it changes
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the way you search for meaning and purpose you recognize that looking out to the
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cosmos to find some answer that sort of floating out there in the void is just
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facing the wrong direction in the end of the day we have to manufacture our own
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meaning our own purpose we have to manufacture coherence which is what we do as physicist and what artists and
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everybody else in the world does in their everyday lives to try to make sense of existence and when you
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manufacture purpose that doesn't make it artificial that makes it so much more
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noble than accepting purpose that is thrust upon you from the outer world so
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in the end the final story that you're led to from this kind of journey I think is one that is and no bling not one that
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leads you to the darkness and you feel this so much in this journey and so I
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would like everyone just to have the opportunity to kind of start where you start in the book and and how you get to
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this very optimistic telling of you know in some sense the story of our lives
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and you begin with these very austere principles these forces that basically
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carve reality out of the space of possibilities which are dual entropy and
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evolution so let's let's talk about the person because their evolution is a little more familiar to people entropy
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everyone's heard of and uses but is a difficult concept or one destroys one
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builds and does that work together so so the rough description is the one that you describe I think many of us use the
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phrase entropy in everyday life as a description of going from good to bad
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you know order to chaos you know the degradation of structure
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that's the feeling that the notion of entropy and the second law of thermodynamics which describes the
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relentless increase in entropy across the universe throughout time that's what it brings to mind and that's partly true
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but the point that I stress in the book is one that isn't as emphasized as
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perhaps it should be which is even though the universe is on
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to have ever increasing disorder ever increasing entropy there can be the
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forces of nature in fact ensure that pockets of order can form within the
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overall drive to disorder and the pockets that are most prevalent are stars you might ask yourself how in the
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world could stars form if the universe is heading toward disorder there these orderly beautiful structures in the
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heavens how could they ever come to be and a careful discussion of the force of
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gravity and how it talks to this principle of the increase in entropy allows you to conclude that when a star
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forms yes you get order here but in the process it releases so much disorder to
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the environment that on balance the entropy goes up even though order forms
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in a local region of space and it's something I call the entropic to step to
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give you a sense of it's really an entropic dance where the entropy goes down here the entropy goes up in the
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surrounding environment and that's how it's not totally the destruction of
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structures in the world it's actually building up structures so long as in the
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process they yield enough disorder to balance it all out so our friend Sean
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Carroll has said things like when you make an omelet you're taking an ordered egg and making a disordered omelet
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you're doing cosmology because it's a reflection of the fact that the Big Bang began in an incredibly ordered stage
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that's right and so somehow this idea of the second law of thermodynamics the increase of entropy that that is also
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the era of time that our past is ordered our future is disordered we live with
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this great fortune that our past was ordered yes and we don't know why we don't know why and do you think there's
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going to be a resolution to that question why was the past ordered why will you know why are we so fortunate as
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to be able to do the entropic two-step yeah point you're making is absolutely right if the Big Bang itself is highly
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disordered then there wouldn't have been the opportunity for order to form in the
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future because we'd go from incredible disorder to yet more disorder but we began for some reason that remains
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mysterious in a configuration near the Big Bang that itself had very low entropy a lot
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of order and we have been living through in some sense the degradation of that order through cosmological history so
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the question is can we explain where that ordered first configuration of the
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world came from and I don't know I know I've I've written papers on this I I
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don't believe the papers that I've written on them they they felt right at the time but you know you rethink things
16:04
and it's less convincing and and the and the other thing is it's unclear that it's even a question because you know if
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if the use a one way of framing the issue is this when things are highly
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ordered we often think about them as highly unlikely to have randomly arisen
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right you throw all your stuff on your desktop and it will fall in some
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disordered high entropic State because that's the easy way the simple way for
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the ingredients to fall you would be surprised I think if you threw all your
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junk on your desktop and it just happened to be the case that the pens and pencils all went right into the
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holder the pages just landed all in order you know on your desktop that's
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such an unlikely highly ordered state of affairs that you just don't think it
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could possibly happen without a guiding intelligence so could you have a highly ordered beginning to the universe without a guiding intelligence and the
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supposition in there is that a highly ordered Big Bang is itself unlikely just
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like throwing your junk on the desk and getting an order configuration is unlikely but is it really unlikely if
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the Big Bang happened once then there's kind of a hundred percent certainty that it happened as it did right there is no
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other opportunity it's not although you are throwing darts at a wall and where the dart lands determines what the Big
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Bang was like there is simply an event that took place that had certain properties and maybe you just need to accept it for what it was and move
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forward from there well so I want to ask you this said this to you once at Columbia when we were hanging out and you you looked
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at me like I was crazy so a chicken gives birth to an egg not a
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scrambled egg yeah so why you know we understand that as being an execution of
