[Script Info]
Title: 
[Events]
Format: Layer, Start, End, Style, Name, MarginL, MarginR, MarginV, Effect, Text
Dialogue: 0,0:00:07.19,0:00:08.46,Default,,0000,0000,0000,,Time.
Dialogue: 0,0:00:10.61,0:00:11.96,Default,,0000,0000,0000,,Time does not exist.
Dialogue: 0,0:00:11.96,0:00:15.60,Default,,0000,0000,0000,,I have 15 minutes to convince you of it.
Dialogue: 0,0:00:19.48,0:00:21.62,Default,,0000,0000,0000,,Take two watches.
Dialogue: 0,0:00:23.17,0:00:26.92,Default,,0000,0000,0000,,Hopefully better than these old-fashioned\Npocket watches of my grandfather.
Dialogue: 0,0:00:26.92,0:00:28.45,Default,,0000,0000,0000,,A bit more precise, okay?
Dialogue: 0,0:00:28.45,0:00:32.06,Default,,0000,0000,0000,,Make sure that they show the same time.
Dialogue: 0,0:00:32.16,0:00:35.10,Default,,0000,0000,0000,,They show the same time, the same as here,
Dialogue: 0,0:00:35.10,0:00:37.42,Default,,0000,0000,0000,,around 2:45.
Dialogue: 0,0:00:39.60,0:00:42.98,Default,,0000,0000,0000,,Now, try raising one of them\Nand lowering the other.
Dialogue: 0,0:00:44.67,0:00:47.05,Default,,0000,0000,0000,,Keep them like that for a while:
Dialogue: 0,0:00:47.05,0:00:49.05,Default,,0000,0000,0000,,one, two, three.
Dialogue: 0,0:00:49.52,0:00:51.70,Default,,0000,0000,0000,,Then bring them back together
Dialogue: 0,0:00:52.52,0:00:54.44,Default,,0000,0000,0000,,and see what they show.
Dialogue: 0,0:00:56.06,0:00:58.66,Default,,0000,0000,0000,,If the watches are a little more\Nprecise than these,
Dialogue: 0,0:00:58.66,0:01:00.67,Default,,0000,0000,0000,,they no longer show the same time.
Dialogue: 0,0:01:01.30,0:01:04.96,Default,,0000,0000,0000,,The watch held higher reads faster,
Dialogue: 0,0:01:04.96,0:01:07.66,Default,,0000,0000,0000,,and the watch held lower reads slower.
Dialogue: 0,0:01:07.91,0:01:09.33,Default,,0000,0000,0000,,This is a fact.
Dialogue: 0,0:01:09.71,0:01:15.35,Default,,0000,0000,0000,,Obviously, with watches like these,\Nit's not very easy to see that.
Dialogue: 0,0:01:15.36,0:01:16.64,Default,,0000,0000,0000,,They're not precise enough.
Dialogue: 0,0:01:16.64,0:01:19.50,Default,,0000,0000,0000,,However, today there exist\Nextremely precise watches.
Dialogue: 0,0:01:19.50,0:01:20.78,Default,,0000,0000,0000,,That's one of them.
Dialogue: 0,0:01:20.78,0:01:23.37,Default,,0000,0000,0000,,It's the Boulder atomic clock in Colorado,
Dialogue: 0,0:01:23.37,0:01:27.21,Default,,0000,0000,0000,,one of those that are used to fix\Nthe official time in the United States.
Dialogue: 0,0:01:27.29,0:01:29.70,Default,,0000,0000,0000,,We have similar ones\Nin Italy, in Florence, lots.
Dialogue: 0,0:01:29.70,0:01:33.63,Default,,0000,0000,0000,,There are also smaller versions,\Nmore commercial versions,
Dialogue: 0,0:01:33.63,0:01:35.100,Default,,0000,0000,0000,,that are good enough\Nto observe this effect with.
Dialogue: 0,0:01:35.100,0:01:37.47,Default,,0000,0000,0000,,They are in small boxes.
Dialogue: 0,0:01:37.47,0:01:39.20,Default,,0000,0000,0000,,If you take one and put it low down,
Dialogue: 0,0:01:39.20,0:01:40.43,Default,,0000,0000,0000,,and put another high up,
Dialogue: 0,0:01:40.43,0:01:44.26,Default,,0000,0000,0000,,when you bring them back together again,\Nthey no longer show the same time.
Dialogue: 0,0:01:44.43,0:01:48.98,Default,,0000,0000,0000,,Time goes faster higher up,
Dialogue: 0,0:01:48.98,0:01:51.05,Default,,0000,0000,0000,,and slower lower down.
Dialogue: 0,0:01:51.14,0:01:52.36,Default,,0000,0000,0000,,It's a fact.
Dialogue: 0,0:01:52.47,0:01:53.52,Default,,0000,0000,0000,,For instance,
Dialogue: 0,0:01:53.52,0:01:57.43,Default,,0000,0000,0000,,imagine you have a twin brother,
Dialogue: 0,0:01:57.43,0:01:59.47,Default,,0000,0000,0000,,you are the same age,\Nyou grew up together.
Dialogue: 0,0:01:59.47,0:02:02.52,Default,,0000,0000,0000,,Imagine that your brother\Ngoes to live in the mountains,
Dialogue: 0,0:02:02.52,0:02:04.55,Default,,0000,0000,0000,,and you go to live by the sea.
Dialogue: 0,0:02:04.55,0:02:06.24,Default,,0000,0000,0000,,If much later you meet up again,
Dialogue: 0,0:02:06.24,0:02:09.51,Default,,0000,0000,0000,,your brother will be older,\Nand you will be younger than he.
