08/09/2013
Andrei Linde on the Universe
Professor Andrei Linde, a native of Moscow, is one of the authors of inflationary cosmology and of the theory of the cosmological phase transitions. His current research involves the theory of dark energy, investigation of the global structure and the fate of the universe, and quantum cosmology. He is the author of more than 200 […]
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This is KZSU Stanford.
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Welcome to entitled opinions.
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My name is Robert Harrison
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and we're coming to your live from the Stanford campus.
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[Music]
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Why don't we start with Dante?
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No, not the Inferno, the Paredizo.
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All things among themselves possess an order, and this is the form that makes the universe like God.
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Within that order, every nature bends by diverse dispensations, more near or less near to its source.
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Thus they move to different ports over the mighty sea of being, each one under the God given impulse that bears it on.
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This impulse carries fire to the moon.
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This is the mover in mortal hearts.
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This is what binds the earth together and makes it one.
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The providence that has arrayed all this forever quiets with its light,
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that heaven wherein worlds the swiftness of the spheres.
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[Music]
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[Music]
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When Dante was riding in the 1300s, the universe was a beautiful place.
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Love moved the sun and the other stars in great concentric circles.
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The heavenly spheres were nestled into one another, and the hole was sublimely finite and self-contained.
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Then came the revolution and Pascal's post-coperanican dread.
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"The eternal silence of these infinite spaces terrifies me."
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A few hundred years after that came the brave new world of general relativity,
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which once again overturned the whole picture.
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Time and space were fused in ways that are still incomprehensible to the average person.
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But it didn't stop there.
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In the last hundred years that brave new universe has undergone significant metamorphoses,
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it's no longer what it was just a century ago.
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How can the universe keep changing its nature?
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And don't tell me that it's not the universe, but our concept of it that keeps changing.
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When our concept of it changes, the universe itself changes.
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It's no longer the same place.
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Think of it.
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Our Earth orbiting a sun in a remote region of a galaxy with billions of stars in it.
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That galaxy won among millions or billions of other galaxies and super galaxies,
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all part of a universe that may be won among many universes.
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Emerson begins one of his essays with the question, "Where do we find ourselves?"
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That's a question for our times.
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"Where do we find ourselves?"
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The question itself is disorienting.
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Does it ask, "Where are we?"
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Does it imply, "We are lost"?
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Does it suggest, "We're not where we're supposed to be"?
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We don't even know if the "where" has a spatial reference or a spiritual reference.
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And Emerson's answer only aggravates our disorientation.
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I quote, "Where do we find ourselves?"
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In a series of which we do not know the extremes and believe it has none.
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We wake and find ourselves on a stair.
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There are stairs below us, which we seem to have ascended.
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There are stairs above us which go upward and out of sight.
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But the genius, which according to the old belief, stands at the door by which we enter,
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and gives us the lathe-age-drink that we may tell no tales,
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"Mix the cup too strongly, and we cannot shake off the lethargy, now at noon day."
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Interesting.
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I, for one, believe that any attempt at self-orientation, be it spiritual, spatial, existential, or historical,
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must begin by asking, "Where do we find ourselves in the cosmic order of things?"
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But the problem is that the cosmos doesn't seem to stay put long enough for us to get our bearings.
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With every decade that goes by, our knowledge of its parameters seems to expand,
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and the parameters get more indeterminate.
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The science of cosmology today is on fire.
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The more we learn about the visible universe,
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the more astonishing are the theories proposed to account for its nature.
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What's taking place in cosmology today is as mystifying as it is fascinating.
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And why not talk with one of the world's most mystifying and fascinating cosmologists?
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His name is Andre Linde, from the Department of Physics here at Stanford,
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and he joins me today in the studio of KZSU.
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Andre, welcome to entitled opinions as a pleasure and honor to have you on the show.
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"Glut, glad to be here."
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Andre Linde was born and educated in Russia, and he accepted a prestigious professorship at Stanford in 1990,
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where he's been teaching ever since.
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He's one of the authors of what is known as the inflationary theory of the universe.
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Ever since this theory was first introduced a few decades ago,
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it has gradually gained more and more credence and is now widely considered indispensable to our understanding of the origin
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and nature of the visible universe.
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Professor Linde has kindly accepted my invitation to come on the show today
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to try to explain in layman's terms what his theory is all about
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and to speculate with us about what an inflationary universe means
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when it comes to the larger question, where do we find ourselves?
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Andre, I've heard you speak at lectures in colloquia, and you and I have had enough conversations over the years
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for me to be convinced that there's a kind of poetic sublimity in your theories.
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In fact, there is so much imaginative power at work there that I think of you as a great poet of cosmology,
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and I intend that as the highest of compliments, by the way, this is a literary talk show after all.
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It's difficult to know where to begin our conversations. I suppose we should start with a whole question of the big bang.
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I belong to a generation that came of age at a time when the big bang established itself as standard dogman in cosmology.
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According to the big bang theory, the universe originated some 15 billion years ago in a kind of explosion that created space and time and all the matter in the universe.
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The universe, if I understand things correctly, has been presumably expanding ever since.
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The conventional image for the big bang is that of an expanding ball of fire.
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Now, as I understand, your theory of a self-reproducing inflationary universe doesn't reject the big bang theory, but modifies it in several important respects.
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As a way of introducing us to your cosmology, could you maybe start by telling us why you think the big bang theory is not the whole story,
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and what your concept of inflation does to give us a more adequate picture of the universe we inhabit.