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certain DNA codes and yes overall the entropy increases of the whole larger system yeah but in that process there
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was a code that was executed it was a very prescriptive and made something very ordered actually why can't we think
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the laws of physics that way that when the universe began there were these laws of physics and it created an ordered egg yeah I I don't I if I looked at you like
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you were crazy indigestion or something you know maybe they're reading more into it than it was
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it could well be that the laws of physics themselves when playing out in a
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cosmological setting guarantee that some first event would be highly ordered you
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know giving birth to the universe like giving birth to the egg the problem I have with turning that into a real full
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explanation is I don't see how that happens in our current configuration of
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the laws of physics they tell us about how things evolve over time but they don't tell us the initial conditions so
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is it the case that we could come up with laws that determine the conditions
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as opposed to laws that tell us how the conditions change and that's the part of the story that that feels okay really
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fun this gonna be like a good DeLeon setting its own initial data like awesome good talk about this later
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but then you bring us from the idea of entropy and evolution and evolution you
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haven't really touched upon but you will I think in this next step which is the
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emergence of life so somehow we get from these austere physical laws or principles at least to life and and
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that's a big leap and life is incredibly ordered right and has to do what you're describing which is this kind of
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entropic to stuff so life is somehow maximized or not if not maximizing exploiting the entropic potential of the
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universe yeah so take us to that step of life yeah well I think many of us certainly it was a case for me when I
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first learned about evolution in high school mrs. Goldberg Stuyvesant High
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School remember it was all in the context of the framework within which Darwin and Wallace really wrote their
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initial ideas down which is understanding the great wealth of species on planet Earth and in that
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setting we all know what they told us right in the descent from parent to
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progeny there's descent with modification and those modifications are such that some of the progeny are worse
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at surviving and those are the ones that will be less likely to reproduce some are better at surviving they're the ones
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that are more likely to reproduce and their first spread that particular mutation widely through the genetic pool
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now of course that version of evolution assumes that life already exists a question is does evolution give us any
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insight perhaps into how life itself may have first gotten started and they're
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our versions of natural selection and evolution which haven't developed over
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the decades which do go further back there is a version called molecular Darwinism and molecular Darwinism is a
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kind of evolution of the universe in which you're starting with atoms and particles and you recognize that once
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those atoms learn a very specific trick once they learned how to replicate make
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copies of themselves that's not all that hard if you have a bunch of atoms that are stuck together in a configuration
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and they're very good at drawing in the very same ingredients out of which they are made they can form the template that
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copies that atomic configuration that molecular configuration yielding copies of itself so once a collection of
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molecules learns how to replicate then you're in an interesting situation because if mutations if some copy is not
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identical to the original and if that copy is even better able to make copies of itself it will draw in more of the
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raw material in the environment and dominate the molecular demographics and if in that replication process you
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get another mutation that's even better replicating it will then take over and indeed you can have molecules coming
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together in even more complicated structures and in that way making copies and holding on to information that
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allows them to not only make copies but direct the creation of copies and so
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this idea a kind of chemical combat that is a molecular version of Darwinian
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natural selection maybe how we go from a bath of particles to collections that
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are ever more ordered ever more complicated ultimately taking us to the molecules necessary for life and you say
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life is physics orchestrated it do you you you do not have any illusions of trying to make some magic step yeah you
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very much are a physicalist and a reductionist in that sense you see life is physics orchestrated but no less magical exactly I mean there was a time
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in the 1800s when scientists didn't have that perspective the view was how can
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you make life out of lifeless particles and the answer was you can't you have to
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inject something else the life force has to be put into these particles but as we
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have studied life with ever greater intensity nobody says that any longer no
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scientists say that any longer the recognition is that the laws of physics and the particles of matter coming
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together in the right configurations that kind of choreography allows life to emerge you don't seem to need anything
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but the ingredients and the laws and these processes that put the particles
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together so you're marching us from this completely austere inanimate world of
23:52
these theoretical principles towards a consciousness where life becomes a
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vehicle of consciousness that can reflect and begin to ask these questions reflect on meaning and so it's really at
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this next step when you you you bring in life as a vehicle for consciousness may begin to think about well is
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consciousness exactly the same way is it absolutely reducible to the orchestration of physical particles and
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their relationship that consciousness emerges and there's magic there and this is of course still a very aggressive ongoing debate
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although there are very few people who say it's anything other than yes I mean I mean there's some of course that do
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say that you need more but you're absolutely right I mean the progression is you have living beings that
24:36
ultimately emerge from these processes some of those living beings acquire some degree of conscious self-awareness
24:43
conscious self-reflection and the very same conundrum that for the browser
24:49
scientists in the 1800's comes to the fore here again because you can just articulate the same question but swap
24:57
out some words how can mindless thoughtless particles come together in a
25:02
configuration that somehow yields the inner sensation of thought feeling emotion how can they possibly generate
