by
Damien F. Mackey
“Towards the end
of 1915, Einstein produced his masterpiece: the general theory of relativity.
This year, physicists
are celebrating the centennial of Einstein’s theory. They are looking
back on the theory’s origins, its growing pains, how it is holding up. And
they are devising experiments to test the theory under ever more exotic
conditions, to see if, or where, it may falter. And most of all they are
looking ahead, pondering the next theory – one that can reach even further
than Einstein’s, by incorporating the other great idea of 20th century
physics: quantum mechanics”.
Dan Falk
Cosmos, Issue 65 (Oct-Nov 2015), p. 52
Introduction
Recently
I tuned in to watch an SBS TV documentary with the title “Inside Einstein’s
Mind”, and I was intrigued to learn that Einstein had managed, with his theory
of General Relativity, to unlock the laws of nature.
This
documentary is being promoted in the following laudatory terms:
In
November 1915, Einstein published his greatest work: General Relativity, the
theory that transformed our understanding of nature's laws and the entire
history of the cosmos. This documentary tells the story of Einstein's
masterpiece, from the simple but powerful ideas at the heart of relativity, to
the revolution in cosmology still playing out in today's labs, revealing
Einstein's brilliance as never before. (From the US) (Documentary) G CC
One had
to marvel at Albert Einstein’s mathematical skill, his ability to think outside
the square and to embark upon a new course, his powers of concentration, and
his tenacity.
Dan Falk
muses about the intense effort that Einstein must have put in:
A century ago Einstein sweated blood to
give us his mind-bending theory of gravity. As technology caught up, his
predictions were verified, one by one. Now only gravitational waves remain.
BEETHOVEN
SPENT MORE THAN 16 hours a day at his piano, sometimes composing four musical
works at once. Immersed in his task, he would become feverish, often dousing
himself with water that soaked through the floor into the apartment below.
If
we could time-travel to Berlin between 1905 and 1915, we would likely find Albert
Einstein at the height of his powers, in a similarly febrile state. Yet he
pushed on with his equations knowing, as he hinted in the letter to his
cousin, that “great things” were within his reach.
But did Albert
Einstein really succeed in coming to grips with the laws of nature and the
origins and history of the cosmos?
Is the
warp and woof of Einstein’s universe, with its lumpiness and bumpiness, really
the way that the universe is, or the way of Einstein’s own imagination?
Can
God be defined by an elaborate physico-mathematical equation?
Gavin
Ardley well summed up the nature of the new theoretical physics in his classic
book, Aquinas and Kant: the
foundations of the modern sciences (1950).
I take here a part of his:
Chapter IV
THE SIGNIFICANCE OF PROCRUSTEAN
SCIENCE
The
‘Otherness’ of Modern Physics
Post-Galilean
physical science is cut off from the rest of the world and is the creation of
man himself. Consequently the science, in itself, has no immediate metaphysical
foundations, and no metaphysical implications, in spite of popular beliefs to
the contrary. These beliefs arise from the failure to realise the science’s
‘otherness’, that it belongs to the categorial order and not to the real order.
Only that
which belongs to the real order is directly linked with metaphysics. The
ancient and medieval science of physics belongs to this real order, and is, in
principle, an integral part of philosophy in general. It has
metaphysical foundations and metaphysical implications. [Footnote: This is not
to say that all the particular Aristotelean doctrines of the Earth, the Skies,
the Heavens and so on, are essential to Aristotelean metaphysics. They are
integrated with metaphysics only in their general intention, and not in
particular formulation. They could be modified without necessitating any
change in metaphysical principles since the principles of metaphysics are
founded on more general grounds. Many of the particular Aristotelean opinions
about phenomena were abandoned in the 17th century with the
increasingly detailed knowledge of Nature. Galileo’s Dialogues on the Two
Great Systems of the World is a classic account of this revision of
detailed theories of phenomena. Galileo himself, unlike many of his more
extravagant followers, generally pursued this revision with considerable
moderation. (See Ch. XVII). He is careful to distinguish what is true an
abiding in Aristotle from what is erroneous and non-essential.]