Dialogue: 0,0:02:10.27,0:02:13.67,Default,,0000,0000,0000,,It's not just watches that are influenced
Dialogue: 0,0:02:13.67,0:02:15.72,Default,,0000,0000,0000,,by the strength\Nof the gravitational field,
Dialogue: 0,0:02:15.72,0:02:17.53,Default,,0000,0000,0000,,but all phenomena connected with time.
Dialogue: 0,0:02:17.53,0:02:21.37,Default,,0000,0000,0000,,Aging, the speed of our thoughts,\Na flower coming into bloom.
Dialogue: 0,0:02:21.51,0:02:22.51,Default,,0000,0000,0000,,Everything.
Dialogue: 0,0:02:22.62,0:02:24.12,Default,,0000,0000,0000,,A swinging pendulum.
Dialogue: 0,0:02:24.31,0:02:29.30,Default,,0000,0000,0000,,Time goes faster higher up,\Nand slower lower down.
Dialogue: 0,0:02:30.22,0:02:34.53,Default,,0000,0000,0000,,You see, when at the beginning of the 90s,
Dialogue: 0,0:02:34.53,0:02:37.95,Default,,0000,0000,0000,,the first satellites for GPS\Nwere sent into orbit,
Dialogue: 0,0:02:38.14,0:02:42.12,Default,,0000,0000,0000,,for the sat nav devices\Nwe have in our cars
Dialogue: 0,0:02:42.12,0:02:43.78,Default,,0000,0000,0000,,to tell us where we are,
Dialogue: 0,0:02:44.52,0:02:47.06,Default,,0000,0000,0000,,physicists told engineers,
Dialogue: 0,0:02:47.06,0:02:50.65,Default,,0000,0000,0000,,"Be careful, up there,\Non the satellites, time goes faster."
Dialogue: 0,0:02:50.68,0:02:55.07,Default,,0000,0000,0000,,To work, the device needs to receive\Nmessages from a satellite.
Dialogue: 0,0:02:55.12,0:02:57.14,Default,,0000,0000,0000,,On satellites, there's a clock.
Dialogue: 0,0:02:57.54,0:03:00.83,Default,,0000,0000,0000,,The clock goes faster than\Nwhat we would expect down here,
Dialogue: 0,0:03:01.13,0:03:03.20,Default,,0000,0000,0000,,so they'd need to take that into account.
Dialogue: 0,0:03:03.20,0:03:05.03,Default,,0000,0000,0000,,The engineers said, "Oh, okay."
Dialogue: 0,0:03:05.73,0:03:10.74,Default,,0000,0000,0000,,However, the entire project was, and is,\Na project of the American military.
Dialogue: 0,0:03:10.74,0:03:13.04,Default,,0000,0000,0000,,GPS is operated by the US military.
Dialogue: 0,0:03:13.04,0:03:15.93,Default,,0000,0000,0000,,So, heading up the project\Nwere American generals.
Dialogue: 0,0:03:15.93,0:03:19.01,Default,,0000,0000,0000,,The American generals were army generals.
Dialogue: 0,0:03:19.01,0:03:22.02,Default,,0000,0000,0000,,When told time goes slower,\Nfaster, etc., their response was:
Dialogue: 0,0:03:22.02,0:03:24.42,Default,,0000,0000,0000,,"Time goes slower? Faster?\NI don't believe it."
Dialogue: 0,0:03:24.54,0:03:29.18,Default,,0000,0000,0000,,So, the first satellites were sent up\Nwith a double system
Dialogue: 0,0:03:29.18,0:03:33.59,Default,,0000,0000,0000,,that could work taking or not taking\Ninto account this effect.
Dialogue: 0,0:03:34.78,0:03:38.00,Default,,0000,0000,0000,,The version that didn't take\Nthis effect into account didn't work.
Dialogue: 0,0:03:38.00,0:03:39.58,Default,,0000,0000,0000,,The GPS would not work
Dialogue: 0,0:03:39.58,0:03:42.93,Default,,0000,0000,0000,,if it didn't take into account\Nthe fact that up there time went faster.
Dialogue: 0,0:03:42.93,0:03:46.03,Default,,0000,0000,0000,,So, even the American generals\Ncould not be other than convinced
Dialogue: 0,0:03:46.03,0:03:49.71,Default,,0000,0000,0000,,that time went faster up there.
Dialogue: 0,0:03:53.71,0:03:55.16,Default,,0000,0000,0000,,What does this mean?
Dialogue: 0,0:03:56.31,0:03:58.45,Default,,0000,0000,0000,,It means time is not\Nwhat we imagine it to be.
Dialogue: 0,0:03:58.45,0:04:03.46,Default,,0000,0000,0000,,We cannot think of a unique time\Nthat flows the same everywhere.
Dialogue: 0,0:04:03.46,0:04:05.12,Default,,0000,0000,0000,,Somehow, we need to think
Dialogue: 0,0:04:05.12,0:04:08.38,Default,,0000,0000,0000,,that higher up, lower down,\Nmore to the right, more to the left,
Dialogue: 0,0:04:08.38,0:04:10.68,Default,,0000,0000,0000,,for who moves more slowly,\Nfor who moves faster,
Dialogue: 0,0:04:10.68,0:04:12.54,Default,,0000,0000,0000,,time goes at different speeds.
Dialogue: 0,0:04:12.74,0:04:14.97,Default,,0000,0000,0000,,We need to change how we see the world,
Dialogue: 0,0:04:14.97,0:04:16.88,Default,,0000,0000,0000,,from a single clock beating the time,
Dialogue: 0,0:04:16.88,0:04:19.86,Default,,0000,0000,0000,,to many clocks, each with its own time.
Dialogue: 0,0:04:20.11,0:04:23.62,Default,,0000,0000,0000,,The world is a choir of these clocks\Nthat go at different speeds.
Dialogue: 0,0:04:24.33,0:04:25.38,Default,,0000,0000,0000,,Strange and difficult.
