00:00:00.000 We've been told to go out on a limb and say something surprising.
00:00:29.840 So I'll try and do that, but I want to start with two things that everyone already knows.
00:00:37.840 And the first one, in fact, is something that has been known for most of recorded history.
00:00:44.840 And that is that the planet Earth or the solar system or our environment or whatever is uniquely suited to sustain our evolution
00:01:01.840 And our present existence and most important, our future survival.
00:01:08.840 And nowadays, this idea has a dramatic name, Spaceship Earth.
00:01:13.840 And the idea there is that outside the Spaceship, the universe is implacably hostile.
00:01:24.840 If we mess up our Spaceship, we've got nowhere else to go.
00:01:27.840 Now, the second thing that everyone already knows is that contrary to what was believed for most of human history,
00:01:35.840 human beings are not in fact the hub of existence.
00:01:41.840 And Stephen Hawking famously said, we're just a chemical scum on the surface of a typical planet that's in orbit around a typical star,
00:01:51.840 which is on the outskirts of a typical galaxy and so on.
00:01:56.840 Now, the first of those two things that everyone knows is kind of saying that we're at a very untypical place,
00:02:06.840 And the second one is saying that we're at a typical place.
00:02:09.840 And especially if you regard these two as deep truths to live by and to inform your life decisions,
00:02:16.840 then they seem a little bit to conflict with each other.
00:02:22.840 But that doesn't prevent them from both being completely false.
00:02:41.840 Well, let's look around, you know, looking around them direction and we see a wall and a chemical scum.
00:02:56.840 All you've got to do is go a few hundred miles in that same direction and look back and you won't see any walls or chemical scum at all.
00:03:06.840 And if you go further than that, you'll see the sun, the solar system and stars and so on.
00:03:13.840 But that's not still not typical of the universe because stars come in galaxies.
00:03:18.840 And most places in the universe, a typical place in the universe is nowhere near any galaxy.
00:03:25.840 So, let's go out further till we outside the galaxy and look back and there's a huge galaxy with spiral arms laid out in front of us.
00:03:35.840 And at this point, we've come a hundred thousand light years from here.
00:03:42.840 But we're still nowhere near a typical place in the universe.
00:03:48.840 To get to a typical place, you've got to go a thousand times as far as that into intergalactic space.
00:03:59.840 What does a typical place in the universe look like?
00:04:02.840 At enormous expense, TED has arranged a high resolution immersion virtual reality rendering of intergalactic space.
00:04:14.840 So can we have the lights off please so we can see it?
00:04:25.840 But you see, an intergalactic space is intergalactic space is completely dark, pitch dark.
00:04:32.840 It's so dark that if you were to be looking at the nearest star to you, and that star were to explode as a supernova,
00:04:43.840 and you would be staring directly at it at the moment when its light reached you,
00:04:48.840 you still wouldn't be able to see even a glimmer.
00:04:56.840 And that's despite the fact that a supernova is so bright, so brilliant an event that it would kill you stone dead at a range of several light years.
00:05:08.840 And yet, from intergalactic space, it's so far away, you wouldn't even see it.
00:05:13.840 It's also very cold out there, less than three degrees above absolute zero.
00:05:19.840 And it's very empty. The vacuum there is one million times less dense than the highest vacuum that our best technology on Earth can currently create.
00:05:30.840 So that's how different a typical place is from this place, and that is how untypical this place is.
00:05:40.840 So can we have the lights back on please? Thank you.
00:05:45.840 Now, how do we know about an environment that's so far away and so different and so alien from anything we're used to?
00:05:53.840 Well, the Earth, our environment in the form of us, is creating knowledge.
00:05:59.840 Well, what does that mean? Well, look out of even further than we've just been, I mean from here with the telescope.
00:06:06.840 And you'll see things that look like stars, they're called quesars.
00:06:10.840 Quesars originally meant quasi-stellar object, which means things that look a bit like stars.
00:06:17.840 But they're not stars, and we know what they are.
00:06:23.840 Billions of years ago, and billions of light years away, the material at the center of a galaxy collapsed towards a supermassive black hole.
00:06:33.840 And then intense magnetic fields directed some of the energy of that gravitational collapse and some of the matter.
00:06:41.840 Back out in the form of tremendous jets, which illuminated lobes with the brilliance of I think it's a trillion suns.
00:06:50.840 Now, the physics of the human brain could hardly be more unlike the physics of such a jet.
00:06:58.840 We couldn't survive for an instant in it, the language breaks down when trying to describe what it would be like in one of those jets.