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I probably should start with telling what the big bang theory is all about, and then it will be easy for me to continue.
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The big bang theory, in fact, was not accepted at the moment when it was suggested.
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In the very beginning, there was some rational material, Alexander Friedman, who solved high-state equations describing how universe obtained the solutions which show that the universe is expanding, sent it to everyone, and then Einstein didn't like it.
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He didn't like it at all, because according to this theory, our universe appeared at some moment, time equal to zero.
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In the moment of the big bang, all of it suddenly, simultaneously, in all its different parts, it appeared to look similar in different parts of the universe, and there was no time to think, it just started existing.
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Now, this was opposite to the whole culture of Western sort.
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We believed that our universe exists and does not change. That was the standard European way of thinking.
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It was not an Eastern way of thinking. It was European way of thinking, but this way did not allow to think about the universe which changed in time, which evolves.
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So Einstein didn't like it, and he thought that the solutions of his own equations were simply incorrect.
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Now, after a while, he accepted that this is true, but mostly by the pressure of experimental evidence.
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People looked at the telescopes using telescopes at the galaxies. They have seen that galaxies are running away from us. All of these galaxies running away from us.
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And then they understood that the universe is indeed not static, not the way we thought about it.
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So this was the beginning of acceptance over the big bang theory. But still, it was with us not widely accepted until the 60s.
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And then in the middle of 60s and 65, people have found that our Earth is surrounded by some radiation coming from different parts of sky to us.
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And the only interpretation of this was that there was some primordial fire, and this fire was slowly dying of slowly cooling down.
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And that is why we are surrounded by remnants of cosmic fire from all directions coming to us, relatively uniformly.
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So after that, everyone accepted theory with the big bang, and it was flourishing until approximately the end of 17s.
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So in 70s, suddenly there are some problems when we try to marry particle physics and cosmology.
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We have found there are some problems. We have found that it's very difficult to make sense of these sciences together. One of them seemed incompatible with another.
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And then we start thinking about theory with the big bang, looking at its internal structure.
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This internal structure is good or not so good by itself. And we have found that it is full with some strange contradictions, with questions which are not answered and which actually we were afraid to ask.
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Let me give you an example of that.
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The simplest example is why the universe started expanding at the same time everywhere. Because if it's very large, then say one part of the universe started expanding, another part of the universe does not know yet that it is time for it to expand.
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I thought that if the big bang begins with an explosion of a very small particle of matter, then why wouldn't it expand uniformly? Why is that a country there?
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I probably should explain it like that. Look at the universe that we see at the moment.
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So at the moment we see as far as the age of the universe multiplied by speed of light.
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That's the largest part of the universe which is accessible to observations.
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But if we go back in time, then the universe was very, very young. And the part of the universe which was accessible to observations was very small.
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And once the world was in the age of the universe at that time, which was much smaller, multiplied by speed of light.
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So when we go to the moment of creation, the part of the universe accessible to observations was extremely small.
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And one part could not influence another. So the fact that the universe started expanding simultaneously in all of its different parts, and the properties of the universe in all of its different parts were approximately equal to each other.
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In other words, the theory of the big bang could not account for this.
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Yes. Einstein himself was puzzled by that, but he invented something which was called cosmological principle.
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And cosmological principle says that the universe must be homogeneous. It must be uniform.
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Well, why? Because it's cosmological principle. For a while, I did not know that this was Einstein who suggested it.
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So he used to make a joke that some people who doesn't have good ideas, they have principles.
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But then I stopped making this joke after I learned that Einstein suggested it. He simply did not know better at that time.
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Well, already, well, not a hundred years, but about eighty years passed after this principle was suggested.
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But he must have had some reasons for proposing such a principle, no? Yes, indeed.
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And the reason was that we looked to the right of us, we looked to the left of us,
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we see that the universe looked the same at a very, very large distance from us, density of matter is approximately the same to the right and to the left and forward and backward.
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So we needed to have some explanation why is it so. And the explanation was, well, maybe that's how it is. Maybe there is some basic principle which governs this homogeneity of the universe.
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But then it could not be right because we have information with galaxies.
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And galaxies are important for our life, if we just say that the universe must be everywhere the same, then it's also a contradiction with experimental data.
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So we need to understand why it's approximately the same, but not exactly the same. That's already a physical question.
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Then there are some other problems. One of the problems, well, with me, look, Celia and naive, but nevertheless, in school, thought that paralyzed no intersect.
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That's obvious the sum of the angle of triangle is 180 degrees. That's obvious, just try and measure and you see that it's always the case. It's always true.
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And that where this famous if-clead postulates. Then we go to the university and we learn that our universe actually may look differently from what if-clead thought.
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It may exist in three different ways. One is closed universe and it has properties similar to the properties of a surface of a globe.
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Like you moving near equator and you have paraleil lines which are paraleled to each other and then you continue moving and then this paraleil lines may intersect at the south and the north poles.
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So if we know that our universe could be like that, you may ask why nobody has seen this paraleil lines intersecting.
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So from, well, naive question becomes a physical question. Interesting thing about it.
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And it also will explain why nobody asked this question for so long time until the beginning of 80s.
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It is actually can be shown to be equivalent to a very, very see the question. Why there are so many people at Stanford University. Why there are so many people in Korea.
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Why there are so many people in the United States. The answer would be, well, the United States is just one of the countries. There are much more people in China, so nothing special about it.