Dialogue: 0,0:04:25.38,0:04:26.78,Default,,0000,0000,0000,,But if you think about it,
Dialogue: 0,0:04:26.78,0:04:29.90,Default,,0000,0000,0000,,it's not the first time we've changed\Nhow we see the world, is it?
Dialogue: 0,0:04:29.90,0:04:32.55,Default,,0000,0000,0000,,Is the Earth flat or round?
Dialogue: 0,0:04:32.55,0:04:35.31,Default,,0000,0000,0000,,This room, is it stationary\Nor is it moving?
Dialogue: 0,0:04:35.31,0:04:36.39,Default,,0000,0000,0000,,Stationary.
Dialogue: 0,0:04:36.39,0:04:39.53,Default,,0000,0000,0000,,No, we know it's moving,\Ntravelling very fast around the sun.
Dialogue: 0,0:04:40.32,0:04:43.27,Default,,0000,0000,0000,,(Hesitation)
Dialogue: 0,0:04:43.76,0:04:46.48,Default,,0000,0000,0000,,A swallow comes from another swallow,
Dialogue: 0,0:04:46.71,0:04:49.54,Default,,0000,0000,0000,,its mother was a swallow,\Nits grandmother, and so on,
Dialogue: 0,0:04:49.54,0:04:51.22,Default,,0000,0000,0000,,swallow, swallow, swallow.
Dialogue: 0,0:04:51.23,0:04:55.18,Default,,0000,0000,0000,,I was born from a human being,\Nwho was born from another human being,
Dialogue: 0,0:04:55.18,0:04:56.38,Default,,0000,0000,0000,,from another human being.
Dialogue: 0,0:04:56.38,0:04:59.25,Default,,0000,0000,0000,,So it's impossible I and a swallow\Nshare the same ancestors.
Dialogue: 0,0:04:59.25,0:05:00.58,Default,,0000,0000,0000,,Not the case.
Dialogue: 0,0:05:00.58,0:05:03.26,Default,,0000,0000,0000,,We and the swallows\Nhave the same, common ancestors.
Dialogue: 0,0:05:03.26,0:05:04.88,Default,,0000,0000,0000,,So, what's this all about?
Dialogue: 0,0:05:04.88,0:05:08.55,Default,,0000,0000,0000,,We tend to develop simple,\Nnatural ideas about the world
Dialogue: 0,0:05:08.55,0:05:09.95,Default,,0000,0000,0000,,that are wrong.
Dialogue: 0,0:05:10.24,0:05:12.57,Default,,0000,0000,0000,,Not because they are\Nnot adaptable to our lives.
Dialogue: 0,0:05:12.57,0:05:15.33,Default,,0000,0000,0000,,They are adaptable to our lives,\Nindeed that's the case;
Dialogue: 0,0:05:15.33,0:05:17.68,Default,,0000,0000,0000,,they refer to, are good on, our scale.
Dialogue: 0,0:05:17.68,0:05:21.34,Default,,0000,0000,0000,,They are no longer good\Nwhen we look at life,
Dialogue: 0,0:05:21.34,0:05:25.06,Default,,0000,0000,0000,,not on a scale of 10, 100 or 1,000 years,\Nbut on a scale of millions of years,
Dialogue: 0,0:05:25.07,0:05:28.90,Default,,0000,0000,0000,,or when we think about\Nwhat happens very far away,
Dialogue: 0,0:05:28.90,0:05:33.42,Default,,0000,0000,0000,,with very fast, very small,\Nor very big objects.
Dialogue: 0,0:05:33.68,0:05:39.20,Default,,0000,0000,0000,,There's an example I really like\Nand think useful in understanding time,
Dialogue: 0,0:05:39.20,0:05:40.71,Default,,0000,0000,0000,,that about high and low, right?
Dialogue: 0,0:05:42.04,0:05:44.76,Default,,0000,0000,0000,,Things fall from high to low.
Dialogue: 0,0:05:45.49,0:05:46.92,Default,,0000,0000,0000,,That is high, and this is low.
Dialogue: 0,0:05:46.92,0:05:49.97,Default,,0000,0000,0000,,It's one of the basic structures\Nof the world as we see it.
Dialogue: 0,0:05:49.97,0:05:52.73,Default,,0000,0000,0000,,We organize our world\Nin terms of high and low, right?
Dialogue: 0,0:05:52.94,0:05:55.01,Default,,0000,0000,0000,,So in the universe, there's high and low.
Dialogue: 0,0:05:55.01,0:05:58.77,Default,,0000,0000,0000,,Okay? A universal direction,\Nwhich is higher or lower.
Dialogue: 0,0:05:59.78,0:06:01.23,Default,,0000,0000,0000,,This isn't entirely true.
Dialogue: 0,0:06:01.23,0:06:03.24,Default,,0000,0000,0000,,What's high here is low in Sydney.
Dialogue: 0,0:06:03.80,0:06:07.29,Default,,0000,0000,0000,,What's more, if we leave the Earth,\Nthere's not really high and low.
Dialogue: 0,0:06:07.36,0:06:11.15,Default,,0000,0000,0000,,Astronauts, we saw the pictures,\Nthey move in any direction.
Dialogue: 0,0:06:11.60,0:06:14.93,Default,,0000,0000,0000,,The notion of high and low\Ndoesn't exist out there in the universe;
Dialogue: 0,0:06:15.35,0:06:18.21,Default,,0000,0000,0000,,it's a notion appropriate only here to us.
Dialogue: 0,0:06:18.68,0:06:22.72,Default,,0000,0000,0000,,It's convenient and useful\Nto organize phenomena around us,
Dialogue: 0,0:06:22.72,0:06:28.20,Default,,0000,0000,0000,,but it becomes useless and meaningless\Nthe moment we leave our planet
Dialogue: 0,0:06:28.20,0:06:33.95,Default,,0000,0000,0000,,and go to the moon, as our astronauts did.