But the ‘new
science’ shifted across by degrees into the categorial order and consequently
severed its immediate link with metaphysics. Few people were aware of this,
[Footnote: See Ch. XVII on the enlightened views of such men as Cardinal
Bellarmine in the very early days of the movement. Unfortunately, Bellarmine’s
wise observations were forgotten in later years. See, too, Ch. VI on Immanuel
Kant, who held the clue in the hollow of his hand, but by excess destroyed it.]
least of all the physicists themselves. The general run of physicists and
philosophers have gone on writing learned works on the metaphysical
foundations, and more particularly the metaphysical implications, of modern
physics, oblivious to this change of character. If the theory of the nature of modern
physics put forward in this book is correct, then both these enquiries are
vain.
Works on
the supposed metaphysical foundations of modern physics may have some value
however, even if not in the sense intended by the authors. For, although
logically the supposed foundations are not there, yet psychologically the
metaphysical background may well have prompted the physicist to introduce this
or that Procrustean bed. It is one of the sources of inspiration.
[Footnote: See Ch. XI on Scientific Method.] Such enquiries then are of great
interest to the historian of science as indicating one possible factor which
led physicists to do what they in fact did. But they do not in any way provide
a metaphysical foundation for the science, since a categorial science has no
such foundation, dwelling apart, as it does from the real world. [Footnote:
Such a work is the valuable study of Burtt: The Metaphysical Foundaions of
Modern Science (London, 1925). We might say that the significance of this
work is not logical, as Burtt apparently intended, but psychological and
historical. It is significant that Burtt practically ignores Kant and his
Copernican revolution, which is of vital importance in this matter and leads to
quite different conclusions from Burtt’s (see Ch. VI).
Reference
should be made to E. W. Strong: Procedures and Metaphysics (Univ. of
California Press, 1936) for an examination of the origin of modern physics from
the non-metaphysical point of view advocated in this work. Strong writes (pp.
10-11):
The operational
autonomy of science and the irrelevance of the metaphysical tradition was a
conclusion arising from, rather than being a premise leading to, the present
study. The theory with which the inquiry began was not confirmed by the
evidence, for let it be confessed at the outset that the original intention was
to consolidate the claim that the Platonic tradition was the metaphysical
godfather of modern scientific thought. The study of the scientific work and
opinion of the early-modern period conjoined with a correlated study of the
mathematical aspect of the Platonic tradition revealed that the original theory
was untenable. The problems of mathematicians and physical investigators were
found to be methodological rather than proceeding from, or based on, metaphysical
concepts. The meaning of concepts employed by mathematicians and scientists in
their work was found to be established in the limited operations and subject
matter constituting their science. The conclusion finally driven home was
the conviction that the achievements of Galileo and his predecessors were in
spite of rather than because of prior and contemporary metaphysical theories of
mathematics.
This
contention that there are two lines of activity, one of autonomous procedures,
and the other of metaphysics, is diametrically opposed to Burtt’s thesis of
homogeneity. Strong goes on to develop it with a wealth of historical evidence.
Strong’s conclusions from his examination of the origins of modern
mathematical-physical science in the 16th and 17th centuries lend
powerful support to our basic contention that there are two orders: an
autonomous order of physico-mathematical science, and a real order which is the
province of metaphysics. The contention as advanced here is founded on an
examination of the nature of physical science as we have it today. Strong’s
historical examination of origins is complementary to, and confirmatory of, the
present work.]
While
discussions of the metaphysical foundations of modern physics are comparatively
rare, discussions of its supposed implications are extremely popular. In fact
the implications of science are the happy hunting grounds of generations of
philosophers, and physicists turned amateur philosophers.
Anxious
theologians scan the latest scientific theories to see if they do or do not
support the existence of God. Grave scientists issue their pontifical
pronouncements. Sir James Jeans tells us that God is a great mathematician;
Einstein says ‘God is slick but not mean’; Laplace, answering Napoleon who
taxed him with not mentioning God in his Mécanique Céleste, said: ‘I
have no need of that hypothesis’.
Puzzled
philosophers delve into the intricacies of the Heisenberg uncertainty principle
to determine if man does or does not possess free will, or to see if the law of
causality remains valid, or if it has to be replaced by statistical
probability.
