What do you think about the ultimate reality

Why does the universe exist? Why is there ... Okay, okay. (Laughter) It's a cosmic mystery. Be serious. Why does the world exist, why are we in it? Why is there anything at all instead of nothing? I think that's the ultimate "why".

So, I'm going to talk about the mystery of existence, the riddle of existence, what the state-of-the-art is about how to solve it, and why you should care. I hope you are interested. The philosopher Arthur Schopenhauer said that those who do not think about the nature of their existence, about the nature of the existence of the world, are mentally handicapped. It's a bit tough, but it's true. (Laughter) It has been called the most sublime and awe-inspiring mystery, the deepest and most far-reaching question man can ask. It has captivated great thinkers. Ludwig Wittgenstein, perhaps the greatest philosopher of the 20th century, was amazed that there was a world at all. In "Tractatus", Proposition 4.66 he wrote: "The mystical is not how things are in the world, but that the world exists." And if you don't like receiving your epigrams from a philosopher, try a scientist. John Archibal Wheeler, one of the greatest physicists of the 20th century, teacher of Richard Feynman, who coined the term "black hole", said: "I want to know where quantum comes from, where universe comes from, where existence comes from. " And my friend Martin Amis, - Sorry for throwing so many names around, get used to it. - my good friend Martin Amis once said that we are about five stone stones away from unraveling the mystery of the origin of the universe. I'm sure there are five Einsteins in the audience today. Any einstein? Hold hands? No? No Einstein? OK.

So the question why there is something instead of nothing; this lofty question was asked quite late in intellectual history. At the end of the 17th century the philosopher Leibniz asked this question, a very clever fellow of this Leibniz. He invented calculus independently of Isaac Newton around the same time. But for Leibniz, who asked why there was something instead of nothing, it wasn't a big secret. He was or pretended to be an Orthodox Christian in his metaphysical reflections, and he said it was obvious why the world exists: because God created it. And God actually created out of nothing. That's how powerful God is. He doesn't need any existing matter to create a world out of it. He can just do it out of total nothing, ex nihilo. By the way, that's what most Americans believe in today.

The existence of the world is no mystery to them. God made them.

Let's put that into an equation. I don't have slides, I'll mimic my graphics, use your imagination. So we have: God + nothing = the world. OK? That's the equation. Maybe you don't believe in God. Perhaps you are a scientific atheist or an unscientific atheist and you don't believe in God and are not satisfied with it. By the way, even if we take this equation, i.e. God + Nothing = the world, there is also a problem: Why does God exist? God does not exist by pure logic unless you believe in the ontological proof of God, and I hope you do not, because it is not good proof. If God exists, it would be conceivable that he would think, "I am eternal, I am omnipotent, but where do I come from?" (Laughter) "Where am I from?" God expresses himself a little more formally. (Laughter) So one theory is that God was so bored of pondering the mystery of His existence that He created the world to distract himself. Anyway, let's forget God for once. Let's take God out of the equation: ________ + nothing = the world. If you are a Buddhist you might want to stop here. Because now we have: Nothing = the world, and because of the symmetry that means: the world = nothing. OK? And for Buddhists the world is just a lot of nothing. It's just a great cosmic void. We think there is a lot of anything out there, but only because we are slaves to our desires. If we let our desires dissolve, we will see the world as it really is, a void, a nothing. We can move into the happy state of nirvana, which is defined as having just enough life to enjoy being dead. (laugh)

