Part 9

Whereas the fission process for the release of nuclear energy entails making little ones out of big ones, the fusion process involves making big ones out of little ones. In both processes the products weigh less than the original materials, the loss of mass coming out in the form of energy. According to the generally accepted hypothesis, the fusion process is the one operating in the sun and the stars of the same family. The radiant energy given off by them, it is believed, is the result of the fusion of four hydrogen atoms into one atom of helium, two of the protons losing their positive charge, thus becoming neutrons. Since a helium atom weighs nearly eight tenths of one per cent less than the total weight of the four hydrogen atoms, the loss of mass is thus nearly eight times that produced by fission, with a corresponding eightfold increase in the amount of energy liberated. This process, using light hydrogen, is not feasible on earth.

The nuclei of all atoms are thus vast storage depots of cosmic energy. We must think of them as cosmic safe-deposit vaults, in which the Creator of the universe, if you will, deposited at the time of creation most of the energy in the universe for safekeeping. The sun and the other giant stars that give light have, as it were, drawing accounts in this “First National Bank and Trust Company of the Universe,” whereas we on this little planet of ours in the cosmic hinterland are much too poor to have such a bank account. So we have been forced all these years we have been on earth to subsist on small handouts from our close neighbor the sun, which squanders millions all over space, but can spare us only nickels, dimes, and quarters (depending on the seasons of the year) for a cup of coffee and a sandwich. We are thus in the true sense of the word cosmic beggars, living off the bounty of a distant relative.

The discovery of fission in 1939 meant that after a million years of exclusive dependence on the sun we had suddenly managed to open a modest drawing account of our own in this bank of the cosmos. We were enabled to do it by stumbling upon two special master keys to five of the cosmic vaults. One of these keys we call fission; the other, which allows us entry into a much richer chamber of the vault, we call fusion. We can get a lot of the stored-up cosmic treasure by using the key to the fission vaults alone, but, as with our terrestrial bank vaults, which generally require two keys before they can be opened, it is not possible to use the key to the fusion vault unless we first use the fission key.

Except for the payment of our heat and light bill, the sun gives us nothing directly in cash. Instead it deposits a very small pittance in the plants, which serve as its major terrestrial banks. The animals then rob the plants and we rob them both. When we eat the food we live by we thus actually eat sunshine.

The sun makes its deposits in the plant through an agent named chlorophyll, the stuff that makes the grass green. Chlorophyll has the uncanny ability to catch sunbeams and to hand them over to the plant. A chemical supergenius inside the plant changes the sunlight energy into chemical energy, just as a bank teller changes bills into silver. With this chemical energy at their disposal, a great number of devilishly clever chemists in the plants’ chemical factory go to work building up many substances to serve as vaults in which to store up a large part of the energy, using only part of it for their own subsistence.

The building materials used by these chemists inside the plants consist mainly of carbon-dioxide gas from the atmosphere, and water from the soil, plus small amounts of minerals either supplied by the good earth or by fertilizers. Carbon dioxide, by the way, composed of one atom of carbon and two atoms of oxygen, is the stuff you exhale. In solid form it is what we know as dry ice, used in efforts to make rain. It is present in the atmosphere in large amounts.

Out of the carbon dioxide and water the chemists in the plants build cellulose, starch, sugar, fat, proteins, vitamins, and scores of other substances, all of which serve as vaults for the sun’s rays caught by the chlorophyll. The biggest vaults of all, storing most of the energy, are the cellulose, sugars and starches, fats and proteins. There the stored energy remains until it is released by processes we call burning or digestion, both of which, as we shall see, are different terms for the same chemical reaction. When we burn wood, or the petrified ancient wood we know as coal, we burn largely the cellulose, the chief component of the solid part of plants. When we eat the plants, or the animals in whom the plant tissues are transformed into flesh by the solar energy stored within them, it is the sugars, starches, fats, and proteins that give us the energy we live by.

In the process of burning wood or coal the large cellulose vaults, composed of carbon, hydrogen, and oxygen, are broken up, thus allowing the original solar energy, stored up within them as chemical energy, to escape in the form of heat and light. This is the same heat and light deposited there by the sun many years before—in the case of coal, some two hundred million years back. The process of burning thus transforms the chemical energy in the plants back to its original form of light and radiant heat energy. The complex carbon and hydrogen units in the cellulose are broken up, each freed carbon atom uniting within two oxygen atoms in the air to form carbon dioxide again, while two hydrogen atoms unite with one of oxygen to form water. Thus we see that the cellulose vaults are broken up once more into the original building bricks out of which the chemists in the plants had fashioned them.

