Delphi Complete Works of Stephen Leacock, page 403
By about 1880 it seemed as if the world of science was fairly well explained. Metaphysics still talked in its sleep. Theology still preached sermons. It took issue with much of the new science, especially with geology and the new evolutionary science of life that went with the new physical world. But science paid little attention.
For the whole thing was so amazingly simple. There you had your space and time, two things too obvious to explain. Here you had your matter, made up of solid little atoms, infinitely small but really just like birdseed. All this was set going by and with the Law of Gravitation. Once started, the nebulous world condensed into suns, the suns threw off planets, the planets cooled, life resulted and presently became conscious, conscious life got higher up and higher up till you had apes, then Bishop Wilberforce, and then Professor Huxley.
A few little mysteries remained, such as the question of what space and matter and time and life and consciousness really were. But all this was conveniently called by Herbert Spencer the Unknowable, and then locked in a cupboard and left there.
Everything was thus reduced to a sort of Dead Certainty. Just one awkward skeleton remained in the cupboard. And that was the peculiar, mysterious aspect of electricity, which was not exactly a thing and yet was more than an idea. There was also, and electricity only helped to make it worse, the old puzzle about “action at a distance.” How does gravitation pull all the way from here to the sun? And if there is nothing in space, how does light get across from the sun in eight minutes, and even all the way from Sirius in eight years?
Even the invention of “ether” as a sort of universal jelly that could have ripples shaken across it proved a little unconvincing.
Then, just at the turn of the century, the whole structure began to crumble.
The first note of warning that something was going wrong came with the discovery of X-rays. Sir William Crookes, accidentally leaving around tubes of rarefied gas, stumbled on “radiant matter,” or “matter in the fourth state,” as accidentally as Columbus discovered America. The British Government knighted him at once (1897), but it was too late. The thing had started. Then came Guglielmo Marconi with the revelation of more waves, and universal at that. Light, the world had learned to accept, because we can see it, but this was fun in the dark.
There followed the researches of the radioactivity school and, above all, those of Ernest Rutherford which revolutionized the theory of matter. I knew Rutherford well as we were colleagues at McGill for seven years. I am quite sure that he had no original intention of upsetting the foundations of the universe. Yet that is what he did, and he was in due course very properly raised to the peerage for it.
When Rutherford was done with the atom, all the solidity was pretty well knocked out of it.
Till these researches began, people commonly thought of atoms as something like birdseed — little round, solid particles, ever so little, billions to an inch. They were small. But they were there. You could weigh them. You could apply to them all the laws of Isaac Newton about weight and velocity and mass and gravitation — in other words, the whole of first-year physics.
Let us try to show what Rutherford did to the atom. Imagine to yourself an Irishman whirling a shillelagh around his head with the rapidity and dexterity known only in Tipperary or Donegal. If you come anywhere near, you’ll get hit with the shillelagh. Now make it go faster; faster still; get it going so fast that you can’t tell which is Irishman and which is shillelagh. The whole combination has turned into a green blur. If you shoot a bullet at it, it will probably go through, as there is mostly nothing there. Yet if you go up against it, it won’t hit you now, because the shillelagh is going so fast that you will seem to come against a solid surface. Now make the Irishman smaller and the shillelagh longer. In fact, you don’t need the Irishman at all; just his force, his Irish determination, so to speak. Just keep that, the disturbance. And you don’t need the shillelagh either, just the field of force that it sweeps. There! Now put in two Irishmen and two shillelaghs and reduce them in the same way to one solid body — at least it seems solid but you can shoot bullets through it anywhere now. What you have now is a hydrogen atom — one proton and one electron flying around as a disturbance in space. Put in more Irishmen and more shillelaghs — or, rather, more protons and electrons — and you get other kinds of atoms. Put in a whole lot — eleven protons, eleven electrons; that is a sodium atom. Bunch the atoms together into combinations called molecules, themselves flying round — and there you are! That’s solid matter, and nothing in it at all except disturbance. You’re standing on it right now: the molecules are beating against your feet. But there is nothing there, and nothing in your feet. This may help you to understand how “waves,” ripples of disturbance — for instance, the disturbance you call radio — go right through all matter, indeed right through you, as if you weren’t there. You see, you aren’t.
