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SomethiM

Called

Nothing

Pny;K=~ \4:Ullll:

Whdtlslt?

HeLfTO

no HMeHH

HH4TO

First published 1986

Revised from the 1983 Russian edition

Ha anenuiicnou sieune

© M3~aTe:IbCTBO «3HaHlIe», 1983 © English translation, Mir Publishers, 1986

Preface

You are about to begin a book on science for the gener- al reader. It deals with the history of mankind's ideas on the Void, that great emptiness now called a physical vacuum. We know today that^ the^ properties of vacuum are much richer than those of any other kind of matter known to science. A wide diversity of fields, particles and much, much more exist in a vacuum. The more we find out about vacuum the more complex it seems to be. The properties of the universe around us are governed to a substantial degree by the properties of vacuum. We can say that the laws of physics are "inscribed on vac- uum". Quite another matter, however, is that we do not yet know for sure in what way these laws are imprinted there. Some things we do know for certain; others are still 1110re or less guesswork. But it is already clear that all electrons are absolutely identical by virtue of the proper- I it's of vacuum, as are all protons and any other particles or ('aeh definite kind. ~cience writing is frequently devoted to matters that are known with certainty and forever. The reader bowls along a paved highway that passes through country known down to the finest details. This book treats of a frontier of our knowledge and the poorly explored terri": tory beyond it. We cannot be sure that the "reconnais- sance data" that have been secured are faultless, or even I ha t the front line has been accurately plotted. But, on I he other hand, there is no need to denigrate the knowl- pdge we already possess. Much on our map is correctly shown and shall remain there for all time. By no mere chance have certain advances in vacuum theory won their discoverers Nobel Prizes in recent years. The present book relates the history of views, the de- vvlopment of ideas, often ones that are still in the mak- ing. It is, of course, more difficult to read such a book, hut, in my opinion, much more interesting. The choice of these subjects is the more important because science writing is intended, in essence, primarily for young peo- ple. Hence, it can and should deal with the fields of sci-

Contents

 - Preface - To the Reader 

• DOES THE V~OID EXIST?
• THE FIFTH "ELEMENT" - In Place of Emptiness - The Genealogy of the Ether - An Answer to All Problems - Grandeur and Fall of the Ether
  • xoruixc j\ND SOl\1ETHING - Above the Dirac Sea - An Ocean Beyond the Ocean - of the Simple Simplicity of the Complex and the Complexity - All the Powers of the World - Variable Vacuum - La\vs and Forbiddances - Mathematics for Physics - l'he Fruitbearing Void - Beyond the Power of Even Vacuum - Around and About the Neutrino - A Physics Laboratory in the Ocean Depths - Amazed by Our Own Achievements - and Differ in What Ether and Vacuum Have in Common
    • NOTHING AND EVERYTHING - Nothing Beyond the Sea of Dirac or Everything is - Canvas and Paints '

8 Contents

Is Everything Vacuum? 190 Notes on the Margin of Our Picture of the ~Vorld 198 On the Brink of Remarkable Discoveries 206 In Place of a Conclusion 212

10 To the Reader

Hence many laws that govern our world are dictated,

in the final analysis, by what is called the symmetries of

vacuum.

What's more, the elementary particles themselves are

frequently thought to have been created out of vacuum.

It may be that many puzzles of space and time have so-

lutions concealed in the profound properties of vacuum.

It may well be that space and time themselves can be

called forms of existence of vacuum, if you take into ac-

count the true significance of the role that the physical

vacuum plays in our world.

The history of the metagalaxy is, in fact, the history

of the vacuum. There is hope that we shall find the key

to many, very many problems of the past, present and

future of the universe in what we still call by its Latin

name: vacuum. I am sure that by now you like me are

amazed by the commonly known translation of this La-

tin term: emptiness, i.e. nothing.

