I tell you, no matter how much you may like to go Swiss air, one thing you can't call the experience
is a ‘flight of fancy’: Nothing so irrational. But, efficient? Yes.
You know their boast: if you want to the right time, you set your watch by one of their touchdowns.
Still, what would you expect from a nation of clockmakers?
Even the trams run on time. They are a tick-tock lot, the Swiss.
I mean, look around, life here is logical, orderly, efficient.
They obey the law, because the discipline it imposes on the community makes it organised enough
to achieve one of the highest standards of living in the entire world.
All you need here is money.
The view they take here, though, is, if you think about it, the epitome
of what the modern scientific world we live in is supposed to be about.
Cool, rational, common sense.
With science to explain everything because ultimately everything is knowable,
there is nowhere to go but onwards and upwards.
It is an attitude we inherited and nobody took to it more enthusiastically than the Swiss.
About 300 years ago. From Newton. You know? That the universe, and everything in,
it runs like a giant clock. With God, the great timekeeper in the sky.
It is 1801,
and in Geneva a visiting Italian is, although he doesn't know it,
about to trigger the destruction of the universe. With a box he is taking to a party.
Being a Swiss party of course, it is a hair-raisingly serious affair.
Today’s shocking display, ho, ho: all you ever wanted to know about electricity.
All they know about electricity, of course, is ‘not much’.
A mystery force that goes through people who hold hands and makes sparks.
Electricity also attracts some things and repels others and apparently the way electrically charged things
do attract and repel each other happens in straight lines and depends on how far apart they are,
just like Newton said everything should.
Good old Newton, always right.
Meanwhile, enter our Italian Giuseppe Voltaire with his pal Brugnatelli,
on their way to see Napoleon after a brief stopover to galvanise Genevan society with this.
Voltaire’s pile of copper and wet pasteboard disks that, would you believe it, makes non-stop electricity,
as long as you keep it damp.
And the destruction of the universe? The pile would spark that off.
Voltaire’s pile caused sparks in more ways than one,
because it immediately set the public and the scientists off in that direction.
With the public heading for the wonder technology it has mistakenly taken science to be ever since.
Like arcing for instance. The same year as that demo back in Geneva,
Humphrey Davy in England was sparking current between two carbon rods,
producing a brilliant white flash and turning the world on to the electric light.
Military gents started exploding mines remotely,
and medical quacks gave shock treatment for everything from infertility to drowning.
Voltaire’s pal, Brugnatelli explored the mysteries of electrolysis.
Put the leads from a pile into a solution, say, of salt, sodium chloride,
and it splits into sodium metal and chlorine gas: great technique for extracting metals,
or in Brugnatelli's case who was coining it depositing gold from a solution onto medallions.
‘Electroplating’, that: turned out great for the table setting business.
Meanwhile, the scientists were going off the rails.
Mysterious things were happening because, although chemistry could be caused by electricity:
electrolysis, it could also happen the other way round.
A solution, like lead acid, could produce a current.
So, was there some connection between electricity and chemistry?
Interesting train of thought, that.
And it fitted the romantic ideas of the time with social misfits like Byron and Shelley
fetching up here at the Castle of Chillon to write second-rate poems about the
lonely grandeur of the Alps and all that back-to-nature stuff, because the philosophy behind their efforts
was called “nature philosophy”.
It had to do with everything in existence being the product of two conflicting forces
that resolve themselves into a higher unity. After conflicting first, you understand.
All very mystic stuff,
but you can see how that kind of thinking would leap at any new example of a force like electricity,
to see if it would conflict with anything else around.
And one thing those loony Romantics had noticed was how very easy it was to get lost in these parts,
as lightning caused your compass needle to go haywire while you wandered lonely as a cloud,
getting totally sodden in Alpine storms. Speaking of which…
That's better.
Speaking of which, as I said, in 1820, an immensely boring Dane called Oersted,
during a lecture in Copenhagen, applied the basic nature philosophy idea of conflicting forces
and decided that if he forced the force, electricity, by shoving it down a high resistance wire,
the wire, with all the effort, would go incandescent. Like lightning was.