[Footnote:
As representative of a multitude of contemporary philosophers, let us quote one
of the most acute, John Wisdom:
In
general philosophers concern themselves with paradoxes arising from facts that
come under their observation. It is important that they should be alive to the
paradoxes arising from quantum facts. Such facts cannot be shelved as merely
technical or as belonging to a special department; they are facts along with
all the other more familiar facts about nature they are no less real because
revealed by complicated laboratory apparatus than are those revealed by the
human eye. (Mind, Jan. 1947, p. 81)
These
remarks of Wisdom’s are largely vitiated by the author’s failure to take into
account the Procrustean character of physics. He is tacitly assuming a realist
theory or a passive phenomenalism (Ch. XVIII). ….
As an
amusingly ironic account of the extravagances into which popular opinion is led
by hypostatising the world of physics, let us quote from Aldous Huxley’s Time
Must Have a Stop (London, 1945), Ch. 8.
‘As I was
saying, Mr Barnack, everyone ought to know something of Einstein’.
‘Even
those who can’t understand what he’s talking about?’
‘But they
can, the other protested. ‘It’s only the mathematical techniques that
are difficult. The principle is simple – and after all, it’s the understanding
of the principle that affects values and conduct’.
Eustace
laughed aloud.
‘I can
just see my mother-in-law changing her values and conduct to fit the principle
of relativity!’
‘Well of
course she is rather elderly’, the other admitted. ‘I was thinking more
of people who are young enough to be flexible. For example, that lady who acts
as Mrs Gamble’s companion …’
‘…
Mathematically speaking, almost illiterate’, the young man was saying. ‘But
that doesn’t prevent her from realizing the scope and significance of the
Einsteinian revolution’.
‘And what
a revolution’, he went on with mounting enthusiasm. ‘Incomparably more
important than anything that had happened in Russia or Italy. For this was the
revolution that had changed the whole course of scientific thinking, brought
back idealism, integrated mind into the fabric of Nature, put an end for ever
to the Victorians’ nightmare universe of infinitesimal billiard balls’.
‘Too
bad’, said Eustace in parenthesis. ‘I really loved those little billiard
balls’.]
“Difficulties
of a common sense and philosophical nature are frequently encountered in the
acceptance of fundamentally new principles of physics, as e.g. on the
introduction of relativity and quantum theories. These difficulties should not
be experienced henceforth when it is realised that, in spite of misleading
terms, the physical principles are not about the real world which we
know so well. The physicist should become more conscious of the power he
possesses to mould his subject when he is fully aware of his autonomy”.
Gavin
Ardley,
Aquinas and Kant
------------------------------------------------------------------------------------------------------
It
is clearly the physicist who is imposing the conservation laws and making
Nature fit, and not vice versa as the older logicians thought.
------------------------------------------------------------------------------------------------------
Thus
Gavin Ardley describes the essentially artificial nature of the modern
theoretical physics (Aquinas and Kant: the foundations of the modern sciences, 1950).
The above quote is to be found in his:
Chapter
III
THE
NATURE OF MODERN PHYSICS
Procrustes at Work
As far as practice is concerned it would hardly be
an exaggeration to say that the physicist holds on to a law of physics until he
gets tired of it. To him it is a tool which he can use when he pleases, and
discard when he pleases. Having discarded one theory he can pick up another, or
perhaps even use the two at once, as has happened on more than one occasion.
His choice is determined by his own habits and convenience. As a rule no single
experiment can establish a law of physics on any firm basis, i.e. provide a
compelling reason for the physicist to recognise it. Similarly no singe
experiment can ever demolish a theory, i.e. compel the physicist to relinquish
it there and then. This, of course, is quite at variance with the classical
theory of the science.
Let us take a typical example and see to which
pattern it conforms. The corpuscular theory of light in the hands of Newton was
a fairly satisfactory theory of the nature of light. But with increasing
interest in the phenomena of optical interference it became more and more
difficult and troublesome to hold the corpuscular theory, while the wave theory
became more and more attractive. No single experiment could finally demolish
the corpuscular theory. It was only necessary to introduce more and more auxiliary
hypotheses and the corpuscular theory, and its interpretation of the phenomena,
could have been retained indefinitely. But in time most physicists came to feel
that it was not worth while, that it had become too cumbersome. They grew tired
of the corpuscular theory, and early in the 19th century they turned to what
had by then become the much simpler wave theory, and thenceforth interpreted
the phenomena in terms of the latter.