Up-to-date science, conducting research into the mi-

croscopic world and into space, into solid-state and ele-

mentary particle physics, and into nuclear physics and

gravitation theory, finds it equally inevitable, though

Irom different aspects, to take into consideration, and con-

sequently investigate, the properties of vacuum as a spe-

cial and extremely vital variety of matter. A radiophysi-

cist and a nuclear specialist, a historian of science and an

investigator of superconductivity all told the author and

with the same conviction that one of the most fascinat-

ing and promising trends in modern physics is the study

of vacuum. They maintained that this field may yield

solutions to a great many problems of physics, and that

advances in science will evidently be accompanied by a

more and more profound understanding of what this great

Something called Nothing actually is.

In the march of science, the phenomena being investi-

gated are related by laws that are based either implicitly

or explicitly on fundamental scientific concepts. From the

very outset, emptiness was also included in these Iew

most essential ideas of science. The Void preoccupied the

keen mind of Aristotle" tormented Descartes, worried Ga-

lileo and bothered Newton. Conceptions of the void have

To the Reader 11

changed down through the centuries together with our concepts of the world as a whole, but they always played a leading role in our picture of the universe, even during the times when emptiness was considered to be impos- sible.

There are no useless discoveries I You must not tell a scientist to discontinue his research because it is unneeded today.... By scornfully discharging re- search that may now be abstract, but is actually levelled at unravelling the mysteries of nature and reproducing its phenomena, we run the risk of losing too much, because a knowledge of the unknown forces of nature is always followed by the mastery of these forces. Mikhail LA VRENT'EV

An apprehension of deep scientific problems plays an exceptionally vital role in understanding the world by man and in working out a true overall outlook. The idea of emptiness is one of these very general and deep con- cepts. It^ belongs,^ without^ doubt,^ to^ those^ general^ prob- lems without whose solution a scientist would, according to Lenin, be doomed to stumble over particular problems. Look how often the concept of emptiness has served as the touchstone for a new physical hypothesis or theory! Modern approaches to vacuum are not only important and instructive for philosophers and physicists. Its history, the history of emptiness, is also fascinating in itself and more generally, for it illustrates how man gains scientific knowledge. It can serve as a model for newer important solutions in physics and, moreover, in any field of science. Here, with striking clarity, we see historical continui- ty and the onward march of science, and the kinship of investigators separated by centuries and millennia. We can see here the ties of time that support the unity of mankind. You will not, of course, find in this book "the whole truth" about vacuum. And not just because the whole truth has not yet been uncovered. And not even because it would require a sizable library to set forth all the results

To the Reader 13

HS "thought experiments", "because all shades of mean-

ing by a clever number are conveyed", as a poet once

contended. In many up-to-date papers on physics, wheth-

or for the better or worse, words play the part, almost

everywhere, of only punctuation marks, separating one

system of equations from others, or of conjunctions that

link equations together. (But, mark you, conclusions

or a brief summary are always in words!)

In a story about science for the general reader, the

rnotto of a storyteller is the direct opposite to that of the

Iloyal Society and of all exact sciences. "Everything in

Words" might well be the motto blazoned on the shield

of one who resolves to write about science.

To a reader who opens this book with the hope of find-

ing out everything on the subject, I can only advise:

"Close it immediately!" Even what is already known by

science cannot be described by words alone, still less

what remains unknown. I have not presented exact proofs

that certain phenomenon in nature is truly- as described

here. Nothing can be proved with words alone. Proof

only comes from experimental results and calculations.

There is no way in such a book to follow a most exact

illustration of a most precise apparatus by a highly de-

tailed description of the appropriate experiment, but only

this would convince (or not) a specialist that all has

been done properly. In exactly the same way, we cannot

here merge brooks of mathematical formulas into the

abundant rivers of scientifically stated theories. But all

of this can be found in the books and articles addressed

to those who know enough to find out more, to those who

can translate by sight what is written in the universal

language of nature.