Dialogue: 0,0:06:34.44,0:06:38.43,Default,,0000,0000,0000,,In all these cases, we find our simple way\Nof looking at the world is wrong,
Dialogue: 0,0:06:38.43,0:06:40.66,Default,,0000,0000,0000,,and things are a little more complicated.
Dialogue: 0,0:06:40.66,0:06:45.07,Default,,0000,0000,0000,,The nice thing is that\Nin all these cases, including time -
Dialogue: 0,0:06:45.07,0:06:47.04,Default,,0000,0000,0000,,I'm coming back to time -
Dialogue: 0,0:06:47.04,0:06:53.59,Default,,0000,0000,0000,,Nowadays, it's easy to think\Nthat the Earth is round,
Dialogue: 0,0:06:53.59,0:06:56.49,Default,,0000,0000,0000,,and that outside of it\Nthere's no high or low.
Dialogue: 0,0:06:57.01,0:07:00.59,Default,,0000,0000,0000,,We've seen the pictures taken\Nby the astronauts of Apollo 11
Dialogue: 0,0:07:00.59,0:07:01.99,Default,,0000,0000,0000,,on their way to the moon.
Dialogue: 0,0:07:01.99,0:07:03.60,Default,,0000,0000,0000,,The Earth is round.
Dialogue: 0,0:07:03.60,0:07:05.67,Default,,0000,0000,0000,,But we knew that before.
Dialogue: 0,0:07:05.67,0:07:09.06,Default,,0000,0000,0000,,Some of us already knew\Nthat the Earth was round, right?
Dialogue: 0,0:07:09.08,0:07:14.23,Default,,0000,0000,0000,,Aristotle knew, Anaximander knew\Nthat the Earth was round and flew.
Dialogue: 0,0:07:14.70,0:07:15.91,Default,,0000,0000,0000,,The Earth is moving.
Dialogue: 0,0:07:15.96,0:07:18.31,Default,,0000,0000,0000,,Now we've seen it from beyond it,
Dialogue: 0,0:07:18.31,0:07:22.84,Default,,0000,0000,0000,,but Galileo and Copernicus deduced it\Nwithout needing to see it.
Dialogue: 0,0:07:24.45,0:07:27.73,Default,,0000,0000,0000,,Darwin didn't see\Nspecies change; he deduced it.
Dialogue: 0,0:07:27.73,0:07:29.33,Default,,0000,0000,0000,,How did they deduce these things?
Dialogue: 0,0:07:29.33,0:07:33.50,Default,,0000,0000,0000,,Simply by starting\Nwith what we know about the world,
Dialogue: 0,0:07:33.50,0:07:36.15,Default,,0000,0000,0000,,observing, and putting\Ntogether known facts,
Dialogue: 0,0:07:36.15,0:07:40.75,Default,,0000,0000,0000,,and noticing that the known facts\Ncan be better understood
Dialogue: 0,0:07:40.75,0:07:43.35,Default,,0000,0000,0000,,if we change our conception\Nof the structure of,
Dialogue: 0,0:07:43.35,0:07:45.11,Default,,0000,0000,0000,,our way of looking at, the world.
Dialogue: 0,0:07:45.11,0:07:49.25,Default,,0000,0000,0000,,In this way, all these people came\Nto understand something new,
Dialogue: 0,0:07:49.25,0:07:50.66,Default,,0000,0000,0000,,something crucial.
Dialogue: 0,0:07:51.90,0:07:58.85,Default,,0000,0000,0000,,The fact that time goes\Nslower lower down and faster higher up,
Dialogue: 0,0:07:58.85,0:08:00.41,Default,,0000,0000,0000,,that we nowadays observe:
Dialogue: 0,0:08:00.41,0:08:05.07,Default,,0000,0000,0000,,we just need to buy\Nthose very precise clocks,
Dialogue: 0,0:08:05.07,0:08:07.26,Default,,0000,0000,0000,,and anyone can see it's the case.
Dialogue: 0,0:08:07.58,0:08:10.40,Default,,0000,0000,0000,,It was understood before it was observed,
Dialogue: 0,0:08:10.42,0:08:11.82,Default,,0000,0000,0000,,by Einstein,
Dialogue: 0,0:08:11.82,0:08:15.91,Default,,0000,0000,0000,,almost 100 years ago,\N97 years ago, in 1915,
Dialogue: 0,0:08:15.91,0:08:21.87,Default,,0000,0000,0000,,who was simply trying to clarify the ideas\Nof the physics of the world of his day.
Dialogue: 0,0:08:22.23,0:08:28.71,Default,,0000,0000,0000,,On one hand, Einstein had Newton's theory,\Nthe great theories of mechanics;
Dialogue: 0,0:08:28.71,0:08:30.55,Default,,0000,0000,0000,,on the other, he had electromagnetism.
Dialogue: 0,0:08:30.55,0:08:33.66,Default,,0000,0000,0000,,Endeavouring to combine these two things
Dialogue: 0,0:08:33.66,0:08:36.40,Default,,0000,0000,0000,,in order to have\Na coherent picture of the world,
Dialogue: 0,0:08:36.40,0:08:39.78,Default,,0000,0000,0000,,he realized that time doesn't go\Nat the same rate for everyone,
Dialogue: 0,0:08:39.78,0:08:43.19,Default,,0000,0000,0000,,that there are many different times,\Nthat time goes at different rates.
Dialogue: 0,0:08:43.42,0:08:44.80,Default,,0000,0000,0000,,This was 100 years ago.
Dialogue: 0,0:08:45.39,0:08:48.52,Default,,0000,0000,0000,,The same thing is happening today.
Dialogue: 0,0:08:48.80,0:08:51.24,Default,,0000,0000,0000,,Because, today, we are again\Nin the same situation.