However, at the end of the 19th century
and the beginning of the 20th century, with new discoveries, a
greatly modified corpuscular theory was revived under the name of the quantum
theory. The quantum theory and the wave theory were employed conjointly for a
number of years until finally both were subsumed in the theory of ‘wave mechanics’.
Throughout the history of the theories of light
there is very little of the ‘observing uniformities and generalising them into
laws’, and very much of the physicist as the master operating successive
Procrustean beds.
A particularly striking case of the a priori
nature of physical theories and laws is provided by the particle known as the
neutrino. In the beta-particle decay of radio-active nuclei, a continuous
spectrum of beta-rays is emitted. This continuous spectrum provides one of the
major problems of contemporary physics. A consideration of the process shows
that either the classical laws of the conservation of energy and angular
momentum are not obeyed by individual nuclei, or else another particle,
hitherto unknown, which Fermi called the ‘neutrino’, is emitted along with the
electron. This new particle is given just the spin and energy needed to make up
the discrepancies, but it will have no charge and practically no mass.
Consequently its detection would be difficult by any direct means. Nevertheless
most physicists follow Fermi in postulating the neutrino, simply because it
saves the conservation laws. It is quite ad hoc, but it prevents the
laws being violated. The physicist’s Procrustean rôle is quite apparent. It
is clearly the physicist who is imposing the conservation laws and making
Nature fit, and not vice versa as the older logicians thought.
It is the same throughout physics: the physicist is
the law-giver. He makes and imposes the laws, and has power to enforce them or
withdraw them as he sees fit.
Again, reverting to the early days of modern
physics, we may ask: how did Galileo know that in the absence of resistance to
motion all bodies would fall towards the Earth with the same acceleration? How
did Newton know his laws of motion to be true; in particular, that every body
continues in its state of rest or of uniform motion in a straight line unless
compelled by external force to change that state? Did Galileo and Newton
discover these law or invent them? Are they ‘natural’ or Procrustean? When we
consider the mater we are driven to put them in the latter category.
Galileo can hold to his contention as long as he
pleases by attributing departures from equal acceleration to resistances to
motion. But how do we know there is resistance to motion? By reduced
acceleration! Similarly Newton preserves his first law by attributing any
departure from uniform rectilinear motion to an impressed force. But how do we
know when there is such a force? By observing a departure from uniform rectilinear
motion!
On this procedure it is impossible ever to disprove
the laws so long as physicists choose to retain them. [Footnote: Cf. Ch. X on
the alleged non-existence of badgers.]
Try to grasp the laws intellectually, as laws of
Nature, and we are in a vicious circle from which there is no escape. Regard
them as Procrustean beds and their function is clear.
Let us turn now from particular theories to a wider
horizon. Here we will find some illuminating situations.
Ardley
here turns to a consideration of experiments relating to the Special Theory of
Relativity:
One instance which must give everyone food for
thought is the case of the American physicist, D. C. Miller. It is well known
that one of the strongest experimental grounds for the special theory of
relativity is the Michelson-Morley experiment performed in the year 1887. This
celebrated experiment was designed to detect the motion of the earth through
the ether. The result was negative. No relative motion could be detected.
The negative result of this experiment has become fundamental to a great deal
of modern physics.
But the interesting sequel is that since then
Miller has made an exhaustive investigation, and has persistently achieved positive
results in his repetition of the principle of the Michelson-Morley experiment.
[Footnote: See Miller, D. C. : Reviews of Modern Physics, 5, 203,
(1933).] However his has been a voice crying in the wilderness, for the
physicists have heeded him not. Special relativity is so firmly entrenched that
any fundamental change at this stage is unthinkable. In other words special
relativity has hardened into a Procrustean bed to which physicists are clinging
tenaciously, and in terms of which they are interpreting the world. The
physicists are not inclined to give up their bed at present, Miller or no
Miller. ….