25:11
that if they themselves don't have any intrinsic version of those conscious
25:17
qualities from the get-go now some people respond much as those in
25:22
the past did with life they say those particles can't create consciousness on their own there has to be something else
25:29
a consciousness field that we somehow tap into or the particles themselves may
25:35
themselves have a little proto conscious quality so the electron might have
25:40
electric charge and mass and quantum mechanical spin david chalmers idea exactly yeah and in addition to the
25:47
properties of particles that we are familiar with maybe they have a little bit of consciousness and when you put a
25:52
lot of them together you got a lot of consciousness and that's what we are my own feeling and there's no proof to this
25:59
but my own feeling is that we are recapitulating the same story with life and that at some point when we fully
26:04
understand or better understand the brain and mind we will no longer invest
26:09
such mystery in the emergence of consciousness we'll look back at these days and kind of quaintly smile at the
26:15
ideas that were put forward and we will recognize as we do with life that consciousness is nothing but particles
26:22
coursing through a gloppy gray in our particular structure head and within that motion those particles generate the
26:30
conscious sensations that we all experience so there is this very interesting
26:37
transition we can think about with consciousness which sort of helps which is the idea that some distant relative
26:43
in the past first developed before consciousness attention this idea of you
26:48
know maybe there was some worm that needed to decide between the heat or the light or the food and began began to
26:57
develop a map of the external world and this idea I think of simplifying or
27:03
making a map of the world is a very interesting attitude towards consciousness because it since we're kind of over inflating it in some sense
27:09
consciousness might be a consequence of our inability to analyze all the data right that there's just too much data
27:16
coming from the outside we can't possibly do it in terms of the number of the frequencies or the exact
27:21
temperatures but so instead we make an approximate map of the external world and that's probably the first step and the next step is a map of the internal
27:28
world yes exactly so so one person has articulated a view like that as Michel
27:34
Graziano Princeton and he has basically stressed the fact that we look out at
27:39
the world we see patterns and we make models of those patterns in order that we can navigate reality but those models
27:46
are always imprecise incomplete and when we take that same idea and apply it
27:53
internal to understand not only say what's happening inside my head but as I look at you right now I'm kind of trying
28:01
to figure out what's happening inside your head - right like am I going on too long you want me to do something you're
28:06
right and these are important things for us to do as a social species so that we can engage in a manner of mind exactly
28:13
another matters I see right and but my map of your mind as well as my map of my
28:18
own mind is incomplete its imprecise and with that imprecision we lose the full
28:24
link to all of the physical processes responsible for conscious sensation
28:29
which is an explanation perhaps for why it is that it feels like that voice up here is floating untethered is floating
28:37
unmoored in our mind the reason it feels unmoored is because we have this imprecise incomplete map of what's going
28:45
on and we leave out the very ingredients that Woodmoor it that would tether it to physical processes and that
28:51
makes it feel so ethereal that we invest it with qualities that may in fact not
28:56
be justified so if we imagine an incredible ai that it's able to do all
29:03
the computations necessary to understand the room in terms of every single bit of data that reaches it would it need to
29:09
develop consciousness would it need to think and feel and have emotions and yeah well need is an interesting
29:14
question what it at all what are you if it doesn't need to with Darwinian adaptation suggest it wouldn't yes so it
29:21
could simply be the case that when you have this kind of complexity and when
29:28
you have a structure able to undertake the kind of information processing that we are familiar with each and every day
29:34
every scene every moment of our lives and maybe that conscious self-awareness
29:40
emerges as a byproduct of that kind of information processing it may simply be
29:47
the case that it has to be that way that it can't be any other way as this is part and parcel of the same
29:54
system and that really leads us to the very thorny concept of free will
30:01
yeah because it's only with consciousness that you begin to reflect on having choices yeah and and you know
30:09
freewill is a is a bitter bitter debate and not a very popular concept anymore
30:15
and I and I do believe that also you are very skeptical about the existence of free will but not totally about the idea
30:22
of freedom so start us with annihilating free will and then we'll think about how to resuscitate some notion of freedom
30:28
yeah well let's throw them a little buoy after we like drown them well about we throw one one buoy first I'm happy to go
30:34
to freewill I love to talk about that subject but even just unconsciousness again to my mind when you describe
30:44
consciousness in the manner that we have just now I don't think that in any way
30:50
diminishes consciousness some I've had these conversations you know I remember
30:55
having an on stage discussion of this sort a couple years ago and when this discussion of
31:01
consciousness happens someone in the back yelled out you're describing hell you know and it's like and I get it
31:08
because if we're used to thinking of consciousness as this pristine spectacular quality that we are endowed
31:16
with from something magical in the external world to frame it in a reductionist way can feel like you're
31:22
flattening it however I think it's utterly spectacular that the very same
31:29
physical processes that are responsible for this picture of water or the structure of this table is what's
31:35
responsible for conscious self-awareness how miraculous that collections of
31:41
particles can do and think and feel what we do that I think is the conclusion it
31:47
amplifies and elevates the wonder of it all it doesn't take away from it now to
31:52
turn to freewill or if you want to know it's the reductionist defense to say it
31:57
does not take the shine off of the experience ya are still conscious we still feel it it doesn't you don't by
32:03
magically analyzing it this way annihilate the experience of feeling right now when it comes to free will
32:09
though I think we do annihilate it you know so it's holding hands and humming you know and and and the
32:17
argument you know I think is is quite straightforward which is if we buy into
32:24
this version of consciousness we recognize that every decision every
32:30
thing that we thought we were the ultimate author of is in fact at the
32:35
level of particles nothing but those particles coursing through our minds going this way or that resulting in us
32:42
saying either yes or no or going left or right and if the motion of those
32:47
particles is nothing but physics articulated in the language of particles
32:53
if there is no place for us to intercede in the mathematical unfolding and I assure you there's no place in the
33:00
fundamental laws of physics where it says keep on chugging along but when you get to this point
33:05
ask ask the person what they want to do at that point you know that there's simply no place for us to insert
33:11
ourselves in the mathematical unfolding of physical law and that being the case there is no justification for the
33:20
intuition that we are the ultimate authors of our actions that we can somehow supersede the strings that are
33:28
pulling us that are governed by the equations of physics so that version of
33:34
free will which is the strongest one that we are fully calling our own shots
33:39
we are the authors of our actions we are autonomous that notion of free will
33:44
seems to be completely incompatible with our understanding of the physical world so this is your line to colbert when you
33:51
said to him you're just a bag of particles controlled by the laws of physics yeah yeah and yet you you do a little about-face
34:00
it's any not an about-face that's not fair to say but you do a little you give us a bone you give us the buoy
34:06
I don't know I'm losing my metaphors but you know this idea that there is still some sense of freedom
34:12
yeah and that we're more complex than Iraq right exactly yeah so so I I don't
34:18
really consider it a bone per se but I understand exactly why you frame it that way but my view is that there is an
34:26
alternative notion of freedom not the freedom of the will that I think we all
34:32
intuitively have and the one that I described the absence of but there's a kind of freedom that we humans have that
34:39
distinguishes us from the inanimate world and the point that you're making Iraq is a good counterpoint rocks can't
34:47
respond in any interesting way to stimuli from the external world we can
34:55
why can we do that not because we have free will in the traditional sense but rather because our arrangement of
35:02
particles is so exquisite compared to the arrangement of particles in Iraq
35:07
that our particles are able to respond in a wealth of different ways to stimuli