And, since lightning made compass needles go funny,
he thought if he brought
a needle close to his wire, something philosophically meaningful should happen. Shouldn’t it?
Sure enough, something did. The compass needle went, so to speak, wild.
And it did it even when separated from the wire by wood, water, glass, metal,
anything friend Oersted could think of.
And it did it all round the wire in a uniform, circular manner.
Even though Newton said everything acted in straight lines.
The electricity in the wire was obviously giving off something strange that affected the magnetic needle.
Electricity was setting up some kind of magnetic field. Now there was only one minor awkwardness about that.
It was supposed to be impossible. For a start, “what was the field?” And for a finish, “how did it work?”
And for a second finish, “in what?”
One year later another intense nature philosophy-person called Faraday
was trying to answer the questions Oersted had left in the air.
An electric wire would generate a magnetic force that actually made a floating magnet circle it.
So Faraday reckoned the opposite ought to happen. Sure enough, it did.
Faraday got turned on by the thought that if an electric current made a magnetic field,
maybe a magnetic field would make an electric current.
He set up a compass needle to detect the current if it was there.
It wasn't.
Except when he switched the magnetic field on and off.
So it was a changing field that did it.
Well, there was an easier way to put a changing magnetic field near a wire.
Push a magnet in and out of a coil, so that was it, just moving the magnet made surges of current in the wire.
You could see the current, the needle swung. But why had moving a magnet made electricity?
Then he got it, when you moved the magnet, the wire cut through its magnetic force lines.
In 1831, Faraday was cutting magnetic force lines with a spinning copper disk
and making electricity happen in the disk as long as you cared to turn the handle.
Well, before the public could begin to ponder the philosophic implications of Faraday's
deeply meaningful discoveries, here in the United States, they had once again been hijacked by the glitter
of technology.
As assorted American blacksmiths, travelling dentists, civil servants, and other such riff-raff
dazzled the eye and numbed the brain
with the latest mechanical marvels.
Basically, this avalanche of electromagnetic gizmos, seen here in model form, came in two types.
This lot used the ability to switch on and off the magnetic effect of a current,
to attract a piece of metal up and down, or, back and forth.
Most of them linked the movement to a flywheel.
And this one drove machine belts in a factory. And so on.
The other wonder machine in this electromagnetic extravaganza used the other effect.
The way a moving magnet will make current in a wire. Here is the moving magnet:
here is the power.
This beautiful looking thing would one day lead to electricity generators.
And these little whizzers, as you will already have guessed, did pave the way to real electric motors.
All good knockout stuff.
But for sending the public right off on the wrong track about science, in 1844, nothing equalled this magic sound.
The morse key interrupted a current going down a wire and made a magnet turn on and off at the other end.
Morse code united the United States.
Meanwhile, back in Cambridge, the study of how electromagneticism actually worked
seemed to be leading scientists right up the creek.
You see, for 200 years, Newton's version of the universe had explained absolutely everything
According to him, the universe was made up of bits of matter surrounded by empty space.
And force interacted between the bits, like gravity.
And the force was supposed to go in straight lines, you remember,
and act instantaneously through empty space from one bit to another.
Well, electricity wasn't doing any of that, the force lines were curved.
It was in space, and not in the wire or the magnets
and, as for going instantaneously through empty space, was it empty?
Not according to a guy called Young, who had looked at light, and found that it acted like this.
Like ripples. Two sets of ripples moving outwards, here they are. Meet and interact like this, don't they?
Some waves meet and boost each other, the light bands, others cancel each other out, the dark bands.
So, did light act like ripples?
If you try it with light going through two holes and then meeting and interacting,
you get the same effect.
You see those light and dark bands? Interfering waves of light.
Now, the reason Young's idea was dynamite was if that light did travel in waves,
it wasn't instantaneous, it took time. And, it had to be waves in something.
He called the something ‘ether’.
Out there, in here, everywhere in the universe, invisible stuff, making waves.
And maybe, also carrying electricity and magnetism.
It would certainly give Faraday's lines of force a place to be, but it would also blow Newton's idea of ‘empty space’
right out window.