Dialogue: 0,0:08:51.24,0:08:55.46,Default,,0000,0000,0000,,Today, we have the great inheritance\Nof Einstein's very beautiful theories,
Dialogue: 0,0:08:55.46,0:08:58.17,Default,,0000,0000,0000,,which, for a century,\Nwe have discovered work perfectly.
Dialogue: 0,0:08:58.17,0:08:59.93,Default,,0000,0000,0000,,We have confirmed them,
Dialogue: 0,0:08:59.93,0:09:01.79,Default,,0000,0000,0000,,we've seen there are black holes, etc.
Dialogue: 0,0:09:01.79,0:09:05.51,Default,,0000,0000,0000,,Alongside it, throughout the 20th century,\Nquantum mechanics was advancing.
Dialogue: 0,0:09:05.51,0:09:10.08,Default,,0000,0000,0000,,This morning we heard Marco telling us\Nabout the world of particle physics,
Dialogue: 0,0:09:10.09,0:09:13.28,Default,,0000,0000,0000,,all in terms of quantum mechanics,\Nan outstanding theory of motion,
Dialogue: 0,0:09:13.28,0:09:17.35,Default,,0000,0000,0000,,but which doesn't work well\Nwith Einstein's theories,
Dialogue: 0,0:09:17.35,0:09:19.01,Default,,0000,0000,0000,,with general relativity.
Dialogue: 0,0:09:19.01,0:09:24.73,Default,,0000,0000,0000,,So science tried once again\Nwith endeavors
Dialogue: 0,0:09:24.73,0:09:27.100,Default,,0000,0000,0000,,to use what we know\Nto try to gain greater insight.
Dialogue: 0,0:09:28.43,0:09:33.38,Default,,0000,0000,0000,,In 1963, two brilliant America scientists,
Dialogue: 0,0:09:33.38,0:09:36.72,Default,,0000,0000,0000,,Joe Wheeler, the man\Nin the black and while photo,
Dialogue: 0,0:09:36.72,0:09:39.39,Default,,0000,0000,0000,,and Bryce DeWitt, the man\Nin the color photo,
Dialogue: 0,0:09:39.39,0:09:42.08,Default,,0000,0000,0000,,simply took Einstein's\Ngeneral relativity equation,
Dialogue: 0,0:09:42.08,0:09:43.41,Default,,0000,0000,0000,,Einstein's theories,
Dialogue: 0,0:09:43.41,0:09:45.02,Default,,0000,0000,0000,,and quantum mechanics,
Dialogue: 0,0:09:45.02,0:09:47.46,Default,,0000,0000,0000,,and put them together\Nand wrote an equation
Dialogue: 0,0:09:47.46,0:09:51.02,Default,,0000,0000,0000,,that Wheeler called "DeWitt's Equation,"\Nand Dewitt "Wheeler's Equation,"
Dialogue: 0,0:09:51.02,0:09:54.11,Default,,0000,0000,0000,,and everyone else, a bit fed up,\N"Wheeler-DeWitt's Equation."
Dialogue: 0,0:09:54.84,0:09:58.43,Default,,0000,0000,0000,,It's that one there,\Nbut I won't go into details.
Dialogue: 0,0:09:58.72,0:10:01.14,Default,,0000,0000,0000,,An equation that to start with\Nwas very confusing.
Dialogue: 0,0:10:01.14,0:10:04.07,Default,,0000,0000,0000,,It was studied a lot,\Nand today we continue to study it.
Dialogue: 0,0:10:04.07,0:10:06.12,Default,,0000,0000,0000,,Today, the theory has been developed,
Dialogue: 0,0:10:06.14,0:10:08.14,Default,,0000,0000,0000,,and we can write it more precisely,
Dialogue: 0,0:10:08.15,0:10:11.53,Default,,0000,0000,0000,,and we can better understand\Nits significance.
Dialogue: 0,0:10:11.53,0:10:12.81,Default,,0000,0000,0000,,That's what I work at.
Dialogue: 0,0:10:13.34,0:10:17.79,Default,,0000,0000,0000,,This equation has a characteristic\Nthat was stunning at the time,
Dialogue: 0,0:10:17.79,0:10:19.30,Default,,0000,0000,0000,,and left everyone open-mouthed.
Dialogue: 0,0:10:19.30,0:10:22.89,Default,,0000,0000,0000,,This equation was created putting together\Nall that we know about the world
Dialogue: 0,0:10:22.89,0:10:24.53,Default,,0000,0000,0000,,from one end to the other.
Dialogue: 0,0:10:25.02,0:10:27.93,Default,,0000,0000,0000,,It has the characteristic as follows.
Dialogue: 0,0:10:28.76,0:10:32.53,Default,,0000,0000,0000,,All equations, if you remember\Nsomething of school physics,
Dialogue: 0,0:10:32.53,0:10:36.16,Default,,0000,0000,0000,,all the important fundamental\Nequations of physics
Dialogue: 0,0:10:36.16,0:10:39.89,Default,,0000,0000,0000,,from Galileo to Newton,\NMaxwell, Einstein, and so on,
Dialogue: 0,0:10:39.89,0:10:42.49,Default,,0000,0000,0000,,they say how things change with time -
Dialogue: 0,0:10:42.49,0:10:44.21,Default,,0000,0000,0000,,back to time again -
Dialogue: 0,0:10:44.21,0:10:48.43,Default,,0000,0000,0000,,and so they all have "t," time, in them,\Nwhether it's velocity or acceleration,
Dialogue: 0,0:10:48.43,0:10:51.61,Default,,0000,0000,0000,,changes in time, there's always\Ntime in the equations.
Dialogue: 0,0:10:51.61,0:10:54.48,Default,,0000,0000,0000,,This equation here\Ndoesn't have time in it,
Dialogue: 0,0:10:54.48,0:10:58.24,Default,,0000,0000,0000,,the variable "time" has been left out,\Nit's vanished, it's not there.