When we eat plant or animal food to get the energy to live by, exactly the same process takes place except at a lower temperature. The sunlight deposit vaults of sugar, starch, and fat, also composed, like cellulose, of carbon, hydrogen, and oxygen, are broken up by the digestive system into their component parts, thus allowing the original solar energy stored within them to get free in the form of chemical energy, which our body uses in its essential processes. Here, too, the end products are carbon dioxide, which we exhale, and water. About half the energy we thus obtain is used by us for the work we do. The other half is used by the body for building up the tissues burned up as part of the regular wear and tear of life.

We thus burn food for our internal energy as we burn cellulose for our external energy. The interesting thing here is that, in both types of burning, fission as well as fusion processes take place. The fission is the splitting of the cellulose, sugar, fats, starches, and proteins into carbon and hydrogen atoms. The fusion part is the union of the carbon and the hydrogen with oxygen to form carbon dioxide and water. The fusion part is just as necessary to release the stored-up solar energy in the wood or coal as is the fission part, for, as everyone knows, unless there is oxygen for the carbon to fuse with, no combustion (burning) can take place and hence no release of energy. The plant vaults would remain closed absolutely tight.

At this point two things become clear. We see, in the first place, that whenever we get any kind of energy in any form we do not in any way create any of it. All we do is merely draw on something that is already stored up; in the case of coal and wood by the sun, in the case of uranium and hydrogen by the same power that created the sun and all energy. We draw water from the spring, but we do not make the water. On the other hand, we cannot draw the water unless we first find the spring, and even then we cannot draw it unless we have a pitcher.

And we also see, in the second place, that fission and fusion are common everyday phenomena that occur any time you burn anything. Both are essential whenever energy is released, whether it is the chemical energy from coal or the atomic energy from the nuclei of uranium, deuterium, or tritium. When you light a cigarette you employ both fission and fusion or you don’t smoke. The first fission and fusion take place in the lighting of the match, the cellulose in the match (whether it is wood or paper) being fissioned (that is, split into its component atoms of carbon and hydrogen). These atoms are then fusioned with the oxygen in the air. The same thing happens when the tobacco catches fire. In each case the fusion with the oxygen makes possible the fission of the cellulose. When we burn U-235, or plutonium, we again get both fission and fusion, except that, instead of oxygen, the nuclei of these elements first fuse with a neutron before they are split apart. Thus we see that the process of burning U-235, or plutonium, requires not only fission but fusion as well, without which they could not burn. This is true also in hydrogen fusion. When you burn deuterium by fusing two deuterons (nuclei of deuterium) to form helium of atomic weight three, plus a neutron, one of the two deuterons is split in half in the process. Similarly, when you burn tritium by fusion two tritons (nuclei of tritium), one of the tritons splits into two neutrons and a proton, the one proton joining the other triton to form helium of atomic weight four.

Thus we see that fission and fusion are the cosmic firebrands that are always present whenever a fire is lighted, chemical or atomic, whether the fuel is wood, coal, or oil, or uranium, plutonium, deuterium, or tritium. Both, with some variations, are essential for opening the cosmic safe where the energy of the universe is kept in storage. The only reason you get much more energy in the fission and fusion of atomic nuclei is that so much more had been stored in them than in the cellulose vaults on this planet.

The same reason that limits our ability to obtain stored chemical energy to a few fuels also limits our ability to obtain atomic energy. Coal, oil, and wood are the only dividend-paying chemical-energy stocks. Similarly only five elements, uranium 233 and 235, plutonium, deuterium, and tritium are the only dividend-paying atomic-energy stocks, and of these only two (U-235 and deuterium) exist in nature. The other three are re-created from other elements by modern alchemical legerdemain. What is more, we know for a certainty that it will never be possible to obtain atomic energy from any other element, by either fission or fusion.

This should put to rest once and for all the notion of many, including some self-styled scientists, that the explosion of a hydrogen bomb would set the hydrogen in the waters, and the oxygen and the nitrogen in the air, on fire and thus blow up the earth. The energy in common hydrogen is locked up in one of those cosmic vaults which only the sun and the stars that shine can open and which no number of H-bombs could blow apart. Oxygen and nitrogen are locked even for the sun. As for the deuterium in the water, it cannot catch fire unless it is highly concentrated, condensed to its liquid form, and heated to a temperature of several hundred million degrees. Hence all this talk about blowing up the earth is pure moonshine.