So, the fellow who did that, in 1861, a Scottish Faraday fan called Maxwell, here in Trinity College Cambridge,
began with caution.
First, he made himself a mental model of these mysterious ether forces
and imagined them to act like fluids, because you could measure what fluids did.
A cross-section of what was in Maxwell's mind, might have looked something like this.
The idea, and it was pretty weird, was,
tubes of invisible magnetic force, surrounded by spinning cylinders of ether.
The faster the ether spins, the more intense the magnetism. Well, I said it was weird.
Electricity?
He made that, little balls of ether, a current would be moving balls.
And magnetism could move balls and make electricity or vice versa.
Typically complicated bit of Victoriana.
Now, the figures Maxwell got from his mental model, told him that if,
when the lines of force first came into existence, say, in a live wire,
and then radiated out to take up position around, they should radiate at a certain speed.
Almost exactly the speed of light.
Although he had no proof, Maxwell jumped in with both feet.
“You will see,” he said, “electricity, magnetism and light are all one wave, moving through the ether”.
Goodbye Newton? Well, nobody could test Maxwell's theory,
so now the scientists were going that way.
To a public whose knowledge of science was rising to zero,
one man, more than any other, was to stamp the image of the tireless
scientific genius at work for the betterment of mankind on their consciousness for ever.
Because he made sure of his PR. Thomas A. Edison, inventor extraordinaire.
In this laboratory here,
he filed no less than 1039 patents. You are looking at the world's first inventions factory.
Well, more of a shrine really. Henry Ford was so taken with Edison,
that he moved this lot lock, stock and the tree outside, all the way from New Jersey to this museum here, outside Detroit.
All to the memory of a man who must have been absolutely insufferable.
Edison used to say, “I can never pick something up without want wanting to improve it”.
Except he didn't. Fifteen loyal and very unknown specialists worked very behind the scenes
to obey his pleasant little rule of life. “If there's a better way, find it”
He, himself, worked to a set of rules: One, get the money first, two, find the market, three,
(only after one and two), produce the goods.
He reckoned to turn out a minor invention every ten days and something big every six months.
Modest, no? But, the stuff in this hallowed spot did somewhat knock the world for six, it must be said,
like, the phonograph.
Mary had a little lamb, its fleece was white as snow, and everywhere that Mary went,
the lamb was sure to go
The repeating telegraph.
The electric sewing machine.
The electric pen.
And, perhaps the most illuminating example of why the public was led by the nose into taking technology to be science,
the light bulb.
Bingo!
Well it would have been bingo if you had never seen it before, wouldn't it?
It took him two years and 6000 tries to get the right filament inside that bulb.
Well, it took his loyal sidekicks two years and 6000 tries etc.
Hello? I would like to call England please. Another one of his inventions.
The year after Edison lit up, an American living in London was to show an amazing discovery
concerning electromagnetic force to local scientific big-wigs.
This clockwork bit automatically breaks an electric circuit for a split second, at regular intervals.
Several hundred yards away from the clockwork, out in the garden, the American: a music professor called Hughes.
This is Hughes, and this is his discovery.
When the circuit back in the house gets broken,
you can hear a noise in a telephone receiver, if it is attached to a battery via a loose contact
because, Hughes reckons, the loose contact is being zapped
by waves of electromagnetic energy, coming from the short circuiting spark indoors.
But, the waves aren’t coming through a wire, they are wireless waves, get it?
Well the bumbling British boffin doesn't.
There they are, at the far side of the lake, Sir
Yes, I see
Alas, for poor old Hughes, the demonstration was a flop. All the credit went to a German, seven years later.
The English just couldn't believe what they were hearing.
Mysterious air waves travelling hundreds of yards. Harrumph!
Induction
Well, the technology freaks really had a field day a bit later on,
when the transmission range went up to 4000 miles because of a fellow called Marconi
who also found a way to use the mysterious waves, called radio.
The trouble was, now everybody was happily making waves the question still remained
“what were the waves travelling in?” “What was the, so called, ‘ether’?”
And why couldn't anybody ever find it, to answer that question?