35:13
that we receive from the environment so our freedom is not the freedom from the
35:20
tyranny of mathematical laws that doesn't exist instead our freedom
35:26
is a freedom to execute a range of behaviors that are unavailable to the inanimate world we have unshackled our
35:33
behavior through evolutionary development which has allowed us to do things that rocks simply cannot and I
35:41
really do mean that as a substitute not as a bone I truly feel in my bones
35:48
that this resolution is is really satisfying me right now I just
35:54
articulated a sentence how do I view it I say to myself how my particles just
36:00
you know they came together and and they they got that sentence out and I'm
36:05
really pleased that they they did get that sentence out and and and thank goodness for those particles doing you
36:12
know the good thing doing the good work and and and there's a gratification that
36:18
comes with it's a little different from the kind of gratification from free will but I feel responsible for my actions
36:24
because heck it's my particles doing it yeah it's the laws of physics that are guiding at all but who cares
36:30
fundamentally it's me because I am impressing my individuality on what I do because my responses to stimuli are
36:39
highly iconic to me in the particular arrangement of particles in my brain as it is for everybody else now this
36:46
reminds me a little bit of this theory of mind question that you raised earlier you're trying to figure out what I'm
36:52
thinking I'm trying to figure out what you're thinking and I look at you and I don't have a perfect theory of other minds and so to some extent I have to
36:59
attribute to you the kind of freedom that you're describing simply in my uncertainty of being able to reduce to
37:06
the mechanics of the particles and the arrangements and the interactions in your mind because of that I'm left with
37:12
the complexity so vast and a range of options so vast the rock doesn't have that I ascribe to you a sense of freedom
37:18
yes and so I I guess I want to ask you in the same way that you do to yourself for the same reasons and I guess what I
37:24
want to ask you is are you to some extent saying that the illusion of free will is equal to this variety of freedom
37:32
that that we can live with yeah I don't know if I need to equate them
37:38
and I rather would describe them in terms of the role that they play in my
37:45
thought process of how I am in the world and and I I'm I'm willing and feel
37:53
forced to jettison the intuition that I have free will but this other variety of
37:59
freedom feels really good to me so I don't consider them to be the same or equal but this latter version of freedom
38:07
makes it such that I don't pine so much after the old version so you really are
38:13
marching us towards even being able to frame the question of what is the meaning of life to some extent and and
38:22
the next step is really development of language and storytelling yeah in this March and you you reflect on the
38:31
Darwinian explanation possibly of language and you kind of take it and
38:37
leave it and you take it and leave it but I think it's interesting to reflect on a scientific explanation for the
38:44
emergence of language but even more of storytelling yeah and and then doesn't matter if we understand the Darwinian
38:51
explanation yeah or another it's a good question and it all depends on the kinds of mysteries
39:01
that excite you and the kinds of mysteries that you hunger to have an explanation for and one of the mysteries
39:10
that has certainly captured the attention of a community of researches and one that certainly has captured my
39:16
attention is why in the world after we developed language and there many
39:22
theories of where language comes from and as you discuss I described a number of them in the book but there is
39:29
reasonable evidence that language has evolutionary utility right we are able
39:36
to communicate we can coordinate actions we can do things more effectively as a group if we can speak to each other and
39:41
communicate so imagine that language plays that role but after we have language why in the world would we start
39:49
getting together and telling each other fictional tales of non-existent beings in realms that
39:56
have no relevance to the real world why would we spend time doing that that's an
40:01
interesting question to explore yes a storytelling it's really is really the country you and fictional storytelling
40:08
in particular but you know it strikes you as why wouldn't they go out and sharpen some Spears as opposed to talk
40:15
about demigods you mean why wouldn't they gather more fruit and nuts as opposed to you know spending all this
40:21
time we're both members of the conversation know what they're talking about is utterly false from the
40:28
perspective of alignment with things in the outer world and do you feel compelled by a adaptive explanation III
40:34
do I mean it's highly controversial and you're entering a realm where people can
40:40
make up all sorts of just-so stories that you need to be skeptical of because
40:47
you're entering a realm where it's not as though we can go back and think and
40:52
interview those folks who are telling the first tales and figure out why it is that they were doing what they were
40:59
doing but nevertheless there is an interesting idea that researchers have developed that storytelling prepares us
41:06
for challenges in the real world in a very safe way much as ethology right you know play among animals widely
41:13
documented as rehearsing practicing for encounters in the real world right some
41:19
plays very rough hopefully the animals don't get hurt but they're preparing themselves it appears to be the case so
41:25
that when they're in a real fight out there in the world world they have practiced certain kinds of moves and
41:32
responses we may do the same thing with fictional storytelling we may enter a
41:39
whole realm of distinct worlds and encounter a realm with distinct
41:45
personalities and deal with a whole range of distinct challenges and problems all from the safety of
41:52
storytelling as opposed to going out in the dangerous world and having to encounter these situations in order to
42:00
gain the practice and expertise in nuance in response that story to can give us it's kind of like
42:05
theoretical physics versus experimental physics thank you so yeah yeah you see math allows us to commune with other
42:13
realities and language and storytelling allows us to commune with other minds
42:18
yes I'm the deepest way for us to get inside the head of another and they know
42:23
another way of saying it is this you know if you imagined a group of
42:28
individuals say you know some other species of human I'm a human I'm Foreman
42:34
on planet Earth and imagine that they were completely rational I mean maybe in the in the Vulcan sense if you don't
42:40
mind me invoking you know an old Star Trek you know trope so imagine you have these individuals and all they ever do
42:46
is the sensible thing right they never tell fictional accounts waste of time
42:51
they go out they get the food they sharpen the spears and so forth now you know if they were in competition with
42:57
individuals like us who do these wild things where we make up ideas and we
43:02
pursue these crazy which do you think well which would be the better dinner
43:08
companion right you know you have the Vulcan over and all they're talking about is the molecules and atoms and the
43:14
tape and you're like I'm not going to invite that person again right you know but in terms of competition between the
43:19
two I think it's clear that innovation ingenuity surprise discovery is going to
43:25
be the purview of the species like us and I think we ultimately would triumph
43:32
in that kind of a competition so yes could there be could there be I'm not saying that there is could there be an
43:38
evolutionary basis for this kind of behavior I think the answer is possibly yes you also invoke Tony Morrison and
43:46
connecting an idea that you open the book with with this bringing it to the
43:51
point of thinking about language where Tony Morrison says we die that might be the meaning of life but we do language
43:58
that might be the measure of our lives yeah I mean it's really with language that we can articulate a vision of the
44:05
world that is so much richer than the mere facts of existence and you know
44:13
people have taken these ideas in different directions right victims and had this notion that language might
44:19
actually set the border limits yeah the limits and and nobody knew what he was talking about well actually
44:25
you're the expert on this talk about this you know again correct me if I'm
44:30
wrong but that always struck me at least in the naive interpretation as a very
44:36
limited perspective on the nature of reality and nature of truth there are so many things in the world that I feel
44:44
like I engage with that I understand to some degree that I don't have any means
44:49
of articulating in language in fact the number of times that I have felt like if only would there was a word for that but
44:57
there is no word for that and it resolves itself in a different way in my
45:04
understanding so just in defense of Vick and Stein who really should not be defended just cuz
45:09
he was such a nut but you know he he said he was talk about the limits of language and as he said the rest should
45:15
be passed over in silence to that effect but I always interpreted Vic and Stein as saying it just cause something
45:22