00:07:06.840 It would be a bit like experiencing a supernova explosion, but at point blank range and for millions of years at a time.
00:07:16.840 And yet that jet happened in precisely such a way that billions of years later on the other side of the universe,
00:07:26.840 some bit of chemical scum could accurately describe and model and predict and explain, above all, there's your reference.
00:07:40.840 The one physical system, the brain, contains an accurate working model of the other, the quasar.
00:07:47.840 Not just a superficial image of it, though it contains that as well, but an explanatory model.
00:07:53.840 And embodying the same mathematical relationships and the same causal structure.
00:08:01.840 And if that weren't amazing enough, the faithfulness with which the one structure resembles the other is increasing with time.
00:08:12.840 The laws of physics have this special property that physical objects, as unlike each other as they could possibly be, can nevertheless embody the same mathematical and causal structure and to do it more and more so over time.
00:08:36.840 It structure contains, with ever increasing precision, the structure of everything, this place and not other places in the universe is a hub, which contains within itself the structural and causal essence of the whole of the rest of physical reality.
00:08:54.840 And so far from being insignificant, the fact that the laws of physics allow this or even mandate that this can happen is one of the most important things about the physical world.
00:09:07.840 Now, how does the solar system in our environment in the form of us acquire this special relationship with the rest of the universe?
00:09:16.840 Well, one thing that is true about Stephen Hawking's remark, it is true, but it is the wrong emphasis.
00:09:25.840 One thing that is true about it is that it doesn't do it with any special physics.
00:09:31.840 There is no special dispensation, no miracles involved.
00:09:34.840 It does it simply with three things that we have here in abundance.
00:09:38.840 One of them is matter because, well, the growth of knowledge is a form of information processing, information processing is computation, computation requires a computer.
00:09:49.840 There is no known way of making a computer without matter.
00:09:52.840 We also need energy to make the computer and most important to make the media in effect on which we record the knowledge that we discover.
00:10:01.840 And then, thirdly, less tangible, but just as essential for the open-ended creation of knowledge of explanations is evidence.
00:10:12.840 Now, our environment is inundated with evidence.
00:10:17.840 We happen to get around to testing, let's say, Newton's Law of Gravity about 300 years ago.
00:10:24.840 But the evidence that we used to do that was falling down on every square meter of the earth for billions of years before that, and we'll continue to fall on the billions of years afterwards.
00:10:36.840 And the same is true for all the other sciences.
00:10:39.840 As far as we know, evidence to discover the most fundamental truths of all the sciences is here just for the taking on our planet.
00:10:48.840 Our location is saturated with evidence and also with matter and energy.
00:10:53.840 Out in intergalactic space, those three prerequisites for the open-ended creation of knowledge are at their lowest possible supply.
00:11:01.840 As I said, it's empty, it's cold, and it's dark out there.
00:11:08.840 Now, actually, that's just another parochial misconception, because imagine a cube out there in intergalactic space, the same size as our home, the solar system.
00:11:21.840 Now, that cube is very empty by human standards, but that still means that it contains over a million tons of matter.
00:11:29.840 And a million tons is enough to make, say, a self-contained space station on which there's a colony of scientists that are devoted to creating an open-ended stream of knowledge and so on.
00:11:41.840 Now, it's way beyond present technology to even gather the hydrogen from intergalactic space and form it into other elements and so on.
00:11:50.840 But the thing is, in a comprehensible universe, if something isn't forbidden by the laws of physics, then what could possibly prevent us from doing it other than knowing how?
00:12:02.840 In other words, it's a matter of a knowledge, not resources.
00:12:06.840 And the same, well, if we could do that, we'd automatically have an energy supply because this transmutation would be a fusion reactor.
00:12:13.840 And evidence, well, again, it's dark out there to human senses, but all you've got to do is take a telescope, even one of present-day design.
00:12:22.840 Look out and you'll see the same galaxies as we do from here.
00:12:26.840 And with a more powerful telescope, you'll be able to see stars and planets in those galaxies.
00:12:32.840 You'll be able to do astrophysics and learn the laws of physics, and locally there you could build particle accelerators and learn elementary particle physics and chemistry and so on.
00:12:41.840 Probably the hardest science to do would be biology field trips, because it would take several hundred million years to get to the nearest life-bearing planet and back.
00:12:53.840 But I have to tell you, and sorry, Richard, but I never did like biology field trips much, and I think we can just about make-do with one every few hundred million years.