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Why there are so many people in China. Oh, actually, there are just people on the surface of the earth. But there are hundreds of millions, actually about a thousand billion stars in our own galaxy.
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And then some of the stars has planted, some of these planets has people and some of these people will go to lecture at Stanford University. What's surprising.
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But why our galaxy is so large. Why it has so many stars. Interesting thing that our part of the universe contains about a thousand of billion of galaxies.
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So why our part of the universe is so large. And the answer is, well, because it's a universe and the universe, why it is large, but because this is a universe, it must be large.
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And that's where the discussion stops. But in fact, if we start applying this big bank theory to the universe as a whole and try to understand where it is natural or unnatural for the universe to contain so many people and so many stars and galaxies, the answer is no.
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The answer is that typical universe, according to the big bank theory, would not be large enough to incorporate one single person. So the fact that we see so many is a mystery.
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The fact that we see so many is a physical problem at a problem of science. It's not a stupid question for a long time.
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But we thought that these are just stupid and naive questions. So why should we bother what happened 20 to 25 years ago we learned that some of these stupid questions are not as stupid as they seem.
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And then we learned how we can answer them. And once we answer them, we cannot forget about it. That was the moment when inflation and the cosmology was born.
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So inflationary cosmology originated as a way of coming to the rescue of the big bank theory or was it something that was antagonistic originally with the big bank theory? Because if there were so many problems with the theory in the first place, why could one not come to the conclusion that the big bank theory is ultimately a myth.
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It sounds very much like creation X-nehi-lo. It sounds very biblical. It sounds like the monotheistic God who created the world in one instant out of nothing and so forth.
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So if it were not able to account or what the Greeks used to call save the appearances, because science and cosmology originally was, its business was to save the appearances.
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Why wasn't it not embedded entirely and in what way does inflationary cosmology both correct and come to the rescue of big bank theory?
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See, situation here is very similar to the theory of general relativity as compared to the old Einstein theory of gravity.
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Newtons suggested history of gravity works perfectly well. Then Einstein came and he found that Newtons theory cannot explain some subtle properties of orbits of mercury, things like that, bending of light in a new sun.
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So, well, there were some problems to which Newtonian theory would not give an answer, but in many other respects it was perfect.
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Same thing here, big bank theory was perfect and so many different respects, that it was very difficult to abandon it.
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People tried to replace it for so many years, not many like them. They tried to suggest, instead of the big bank theory, they tried to suggest a steady state theory of the universe.
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And then the theory failed, they tried to suggest something else and it also didn't work, so we were forced towards the big bank theory.
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And then we have seen, however, that some parts of it, they just ungrounded. They give rise to questions which we cannot answer if we remain in the real, well with the assumptions of it, that there was this big explosion in the very beginning.
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To explain you one other way of, well, formulating the problem is that, let's say talk about the energy of the universe.
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Do you know how much energy, how much matter, because from the point of view of Einstein theory there is no difference, matter of energy, the equivalent.
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So, how much energy do we need to produce the universe as we see it right now in the big bank theory?
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Well, in the very beginning, we need approximately 10 to the degree 90 tons of high-tech explosive.
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10 to the degree 90 means a billion of a billion of a billion of a billion, let me better stop here.
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Tons of explosive all compress to the small region of a size smaller than a centimeter.
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And then we need somebody to trigger this explosion with perfect accuracy so that this explosion will produce very homogeneous ball of fire.
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So, that was a mystery. Sounds like God to me.
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Now, one thing why people like inflationary theory is that we do not need any longer, this 10 to the 80 degrees of tons of explosive.
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Okay, let's talk about the cosmological theory, the inflationary theory.
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So, why do we not need that explosion?
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What accounts for this huge scale of the universe?
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I first give you a quick answer, what do we need?
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We need approximately less than one milligram of some other type of explosive, which we did not know about, like, 25 years ago.
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And this explosive, less than one milligram, should be compressed in a very tiny region of space, much, much smaller than one millimeter.
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And then we just let it go. And after we let it go, it produces not only our universe, but produces infinite number of other universes.
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What does let it go mean? Aha! Well, you start with this small part of space, filled with this scale of field.
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And let's assume that initially it did not move. If we study normal big bang theory and take a piece of space filled with this hot matter, and let's assume that initially it does not move, then it immediately collapses onto itself.
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But if we take this piece of space filled with this specific type of matter, which I'm going to tell you about, then instead of falling onto itself, it starts accelerating the expanse.
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Expanse was ever growing speed, very, very, very fast. The whole stage of inflation, which is this early explosive stage of expansion of the universe at the very early stages of its evolution, the whole stage could last maybe 10 to the minus 35 seconds, which in other words, 1 billion of a billion, so 3 billion of a million of a second.
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And that was enough to create our universe and more. That is how fast it was explaining. And practically no time at all, the whole thing expanded to the proportions that we know today.
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Yeah. So the main thing was to understand how we can do it and still not violate any normal loss of physics, not violate the famous Einstein bound, but nothing moves with the speed faster than speed of light.
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How could we produce the whole universe if we had only 10 to the minus 30 seconds for doing it the way the way I had violation of anything? How can we produce all matter in the universe if we start with a part of space with a mass small one milligram?
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It doesn't sound possible because we have this one milligram on the name we have everything, but we know that there should be energy conservation. So it looks like we're just in high tech cheating.