actually closer to what you're saying because he said the limits of language are the limits of my world but I I think
45:27
really ultimately he was seeing something else that there was like this negative space almost that he fell into
45:33
to experience something beyond that that that could not be summed up by language
45:38
but also the beauty of Vic and Stein is we can project whatever we want right on top and so there's another quote that
45:45
you raised in which also connects this idea of railing against mortality which is just really motivating force in your
45:52
book is one of Shakespeare's and I'm gonna see if I can get this one right he
45:57
says when all the breathers of this world are dead you still shall live such
46:03
as such virtue has my power yeah and so
46:09
here we are trying to be immortal yeah it fits right into the theme because
46:14
here's an example of two deaths being described within the context of a single
46:21
work and the reality is quite distinct from the words that Shakespeare actually
46:29
uses he's BAE saying aye Shakespeare will be forgot the next right part is how he will die
46:35
threatening an epitaph he's running up imagine writing epitaph assume the dot and says you will carry on because my
46:41
words my pen is so powerful that symbolically you will achieve immortality whereas the poet will not be
46:49
remembered now how many people remember Shakespeare and how many people remember the epic did the person for the whom the
46:55
epitaph was written so it's a symbolic version it's exactly sort of reflects right back on ronk and becquer it's a
47:01
symbolic version of reaching beyond the mortal nature that we have and you know
47:08
that the question arises you know in some sense which is where do you get
47:17
that symbolic immortality from so one of the things that captivated me in in in
47:24
reading the various perspectives on these questions is a question that I was
47:30
asked you know many years ago after a conversation like this which was you
47:35
know which would trouble you more learning that you are gonna die saying
47:42
six months or learning that the entire species is going to be wiped out in six
47:50
months and it's a curious question to reflect on because at least for me my
47:55
response to each of those two is completely different you know my response to learning that I'm going to
48:00
die I think would be a desire to wring as much life out from the final six
48:08
months that I have if however I learned that the species are going to be wiped out in six months there's a sense of is
48:15
there any point doing anything any longer because there'll be no longer descendants who will be able to receive
48:22
anything that we create either real or symbolic that we imagine being passed on to the future so it's an interesting
48:29
question where do you put the weight of your own desire to not be as Robert
48:36
Nozick described it wiped out erased and
48:41
that brings us in this sort of pilgrimage to thinking
48:48
about myths and religion which you describe to some extent in your own sort of intuition as being railing precisely
48:55
against oblivion to mollify the anxiety of understanding our impermanence yeah I
49:03
mean there's exactly I mean there's a sense in which every religion is stephen jay gould noted that every religion
49:08
began with a recognition of our own mortality and it's not the only role that religion plays but a powerful way
49:17
of dealing with the recognition that your time is finite is to imagine that
49:23
it's not finite to invent myths where we're in the center and we triumph in we yes exactly and that's and there's and
49:31
if you think about it that's actually incredibly creative it is an amazingly
49:38
impressive move to ameliorate the otherwise debilitating impact of
49:45
recognizing that everything you care about everything that you're part of everything that has been within the
49:51
reality that you've experienced will go away how do you deal with it imagine that it doesn't now I'm going to by the
50:00
way he's going to tell us it does so but we'll get there but I do I do want to ask are you a religious person it
50:08
depends exactly what one means by religious person and I think you probably anticipated that would be the
50:14
answer that I'd give you IIIi don't consider myself a religious person in following the dictates and the
50:24
dogmas of any specific religion right I mean you know I was raised Jewish I
50:31
don't I don't practice that religion in in any systematic manner but I certainly
50:37
do consider myself to be a spiritual person and by that I simply mean I think
50:43
there's great value in not just trying to understand the external world which is pretty much what we have done with
50:50
our lives trying to understand the basic laws and the particles and cosmology and
50:55
things of that sort but there's something deeply important and wondrous of turning that lens inward and
51:02
trying to understand our own inner world our own inner experience and I consider
51:08
that to be a spiritual quest to figure out how we're part of this reality so in
51:14
that sense yes I mean you also describe both with language and with myth and religion these narrative layers that
51:21
give you a higher level truth within the rubric of being physical exactly and and
51:28
today I also wanted to ask you cuz I know that you have this unusual relationship with your brother where your view become this very influential
51:36
theoretical physicist and your brother is quite a religious person yeah very much in the sense of doctrines that are
51:44
adapted from history yeah I don't know if he's actually here at the moment Joshua okay I'll talk more freely no no
51:54
I say exactly what I said if he was here you know my brother's a good deal older than I am about 13 years older and so he
52:02
was growing up in the 60s a very different time and found things
52:08
distressing as many did in the late 60s and left America and traveled to Europe
52:14
and India and various places and became a Hari Krishna devotee your father
52:20
taking you to Central Park to watch the Hari Krishna's and this realization that one of them was your brother yeah it was
52:26
a nice way of introducing you to his brother's turn no it's exactly right you know one sunny Sunday afternoon I don't
52:33
know a seven or eight years old and my dad took my sister and he took me and we
52:38
went strolling you know and I think it's called poets walk right by the Birdman show and as we're walking along we
52:45
stopped because there was this big group of Hari Krishna devotees drumming and chanting and things of that sort and
52:51
over there in the corner I look and it's my brother and I had no idea I thought
52:57
it was a college I had no idea that this is the direction that his life had taken but you know he had you know the shaved
53:03
head with with just a hair and in one spot and the flowing robes and was out there uh you know energetically
53:11
part of this this ritual and does he remain with that same group um he does
53:20
and it's been an interesting and and curious and and long journey I mean
53:25
there were times you know when my brother would visit my father and you
53:31
know the the apartment in Manhattan and ultimately came to the conclusion that he couldn't visit any longer because he
53:37
couldn't bear to be in the room with somebody who was not a hard Christian devotee that's how it was in the early
53:43
days and you know this was hard my dad would would would cry with with
53:48
ferocious intensity at having lost what he viewed as losing his son because you
53:56
know of this perspective over time it has definitely mellowed and now you know
54:03
if my brother was here he no longer wears the robes and no longer has a particular outfit but he still deeply
54:10
devoted to that kind of spiritual journey and do you engage in conversations about your different paths
54:16
to meaning well we we do and we have certainly in the in the early days you
54:22
know when I was a graduate student in physics you know there are times that we would meet and I would tell them the
54:27
things that I was doing and working on even the discovery here there and at the
54:32
time almost everything that I told him about he would be like yeah Vedic text
54:38
number twelve you know so I was a little frustrating at some level but but at the
54:47
same time I recognized with hindsight now that what he was really saying was there was a resonance with the kinds of
54:55
questions that were firing me up and the kinds of questions that were firing him
55:00
up even though our pathways to try to come to terms with those questions were radically different yeah I'm glad you
55:07
reminded me of that because you have described how Hinduism and Buddhism are often touted as already having predicted
55:13
string theory or quantum mechanics or something else and you have a very good response to this I think in in in
55:18
particular in your conversation with the Dalai Lama so I'd love for you to have a chance to adjust that because it is a question I'm
55:25
sure you often get wasn't it already predicted quantum mechanics and all physics in in ancient texts right so so
55:32
there actually was an event some years ago down in down in Texas where I was
55:38
doing an event with the Dalai Lama and I had the opportunity to ask him some questions and one of the questions I
55:44
asked him was precisely that which was I said look there's so many books out there which claim that Eastern
55:52
traditions have long ago come upon the insights of modern physics and do you
55:58
think that's true and he just immediately answered with complete honesty and said I do not
56:05