But while we know that we have reached the limit of what can be achieved either by fission or by fusion, that by no means justifies the conclusion that we have reached the ultimate in discovery and that fission and fusion are the only possible methods for tapping the energy locked up in matter. We must remember that fifty years ago we did not even suspect that nuclear energy existed and that until 1939 no one, including Dr. Einstein, believed that it would ever become possible to use it on a practical scale. We simply stumbled upon the phenomenon of fission, which in its turn opened the way to fusion.

If science tells us anything at all, it tells us that nature is infinite and that the human mind, driven by insatiable curiosity and probing ever deeper into nature’s mysteries, will inevitably find ever greater treasures, treasures that are at present beyond the utmost stretches of the imagination—as far beyond fission and fusion as these are beyond man’s first discovery of how to make a fire by striking a spark with a laboriously made flint. The day may yet come, and past history makes it practically certain that it will come, when man will look upon the discovery of fission and fusion as we look today upon the crudest tools made by primitive man.

A great measure of man’s progress has been the result of serendipity, the faculty of making discoveries, by chance or sagacity, of things not sought for. Many an adventure has led man to stumble upon something much better than he originally set out to find. Like Columbus, many an explorer into the realms of the unknown has set his sights on a shorter route to the spices of India only to stumble upon a new continent. Unlike Columbus, however, the explorers in the field of science, instead of being confined to this tiny little earth of ours, have the whole infinite universe as the domain of their adventures, and many a virgin continent, richer by far than any yet discovered, still awaits its Columbus.

Roentgen and Becquerel were exploring what they thought was an untrodden path in the forest and came upon a new road that led their successors to the very citadel of the material universe. Young Enrico Fermi was curious to find out what would happen if he fired a neutron into the nucleus of uranium, hoping only to create a heavier isotope of uranium, or at best a new element. His rather modest goal led five years later to the fission of uranium, and in another six years to the atomic bomb.

Yet, as we have seen, in both fission and fusion only a very small fraction of the mass of the protons and neutrons in the nuclei of the elements used is liberated in the form of energy, while 99.3 to 99.9 per cent of their substance remains in the form of matter. We know of no process in nature which converts 100 per cent of the matter in protons and neutrons into energy, but scientists are already talking about finding means for bringing about such a conversion. They are seeking clues for such a process in the mysterious cosmic rays that bombard the earth from outer space with energies billions of times greater than those released by fission or fusion, great enough to smash atoms of oxygen or nitrogen, or whatever other atoms they happen to hit in the upper atmosphere, into their component protons and neutrons. Luckily, their number is small and most of their energy is spent long before they reach sea level.

But we have already learned how to create secondary cosmic-ray particles of relatively low energies (350,000,000 electron-volts) with our giant cyclotrons. The creation of these particles, known as mesons, which are believed to be the cosmic cement responsible for the nuclear forces, represents the actual conversion of energy into matter. This is the exact reverse of the process taking place in fission and fusion, in which, as we have seen, matter is converted into energy. And we are now about to complete multibillion-volt atom-smashers that will hurl atomic bullets of energies of from three to ten billion volts at the nuclei of atoms. With these gigantic machines, known as the cosmotron (at the Brookhaven National Laboratory of the Atomic Energy Commission) and the bevatron (at the University of California), we shall be able to smash nuclei into their individual component protons and neutrons and thus get a much more intimate glimpse of the forces that hold the nuclei together. What is more, instead of creating only mesons, particles with only 300 electron masses, we shall be able for the first time to convert energy into protons and neutrons, duplicating, as far as is known, an act of creation that has not taken place since the beginning of the universe. Man at last will be creating the very building blocks out of which the universe is made, as well as the cosmic cement that holds them together.

What new continents will our first glimpse into the mechanism of the very act of creation of matter out of energy reveal? What new secrets will be uncovered before the dazzled eyes and mind of man when he takes the nucleus of the atom completely apart at last? Not even Einstein could tell us. But, as Omar Khayyám divined, “a single Alif” may provide “the clue” that, could we but find it, leads “to the Treasure-House, and peradventure to the Master too.” The fact is that we already have opened the door to the anteroom of the treasure-house, and we are about to unlock the door to one of its inner chambers. What shall we find there? No one as yet knows. But we do know that every door man has opened so far has led to riches beyond his wildest dreams, each new door bringing greater rewards than the one before. On the other hand, we also know that the treasure-house has many mansions, and that no matter how many chambers he may enter, he will always find new doors to unlock. For we have learned that the solution of any one secret always opens up a thousand new mysteries.