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Now I'm here, Professor of Stanford, maybe probably because they still could not find where we were cheating or maybe because we were actually trying to be honest, but the solution was very unusual.
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It was an unentrival required for this solution to have some very strange type of matter which is called scale of field. I don't want to go into details about it, but I never know.
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For our listeners, scale of our fields, S-C-A-L-A-R. Yeah. It is. Well, if we want to have any analogy of what it is, the best analogy, it will be still not exact, but nevertheless it will help a little.
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The best analogy is that you have 110 volts in the electric circuit here. Imagine that in the room you have just 110 volts, no zero.
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That would be no current. You have everywhere this 110 volts you will never notice it. The proof that you would not notice it.
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Have you ever seen this high voltage electric lines which had like 10,000 volts in them and then birds cheat on this high voltage lines and nothing happened into the birds.
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So have you ever seen birds which are touching by one hand, no one line and by another hand another line, no such birds. They are just fired. They evolutionary disappeared.
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Because what kills us is a difference between potential, electric, electrostatic potential, 110 volts or 210 volts in 10,000 volts would see just like another vacuum state.
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But if you touch by one hand, United States was 10 hundred volts and by another hand Europe was 220, you will be dead.
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So you are reacting only difference of potential. So this would be the mechanism for the exponential expansion.
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What is the mechanism is that you need something like that. You need a field like this electrostatic field which you do not see if it's constant.
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Which you do not see if it covers the whole universe homogeneously you do not notice that you are surrounded by it. And in fact there are some theories which tell that we are right now not flying.
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Every particle in our body has mass because we are surrounded by this scale field where immerse it into it. People already got nodal prices for this theory this called standard model of electric weak interactions.
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And people got several model prices for it. Or finding some particles predicted by the theory for development of the theory they still did not find the scale field.
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One big accelerator which is right now is in the process of being built at CERN Switzerland.
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It's largest accelerator to be built on the Earth. The main goal of it is to find the specific scale particles.
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If they will not find it, this will be a big problem. If they find it, this will be a triumph of science and this will make our life also easier.
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Because we need something like this field to explain the rapid expansion of the universe.
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So if I understood you correctly, if this accelerator at CERN does not find these particles then is inflationary theory in deep trouble?
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We will be doing well independently.
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Because this scale field is just one simplest version of the theory.
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And this is not the field that we are looking for at this accelerator where we need some hakales.
|
00:28:45.000 |
So we heard about the scale field. But the point for us who have trouble with certain degrees of abstraction and your theory posits this incredibly rapid expansion within milliseconds of what you called it.
|
00:29:07.000 |
You didn't even call it matter. It's a kind of state somewhere in space use.
|
00:29:11.000 |
Well, it doesn't matter, but it's unusual. It is unusual in a sense just like this electrostatic potential in the room. It looks like empty room. You don't see it.
|
00:29:21.000 |
So the universe would look like it is empty universe. You don't see this scale field except it has a lot of energy concentrated in it.
|
00:29:29.000 |
And that's this energy that makes it blow up.
|
00:29:32.000 |
But here's a parenthetical question, naive as usual. I always thought that space itself was the product of the Big Bang that it didn't exist per se before the universe came into being.
|
00:29:47.000 |
But I take you to be assuming that there was such a thing of space before the inflation phenomenon.
|
00:29:55.000 |
Well, here we are reaching the limits. What inflation did? It helped us to go towards this limit. It helped us to go towards the Big Bang and replace it by something easier, better to suggest a mechanism of how to make it less painful this creation of the whole universe which we see right now.
|
00:30:19.000 |
But it does not yet answer the question where the whole space came from. It's assumed that there was some small sheet of space with scale field in it did exist.
|
00:30:29.000 |
And after that we do the rest of the magic. But we don't know where the whole, this first sheet of space came from.
|
00:30:37.000 |
So this cosmology based on inflation, which you're one of the principal authors of, then started gathering a lot of steam, I believe, in the last few decades.
|
00:30:54.000 |
Because it more and more was able to explain certain common drums in the realm of physics.
|
00:31:04.000 |
Well, I would say that there were two reasons. First of all, for 25 years after inflation in the theory was suggested people were trying to come with any kind of alternative suggestions, how to improve the Big Bang theory and so far they failed.
|
00:31:19.000 |
So, to identify years, theories are worth that very long time in terms of lifetime of theory.
|
00:31:27.000 |
Second thing, we gradually start getting some information, some experimental confirmations to detailed structural theory.
|
00:31:36.000 |
For example, inflationary theory suggested that the universe is homogeneous but not exactly homogeneous.
|
00:31:43.000 |
There are some important inhomogeneous like galaxies. And inflationary theory predicted some particular way how this galaxy distributed in space.
|
00:31:53.000 |
Then we predicted also how this irrigation coming to our verses distributed.
|
00:31:59.000 |
And surprisingly, to our own astonishment many of our predictions have been experimentally confirmed.
|
00:32:06.000 |
But what brought us to the focus of interest during last few years is another product of inflationary theory.
|
00:32:16.000 |
Inflation allows the universe to be multi-faced if you wish.
|
00:32:23.000 |
Einstein thought that the universe is everywhere the same because you look around to the right of the end of the left if you see the same universe.
|
00:32:32.000 |
Inflationary theory tells you, you see only the results of expansion of one tiny speck of space.
|
00:32:40.000 |
But then if you consider another tiny speck of space, you do not see it, you do not know what is going on there.