he says when it comes to figuring out the deep nature of reality it is you guys it is the physicists that we need
56:12
to follow and we are happy to update our understanding of reality based on the
56:17
discoveries that you make at the same time he said when it comes to consciousness we have much to teach you
56:24
and that's the domain in which the insights from our practice can give
56:31
incredibly deep insights into nature of self-awareness and in the path of
56:36
self-awareness art looms large right it's the next kind of step in the ascent
56:41
and you describe in a really interesting way kind of the uselessness and from a
56:47
Darwinian perspective of art like why use all of these resources on something
56:53
that has no adaptive or survival value in the face of an angry bear or drought and and it's a kind of like sexual
57:01
selection argument but again I think you you kind of play that dance with maybe we know maybe we don't know about the
57:07
rejection what you think is the best that you can do in in these kinds of domains I don't think there's a
57:13
slam-dunk argument in any of these humanistic undertakings as to their
57:20
adaptive role or lack thereof but there are interesting arguments on both sides of the story and you know perhaps Steven
57:28
Pinker is well known for articulating one of the strongest statements about
57:33
the lack of a to utility of certain art forms music in
57:38
particular being one that he stresses he even goes so far as to say and I think many people are familiar with the quote
57:45
that these forms of art are nothing but mental cheesecake right right junk food
57:52
so so we have certainly adapted certain delight in eating things that are dense
57:59
with fat and sugar because in the ancestral world those of our forebears
58:05
who had a predilection for eating fleshy fruit and and ripen nuts they're the
58:11
ones that stored up on the calories that allowed them to survive when times turned lean but now here in the modern
58:17
world we create things like cheesecake that prey upon those adaptive sensibilities even though the Cheesecake
58:24
itself offers no nutritional value of its own and that's his view for certain
58:29
art forms they're preying upon our highly attuned say sonic sensitivities
58:35
right those of our forebears walking around the African savannah who were well attuned to a noise over there or a
58:41
sound over there were the ones who better understood their environment had a better chance of surviving music comes
58:46
along and then leverages that sonic sensitivity by pushing our pleasure
58:52
buttons in a way that offers in today's world no adaptive survival value at all
58:59
so that's sort of an extreme position of the exact of uselessness of art but he's
59:04
not making a comment about our appreciation or experiential the same way that you have been defending
59:10
consciousness is not being diminished by the reality of its physicality nor this
59:16
experience of some sense of freedom nor art yeah it is a mistake to assume that
59:22
the ultimate arbiter of value is whether something has an adaptive role it's not
59:29
it's simply a fact equality an element of how the world operates so Pinker
59:36
himself has great respect for and highly values artistic exploration and works of
59:43
art he's simply asking is it the case that these behaviors
59:48
are of value in one particular domain helping us to survive and in that one
59:56
barometer he's saying that they don't so do you agree with Pinker well I
1:00:01
personally don't my my you know it could be that you know my dad was a composer
1:00:07
was a musician I grew up around music from from the time I was crawling around right so that maybe has biased my
1:00:15
perspective but it feels to me and it feels to me deeply that artistic
1:00:21
exploration is vital to the ability to innovate the ability to think about
1:00:27
things in a different way you know Glenn Gould has this wonderful remark where he talks about a Bach fugue
1:00:35
and the way in which the melodic lines can be inverted and turned in on
1:00:41
themselves and yet even with that miraculous rearrangement of the notes
1:00:46
yields something that is deeply wondrous in its melodic line and I see physics in
1:00:54
much the same way what do we do we rearrange the building box of reality what did Einstein do in developing the
1:01:00
special theory of relativity he took the old ideas of space and time in the speed of light and he rearranged them in a
1:01:07
sparkling new configuration in which the speed of light was constant forcing space and time to be relative and that
1:01:13
rearrangement of the building blocks yielded a radically new picture of the world that turns out to be correct
1:01:18
and it feels to me that artistic exploration over the course of a hundred
1:01:23
thousand generations is what primed the brain - rearranging structures in the
1:01:29
world and creating new patterns and within those new patterns creating new insights into how the world actually
1:01:34
works it's a beautiful description and I often say theoretical physics is one of the
1:01:41
last places or one of the last disciplines in which with a straight face you can describe beauty as being a
1:01:47
motivating factor yeah and it really is I mean we can see one solution and another solution it comes to the same
1:01:54
answer at the bottom of the page but one is beautiful and want to somehow clumsy one is elegant one is elegant like the
1:02:00
universe yes and all of this really these assessments are assessments of conscious
1:02:07
minds that have some experience of freedom if only by the complexity of the internal prodigious arrangements that
1:02:13
they're allowed yes that you know came from exploiting the entry potential of
1:02:18
the universe you know came from this very austere beginning in a Big Bang that was just these principles driving
1:02:24
us to this point we are pretty sure we exist because after all consciousness is the only thing we're really sure of true
1:02:31
and then you bring us to the frontier of the end of time which returns us it sort
1:02:40
of leaves behind this complex tapestry for a second of these of these things
1:02:46
that emerged from from this complex evolution and and returns us to the austerity of entropy and the unfolding
1:02:53
of the universe you have an absolutely beautiful description of the to the best
1:02:59
of our knowledge the end that we face to a cosmological time yeah and I was
1:03:05
wondering if you would be willing to take us through some of that yeah sure um in in the book I use a metaphor to
1:03:11
try to help give the reader and frankly me as well an intuitive understanding of
1:03:18
time scales that really defy human intuition because to really talk about the far future of the universe you need
1:03:25
to talk about time scales that are fantastically longer than even the stretch all the way back to the Big Bang
1:03:32
so to do that I asked the reader and I'll ask you here now to go with me
1:03:37
imagine that we use the following metaphor imagine we have the Empire State Building and imagine that every
1:03:43
floor of the Empire State Building represents a duration that's ten times that of the previous floor so ground
1:03:49
floor is one year first floor ten years second floor 103rd floor a thousand and so forth so in this scheme we are going
1:03:56
exponentially far into the future as we climb up the stairwell of the Empire State Building now in this scheme
1:04:03
everything that's happened from the Big Bang until today extends to just above the 10th floor roughly 10 billion years
1:04:10
and as we go forward we're just going expand beyond that and I'll just take you through a couple of the floors to give a
1:04:17
sense of what happens by floor 11 the Sun is going to swell to over 200 times
1:04:22
its current size engulfing the inner planets and maybe even the earth as well by floor 14 most stars will have used up
1:04:30
their nuclear fuel and will fade to black by floor 19 the earth if it wasn't
1:04:36
swallowed up by the Sun on floor 11 it's now going to spiral into the dark Sun having lost energy through gravitational
1:04:42
radiation by floor 30 most stars will fall into the galaxy's central black
1:04:49
hole by floor 38 protons the very heart of complex matter are likely to
1:04:57
disintegrate showing that complex matter will be gone when you pass by the 38th floor by floor
1:05:03
50 any cogitating beings that still exist and there may simply be none
1:05:08
around once protons decay but if there are cogitating beings left in the universe they will think their final
1:05:15
thought because the actual process of thinking creates waste heat entropy that
1:05:21
the universe needs to absorb but by the floor 50 the universe won't be able to absorb it which means that when that
1:05:27
thinking being thinks one more thought it will fry in the own heat that it's thought generates between between floors
1:05:38
68 and the peak even black holes will disintegrate through a process that
1:05:43
Stephen Hawking taught us about they will radiate energy into space and disperse into a bath of particles that
1:05:50
will simply walk through an ever larger and ever colder cosmos that's it
1:06:03
so this really is the apex of the journey the idea that not just do your
1:06:11
particles cease to be organized in your particular way but that ultimately the
1:06:17
entire universe actually has an end an end where thought cannot be anymore and
1:06:25
I think it's very much embedded in your title until the end of time you don't you say something to the effect that
1:06:33
it's a noble charge that we have to try for ourselves to find meaning until the