00:13:06.840 So, in fact, intergalactic space does contain all the prerequisites for the open-ended creation of knowledge.
00:13:16.840 Any such cube anywhere in the universe could become the same kind of hub that we are, if the knowledge of how to do so were present there.
00:13:29.840 So, we're not in a uniquely hospitable place. If intergalactic space is capable of creating an open-ended stream of explanations, then so is almost every other environment, so is the earth, so is a polluted earth.
00:13:44.840 And the limiting factor there and here is not resources because they're plentiful, but knowledge, which is scarce.
00:13:53.840 Now, this cosmic knowledge-based view may, and I think ought to, make us feel very special, but it should also make us feel vulnerable because it means that without the specific knowledge that's needed to survive the ongoing challenges of the universe, we won't survive them.
00:14:13.840 All it takes is for supernova to go off a few light years away, and we'll all be dead. Martin Reese has recently written a book about our vulnerability to all sorts of things from astrophysics, to scientific experiments gone wrong, and most importantly, to terrorism with weapons of mass destruction.
00:14:32.840 And he thinks that civilization has only a 50% chance of surviving this century. I think he's going to talk about that later in the conference.
00:14:40.840 Now, I don't think that probability is the right category to discuss this issue in, but I do agree with him about this. We can survive, and we can fail to survive, but it depends not on chance, but on whether we create the relevant knowledge in time.
00:15:00.840 The danger is not at all unprecedented. Species go extinct all the time. Civilizations end. The overwhelming majority of all species and all civilizations that have ever existed are now history, and if we want to be the exception to that, then logically, our only hope is to make use of the one feature that distinguishes our species and our civilization from all the others,
00:15:28.840 namely our special relationship with the laws of physics, our ability to create new explanations, new knowledge to be a hub of existence.
00:15:40.840 So let me now apply this to a current controversy, not because I want to advocate any particular solution, but just to illustrate the kind of thing I mean.
00:15:50.840 The controversy is global warming. Now, I'm a physicist, but I'm not the right kind of physicist in regard to global warming, I'm just a layman.
00:15:59.840 And the rational thing for a layman to do is to take seriously the prevailing scientific theory.
00:16:06.840 And according to that theory, it's already too late to avoid a disaster, because if it's true that our best option at the moment is to prevent CO2 emissions with something like the Kyoto protocol
00:16:19.840 strains on economic activity and its enormous cost of hundreds of billions of dollars or whatever it is, then that is already a disaster by any reasonable measure.
00:16:31.840 And the actions that advocated are not even purported to solve the problem, merely to postpone it by a little.
00:16:38.840 So it's already too late to avoid it, and it probably has been too late to avoid it ever since before anyone realized the danger. It was probably already too late in the 1970s when the best available scientific theory was being us, that industrial emissions were about to precipitate a new ice age in which billions would die.
00:16:59.840 Now, the lesson of that seems clear to me, and I don't know why it isn't informing public debate. It is that we can't always know.
00:17:08.840 When we know of an impending disaster and how to solve it at a cost less than the cost of the disaster itself, then there's not going to be much argument really.
00:17:18.840 But no precautions and no precautionary principle can avoid problems that we do not yet foresee, hence we need a stance of problem fixing, not just problem avoidance.
00:17:35.840 And it's true that an ounce of prevention equals a pound of cure, but that's only if we know what to prevent.
00:17:42.840 If you've been punched on the nose, then the science of medicine does not consist of teaching you how to avoid punches.
00:17:50.840 If medical science stopped seeking cures and concentrated on prevention only, then it would achieve very little of either.
00:17:58.840 The world is buzzing at the moment with plans to force reductions in gas emissions at all costs. It ought to be buzzing with plans to reduce the temperature and with plans to live at the higher temperature, and not at all costs, but efficiently and cheaply.
00:18:16.840 As such plans exist, things like swarms of mirrors in space to deflect the sunlight away and encouraging aquatic organisms to eat more carbon dioxide. At the moment, these things are fringe research. They're not central to the human effort to face this problem or problems in general.
00:18:34.840 And with problems that we are not aware of yet, the ability to put right, not the sheer good luck of avoiding indefinitely, is our only hope not just of solving problems but of survival.
00:18:48.840 Take two stone tablets and carve on them on one of them, carve problems are soluble. And on the other one, carve problems are inevitable. Thank you.
00:19:12.840 What if great ideas weren't cherished? What if they carried no importance? Or held no value?
00:19:29.840 There is a place where artistic vision is protected, where inspired design ideas live on to become ultimate driving machines.