What you have before you is neither a textbook nor a

scientific monograph. I address myself to those who wish,

not so much to clear up details, but to gain some under-

standing of basic principles: the course and laws of de-

velopment of human thought as applied to the problem

of emptiness, the ether and vacuum; the cardinal differ-

ences in the solution of this problem down through the

ages; the conclusions of science based on experiments

and calculations, and, finally, the human aspect in the

14 To the Reader

acquisition of knowledge about physical reality. All of this, it seems to me, can be conveyed using only words. Moreover, only words will do.

In science, more than in any other human institu- tion, it is necessary to search out the past in order to understand the present and to control the future. John Desmond BERNAL

(^16) Something Called Nothing

take root in science. It was supplanted by the Latin word vacuum. Why? There were probably a great many rea- sons for this. It may well be that even such a matter, ir- relevant on the face of it, as the sound of the word, played its role.

There are, of course, no direct, or even indirect, rela- tions in the majority of cases between the meaning and sound of words, But still, we sometimes do' find an inter- dependence between the definition of a word and its com- bination of sounds. This has been demonstrated experi- mentally: most people correctly guess which of two words they hear in a language unknown to them means "heavy" and which means "light". The following is cited from a paper by L. .L. Kitaev- Smyk, who has a post-graduate degree in medicine: "In ancient oriental language systems, the sound u or ou sym- bolizes emptiness, disappearance and negation. In pro- nouncing this sound, a person must imagine a cavity formed in his mouth with its bottom seeming to sink lower and lower. This is evidently called for to facilitate the 'disappearance' of some emotional disturbance, thereby tranquilizing the nervous system". People who know the Russian language may have no- ticed that in the word poostota (emptiness) and the La- tin word vacuum, the u sound plays no small part. Did this happen by chance? I do not intend to follow in the steps of Romain Oira-Oira from the fairy tale for grownups called Monday Begins on Saturday by the science-fiction writers Arkady and Boris Strugatsky. Ro- main was engaged, in this book, in investigating the re- lation between the piercing properties of a glance (ca- pable, according to the tale, of boring a hole through a concrete wall) and the philological characteristics of the word concrete. Worthy of mention, however, is that the Chinese word for emptiness is kunshu, and in Japanese it is kuso or kuke. On the other hand, there is no u sound in many other languages in the word for empti- ness. Hence, the phonetic version for the change from kenon to vacuum is probably infeasible. Maybe the reason is that the majority of the ancient

Does the Void Exist? 17

Greeks, as you shall soon see, denied the very existence of the void? It was hardly worthwhile, they thought, for science to retain a term meaning something that could not be.

Many things in this world had to be discovered by man. These include both the void and the air. Air was, of course, discovered several centuries earlier. It was included among the basic materials that made up the world, being declared one of the four "elements" to- gether with water, earth and fire. The ancient philosoph- ers taught their disciples that everything in the world is made up of particles of one or several of these ele- ments. Somewhat later, a quesLion arose in Greek philosophy: can one find a place where there is no earth, no water, no air and no fire; is a genuine void possible? To pose a question to the ancient Greeks meant that they would certainly make every attempt to answer it right off the bat, firmly and almost always categorically.

Among the great things that are not within us, the existence of. "nothing" is the greatest. Leonardo da VINCI

Leucippus and Democritus in their 5th century B. C. reached the ultimate conclusion: everything in this world consists of atoms and the emptiness between them. Ac- cording to Democritus, to cut a piece of bread, sink a shovel into the soil, walk through the air and swim in a river are possible only because of the void between the atoms, themselves being indivisible. Hence, combinations of atoms forming the sea and clouds, stones and trees, and the bodies of animals and people are possible only thanks to the void. Only it can make way for motion, de- velopment and any changes in general. So, as we see, the void played no less role in Democritus' concept of the universe than a physical vacuum plays in ours. The solution proposed by Democritus was both ele- gant and simple. Not in vain has this philosopher been revered for twenty-five centuries. In our 20th century, the

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