The peculiar thing about this atomic theory was that whatever the atoms were, birdseed or disturbance, it made no difference in the way they acted. They followed all the laws of mechanics and motion, or they seemed to. There was no need to change any idea of space or time because of them. Matter was their forte, like wax figures with Artemus Ward.
One must not confuse Rutherford’s work on atoms with Einstein’s theories of space and time. Rutherford worked all his life without reference to Einstein. Even in his later days at the Cavendish Laboratory at Cambridge when he began, ungratefully, to smash up the atom that had made him, he needed nothing from Einstein. I once asked Rutherford — it was at the height of the popular interest in Einstein in 1923 — what he thought of Einstein’s relativity. “Oh, that stuff!” he said. “We never bother with that in our work!” His admirable biographer, Professor A. S. Eve, tells us that when the German physicist, Wien, told Rutherford that no Anglo-Saxon could understand relativity, Rutherford answered, “No, they have too much sense.”
But it was Einstein who made the real trouble. He announced in 1905 that there was no such thing as absolute rest. After that there never was. But it was not till just after the Great War that the reading public caught on to Einstein and that little books on “Relativity” covered the bookstalls.
Einstein knocked out space and time, as Rutherford knocked out matter. The general viewpoint of relativity toward space is very simple. Einstein explains that there is no such place as here. “But,” you answer, “I’m here; here is where I am right now.” But you’re moving, you’re spinning around as the earth spins; and you and the earth are both spinning around the sun, and the sun is rushing through space toward a distant galaxy, and the galaxy itself is beating it away at 26,000 miles a second. Now, where is that spot that is here! How did you mark it? You remember the story of the two idiots who were out fishing, and one said, “We should have marked that place where we got all the fish,” and the other said, “I did; I marked it on the boat.” Well, that’s it. That’s here.
You can see it better still if you imagine the universe swept absolutely empty: nothing in it, not even you. Now put a point in it, just one point. Where is it? Why, obviously it’s nowhere. If you say it’s right there, where do you mean by there? In which direction is there? In that direction? Oh! Hold on, you’re sticking yourself in to make a direction. It’s in no direction; there aren’t any directions. Now put in another point. Which is which? You can’t tell. They both are. One is on the right, you say, and one on the left. You keep out of that space! There’s no right and no left. Join the points with a line. Now you think you’ve got something, and I admit this is the nearest you have come to it. But is the line long or short? How long is it? Length soon vanishes into a purely relative term. One thing is longer than another: that’s all.
There’s no harm in all this, so far. To many people it’s as obvious as it is harmless. But that’s only the beginning. Leave space alone for a moment and take on time and then things begin to thicken. If there is no such place as here, a similar line of thought will show that there’s no such time as now — not absolutely now. Empty the universe again as you did before, with not a speck in it, and now ask, What time is it? God bless me, how peculiar! It isn’t any time. It can’t be; there’s nothing to tell the time by. You say you can feel it go; oh, but you’re not there. There will be no time until you put something into space with dimensions to it — and then there’ll be time, but only as connected somehow — no knowing how — with things in space. But just as there is no such thing as absolute top or bottom in space, so there is a similar difficulty as to time backward and time forward.
The relativity theory undertakes to explain both space and time by putting them together, since they are meaningless without one another, into a compound called “space-time continuum.” Time thus becomes, they say, the fourth dimension of space. Until just recently it was claimed further that to fit these relationships together, to harmonize space and time, space must have a curve, or curvature. This was put over to the common mind by comparing what happens in space with what happens to a fly walking on a sphere (a globe). The fly walks and walks and never gets to the end. It’s curved. The joke is on the fly. So was the joke long ago on the mediaeval people who thought the world was flat. “What happened to the theory of the earth,” writes Eddington, “has happened also to the world of space and time.”