That is the Buddhist way of thinking. But I come from the western world and I am still preoccupied with the mystery of existence. So I have: _________ + - it's about to get serious, so - ________ + nothing = the world. What are we packing into this gap? How about science? Science is our best guide to the essence of reality, and the most fundamental science is physics. It tells us what bare reality really is, it shows what I call DWUEEDU, "the true and ultimate establishment of the universe". So maybe physics can fill that void, and in fact, since about the late 60s or around 1970, physicists have pretended to be able to explain, in a purely scientific way, how a universe like ours could just suddenly exist out of nowhere: quantum fluctuations out of the Empty. Stephen Hawking is one of those physicists, more recently Alex Vilenkin, and it was popularized by another very good physicist and friend of mine, Lawrence Krauss, who wrote the book A Universe Out of Nothing, and Lawrence believes that he has a solution - by the way, he's a militant atheist, so God is out for him - the laws of quantum field theory. The most modern physics can show how out of nowhere - no space, no time, no matter, nothing - a small lump of false vacuum can fluctuate into existence, and then inflate itself through the miracle of inflation to this huge and diverse cosmos, that surrounds us.

Okay, that's a really brilliant scenario. It's very speculative. It is fascinating. But I have one big problem with it and that is: It's a pseudo-religious approach. Lawrence thinks he is an atheist, but he is trapped in a religious viewpoint. He sees physical laws as if they were divine commandments. For him, the laws of quantum field theory are like fiat lux, "Let there be light". The laws have some kind of ontological force or power so that they can create the abyss and it will be full of being. You can bring the world to life from nowhere. But that's a very primitive idea of ​​physical laws, isn't it? We know that physical laws are actually generalized descriptions of the patterns and regularities in the world. They don't exist outside of the world. They have no ontic power of their own. You cannot create a world out of nothing. This is a primitive view of the laws of science. And if you don't believe me on this, listen to Stephen Hawking, who himself proposed a model of the cosmos that was self-contained and did not need an outside cause or creator. After suggesting it, he admitted that he was still facing a mystery. He said, "This model is all equations, what breathes life into them and creates a world for them to describe?" That left him at a loss. Equations alone cannot work magic; they cannot solve the riddle of existence. And besides, even if the laws could do such a thing, why these laws? Why the quantum field theory, which describes a universe with a certain number of forces and particles, etc.? Why not completely different laws? There are many, many mathematically coherent laws. Why not no laws at all? Why not pure nothing?

Believe it or not, this is a problem that thoughtful physicists get really into, and that's where they often get philosophical. Perhaps the laws that describe our universe are just a set of laws and only describe a part of reality, but perhaps each coherent set of laws describes a different part of reality and all possible physical worlds actually exist, they are all out there. We see only a small part of the reality that is described by quantum field theory, but there are many, many worlds, parts of reality that are described by completely different theories, which differ from ours in unimaginably unimaginable ways, which are unthinkably exotic . Steven Weinberg, the father of the Standard Model of Particle Physics, was quite taken with the idea that all possible realities actually exist. Just like the younger physicist Max Tegmark, who believes that all mathematical structures exist and that mathematical existence equals physical existence and that we have an enormously rich multiverse that encompasses all logical possibilities.

In taking this metaphysical way out, these physicists and philosophers are resorting to a very ancient idea that goes back to Plato. It is the principle of perfection or fertility, or the great chain of being, that reality is actually as complete as possible. It is as far as possible from nothing.

So we now have two extremes. We have pure nothingness on one side, and we have this view of reality that includes all conceivable worlds on the other extreme: complete reality, nothing, the simplest reality. What is there between these two extremes? There are all sorts of in-between realities that contain some parts and others don't. One of these intermediate realities could, for example, be the most elegant mathematically, which leaves out all inelegant aspects, the ugly asymmetries and so on. Now there are physicists who will tell you that we actually live in the most elegant of realities. I think Brian Greene is here in the audience. He wrote a book: "The Elegant Universe". He claims that the universe we live in is mathematically very elegant. Don't believe him.(Laughter) It's a pious wish and I wish it were true, but I think that he confessed to me the other day that it's a really ugly universe. It's stupidly built, it has way too many random coupling constants and mass ratios and superfluous families of elementary particles, and what the hell is dark energy? It's a stick-and-gum machine. It's not an elegant universe. (Laughter) Then there is the best of all possible worlds in an ethical sense. You should get serious now, because that would be a world where sentient beings do not suffer unnecessarily, where things like childhood cancer or the Holocaust do not exist. It's an ethical concept. However, between nothing and complete reality, there are special realities. Nothing is special. It's the easiest. And then there is the most elegant reality. It is special. The whole reality is special.

