Leonard Susskind - Must the Universe Contain Consciousness?

Lenard the so called fine-tuning of our universe is a problem that everyone says demands explanation how could it be everything just so to enable us to exist you you have this very compact and and very dense phrase that you use to explain it it goes something like we need a landscape of possibilities that is populated by a mega verse of actualities now I really want you to explain that okay so what it means first of all what does the landscape mean the landscape doesn't mean the real world that doesn't mean the universe that's out there it means the collection of possibilities it means the collection of all possible blueprints for a universe the word was taken from the biologists the biologists speak about the landscape of biological designs by that they don't mean all the biological objects they mean all the possibilities for rearranging DNA all the possibilities that's what the landscape is but possibilities by themselves are not enough we need to create those objects it's like having a whole bunch of blueprints for houses but you have to have something to build the houses what was it in biology well it was Darwinian evolution acting on a bunch of carbon oxygen and so forth eventually filled out this enormous landscape of possibilities and created a biosphere of very very great diversity so what is the analog in the physical exactly and in the physical world assuming that my view was right the lens case why yes of course the landscape of possibilities is all of the diversity that's inherent in string theory string theory has components which are in many respects similar to DNA and you can rearrange them have very very microscopic distances in a huge variety of ways that creates a landscape of possibilities and each one of those possibilities could different laws of very different laws combinations of laws some war some of these worlds would have electrons some of them wouldn't have electrons and so forth but we also need whatever it takes to bring these possibilities into reality just in the same way that blueprints the builders have to come and build the houses that the blueprints described that we believe or at least some fraction of physicists believe was what this inflationary cosmology did the very very rapid expansion in the beginning of the universe created pockets pockets of this type pockets of that type pockets of another type much in the way that Darwinian evolution created all of the branches of life and filled it all out so the expectation then is that the universe is extremely big much bigger than we can see and full of all different kinds of environment and some would describe each of the separate pieces of the whole universe depends I'll use the term as a pocket universe or a bubble universe squeezed off from the rest with its own separate laws created by this inflation which may have ended in our pocket universe but continues on and others in others and continues to bubble and froth and create more and more and more environments and which which kind of environment do we live in well we live in one of those environments in which life is possible there's nothing surprising about that so that's the view that at least some fraction and I would say probably by now the majority of theoretical physicists are moving and now this is the so-called anthropic principle with you like the name or not it basically says that that as as human beings we have to be in an environment in which it is conducive for human beings to exist it sounds trivial tautological silly when you first think about it but as you use it it has greater explanatory power it has explanatory power but it is it does sound trivial we live we live because we couldn't live anywhere else but there's more to it than that it says whatever the controlling equations of physics are whatever they include controlling mathematics rules of nature are it permits enormous diversity that's not obvious that the equations of physics should permit this enormous diversity and also requires a mechanism to bring it into existence and that's not trivial we do have such mechanisms mathematical mechanisms and we do have a mathematics which produces this diversity so no it is not trivial we could have imagined a mathematics which just gives rise to two or three different possibilities and then the world might consist of separate regions one two or three and really have two different kinds of mathematics you have in mathematics of string theory at the most fundamental level and you have the mathematics of inflation chaotic excitation and eternally K right inflation at the other level both of which are working that's right and the analog in the biological world would be the mathematics of a DNA molecule all the different possibilities the way to rearrange it which is the string theory which is the string theory and the other mathematics would be the mathematics of Darwinian evolution how how species branch how they create new species and so forth and how eventually a big tree of life forms and the other Fourier is the chaotic inflation of the of the macroscopic level exactly okay I mean that sort of sounds reasonable sitting here in your living room why the controversy let's talk about the different kinds of country let's talk about in your field among theoretical physics because I've talked to some and many of them you know would say you would think about and they say it's too soon to give up what why do you why do you give up what do you give up trying to find the ultimate solution the one kind of system that will explain it all in one state the history of physics has always been this way we've always looked for the one way to do it sometimes we've had trouble but eventually we'll find it and we do that and anybody who wants to devolve into the anthropic reasoning is giving up of course now your answer you're asking of course a psychological question and I don't have a degree in psychology so I will do the best to try to answer it as I can you have to go back a dozen years or so to what physicists thought about these anthropic ideas they thought of them as being religious they thought of them as being the statement the world is the way it is because God made it so that people could exist physicists don't like to explain things that way they want the hard-nosed equations they want hard-nosed explanations based on the laws of science and so forth so they were very very I would almost say angry there was almost an anger at this idea that the universe was somehow made for us to live in that how should I call it that mindset was the mindset about the anthropic principle let us say 10 12 years ago it just rankled against physicists objectivity to introduce something as personal as saying the world was made for us to exist in and living but as time went on they found it less and less and less possible to explain the world as we see it and new kinds of explanations evolved which were not religious in the least they depended on this enormous diversity but they had in the back of their mind always that there was some some supernatural aspect to it the other thing was ambition I don't mean personal ambition I mean the ambition of the field the ambition of the field was to explain every single fact of nature the constants of nature the particles of nature the hope was that we would be able to use our equations to explain every single feature of nature and that just conflicted with the idea that nature could be enormous ly diverse it is almost as if at one time biologists had the ambition to predict exactly what a human being was like from the microscopic laws of chemistry well that didn't happen that's not the way it worked a human being could have had three ears he could have had two noses all kinds of differences could have been inherent in the DNA and the biologists had they had that ambition would have been frustrated some of them might've even gotten angry and said oh it can't be that way that's kind of what happened the ambition of physics to explain everything uniquely by some fundamental mathematical beautiful laws elegant laws got frustrated and so for a period of time physicists reject didn't reject they resisted this I would say that by now the there's been a reversal of fortune most physicists recognize if you were to hold a gun to their head and say explain to me the fine tunings of nature and if you don't give me the right explanation I'm gonna pull the trigger or you're gonna say god that would be worse that'd be abort already worse they would him and they would horn they would him and they would haw and then they would say Oh must be the multiverse and the landscape of string theory because there is no other explanation so there's been a reversal of fortune on the other hand we're all unhappy that our ambitions have been frustrated so some people myself included incidentally would say it's too early to give up the the ambition but it's not too early to start to think about the other possibilities and in fact the other possibility is namely this grand Anthrop multiverse landscape picture that one seems to be the way that most physicists are going now like it or not and they don't

Channel: Closer To Truth

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Keywords: closer to truth, deepest questions, ideas of existence, life's big questions, pbs science show, robert lawrence kuhn, search for purpose, stem education channel, ultimate reality of the universe, vital ideas, Leonard Susskind, Stanford University, Stanford Institute for Theoretical Physics, Cornell University, Professor Susskind, closer to truth leonard susskind, physical laws, Universe Contain Consciousness, consciousness, closer to truth consciousness, Susskind, Robert Kuhn

Id: z27k9_NP4FU

Length: 11min 12sec (672 seconds)

Published: Tue Mar 03 2020