|
00:32:47.000 |
So, we should explore the possibility that how universe and its different parts may be completely different.
|
00:32:53.000 |
We just do not see this part because they are so far away from us.
|
00:32:57.000 |
In fact, you say I am going to read what you say that the inflation was a part of the Big Bang theory,
|
00:33:05.000 |
but gradually the Big Bang theory became part of inflationary cosmology.
|
00:33:10.000 |
And recent versions of inflationary theory assert that instead of being a single expanding ballifier described by the Big Bang theory,
|
00:33:17.000 |
the universe looks like a huge growing fractal.
|
00:33:20.000 |
It consists of many inflating balls that it produce new balls which in turn produce more new balls at infinitum.
|
00:33:28.000 |
And so, what you were just saying is seem to imply that what we can see of our universe is just one of these infinite balls.
|
00:33:36.000 |
The universe was big enough to start with.
|
00:33:39.000 |
I mean mind-vogglingly, almost alienating the large with the galaxies and super galaxies.
|
00:33:45.000 |
And now the universe that we know and can see it has just become itself a spec within this larger framework.
|
00:33:55.000 |
It is not only a spec, it is not only this.
|
00:33:59.000 |
You see we have indeed this fractal and we have indeed one balloon producing another balloon producing other balloons.
|
00:34:06.000 |
So, the whole universe becomes eternal in time.
|
00:34:09.000 |
It never dies at a hole.
|
00:34:10.000 |
But in addition to this, they are multi-colored balloons.
|
00:34:14.000 |
They can have different properties.
|
00:34:16.000 |
You may have different, effectively different laws of physics in different balloons.
|
00:34:21.000 |
I should explain what I mean.
|
00:34:24.000 |
Usually people believe that there is one guiding law of physics which involves all theory theories of all interactions between all elementary particles surrounding us.
|
00:34:36.000 |
And nevertheless this may be just a small part of truth.
|
00:34:41.000 |
It is just what we observe around is one part of the universe.
|
00:34:46.000 |
Think about water.
|
00:34:48.000 |
For example, water can be liquid.
|
00:34:50.000 |
It can be solid.
|
00:34:52.000 |
It can be gas.
|
00:34:54.000 |
Now for fish.
|
00:34:55.000 |
Fish can live only liquid water, not in solid.
|
00:34:58.000 |
For fish it is a big deal.
|
00:35:00.000 |
Whether it is liquid water or solid water, but it is the same thing.
|
00:35:04.000 |
It is the same water.
|
00:35:05.000 |
So, similarly, you may have the same law of physics which explain to you all our universe.
|
00:35:13.000 |
And then nevertheless this law of physics can be realized differently in different parts of the universe.
|
00:35:20.000 |
It is a strange concept.
|
00:35:22.000 |
It was very foreign for all thinking for so many years.
|
00:35:26.000 |
But recently, especially during the last three years, the graduates started getting traction.
|
00:35:31.000 |
When people who describe theory of all elementary particles, so called string theory, the most popular attempt to describe everything,
|
00:35:43.000 |
then they learned that this string theory allows for existence of 10 to the degree maybe a thousand of different states,
|
00:35:51.000 |
like these three different states of water, ice and liquid and everything.
|
00:35:56.000 |
So here, string theory allows you to have almost in-depth and very large number of types of effective real laws of physics surrounding us.
|
00:36:07.000 |
So then our universe becomes a fractal which consists of different balloons, each of which look like it is produced by the big bank,
|
00:36:16.000 |
and each of which have different properties of elementary particles.
|
00:36:21.000 |
So the laws of physics that we thought were laws that applied universally could be very provincial in their space of application,
|
00:36:33.000 |
namely the universe that we know and that we inhabit and there could be different sets of laws of physics in other bubbles or...
|
00:36:43.000 |
I tell you this, that there are at least two or maybe more levels of approaching this question.
|
00:36:52.000 |
One is what I call conservative principle, and this conservative, of course right now, looks very radical.
|
00:36:59.000 |
Conservative means there is one law of physics for the whole universe, just one law.
|
00:37:06.000 |
But it is just realized it differently. The same thing as saying that water is everywhere, but in some places it's solid water, in some places it's liquid water, but it's the same water.
|
00:37:18.000 |
So you may think about one law of physics covering everything, and then you may make another step which is much more radical and say that actually our universe is just one representative of many, many, many universes.
|
00:37:34.000 |
And each of these universes may have completely different laws of physics applied to it, or maybe no physics at all, or maybe no quantum mechanics at all.
|
00:37:43.000 |
It is a little bit radical, so we are trying right now going step by step slowly, but the evolution of physics just brings us to the place we started from, and then things which look radical at some stage may become conservative.
|
00:38:01.000 |
Well, the question that I began with, where do we find ourselves seems to have become, from one point of view it seems to have become a hopeless question if what you say is indeed the case, because we begin with a pre-coperanican world where the earth is at the center of the universe.
|
00:38:25.000 |
We know exactly where we are, we are the very center of it, and gradually with the Coperanican revolution space becomes, infinite becomes relative and then relativity theory and now with inflationary cosmology it seems that we are flung further and further into the most remote provinces of an inconceivably complex and huge sort of universe.
|
00:38:52.000 |
It is fine, but here is, now maybe we can get a little bit philosophical, because in some of the papers of yours that I have read, you speculate very in a very fascinating way about human consciousness and the relationship that human consciousness might have to the universe that we are talking about, world of matter.