We also have learned, to our sorrow, that any new insight gained into nature’s laws and forces can be used for great good and for equally great evil. The greater the insight, the greater the potentialities for good or evil. The new knowledge he is about to gain by his deeper insight into the heart of matter, and by his ability to create it out of energy, may offer man the means to make himself complete master of the world he lives in. It is equally true, alas, that he could use it to destroy that world even more thoroughly than with the hydrogen bomb.

As already stated, scientists are even now discussing the possibility of finding means for the complete annihilation of matter by the conversion of the entire mass of protons and neutrons into energy, instead of only 0.1 to 0.7 per cent. And while the total annihilation of protons and neutrons still seems highly speculative, we already know that such a process actually does take place in the realm of the electron. This is the phenomenon already achieved numerous times on a small scale in the laboratory, in which a positive electron (positron) and an electron with a negative charge completely destroy each other, their entire mass being converted into energy. Luckily, this is at present only a laboratory experiment, in which each positron must be individually produced, since there are hardly any positive electrons in our part of the universe. But suppose the new knowledge we are about to pry loose from the inner citadel of matter reveals to us a new process, at present not even suspected, that would release positrons in large numbers, just as the fission and fusion processes made possible for the first time the liberation of large quantities of neutrons. Such an eventuality, by no means beyond the realm of the possible, would open potentialities of horror alongside which those of the H-bomb, even the rigged one, would be puny. For any process that would release large numbers of positrons in the atmosphere, in a chain reaction similar to the one now liberating neutrons, may envelop the earth in one deadly flash of radioactive lightning that would instantly kill all sensate things. And although this is admittedly purely speculative, no one dare say that such a discovery will not be made, not when one remembers how remote and unlikely a process such as fission seemed to be just before it was made.

Though many of the great discoveries came about as the result of chance, they came because, as Pasteur said, “chance favors the prepared mind.” Actually they came largely through the intellectual synthesis of what had originally appeared as unrelated phenomena or concepts. When Faraday discovered the principle of electromagnetic induction, he established for the first time that electricity and magnetism, looked upon since prehistoric times as two separate and distinct phenomena, were actually only two aspects of one basic natural force, which we know today as electromagnetism. This great intellectual synthesis led directly to the age of electricity and all its wonders. About thirty years later the great Scottish physicist James Clerk Maxwell demonstrated that electromagnetic action traveled through space in the form of transverse waves similar to those of light and having the same velocity. This revealed the existence in nature of electromagnetic waves, better known to us today as radio waves. About a quarter century later the great German-Jewish physicist Heinrich Hertz not only produced these electromagnetic waves but showed that they are propagated just as waves of light are, possessing all other properties of light, such as reflection, refraction, and polarization. This led directly to wireless telegraphy and telephony, radio and television, radiophotography and radar.

When Einstein, in his special theory of relativity of 1905, united matter and energy in one basic cosmic entity, the road was opened to the atomic age. Yet Einstein was never satisfied and has devoted more than forty-five years of his life to the search for a greater, all-embracing unity underlying the great diversity of natural phenomena. In his general theory of relativity of 1915 he formulated a concept that encompasses the universal law of gravitation in his earlier synthesis of space and time, of which matter and energy were an integral part. This synthesis, wrote Bertrand Russell in 1924, “is probably the greatest synthetic achievement of the human intellect up to the present time. It sums up the mathematical and physical labors of more than two thousand years. Pure geometry from Pythagoras to Riemann, the dynamics and astronomy of Galileo and Newton, the theory of electromagnetism as it resulted from the researches of Faraday, Maxwell, and their successors, all are absorbed, with the necessary modifications, in the theories of Einstein, Weyl, and Eddington.

“So comprehensive a synthesis,” he continued, “might have represented a dead end, leading to no further progress for a long time. Fortunately, at this moment quantum theory [the theory applying to the forces within the atom] has appeared, with a new set of facts outside the scope of relativity physics [which applies to the forces governing the cosmos at large]. This has saved us, in the nick of time, from the danger of supposing that we know everything.”