Well, in 1887, a couple of people here in America decided to have a crack at finding out,
by shooting light beams through the ether in different directions.
Let me give you their reasoning: Suppose this boat I’m on is the Earth,
travelling through the ether of space, say, at 5 miles an hour.
If I shoot a light beam ahead at 6 miles an hour, let's say the beam is that boat there,
it will creep ahead and leave me behind at 1 mile an hour, the difference in our speeds.
So, it will take quite a while to get, say, half a mile ahead.
At that point when it turns round, of course, our combined speeds will bring us back together again fast.
But, if at the same time I send another light beam, that boat,
at the same speed as the other one, 6 miles an hour, sideways to me, the same distance out and back,
he will get back sooner. Look. Go.
See how the sideways beam is moving off quite fast relative to me? Getting to the half-mile point quickly?
And the beam pushing out ahead is going to take longer because, relative to me,
it is only doing 1 mile an hour.
The sideways beam is already turning back.
Now, if real light beams did that, it would be proof that the ether existed.
And you could measure the ether through what it was doing to the light beams.
Those two Americans I was talking about, Michelson and Morley, did this great experiment here,
Cleveland, at the University. Do you remember Young and the light waves and stuff and those
interference patterns you get when light waves mix when they are out of phase?
These light and dark bands, here? This is the trick they used
to see one light beam returning sooner than the other.
Come on, I will show you.
Okay, let's take it that this lecture hall and the Earth are going through space, well they had better be,
that way. So that is straight ahead. Here is the light source.
Send the beam out and split it with this half-mirror.
One half of the beam goes that way, you remember that is the straight-ahead direction,
and the other half of the beam goes this way, out to the side.
Now, you give the beams a nice long trip by bouncing them back and forward between these mirrors for one beam,
and these mirrors for another beam. And when they have finished the trip,
you recombine them here and bring them back out here.
I will show you better with a laser beam. And, better still, with some smoke.
Now, since the straight ahead beam will be slowed down more than the sideways beam,
the two beams will recombine here out of phase. With the straight ahead beam lagging behind, right?
All mixing light beams make interference patterns. So that's what you get to start with, here.
I will show you, on this card, see?
Michelson and Morley reckoned that if the ether existed,
this pattern should be altered when you change the angle the beams were being shot through it.
So, to do that, they rotated the entire experiment
and took 16 readings on no less than 36 rotations.
Just to be sure they were seeing what they were seeing.
Which was:
no change in the interference fringe, at all.
And you know what that meant? No shift, no ether. No ether, no anything!
The Viennese genius who turned everything upside down was called Ernst Mach.
Mach turned everything upside down because that's what he spent his time doing,
turning people upside down, or sideways, or round and round.
By 1895, Mach had spent years investigating what happened to peoples’ senses
when they were put into every position he could conceive of. He would blindfold them, for instance,
and then tilt them in an environment that was also moving, and test their sense of direction.
Mach came up with some of the basic ideas of modern perceptual science.
He was really trying to find out how much of what you observed was affected by your senses.
The way, for example, you could be in something that was moving up or down, and yet feel as if you weren't.
Mach became convinced that much of what you sensed about the world was in your mind,
and that everything you could ever say about reality was subjective,
altered by conditions like temperature or sound, acceleration, pressure, even mood.
There was nothing out there that you could be certain of, unless you were in direct contact with it.
Were you going down here? Or was Vienna going up?
But it was how Mach used his work on perception,
that made him such a big wheel among the scientific thinkers of the time.
Because, he argued, that it showed all a scientist could be sure of,
was what his own personal experiences, five senses, showed him.
Take movement for instance, forces on you acting up or down or from side to side.
You might invent some scientific law to explain those forces,
but you should also remember that it was you that invented the law.
For Mach, there was no reason why the rest of the cosmos should be doing what your little bit was doing.
So, science should only describe, not try to explain.
And, even description is relative, I mean, am I moving, or is the background moving?
Or take the position of a star. It depends on where you see it from,
which depends on the date and time, which depends on the position of the Earth in solar orbit,
in a solar system moving round and round at the edge of the galaxy.