Dialogue: 0,0:10:58.90,0:11:02.31,Default,,0000,0000,0000,,It's as if trying to write\Nall we know about the world,
Dialogue: 0,0:11:02.31,0:11:04.25,Default,,0000,0000,0000,,time is no longer there.
Dialogue: 0,0:11:04.25,0:11:05.70,Default,,0000,0000,0000,,What does this mean?
Dialogue: 0,0:11:06.47,0:11:10.65,Default,,0000,0000,0000,,That is what I'll try to explain\Nin the remaining four minutes.
Dialogue: 0,0:11:10.65,0:11:13.24,Default,,0000,0000,0000,,If you listen to me carefully,
Dialogue: 0,0:11:13.24,0:11:15.25,Default,,0000,0000,0000,,I hope I'll be able to make clear to you
Dialogue: 0,0:11:15.25,0:11:18.57,Default,,0000,0000,0000,,what it means to write an equation\Nto describe the world without time.
Dialogue: 0,0:11:19.02,0:11:21.100,Default,,0000,0000,0000,,Let's go back to simpler physics.
Dialogue: 0,0:11:21.100,0:11:25.20,Default,,0000,0000,0000,,The first thing that those\Nwho enroll in physics study
Dialogue: 0,0:11:25.20,0:11:28.59,Default,,0000,0000,0000,,is how a pendulum moves, for example,\Nor something else that moves.
Dialogue: 0,0:11:28.89,0:11:32.58,Default,,0000,0000,0000,,We need to describe\Nhow its position changes with time.
Dialogue: 0,0:11:33.56,0:11:37.58,Default,,0000,0000,0000,,So we need to measure the position\Nand the time with a clock, right?
Dialogue: 0,0:11:38.08,0:11:40.50,Default,,0000,0000,0000,,We look at the position\Nand what the clock reads,
Dialogue: 0,0:11:40.50,0:11:41.70,Default,,0000,0000,0000,,make a chart,
Dialogue: 0,0:11:41.70,0:11:47.13,Default,,0000,0000,0000,,and write an equation that describes\Nhow the position changes with time.
Dialogue: 0,0:11:48.72,0:11:50.60,Default,,0000,0000,0000,,But, here, we are not observing time;
Dialogue: 0,0:11:50.60,0:11:52.98,Default,,0000,0000,0000,,here, we are looking at\Nthe hand's position, right?
Dialogue: 0,0:11:54.74,0:11:56.45,Default,,0000,0000,0000,,The hand is moving,
Dialogue: 0,0:11:56.45,0:11:57.69,Default,,0000,0000,0000,,and this is moving.
Dialogue: 0,0:11:58.04,0:12:02.11,Default,,0000,0000,0000,,We're just describing\Nhow this position shifts
Dialogue: 0,0:12:02.33,0:12:05.12,Default,,0000,0000,0000,,when the hand's position shifts.
Dialogue: 0,0:12:05.34,0:12:07.82,Default,,0000,0000,0000,,And if you think about it,\Nit's what we always do.
Dialogue: 0,0:12:07.98,0:12:10.93,Default,,0000,0000,0000,,We always describe something\Nas a function of something else.
Dialogue: 0,0:12:10.93,0:12:13.83,Default,,0000,0000,0000,,Clocks are just things\Namong others that move,
Dialogue: 0,0:12:13.83,0:12:16.69,Default,,0000,0000,0000,,but that have the characteristic\Nof all moving together ...
Dialogue: 0,0:12:16.69,0:12:18.16,Default,,0000,0000,0000,,more or less all together.
Dialogue: 0,0:12:19.61,0:12:20.80,Default,,0000,0000,0000,,What does this mean?
Dialogue: 0,0:12:20.80,0:12:23.19,Default,,0000,0000,0000,,It means that we can do without time
Dialogue: 0,0:12:23.19,0:12:26.23,Default,,0000,0000,0000,,and just talk in terms of\Nhow the pendulum moves
Dialogue: 0,0:12:26.23,0:12:28.30,Default,,0000,0000,0000,,as a function of the position of the hand.
Dialogue: 0,0:12:28.57,0:12:31.99,Default,,0000,0000,0000,,Instead of saying,\N"I woke up at 8 this morning,"
Dialogue: 0,0:12:31.99,0:12:35.09,Default,,0000,0000,0000,,I could say that I woke up\Nwhen the sun was in a given position,
Dialogue: 0,0:12:35.26,0:12:38.52,Default,,0000,0000,0000,,that I started talking\Nthe moment the lights went off,
Dialogue: 0,0:12:38.52,0:12:39.73,Default,,0000,0000,0000,,and so on and so forth,
Dialogue: 0,0:12:39.73,0:12:42.44,Default,,0000,0000,0000,,with no reference to time at all.
Dialogue: 0,0:12:42.66,0:12:44.97,Default,,0000,0000,0000,,Let's take "high" and "low," for example.
Dialogue: 0,0:12:44.97,0:12:47.55,Default,,0000,0000,0000,,I could say this is high, and this is low,
Dialogue: 0,0:12:47.55,0:12:49.74,Default,,0000,0000,0000,,or I could avoid mentioning\N"high" or "low."
Dialogue: 0,0:12:49.74,0:12:52.26,Default,,0000,0000,0000,,I could say this is towards\Nthat bright light there,
Dialogue: 0,0:12:52.26,0:12:54.98,Default,,0000,0000,0000,,and this is towards\Nthe red circle underneath me.
Dialogue: 0,0:12:55.12,0:12:57.24,Default,,0000,0000,0000,,If I'm on Earth, I complicate life.