But what are we forgetting here? There are also the shoddy, unspecific realities that are in no way special, that are somehow random. They are infinitely far from nothing, but they also still lack an infinite amount of perfection. They are a mixture of chaos and order, mathematical elegance and ugliness. So I would describe these realities as infinite, mediocre, incomplete disorder, an unspecific reality, some kind of cosmic junk pile. And these realities, is there a deity in one of these realities? Maybe, but the deity is not perfect like the Christian-Jewish deity. The deity is not kind and omnipotent. It could be 100% malicious instead, but only 80% efficient, which pretty much describes the world we know I think. (Laughter) So I suggest that the solution to the mystery of existence is that the reality we live in is actually one of those unspecific realities. Reality has to be somehow. It can either be nothing, or everything, or anything in between. So if it had a special quality, such as being very elegant or complete or very simple like nothing, that would require an explanation. But if it's one of those random, unspecific realities, there's no further explanation. And that's actually the reality we live in, I would say. That's what science tells us. Earlier this week there was exciting news that the inflation theory, which predicts a big, infinite, messy, random, pointless reality - it's like a big foaming champagne that gushes out of the bottle forever, a huge universe, mostly wasteland with it little patches of charm, order and peace. This inflationary scenario was confirmed by observing the signature of the gravitational waves from shortly before the Big Bang with radio telescopes in Antarctica. I am sure you have all heard about it. So, anyway, I think there is some evidence that this reality is what we live in.

Why should you care? So - (Laughter) - the question, "Why does the world exist?" is the cosmic question that somehow rhymes with a more intimate question: Why do I exist? Why do you exist? Our existence is actually incredibly unlikely because there are an enormous number of genetically possible people. You can calculate it with the number of genes and alleles, etc., and an estimate gives that there are about 10 to the power of 10,000 genetically possible people. That's between a googol and a googolplex. The number of people who have existed is 100 billion, maybe 50 billion, a tiny fraction of that. We all won this cosmic lottery. We are here. OK.

So what kind of reality do we want to live in? Do we want to live in a special reality? What if we lived in the most elegant of realities? Imagine the existential pressure that we would then have to live up to to be elegant in order not to lower the level. Or if we lived in complete reality? Then our existence would be guaranteed because all possibilities existed in this reality, but our choices would be meaningless. If I get into moral conflict and decide to do the right thing, it wouldn't matter, because there would be an infinite number of variations of me who do the right thing and an infinite number of who do the wrong thing. So it would be meaningless. So we don't want to live in this reality either. And regarding the particular reality of nothingness, then we wouldn't be having this conversation. So I think living in an unspecific reality, where there are beautiful and hideous things and we can make the beautiful things bigger and the hideous ones smaller, gives us a purpose in life. The universe is absurd, but we can still construct a purpose, and the overwhelming mediocrity of reality nicely aligns with the mediocrity we all feel deep inside. I know you feel that. You're all special, but you're still kind of secretly mediocre, aren't you? (Laughter) (applause)

In any case, you might say this riddle, the mystery of existence, is just silly secrecy. You are not amazed at the existence of the universe, and you are not the only one. Bertrand Russel said: "I would say that the universe is just there and that is all." That is a clear fact. My professor at Columbia, Sidney Morgenbesser, a great philosophical prankster, answered my question: "Professor Morgenbesser, why is there something instead of nothing?", "Oh, even if there was nothing, you would still not be satisfied."

So - (laughter) - okay. So you are not amazed. I do not care. But I'm going to finish by telling you something that is guaranteed to astonish you because it amazed all the brilliant, wonderful people I met at this TED conference when I told you, and that is: I have in mine Never owned a cell phone in my entire life. Many Thanks. (Laughter) (applause)