Which, itself, might be drifting away from some other galaxy and so on and so on.
So, say you have decided that I am moving and the background is standing still.
How do you know that the background isn't moving relative to something else? Hmm?
That's why there was no point in playing around with light beams to try and find some
theoretical universal absolute.
There were no absolutes you could ever know anything about. “They couldn't find the ether,” said Mach,
“because there was no ether to find”. Well, you can guess what that did to Newton.
Quite. And there was worse to come, from people working on these things.
Well, these things. Cathode ray tubes.
Another mystery force, cathode rays. Anything they hit, glowed.
And you could make the glow move with a magnet. Electricity was affected by magnetism.
So, were the cathode rays electric?
Well, if you took some cathode rays and used a magnet to aim them at two little gold foil leaves,
the leaves separated, which they only did if they were getting electrified.
A positively charged rod would cancel that effect, so that meant that the cathode rays were making negative electricity.
In 1897, an Englishman called Thompson, who thought cathode rays were really particles,
worked out a technique for weighing them.
He changed the direction of the stream of particles with a magnetic field,
and then saw how much of an electrical field was needed to straighten it out again.
Sure enough, they turned out to be particles of negative electricity, we call them ‘electrons’,
that were 1000 times smaller than the smallest atom.
Thompson reckoned he had the basic unit of electricity, there in his measuring tube.
But the big shock was this:
ultra violet light waves would knock negative electrons out of metal.
Look: the gold leaves collapse.
By the turn of the century,
what with waves of the mysterious force rippling out through ether nobody could find,
and incredible shrinking Irish instruments and Mach saying it was all meaningless anyway,
and Thompson's light rays knocking subatomic particles account of metal, well,
poor old Newton's universe had more holes in it than this bit of Gruyere.
And the physicists were, to put it mildly, cheesed-off with the whole affair.
Until, fittingly, a Swiss government bureaucrat, called Einstein, simply invented a new universe.
And the reason I am telling you this onboard a Concorde flight is because Concorde goes at over Mach two.
That's the Mach you know and who gave Einstein the idea.
Two stands for twice the speed of sound, which Mach identified.
Which means that I'm going at quite a lick, which makes my point for me.
Because, Einstein's cosmic rewrite of the laws of nature just said that everything in the universe was relative.
And everything you observed about it, depended on the frame of reference you were in at the time.
Like this Concorde cabin where I am standing still, dropping my pen in comfort.
In this cabin. I am not going at 1400 miles an hour, am I?
And everything works like that, conditioned by its frame of reference.
All the electrics in all the instruments on board this plane
obey the same laws they would if they were standing still. Because, inside this frame, like me,
they are not going at Mach two. And all the laws of nature behave in the same way.
This beam of light is going out in all directions at 186,000 miles second
and being on Concorde makes no difference to its speed forwards, backwards, or sideways.
That's why the way the Earth was moving made no difference to the Michelson and Morley light beams.
It never could have, you could never measure the speed of light except relative to your frame of reference.
And like Mach said, you can never measure it against anything outside your frame of reference
because you would never know what it was doing, relative to you.
There was no absolute, because you could never know anything was absolute.
So, that sorted out the light beam and the ether business.
As for Thompson's light knocking electrons out of metal, well Einstein said, “obviously, light came in bits,
and knocked bits out of the metal. And the more intense the light, the more bits it knocked out.
However, this moving moment in the study of light went almost entirely unnoticed
in the light of another moving moment in the study of light.
The movies. Another great example of the triumph of technology.
It was probably the movies, above all, that convinced the millions that, in this new 20th-century,
fortune and success would come only to the kind of fellow who kept up with science.
The modern hero would be the man who could change with the times.
Taking advantage of the latest technology was going to be the way to get ahead.
The movies showed that, without science, life was no fun at all.
The music, of course, wasn't really there. It still had to be played by somebody in the movie theatre,
watching the film.
Until somebody used the light going through the film to hit metal, to produce electrons, to make electricity
for a loudspeaker.
And the public's love of technology really took off. With the talkies.