|
00:39:15.000 |
And when we talk about consciousness, we are talking about what you and I are doing right now, we are thinking about these things.
|
00:39:22.000 |
And here is where, maybe there is something happening in cosmology where there is a new centralization of the human subject in the sense that now I take you to be entertaining the thought that maybe human consciousness is not just an epiphenomenon of a evolution of a species that happened to be in the sense of the human consciousness.
|
00:39:44.000 |
But that maybe human consciousness might be much more central to the whole story of what the cosmos is all about than we had ever suspected before.
|
00:39:59.000 |
Is that oversimplifying?
|
00:40:03.000 |
Again, just like for the previous question, there is a conservative point of view on it and there is a radical point of view.
|
00:40:13.000 |
And conservative, which previously was considered radical, was that we live in a part of the universe which is consistent with our abilities to live there.
|
00:40:24.000 |
Like fish can live in water, it cannot live in ice, so what, that is not a problem.
|
00:40:30.000 |
We see our universe the way we see it in this vast space with different properties.
|
00:40:36.000 |
We can live only in three-dimensional universe.
|
00:40:39.000 |
We can live only in the universe which has some particular properties, elementary particles.
|
00:40:45.000 |
Even the mass of an electron would be two times smaller, two times larger, would be dead.
|
00:40:51.000 |
If the mass of a proton would be two times smaller, two times larger, would be dead.
|
00:40:56.000 |
We live in a part of the universe where these masses are the way they are.
|
00:41:02.000 |
And there is no mysticism in it and there is no relation to consciousness.
|
00:41:06.000 |
It just affects.
|
00:41:07.000 |
There are so many different places and we occupy the place where we can live.
|
00:41:12.000 |
This is called "Antrophic Principle".
|
00:41:14.000 |
This principle was hated by physicists.
|
00:41:17.000 |
They hated it because they wanted to have a unique explanation for all properties of all elementary particles, everything.
|
00:41:26.000 |
And now we have this huge diversity of possibilities and people don't like to have diversity.
|
00:41:34.000 |
They wanted to have one unique prediction.
|
00:41:37.000 |
This is yet before we even talk about consciousness.
|
00:41:42.000 |
Even this was attacked by those physicists who wanted to be very conservative for the old style.
|
00:41:51.000 |
Just to try to explain everything uniquely which was a great goal but right now it does not seem that this is realistic.
|
00:42:01.000 |
I grew up, I mean, nourished on the phenomenological tradition, European philosophy, where one of the basic presuppositions of that beginning with Emmanuel Kant and so forth is that space and time, for example, are a priori forms of intuition of that human beings happen to have.
|
00:42:21.000 |
Whatever access we have to the world has something to do with who we are.
|
00:42:27.000 |
If you don't mind, let me read you a passage from Heidegger.
|
00:42:30.000 |
He's about as mystifying in the realm of philosophy as some of the cosmology we've been talking about is in your field.
|
00:42:36.000 |
Heidegger says that "design" is word for human existence.
|
00:42:41.000 |
That only so far as there is design is their truth.
|
00:42:49.000 |
That Newton's laws, the principle of contradiction, any truth whatsoever, these are true only so long as design is.
|
00:42:57.000 |
Before there was any design there was no truth nor will there be any after design is no more.
|
00:43:03.000 |
For in such a case truth has disclosed its uncovering and uncovering us cannot be.
|
00:43:09.000 |
Before Newton's laws were discovered they were not true.
|
00:43:13.000 |
It does not follow that they were false or even that they would become false if no discoverness were no longer possible to say that before Newton his laws were neither true nor false cannot signify that before him there were no such entities as have been uncovered.
|
00:43:28.000 |
Through Newton the laws became true and with them entities became accessible in themselves to Dazzan.
|
00:43:35.000 |
That's amazing and that resonates quite well with what we're studying right now.
|
00:43:43.000 |
Again, let's start with something conservative and let's then see that this conservative is internally inconsistent and move with something which you see is very similar to what you said.
|
00:43:57.000 |
So our conservative assumption was that we have all universe.
|
00:44:01.000 |
This is just the whole thing. Let's study quantum mechanically.
|
00:44:04.000 |
We know that quantum mechanics is science which is supposed to describe everything.
|
00:44:09.000 |
So well this is try to apply quantum mechanics to the universe as a whole because it should apply to everything and then the start finding strange things.
|
00:44:20.000 |
That if they apply quantum mechanics to the universe at a whole they can prove that the universe cannot change in time.
|
00:44:29.000 |
That's just a mathematical statement that seems weird. Sound weird. It is weird but that's the statement which can be proven.
|
00:44:39.000 |
I can't explain it technically but I doubt that you really want to hear it. What is important is some statement that the total energy of the whole universe, the total energy involving energy of matter and energy of gravitational field together is exactly equal to zero.
|
00:45:01.000 |
All energy that we see right now appeared because of the splitting of this zero into positive energy of matter and negative energy of gravitational interaction of different parts of matter.
|
00:45:13.000 |
So we have the total zero but it's split.
|
00:45:16.000 |
Now if you take this fact into account that you have a total zero then you can prove quantum mechanically that the universe at a whole cannot evolve. I would not go to technicalities.
|
00:45:27.000 |
When people who found it they suggested a resolution of this problem. They say we never ask questions why the whole universe changes the way we see it.