Dialogue: 0,0:12:57.24,0:13:02.05,Default,,0000,0000,0000,,But if I'm an astronaut in a capsule\Nand say to my friend,
Dialogue: 0,0:13:02.05,0:13:04.64,Default,,0000,0000,0000,,"Hey, Anderson, could you pass me\Nthat clock up there?"
Dialogue: 0,0:13:04.64,0:13:06.53,Default,,0000,0000,0000,,he'll reply, "Where's up there?"
Dialogue: 0,0:13:08.22,0:13:10.70,Default,,0000,0000,0000,,But if I say "the one towards\Nthe red mat" instead,
Dialogue: 0,0:13:10.70,0:13:12.75,Default,,0000,0000,0000,,he'll be, "Oh, the one\Ntowards the red mat."
Dialogue: 0,0:13:12.75,0:13:17.02,Default,,0000,0000,0000,,So the notion of high or low\Nis meaningless when we leave the Earth.
Dialogue: 0,0:13:17.12,0:13:20.82,Default,,0000,0000,0000,,Well, the notion of time\Nbecomes meaningless, disappears,
Dialogue: 0,0:13:20.82,0:13:22.86,Default,,0000,0000,0000,,as soon as I leave normal space
Dialogue: 0,0:13:22.86,0:13:28.34,Default,,0000,0000,0000,,and enter one where I have to use\Nquantum gravity, this equation here.
Dialogue: 0,0:13:28.51,0:13:29.77,Default,,0000,0000,0000,,And where is this space?
Dialogue: 0,0:13:29.77,0:13:32.20,Default,,0000,0000,0000,,Where things are extremely big\Nor extremely small:
Dialogue: 0,0:13:32.36,0:13:35.08,Default,,0000,0000,0000,,there where we're still without\Nclear ideas on the world.
Dialogue: 0,0:13:35.08,0:13:37.50,Default,,0000,0000,0000,,If we observe the extremely small,
Dialogue: 0,0:13:37.50,0:13:40.18,Default,,0000,0000,0000,,observe on an extremely small scale,
Dialogue: 0,0:13:40.18,0:13:43.18,Default,,0000,0000,0000,,space, space itself fluctuates, spikes,
Dialogue: 0,0:13:43.18,0:13:45.32,Default,,0000,0000,0000,,it's like a stormy sea,
Dialogue: 0,0:13:45.32,0:13:47.86,Default,,0000,0000,0000,,but what it is, is space-time\Nin the extremely small,
Dialogue: 0,0:13:47.86,0:13:49.28,Default,,0000,0000,0000,,as if time jumps.
Dialogue: 0,0:13:49.28,0:13:53.98,Default,,0000,0000,0000,,These two clocks, each weaving\Nits own path at a different speed,
Dialogue: 0,0:13:53.98,0:13:57.42,Default,,0000,0000,0000,,in the smallest of places, they go\Nforward and backward, they move, etc.
Dialogue: 0,0:13:57.54,0:13:59.63,Default,,0000,0000,0000,,On this extremely small scale,
Dialogue: 0,0:13:59.63,0:14:04.11,Default,,0000,0000,0000,,our notion of time is no longer good,\Nno longer useful, no longer works well.
Dialogue: 0,0:14:04.59,0:14:11.17,Default,,0000,0000,0000,,So we have to re-describe\Nthe world in terms of those variables,
Dialogue: 0,0:14:11.45,0:14:14.45,Default,,0000,0000,0000,,one by one, without reference to time,
Dialogue: 0,0:14:14.45,0:14:17.16,Default,,0000,0000,0000,,as if we had a lot of clocks\Nthat had lost their hands,
Dialogue: 0,0:14:17.16,0:14:21.14,Default,,0000,0000,0000,,and we could only see\Nhow one moves in respect to the other.
Dialogue: 0,0:14:21.48,0:14:25.22,Default,,0000,0000,0000,,Imagine, to give you an idea,
Dialogue: 0,0:14:25.22,0:14:28.38,Default,,0000,0000,0000,,how we think about the world\Nas a combination of things that move,
Dialogue: 0,0:14:28.38,0:14:31.08,Default,,0000,0000,0000,,that change, that dance, all together,
Dialogue: 0,0:14:31.08,0:14:32.90,Default,,0000,0000,0000,,in time to a conductor of an orchestra
Dialogue: 0,0:14:32.91,0:14:36.92,Default,,0000,0000,0000,,who gives the beat:\N1, 2, 1, 2 ... all together ... 1, 2.
Dialogue: 0,0:14:37.65,0:14:39.86,Default,,0000,0000,0000,,This picture no longer works\Nfor the small.
Dialogue: 0,0:14:39.86,0:14:44.16,Default,,0000,0000,0000,,In the extremely small,\Nthere's no unique beat for all,
Dialogue: 0,0:14:44.16,0:14:49.54,Default,,0000,0000,0000,,and the world is as if it were a dance\Nof every microelement with its neighbor,
Dialogue: 0,0:14:49.54,0:14:51.28,Default,,0000,0000,0000,,but not all together.
Dialogue: 0,0:14:53.48,0:14:56.22,Default,,0000,0000,0000,,What's the moral of this whole story?
Dialogue: 0,0:14:56.22,0:14:58.76,Default,,0000,0000,0000,,Time is a useful concept,
Dialogue: 0,0:14:58.76,0:15:00.91,Default,,0000,0000,0000,,it organizes our daily experiences,
Dialogue: 0,0:15:00.91,0:15:02.86,Default,,0000,0000,0000,,but it is not a fundamental concept.
Dialogue: 0,0:15:02.86,0:15:05.53,Default,,0000,0000,0000,,Just as "high" and "low"\Nare very useful concepts,
Dialogue: 0,0:15:05.53,0:15:09.83,Default,,0000,0000,0000,,but don't work anymore\Nwhen we leave our everyday surroundings.