Georgie Porgy is a guy who is very bashful and so shy.
The ladies prize him, they idolize him.
Let's not knock it. I would be out of work without it.
But, it did all ignore the awful implications of what Einstein had said.
If the more intense the light was, the more electrons is knocked out of the wall,
that sounded as if light wasn't a wave at all, more like a stream of particles.
Einstein said “sure,” and called them photons.
That's how something like this works. When I remove the card, the stream of light particles can hit a metal target.
That gives off electrons, that makes electricity, and that closes the door.
Well, if light wasn't a wave, that blew the last 100 years’ work right away, didn't it?
But then, what about Young? And the way light interfered with itself
to produce those light and dark ripples the way only waves can, what about that?
In 1923, the same year as that movie you saw.
A French man called de Brolie muddied the waters by coming at it the other way round.
If waves could be particles, could particles be waves? Because if they could,
they would make patterns like waves, wouldn’t they?
Now this was getting out of hand. A wave is a wave, and a particle is a particle.
Right? Wrong. And in 1927, an accident proved it.
Two Americans called Davison and Germer, were quietly shooting electrons from an electron gun
at a nickel target to see how the electrons bounced off,
when the vacuum tube in which their whole gizmo worked, cracked. Disaster.
The air coming in had contaminated the target. Having heated it up, and so on, to clean it,
back to work. Only this time, when they moved their little electron collector around the target to catch the electrons,
no electrons. Then lots. Then none. Then lots. And so on.
Big investigation: turned out, the reheat on the target had produced big crystals on its surface.
Now, in crystals, atoms are neatly spaced like that.
So now the electrons were coming in and bouncing off, but in a series, like that.
Now, just supposing those electrons were waves, they would do this, would they?
And those waves would interact like waves do, building up or cancelling out,
so you would get lots, none, lots, none, lots, none. Interference ripples. Don't believe me?
Modern equipment, vacuum tube inside electron gun and target, the electrons scatter out here.
I will fire the gun.
See? Interference ripples. Particles are waves.
Now, if you are getting a bit worried about how things could be two things at once,
hold on to your subatomic hat, because the bottom is about to drop out of everything.
I will go slow because I won't understand it if I don't.
In 1927, a fellow called Heisenberg decided to take a look at what these particle electrons,
and the waves they seemed to go with, were up to.
And he announced that you could either say where an electron was,
by examining an individual intense wave crest (the electron would be in there somewhere)
or how fast it was going, by looking at a whole group of waves moving, getting the general speed,
but then you wouldn't know which wave crest had the electron.
So, position or speed, but not both.
And worse, to look, you had to shine a light to see, no?
And the light particles would hit the electrons.
So you could never be sure that the electrons were where they were, doing what they were doing,
naturally or because you had hit them, get it?
Heisenberg called this drain down which everything went, ‘The Uncertainty Principle’.
“Now we know,” he said, “that we shall never know”.
He said that because you can't know if it's a particle or a wave.
There is nothing at the fundamental level of existence that you can see as it is,
because in seeing it, you do something to it.
There is no true basic reality to find. Beyond the one you, yourself, make
by looking, if there is any reality at all. And, in that case, which way is up, for God’s sake?
Here at the high energy physics laboratory outside Geneva,
for scientists, the truth is you can only talk about the universe in terms of probabilities,
you can never, by definition, be certain about it.
You see what that implies? The comfortable certainty science is supposed to provide,
isn't there anymore. But we ignore that fact, we only see the technology.
The electron that caused all the trouble, makes a digital watch work
and all that electronics, and that is good enough.
As far as we are concerned, the world is still the same as it was at the beginning of this programme.
Newton's world. When there was a true reality, final certainty, order, with everything knowable,
a Swiss clockwork type world. But as you have seen, in science, that world is long gone.
We talk about living with uncertainty but it is this kind of uncertainty. War, crime, disaster famine:
uncertainty about how tomorrow will turn out.
But, in some form or other, it will turn out.
So, is there any direction to our journey into knowledge?
Or do we make up the route as we go along? And if that is the case, what is knowledge?
The next, and final, programme will see where that question leads.