|
00:45:38.000 |
We ask questions why do we see the universe changing? They divide the universe into an observer and the rest of the universe.
|
00:45:47.000 |
And they ask how this observer see the universe evolving. So then they divide the total energy of the universe into the energy of an observer and the energy of the rest of the universe.
|
00:45:59.000 |
Two of these energies together give you exact zero and if you describe the simultaneous evolution you will see that there is no evolution.
|
00:46:09.000 |
But if you take energy of the rest of the universe it will be exactly equal to the minus energy of an observer.
|
00:46:18.000 |
So if you have an observer then the rest of the universe has energy and you can show that it can evolve in time. It changes in time because you have an observer.
|
00:46:29.000 |
Until you cut off an observer out of the universe the universe is dead. The universe starts moving depending on time only after you have an observer or many observers observing them.
|
00:46:44.000 |
That's fascinating. So you must have an observer and the rest of the universe and this observer must make observation and think.
|
00:46:51.000 |
That's fascinating.
|
00:46:53.000 |
But how does one measure the energy of an observer?
|
00:46:57.000 |
Is it possible?
|
00:46:58.000 |
Einstein theory is very simple about that after the accepted. The energy of observer is equal to the mass of the observer multiplied by the speed of light squared.
|
00:47:08.000 |
This is the famous formula which you can see at the t-shirt all the time is equal to MC squared.
|
00:47:15.000 |
So effectively what we say is that the mass of the rest of the universe is equal to the minus my mass.
|
00:47:23.000 |
After I have a dinner today my mass will grow by a little bit so the rest of the universe will also grow a little bit except for any different direction.
|
00:47:33.000 |
And its mass will become negative but it will be equal to minus my mass. However strange and fantastic sounds that's the thing which we know for about what we know.
|
00:47:44.000 |
But it tells you that in my E-for-proach that the universe exists without us observing it. He's indeed naive.
|
00:47:58.000 |
So when we want to interpret what we see you must add an observer to this.
|
00:48:03.000 |
Then of course the person who have understood it the first it was Bryce David in '65 he was a father of quantum cosmology.
|
00:48:12.000 |
He has written but we did not really need real observer observer with consciousness.
|
00:48:20.000 |
To look at what is going on in the universe we can just have any measuring device and let this measuring device the recorded data.
|
00:48:29.000 |
So the rest of the universe will depend on time measuring by this measuring device.
|
00:48:34.000 |
But then you ask a question who is looking at this measuring device.
|
00:48:38.000 |
So if we want to make a measuring device just not disclose the meaning of things to use hydrogarion terms.
|
00:48:46.000 |
So it looks like you necessarily have a pair or maybe even people's.
|
00:48:53.000 |
You need to have a pair of the rest of the universe and observer and consciousness of observer to make sense of what we are observing right now.
|
00:49:05.000 |
And then when observers die I don't know what is going on with the total universe.
|
00:49:11.000 |
So then our language becomes maybe poetic, maybe confusing.
|
00:49:16.000 |
This is not something which we can't touch within the next few minutes because this belongs to such questions that if you say a little bit about that it seems stupid.
|
00:49:29.000 |
If you say a lot about that it seems incredibly complicated.
|
00:49:34.000 |
And we need to have a balance so I don't know where to stop here.
|
00:49:37.000 |
I am just saying that here is a part of science which is extremely mysterious and which brings us to the boundaries of the standard scientific approach.
|
00:49:47.000 |
We need to improve consciousness to it.
|
00:49:50.000 |
Well I have two reactions. One is that there is something about the old tradition of humanism where man was the measurable things.
|
00:50:02.000 |
And this kind of anthropomorphism has survived in various guys as in our own reality.
|
00:50:09.000 |
This earth is that the human has completely centralised itself and monopolised the power among all the other living species.
|
00:50:16.000 |
The destiny of life on earth at least depends on the human.
|
00:50:20.000 |
And one, some of us who are actually filled with anguish at the prospect that the human is the measure of all things would take consolation from cosmology that we are actually in the final analysis just an accident that happened to happen.
|
00:50:36.000 |
My worry is that with also the idea of the observer that once again there is a recentralisation of human consciousness into the picture.
|
00:50:47.000 |
That is my own personal problem.
|
00:50:50.000 |
The other thing I wanted to say on Jay is that this is I think cosmology, the way you are describing it is where some of the purest poetry is taking place.
|
00:51:02.000 |
What is in your opinion, what role does the human imagination play in advancing our understanding of these phenomena?
|
00:51:15.000 |
Not just scientific analysis and theorems but the imagination.
|
00:51:20.000 |
I remember that Einstein said that for him the stievsky played much greater role than some famous philosophers.
|
00:51:29.000 |
Because the stievsky sometimes asked questions and what was brave enough to propose answers which were unusual at first completely shocking but then he tried to expand and go to the final logical conclusion.
|
00:51:48.000 |
Even this logical conclusion doesn't feed to the standard accepted way of thinking.
|
00:51:56.000 |
That is something which we are trying to learn how to live with all the time.
|
00:52:02.000 |
We are trying to ask questions which are unusual which may seem really wrong.
|
00:52:09.000 |
Sometimes we ask questions and then we look at our colleagues and they look at us and they think that we are just plain stupid.
|
00:52:17.000 |
Think about this beginning of inflation theory.
|
00:52:22.000 |
The questions which we ask where why part of the alliance parallel isn't it a stupid question?