One
of the beauties of Ardley’s thesis is that it clearly demonstrates the
legitimacy of metaphysics as a study quite autonomous from modern theoretical
science.
The
proponents of Scientism, which modern phenomenon Wikipedia well defines as (https://en.wikipedia.org/wiki/Scientism)
“a belief in the universal applicability of the scientific method and approach, and
the view that empirical science constitutes the most "authoritative" worldview or the most valuable part of human learning—to the
exclusion of other viewpoints”, have thought themselves entitled to announce
the downfall of metaphysics as an irrelevance. Ardley, still in
Chapter III makes the distinction between the two disciplines:
The Physicist and the Philosopher
…. A generation ago, when ‘relativity’ was
prominently before the public eye, disputes about space and time between the
philosophers and the relativity physicists were well nigh interminable. But the
considerations put forward here show that such disputes are baseless. The
parties were all unknowingly, discussing different things. The mistaken belief
that the physicists are talking about the real space, time, and matter of the metaphysicians,
arises in part because the physicists still use these names, but without
the literal reality.
A recent writer on electromagnetic theory, J. A.
Stratton, approaches his subject in somewhat the spirit of the foregoing.
Stratton commences: ‘By an electromagnetic field let us understand the domain
of the four vectors E and B, D and H’. He does not attempt to draw a red
herring across the trail in the traditional manner by professing to derive
these entities, E, B, D and H (a domain, we might say, of mental ‘artifacts’
[Footnote: On artifacts, se Ch. XVI.]). He leaves it to the sequel to give what
pragmatic reasons he can find for inducing people to take an interest in the
domain of E, B, D and H. Stratton puts a completely arbitrary system before us.
When we ask Why? What is it all about? What is the good of it? he will answer
by pointing to its pragmatic sanctions, in so far as he may be able. And the
pragmatic sanction is its power of co-ordination and prediction. The system
does not profess to tell us anything immediately about the nature of the real
world.
Stratton’s mode of casting physics might well serve
as a model for other writers. It would banish much of the present obscurity.
If we wish to sum up modern physics in a phrase, we
could call it ‘a priori pragmatism’. This is a far cry from the old
classical empiricist doctrine, which professed to build up from Nature. In fact
it is precisely the reverse, since it makes contact with ‘Nature’ not at the
beginning, but at the end. [Footnote: It is here that the deductive system of
modern physics and the deductive system of Plato in the central Book of the
Republic differ so fundamentally, in spite of a superficial resemblance. For
with Plato the first principle, the Form of the Good, is grasped intellectually
and intuitively. Consequently the whole hierarchical system is supremely
grounded on Nature at the beginning. There is nothing of this in the
hierarchical system of modern physics, where the sanction is always at the
extremities not at the apex.]
Let us carry on Stratton’s principles, and say:
‘the world of modern physics is the domain of the artifacts m, s, t, F,
E, B, D, H, etc., etc’. This leaves open the question of the relation of this
world of artifacts to the real world. This is for the philosopher to determine,
not the physicist. ….
Dan Falk,
writing for Cosmos, continues here:
But
for now, Einstein’s theory reigns supreme. “There’s not a single experiment
that has gone against it – at least, not one that’s ever been confirmed,” says
Clifford Will, a physicist and general relativity expert at the University
of Florida in Gainesville. “It’s passed every test with flying colours”.
However,
before we become over-excited about Einstein’s amazing strike rate as according
to Falk and Will, recall what was previously observed about the rôle of the modern physicist:
…. The physicist’s Procrustean rôle is quite
apparent. It is clearly the physicist who is imposing the conservation laws
and making Nature fit, and not vice versa as the older logicians thought.
It is the same throughout physics: the physicist is
the law-giver. He makes and imposes the laws, and has power to enforce them or
withdraw them as he sees fit.
Again, reverting to the early days of modern
physics, we may ask: how did Galileo know that in the absence of resistance to
motion all bodies would fall towards the Earth with the same acceleration? How
did Newton know his laws of motion to be true; in particular, that every body
continues in its state of rest or of uniform motion in a straight line unless
compelled by external force to change that state? Did Galileo and Newton
discover these law or invent them? Are they ‘natural’ or Procrustean? When we
consider the mater we are driven to put them in the latter category.