The idea was made plainer for us by comparing space-time to an onion skin, or rather to an infinite number of onion skins. If you have enough, you can fill all space. The universe is your onion, as it was Shakespeare’s oyster.
The discovery by Einstein of this curvature of space was greeted by the physicists with the burst of applause that greets a winning home run at baseball. That brilliant writer just mentioned, Sir Arthur Eddington, who can handle space and time with the imagery of a poet, and even infiltrate humour into gravitation — as when he says that a man in an elevator falling twenty stories has an ideal opportunity to study gravitation — is loud in his acclaim. Without this curve, it appears, things won’t fit into their place. The fly on the globe, as long as he thinks it flat (like Mercator’s map), finds things shifted, as by some unaccountable demon, to all sorts of wrong distances. Once he gets the idea of a sphere, everything comes straight. So with our space. The mystery of gravitation puzzles us, except those who have the luck to fall in an elevator, and even for them knowledge comes too late. They weren’t falling at all: just curving. “Admit a curvature of the world,” wrote Eddington in his Gifford Lectures of 1927, “and the mysterious agency disappears. Einstein has exorcised this demon.”
But it appears now, fourteen years later, that Einstein doesn’t care if space is curved or not. He can take it either way. A prominent physicist of today, head of the department in one of the greatest universities of the world, wrote me on this point: “Einstein had stronger hopes that a general theory which involved the assumption of a property of space, akin to what is ordinarily called curvature, would be more useful than he now believes to be the case.” Plain talk for a professor. Most people just say Einstein has given up curved space. It’s as if Sir Isaac Newton years after had said, with a yawn, “Oh, about that apple — perhaps it wasn’t falling.”
Now with the curve knocked out of it, the space-time continuum, with these so-called four dimensions, becomes really a very simple matter; in fact, only a very pretentious name for a very obvious fact. It just means that information about an occurrence is not complete unless we know both where it happened and when it happened. It is no use telling me that Diogenes is dead if I didn’t know that he was alive. Obviously “time-when” or “place-where” are bound together and coexist with one another. If there were no space — just emptiness — there could be no time. It wouldn’t count itself. And if there were no time, there could be no space. Start it and it would flicker out again in no time — like an electric bulb on a wobble-plug. Space-time continuum is just a pretentious name for this consequence of consciousness. We can’t get behind it. We begin life with it, as the chicken out of the egg begins with its cell memory. All the mathematics based on “space-time continuum” get no further, as far as concerns the search for reality. It gets no further than the child’s arithmetic book that says, “If John walks two miles every day for ten days,” etc., etc. The child hooks space and time with a continuum as easily as the chicken picks up gravel.
III
But, unhappily, we can’t get away from the new physics quite as simply as that. Even if we beat them out on space and time, there is far worse to come. That’s only the start of it, for now, as the fat boy in Pickwick said, “I’m going to make your flesh creep.” The next thing to go is cause and effect. You may think that one thing causes another. It appears that it doesn’t. And, of course, when cause and effect go, the bottom is out of the universe, since you can’t tell, literally can’t, what’s going to happen next. This is the consequence of the famous Quantum Theory, first hinted at by Professor Max Planck about forty years ago and since then scrambled for by the physicists like dogs after a bone. It changes so fast that when Sir Arthur Eddington gave the Gifford Lectures referred to, he said to his students that it might not be the same when they met next autumn.
But we cannot understand the full impact of the Quantum Theory in shattering the world we lived in, without turning back again to discuss time in a new relation, namely, the forward-and-backwardness of it, and to connect it up again with the Second Law of Thermodynamics — the law, it will be recalled, that condemns us to die of cold. Only we will now call it by its true name — which we had avoided before — as the Law of Entropy. All physicists sooner or later say, “Let us call it Entropy,” just as a man says when you get to know him, “Call me Charlie.”