Dialogue: 0,0:15:10.97,0:15:12.72,Default,,0000,0000,0000,,This is true of a lot of things.
Dialogue: 0,0:15:12.72,0:15:15.26,Default,,0000,0000,0000,,It's this that I love about science.
Dialogue: 0,0:15:15.26,0:15:18.86,Default,,0000,0000,0000,,What science teaches us\Nis that our image of the world,
Dialogue: 0,0:15:18.86,0:15:21.06,Default,,0000,0000,0000,,our perception of the world,
Dialogue: 0,0:15:21.06,0:15:23.54,Default,,0000,0000,0000,,is very often wrong, limited,
Dialogue: 0,0:15:23.54,0:15:26.04,Default,,0000,0000,0000,,working only in our usual surroundings.
Dialogue: 0,0:15:26.68,0:15:30.61,Default,,0000,0000,0000,,The human race is like\Nsomeone born in a small town
Dialogue: 0,0:15:30.61,0:15:32.47,Default,,0000,0000,0000,,where everyone behaves in the same way,
Dialogue: 0,0:15:32.47,0:15:34.76,Default,,0000,0000,0000,,until they leave and say,\N"Oh, but there's more.
Dialogue: 0,0:15:34.76,0:15:37.24,Default,,0000,0000,0000,,We can eat different things,\Nsay different things,
Dialogue: 0,0:15:37.24,0:15:39.56,Default,,0000,0000,0000,,speak different languages,\Nhave different ideas."
Dialogue: 0,0:15:39.56,0:15:44.06,Default,,0000,0000,0000,,Humanity leaves behind\Nthe smallness of its thoughts
Dialogue: 0,0:15:44.32,0:15:46.71,Default,,0000,0000,0000,,and discovers that everything's different:
Dialogue: 0,0:15:46.71,0:15:48.78,Default,,0000,0000,0000,,species transform from one to another,
Dialogue: 0,0:15:48.78,0:15:50.30,Default,,0000,0000,0000,,"high" and "low" are not real,
Dialogue: 0,0:15:50.30,0:15:51.94,Default,,0000,0000,0000,,time is not what it seems.
Dialogue: 0,0:15:51.94,0:15:57.29,Default,,0000,0000,0000,,The world is bigger, more beautiful,\Nmore diverse, and more thought-provoking
Dialogue: 0,0:15:57.29,0:15:59.83,Default,,0000,0000,0000,,than what it seems at first sight,
Dialogue: 0,0:15:59.83,0:16:02.21,Default,,0000,0000,0000,,this thing, a little banal,\Nwith "high" and "low,"
Dialogue: 0,0:16:02.21,0:16:04.27,Default,,0000,0000,0000,,with people that move,\Nand rocks that fall.
Dialogue: 0,0:16:04.27,0:16:05.52,Default,,0000,0000,0000,,It's much richer.
Dialogue: 0,0:16:05.52,0:16:09.26,Default,,0000,0000,0000,,And to understand that,\Nwe have little need of ancient knowledge.
Dialogue: 0,0:16:09.26,0:16:11.91,Default,,0000,0000,0000,,Ancient knowledge, all ancient knowledge,
Dialogue: 0,0:16:11.91,0:16:13.41,Default,,0000,0000,0000,,what our forefathers taught us,
Dialogue: 0,0:16:13.41,0:16:14.86,Default,,0000,0000,0000,,really only applies here.
Dialogue: 0,0:16:14.97,0:16:17.44,Default,,0000,0000,0000,,If we look a little further,\Nit's no longer valid.
Dialogue: 0,0:16:17.44,0:16:20.72,Default,,0000,0000,0000,,As was said in the first video today,\Nthe universe is endless.
Dialogue: 0,0:16:20.72,0:16:24.02,Default,,0000,0000,0000,,We were born in a tiny,\Nlittle corner of it,
Dialogue: 0,0:16:24.02,0:16:26.68,Default,,0000,0000,0000,,have ideas that apply\Nonly to this tiny, little corner,
Dialogue: 0,0:16:26.68,0:16:29.14,Default,,0000,0000,0000,,when we then start\Nto look a little further afield.
Dialogue: 0,0:16:29.14,0:16:32.12,Default,,0000,0000,0000,,I think what we discover at each step -
Dialogue: 0,0:16:32.12,0:16:33.65,Default,,0000,0000,0000,,and I'm concluding -
Dialogue: 0,0:16:33.65,0:16:36.83,Default,,0000,0000,0000,,is far more extensive,\Nmore beautiful, more complex,
Dialogue: 0,0:16:36.83,0:16:39.42,Default,,0000,0000,0000,,than any of the ideas\Nour forefathers told us about,
Dialogue: 0,0:16:39.42,0:16:41.35,Default,,0000,0000,0000,,or our moms and dads taught us.
Dialogue: 0,0:16:41.35,0:16:43.21,Default,,0000,0000,0000,,And this beauty that overwhelms us,
Dialogue: 0,0:16:43.21,0:16:45.45,Default,,0000,0000,0000,,this mystery that always lies before us
Dialogue: 0,0:16:45.45,0:16:48.35,Default,,0000,0000,0000,,to which we gain access,\Nstep by step, little by little,
Dialogue: 0,0:16:48.35,0:16:50.95,Default,,0000,0000,0000,,but which forever remains boundless,
Dialogue: 0,0:16:50.95,0:16:53.53,Default,,0000,0000,0000,,draws us, fascinates us,\Nand we want to get to see it.
Dialogue: 0,0:16:53.53,0:16:54.89,Default,,0000,0000,0000,,This, for me, is science.
Dialogue: 0,0:16:54.89,0:16:56.02,Default,,0000,0000,0000,,Thank you.
Dialogue: 0,0:16:56.02,0:16:58.44,Default,,0000,0000,0000,,(Applause)