1:06:40
end of time because after that shrug shrug there's one little epilogue that's
1:06:47
Brad as a footnote just to bring up when you have all these particles floating in
1:06:53
the void and when you have virtually unlimited time for them to meander around the cosmos there is something
1:07:00
weird that on occasion can happen those particles can slam into each other and
1:07:06
sometimes stick together in groups of two or groups of three or maybe even groups of four sometimes they'll disperse but sometimes they'll continue
1:07:13
to group into ever large configurations there is a nonzero chance that those
1:07:19
particles can come together to yield a particularly interesting structure a
1:07:24
human brain floating in the void imprinted say with the thoughts that say
1:07:30
it's my brain my brain there's actually a nonzero chance that if wait long and if my brain will reconstruct out there
1:07:37
in the void and if that were to happen that brain would think that it's having this conversation right now even though
1:07:45
that brain had no history whatsoever because it just spontaneously formed under the motion of particles so there
1:07:52
is a bizarre way in which thought may be resurrected over fantastically long
1:07:58
timescales I should just say what the time skills are the Empire State Building took us up to say ten to the
1:08:03
hundred years that's a really long time scale the time scale for a brain to form
1:08:09
in the void from the random two particles is 10 to the 10 to the 68
1:08:16
that is a fantastically long time scale but think about it there would be nobody
1:08:21
waiting around for that brain to form say hey come on brain like what's going on there and therefore if you have the
1:08:28
virtual eternity these weird things may possibly happen you also raise the
1:08:33
separator that the universe is infinite and we won't even go near the multiverse that actually they're called Boltzmann
1:08:39
brains yeah that the number of Boltzmann brains will exceed the number of what we call ordinary brains yeah that's quite
1:08:44
disturbing disturbing because if I if I were to ask anyone in the audience human
1:08:51
brain yeah well I say you know where did your brain come from and you say that's a little personal but I don't really mean it in that sense you know your
1:08:57
brain you would tell me emerged you know when you were born when you were conceived and you'd go through the whole
1:09:03
lineage you know your parents and grandparents and so forth and you might take us right back to the Big Bang that
1:09:08
might be the story you tell of where your brain comes from but as Janet just mentioned these weird so-called
1:09:14
Boltzmann brains that form out of the random motion of particles they can happen for a near eternity while your
1:09:21
story only holds water between roughly the 1st and the 10th floor of the Empire
1:09:26
State Building or maybe let's go to the 30th floor to be really generous in our assessment beyond that range there
1:09:33
simply aren't the particles to yield the kind of story that you just told
1:09:39
which means sheerly based on probabilities there are so many more Boltzmann brains out to Eternity than
1:09:46
there are brains that form in the traditional manner that you describe that if you're rational and and think
1:09:52
just about the numbers and probabilities it's far more likely that your brain just formed out of the void and thinks
1:09:58
it's having these experiences so the story you told was really beautiful and
1:10:04
quaint but it has no basis in reality if you allow for these brains to form in
1:10:10
the void which is a very disturbing conclusion even to physicists I should say because it undercuts rationality
1:10:17
itself if my brain could possibly have just formed in the void thinking that it
1:10:23
studied quantum anacs and general relativity and thinking that it understands the data
1:10:28
that supports those theories but if all that is wrong because it never happened
1:10:34
then i can't trust even the very laws that lead us to conclude that these brains should form in the void so we
1:10:41
really undercut our own sense of rationalism if we allow these crazy things to happen which means just to
1:10:48
summarize we physicists pretty much used this as a diagnostic tool if our theories really allow for these
1:10:54
spontaneous brains to form and avoid we think that our theory needs to be
1:10:59
reanalyzed reassessed modified in some way to get rid of this quality so you've
1:11:09
brought us to this precipice in which there is this ultimate death of even thinking itself in a universe that faces
1:11:18
a kind of oblivion that is totally profound and not specifically human and much more severe than that and yet in
1:11:24
the opening of this conversation you said but yeah yeah but yeah but i view this in a wonderful way and you I very
1:11:31
much feel that we're on this trip with you that this was something you were going through yes and and you come to
1:11:38
this point where you describe your own kind of epiphany this moment where you felt this calm connection and you
1:11:45
described a feeling of gratitude yeah like for experience itself yes and I
1:11:50
think that would be a beautiful place to hear you close this trip yeah well that
1:11:55
is is a good summary again because when you recognize that we are the product of
1:12:01
these laws that have no purpose they have no meaning they're they're not endowed with anything beyond the
1:12:07
mathematical qualities that they have and when you recognize that you realize
1:12:13
that there isn't some answer that's floating out there and rather you change your perspective and recognize that we
1:12:21
are the product of these laws acting themselves out from the Big Bang to the
1:12:28
present time and that involves a nearly infinite collection of quantum processes
1:12:34
right each of which could have turned out that way instead of yielding a reality which neither you nor
1:12:40
I nor any of us would exist and yet against those astounding odds we are
1:12:46
here and it's more than that it's not just that we're here we are collections
1:12:51
of particles as we describe that have the incredible capacity to think about
1:12:57
the world to reflect on reality and that to me gives me an incredible sense of
1:13:03
gratitude that collections of particles through a flitting burst of activity can create beauty can experience wonder can
1:13:12
illuminate mystery and that recognition is something that for me borders on
1:13:18
reverence how remarkable how stunning that we are here and that we can do the
1:13:23
things that we do and frankly in a world that has qualities that many of us find
1:13:29
distasteful dark chaotic destructive debilitating to have a sense of
1:13:34
reverence for our moment in the cosmic timeline adds something which I think is
1:13:39
deeply valuable Brian thank you so much
1:13:44
[Applause]
1:13:57
I am so thrilled that we've had Brian here and I and I got to hog the
1:14:04
conversation and we want to give everyone a chance to ask some questions so let's just keep those mics moving
1:14:10
we'll do about 10 minutes of questions keep those mics moving if you have a mic ask a question as soon as you're done pass it on and move that mic to somebody
1:14:16
else yes hi I have a question it's about I'm right over here
1:14:22
hi it's about Einstein and Einstein's idea about free will and when Michele
1:14:30
Besso died Einstein said to his widow essentially he's not dead because for physicists the
1:14:39
past the future the present are all illusions of course he believed in this
1:14:45
concept of a block universe so I my question is do you feel that basically
1:14:52
his belief was the future already exists so is there free will probably not but I
1:14:59
know that you support ideas that are closer to a multi Multi universe so I'm
1:15:05
just wondering like do you think the difference between the existence of freewill could be do we live in a block
1:15:10
universe something that's already said where the future exists or does every decision that every individual make
1:15:15
create a new universe yeah so it's a very good question and and one way of
1:15:21
framing that question which I think retains the essence of what you're asking is Einstein was viewing the world
1:15:30
in terms that we consider to be classical physics quantum physics was
1:15:35
something that didn't really move him in the way that it moves physicists today
1:15:41
and in a classical world you have the situation where if you tell me the state
1:15:48
of the world right now the equations dictate precisely what the world will be like later on and in that world it seems
1:15:56
virtually impossible to talk about freewill at all the future is locked in
1:16:01
place by virtue of the knowledge that you have of it today in a quantum world
1:16:06
things are a little bit different the quantum laws do not predict what things will be like tomorrow based on
1:16:13
how they are today they predict the likelihood the probability that they'll be one way or another tomorrow based on
1:16:19
how they are today now some people see in that an opening for free will they say aha it's the choice in some sense of
1:16:27
the outcome that's where we're able to intercede in the unfolding and the problem is that's utter nonsense because
1:16:36
the way quantum mechanics works is the outcome from the realm of possibilities
1:16:42
is a random choice that comes out of features of the world that we don't even
1:16:47
fully understand right now but we know that it's not something that comes from a volitional decision so if you learned
1:16:54