So we make a new start.
I recall, as some other people still may, a thrilling melodrama called The Silver King. In this the hero, who thinks he has committed a murder (of course, he hasn’t really), falls on his knees and cries, “Oh, God, turn back the universe and give me yesterday.” The supposed reaction of the audience was, “Alas, you can’t turn back the universe!”
But nowadays it would be very different. At the call, the Spirit of Time would appear — not Father Time, who is all wrong, being made old — but a young, radiant spirit in a silver frock made the same back and front. “Look,” says the Spirit, “I’m going to turn back the universe. You see this wheel turning around? Presto! It’s going the other way. You see this elastic ball falling to the floor? Presto! It’s bouncing back. You see out of the window that star moving west? Presto! It’s going east. Hence accordingly,” continues the Spirit, now speaking like a professor, so that the Silver King looks up in apprehension, “time, as evidenced by any primary motion, is entirely reversible so that we cannot distinguish between future time and past time: indeed, if they move in a circle both are one.”
The Silver King leaps up, shouts, “Innocent! Innocent!” and dashes off, thus anticipating Act V and spoiling the whole play. The musing Spirit, musing of course backwards, says, “Poor fellow, I hadn’t the heart to tell him that this only applies to primary motion and not to Entropy. And murder, of course, is a plain case of Entropy.”
And now let us try to explain. Entropy means the introduction into things that happen of a random element, as opposed to things that happen and “unhappen,” like a turning wheel, good either way, or a ball falling and bouncing as high as it falls, or the earth going around the sun. These primary motions are “reversible.” As far as they are concerned, time could just as well go backwards as forward. But now introduce the element of random chance. You remember how Humpty Dumpty fell off the wall? All the king’s horses and all the king’s men couldn’t put Humpty together again. Of course not. It was a straight case of Entropy. But now consider a pack of cards fresh from the maker. Are they all in suits, all in order again? They might so arrange themselves, but they won’t. Entropy. Take this case. You show a motion picture of a wheel spinning. You run it backwards; it spins the other way. That’s time, the time of primary motion, both ways alike. Now show a motion picture of a waiter with a tray of teacups. He drops them; they roll in a hundred fragments. Now run it backwards; you see all the little fragments leap up in the air, join neatly into cups, and rest on the tray. Don’t think that the waiter smiles with relief. He doesn’t: He can’t smile backwards: He just relaxes from horror to calm.
Here then is Entropy, the smashing down of our world by random forces that don’t reverse. The heat and cold of Carnot’s Second Law are just one case of it. This is the only way by which we can distinguish which of two events came first. It’s our only clue as to which way time is going. If procrastination is the thief of time, Entropy is the detective.
The Quantum Theory begins with the idea that the quantities of disturbance in the atom, of which we spoke, are done up, at least they act that way, in little fixed quantities (each a Quantum — no more, no less), as if sugar only existed by the pound. The smallness of the Quantum is beyond comprehension. A Quantum is also peculiar. A Quantum in an atom flies around in an orbit. This orbit may be a smaller ring or a bigger ring. But when the Quantum shifts from orbit to orbit, it does not pass or drift or move from one to the other. No, sir. First, it’s here and then it’s there. Believe it or not, it has just shifted. Its change of place is random, and not because of anything. Now the things that we think of as matter and movements and events (things happening) are all based, infinitely far down, on this random dance of Quantums. Hence, since you can’t ever tell what a Quantum will do, you can’t ever say what will happen next. Cause and effect are all gone.
But as usual in this bright, new world of the new physics, the statement is no sooner made than it is taken back again. There are such a lot of Quantums that we can feel sure that one at least will turn up in the right place — by chance, not by cause.
The only difficulty about the Quantum Theory has been that to make the atomic “orbits” operate properly, and to put the Quantum into two places at once, it is necessary to have “more dimensions” in space. If they are not in one, they are in another. You ask next door. What this means I have no idea.