|
00:52:29.000 |
We ask questions why there are so many people on the earth.
|
00:52:33.000 |
It is a stupid question everybody knows that there are so many people why it is even a problem.
|
00:52:38.000 |
We ask questions why the universe started its expansion in different parts simultaneously.
|
00:52:44.000 |
So these questions seem stupid.
|
00:52:47.000 |
Now you need to have some kind of imagination which allows you to go a little bit of the standard line of thinking which is accepted at this particular period of time.
|
00:53:02.000 |
You should not go too much off.
|
00:53:04.000 |
It is fine.
|
00:53:07.000 |
Yeah, like when we are doing physics we always are trying to do both.
|
00:53:14.000 |
We are trying to contribute to solid body of knowledge which does not require any outrageous hypotheses.
|
00:53:25.000 |
And then we are at least confirmed to our own colleagues that we are still sane in what we are trying to do.
|
00:53:32.000 |
Because otherwise if we just speculate about many universes, well there are many other people who speculate about many universes.
|
00:53:40.000 |
You must do something which will slightly fit into the standard part of knowledge.
|
00:53:47.000 |
Allow other people to hear that this allows us to explain some other people which are the problems which otherwise would remain unsolved.
|
00:53:55.000 |
Then you can slowly move. But what you need to do it, you need to allow yourself just a little, just a little.
|
00:54:03.000 |
But nevertheless this fuzzy thinking may be poetic thinking.
|
00:54:09.000 |
May be allow yourself to think by logical categories.
|
00:54:14.000 |
May be allow yourself to study Eastern philosophy not only Christian one so that you may not always think about one goal and one truth.
|
00:54:27.000 |
But think about many possibilities, many truths, maybe not unique answers.
|
00:54:33.000 |
Then you will be better prepared by emerging yourself into different archetypes of thought which we have prepared for you by different branches of civilization.
|
00:54:47.000 |
Then you maybe will be better prepared to attack these questions which otherwise would be more dangerous and more intimidating.
|
00:54:56.000 |
Yeah that's great. For Einstein it was Dostoevsky.
|
00:55:00.000 |
Was literature poetry ever or something that played any part in your own career even as a cosmologist?
|
00:55:14.000 |
First of all I should not be very original in this place for me Dostoevsky and Dostoevsky also were the leaders when in my youth I was reading and reading them and I was reading not only what Dostoevsky have written but all of his diaries and all of his commands which he had written when he prepared his books because it was allowing me to see how the human thought could ever
|
00:55:43.000 |
came to the concept which he came with. But also he moved in usually with that. I was reading poetry and remembering it by heart.
|
00:55:54.000 |
There was a lot of poetry which was at some stage forbidden in Russia and the only way to learn it was to type it yourself and to produce several different copies and give it to your friends and also to learn it by heart.
|
00:56:11.000 |
So I knew by heart hundreds of poems of Russian poets of the beginning of the century.
|
00:56:18.000 |
Which poets have you all mind my asking?
|
00:56:20.000 |
The title "Monderschtam Pasternak Machmatua"
|
00:56:26.000 |
They had a symbolic way of expressing their thoughts and sometimes you read their poetry the first glance it does not make any sense.
|
00:56:37.000 |
And then later you grow up with it and you start enjoying it and it started opening new horizons and new way of looking at the same things which you looked before will become multi-dimensional.
|
00:56:53.000 |
So it actually helps you a lot.
|
00:56:55.000 |
Well that's one of the founding creeds of this program here on the entire opinions which is that literature is not something that you do.
|
00:57:04.000 |
Either for your own private passions or hobby or pastime but that through exposure to the kinds of symbolic worlds that literature embodies that it has everything to do with the ways of thinking about the universe for example or any other
|
00:57:23.000 |
domain one might be engaged and so I'm delighted and I know most of the listeners of this program will be delighted to hear that there might still be there might be a debt to these poets that you are reading and these other writers in the kind of fascinating work that you're doing in the realm of cosmology.
|
00:57:43.000 |
You know what once I was asked what can actually kill your theory?
|
00:57:50.000 |
The way the theory that you proposed can be demolished or whatever and usually people in my profession they answer this way that well experiment can show that the theory is wrong.
|
00:58:06.000 |
I answered it in a different way I said this theory will be killed only by a better theory.
|
00:58:12.000 |
And when I answered this I had a mind something which was in my education long time ago reading this poet or shift my understanding one of all of him's points.
|
00:58:23.000 |
He once have written something about that I do not afraid Stalin I do not afraid what other people can do with me only a better poet.
|
00:58:34.000 |
Only a better poetry can kill my poetry so the same thing is here only a better theory can kill what we're doing right now.
|
00:58:42.000 |
Well I'm not in your field but I just have this feeling on day that there's not going to be a better theory or more poetic theory than yours for quite some time so I hope that they will be.
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00:58:54.000 |
Well it might be even another one of yours and thank you so much for coming on the program and I hope that we will be able to get you back to continue this conversation.
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00:59:03.000 |
Thank you for hitting me.
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00:59:05.000 |
Yeah.
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00:59:06.000 |
I want to remind our listeners we have a web page for entitled opinions you can log on to the Stanford French and Italian department homepage click on entitled opinions and there you can leave your comments and you can also access all the previous shows and listen to them online podcasts and so forth.
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00:59:27.000 |
Thanks again today but Lomas he's the producer of the show and we always own a debt. See you next week.
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