that the way your particles move was say governed by somebody flipping a coin
1:16:59
backstage with that probabilistic freedom give you a sense of autonomy I
1:17:05
don't think so that's not what we mean by autonomy that's not what we mean by free will and therefore the real way of
1:17:14
framing this problem from my perspective is not whether you're in a classical or quantum world it's not whether you have
1:17:20
deterministic laws or probabilistic laws the issue is do you have laws is the
1:17:27
universe lawful does it progress from here to there by a lawful progression
1:17:32
and if the answer to that question is yes and I think most physicists and I think most people think deeply about it
1:17:38
think the answer is yes then there is no room for the traditional notion of free
1:17:43
will because you cannot intercede in that lawful progression excellent we
1:17:49
have another mic question if you got the mic feel free to speak hi everyone
1:17:55
my question first I'm going to say I spent it and now an hour on the phone
1:18:01
with a quantum mechanic in Australia I went to school with and his question for you was was Peter Brock correct and I
1:18:08
thought it was a joke because Peter Brock was a racecar driver and now I've been listening you have to look him up
1:18:14
the quantum mechanic is a his name is Rob Proctor he's an based out of Niro -
1:18:22
Trey Leah but question is I geek out on blockchain and it's a bit off-topic
1:18:27
but could we use blockchain to travel back from the future well I'm gonna
1:18:34
leave this to Janna no I'm throwing it back at you but I'm gonna rephrase it there you you your it
1:18:41
doesn't matter if it's blockchain or anything else the question ultimately is there any mechanism by which we could
1:18:48
travel backwards in time we know we can time travel and you often point us out we know we can travel into someone
1:18:54
else's future yes through special relativity we know that that's absolutely possible that you and I could
1:18:59
part ways and travel at different speeds and you're different black holes and one I'll come back into your future and
1:19:05
we'll have lost sync but the question can I go into my own past is actually one that Einstein thought about yeah I
1:19:12
think many many many others have thought about this and I think the the Ferriss statement is that there's still a
1:19:19
possibility that you could travel to the past people have actually proposed mechanisms by which you could do that
1:19:26
usually the most prominent one involves wormholes wormhole you may know as a
1:19:31
tunnel from one location in space to another it's kind of a shortcut through space if you move the mouths of a
1:19:38
wormhole the openings lose synchronicity with each other and then you're no
1:19:43
longer just traveling from one position in space to another position in space you're moving for one moment in time to
1:19:49
another moment in time one directions going forward in time the other direction is going backward in time
1:19:54
although the mathematics in principle can work I think most physicists believe
1:20:00
that you could never realize this in the physical world first of all we don't know if wormholes are real I mean there
1:20:06
are in Deep Space nine and other you know so many sci-fi films we don't know if they're actually real we don't know
1:20:12
if you could actually traverse a wormhole so wormholes might be real out there but you can't actually travel
1:20:17
through them in the manner that you imagine with the tunnel so I think most physicists would say that when we
1:20:23
understand the laws of physics more fully travel to the Past will be ruled out but there's still the doors open a
1:20:30
crack I think is the most fair way of describing it so there are chronology protection conjecture switch asserted
1:20:36
that exactly that that when we fully understand the laws of physics that will not that will be just allowed but there are also stories and I think
1:20:42
Fineman told her really one of the great versions of the grandfather paradox where you you know a grandson goes back
1:20:50
in time kills his grandfather before his father was born and therefore could not
1:20:55
have been born to go back and because grandfather but you can try to make it since there is no freewill anyway that
1:21:02
the stories are totally self consistent and nobody can execute a test that's inconsistent with the laws of physics
1:21:07
right so that even if you can go into your past you simply won't be able to kill your grandfather you won't you
1:21:13
might graze him which makes him kind of psycho which makes your father not so good which makes you want to go back and
1:21:19
kill your grandfather right and as long as it's consistent everything's fine right anyone else about roediger I mean
1:21:30
he was trying to reconcile biology with physics and I thought that that some
1:21:36
biologists thought that was sort of problematic but I've heard a lot of biologists refer to biology has sort of
1:21:42
the messy science and then physics doesn't really explain everything in
1:21:47
biology and then also in terms of biology talk a lot about natural selection but somebody I'll just start
1:21:53
talking about survival the luckiest know that there is an actual such utility to
1:21:58
a lot of the traits that now in your book you make reference to Schrodinger's book on life yeah I mean Schrodinger
1:22:06
wrote a book you know called what his life in 1943 based on lectures that had
1:22:13
given the previous year and he was one of the rare physicists who was willing to move outside his domain of expertise
1:22:21
and try to use physics to address questions that other scientists have been pondering for some period of time
1:22:27
so I think now as we reflect back on what Schrodinger said he got a lot of
1:22:33
things wrong in that book you know it was the 1940s it was before the discovery of the structure of DNA
1:22:39
nevertheless he had many ideas that hinted at the right direction and and
1:22:46
the point that you're making is a good one as science progresses we challenge old ideas
1:22:51
try to refine them we try to ensure that they're better able to describe the better data that we acquire through our
1:22:58
intense investigations of the world and things will change over time but I think
1:23:04
the the bottom line assessment of Darwinian natural selection is that it's
1:23:09
rock-solid sure there are details around the edges that people are going to think
1:23:14
about and work on and refine over time but the core idea that Darwin gave us is
1:23:21
is alive well and solid let's take one more question if you've got a mic feel
1:23:29
emboldened I've got a mic if you don't
1:23:35
yes okay someone's getting one gotcha okay this may be a weird question so if
1:23:45
the structure of things from macro to micro is really kind of similar from
1:23:51
universe to galaxies to solar systems to have it in earth and having condors and cities and families and those families
1:23:57
are made of people and people are made of molecules and molecules are made of atoms couldn't we all be tiny conscious
1:24:05
particles within a live evolving universe instead of you know like a God
1:24:12
and a religion and maybe that's the tethering life force have you seen an animal house that question was was was
1:24:24
asked by the frat boys you know could we be in the fingernail of some giant being
1:24:30
and and you you know the answer I think
1:24:35
one way of thinking about an answer to that question is we as scientists look
1:24:43
out at the world we have certain theories about how the world works and
1:24:48
over time were forced to move incrementally away from all theories by
1:24:54
virtue of the new data the new experiments the new observations that we encounter but we're fairly loath however
1:25:01
while the ideas that we may have discussed here tonight we're fair loath to move to a place that's not
1:25:07
dictated by an observation by a measurement by a mathematical equation
1:25:13
emerging from ideas that themselves have already received a mountain of
1:25:18
experimental support so is it possible that the chain of conscious awareness
1:25:24
that you're describing may extend in the manner that you imagined it's possible
1:25:30
but there's nothing that leads us in the manner that I've been describing
1:25:35
incrementally from what we know to that very big version of conscious awareness
1:25:42
floating out there in the void so is it possible yes is it compelling not at the
1:25:48
moment so I have the privilege of being able to ask you the last question and I
1:25:55
was reminded in this conversation that you quote also Emily Dickinson and you say forever is composed of nouse and so
1:26:03
here we are now and so what how are you
1:26:08
going to seize this moment having been on this really I think quite provocative
1:26:14
evolution of your own what's now I don't know and that's really what makes it exciting you know I I think I think many
1:26:22
of us and and I think it's even more prevalent among kids today because I see it in my own kids there's a desire to
1:26:29
kind of map out the world map out the life impose the coherence that will
1:26:35
allow you to answer questions of that sort in terms of where you're going to be what you're gonna do and I think and
1:26:41
personally I think this partly comes from the focus on electronic gadgetry where we are constantly engaged with
1:26:49
something and never allowing the mind just to be so for the moment having spent this time writing this book
1:26:56
thinking about these ideas I just want to let my mind be and see where it goes
1:27:01
Brian such a pleasure thank you so much for joining us [Applause]