Galileo can hold to his contention as long as he
pleases by attributing departures from equal acceleration to resistances to
motion. But how do we know there is resistance to motion? By reduced
acceleration! Similarly Newton preserves his first law by attributing any
departure from uniform rectilinear motion to an impressed force. But how do we
know when there is such a force? By observing a departure from uniform
rectilinear motion!
The same
sorts of questions may be asked of Einstein’s General Theory of Relativity and
why experimentation has universally been confirming it.
We now
continue with Gavin Ardley’s incisive analysis of the activities of the modern
physicist (Aquinas and Kant: the foundations of the modern sciences, 1950),
still in his:
Chapter
III
THE
NATURE OF MODERN PHYSICS
Physics
and Nature
The world of modern physics is not the natural
world. It is a remote domain of artifacts more removed from the world of Nature
than the worlds in which Mr Pickwick and Hamlet dwell. The world of physics is
austere and exacting, but withal a world of deep and abiding beauty. It is this
aesthetic quality, perhaps even more than the satisfaction of intellectual
curiosity and the desire for power, which explains its hold on its exponents.
The beauty of pure mathematics has been recognised at least since the days of
Plato. Pure physics has this beauty too, and in addition an intangible quality
peculiar to itself which is well known to those who have entered its inner
temples. This, rather than the exploration of nature, must be the physicist’s
apology.
But it may well be asked now: what is the relation
between physics and Nature? If physics dwells apart, how does it come into
contact with Nature. And furthermore, it may be asked, why is it so successful?
In a general way, the solution of the first part of
this question lies in the fact that the process of systematic experiment is
selective and transforming. Hence it is that the transition is made from Nature
to the abstract world, and vice versa. This is the link between the two
worlds.
As regards the second question – why, if physics is
an abstract and arbitrary system, is it so successful? – we might ask in
return, what is the standard of success? How much more or less successful
physics might have been had it been developed in different ways from the way it
was in fact developed, we do not know. If the net dragged through the world by
the physicists had been quite different, the outcome might have been very
different too. It may have been much more successful, or much less so. We have
no standard of comparison for success, so the question is scarcely profitable.
In discussing success it may be helpful to compare
together two different branches of physics. The classical mechanics as applied
to the solar system was generally regarded as a dazzling success. But on the
other end of the scale the theory of electromagnetics is regarded today by most
students of the subject as being in a state of well-nigh hopeless confusion,
although with experience it can be made to work moderately well. Evidently some
wrong turning was made early in the development of this latter branch of
physics, and with the root trouble, whatever it is, firmly entrenched, the
subject appears to be growing in disorder and chaos rather than improving.
Evidently it would be better to start afresh from the beginning and drag some
quite different net through the world in this particular realm.
Such considerations as these should give us pause
before we speak lightly of the ‘success’ of physical science.
A variant on this question Why if arbitrary then
success? is to insist that if a law or theory enjoys success, then, in the same
measure, it is probable that Nature is really like the situation envisaged by
that law or theory. E.g. if the law of Gravitation is well established in
physics, then there must really be this Gravitation in the world, and so on. In
answer to this objection we cannot do better than quote the words of
Wittgenstein in his Tractatus Logico-Philosophicus, where he propounds
much the same doctrine concerning the laws of physics as we have in this
chapter. In the course of a most penetrating discussion of the subject he remarks:
The fact that it can be described by Newtonian
mechanics asserts nothing about the world; but this asserts something,
namely, that it can be described in that particular way in which as matter of
fact it is described. The fact, too, that it can be described more simply by
one system of mechanics than by another says something about the world. [Tractatus,
6.342.]
If the laws of physics were really found in
the world, then the laws would tell us something about the world. But if the
laws of physics are superimposed on the world, then the laws themselves
tell us nothing about the world. [Footnote: This incidentally provides the
solution to the controversy which raged throughout the Middle Ages concerning
the status of the various systems of astronomy. See Appendix.] Only the
character of the particular description which we effect in terms of the
super-imposed law has any bearing on the world. It is only in this second order
manner that we make contact with the world. ….
Hence there is no foundation for the assertion that
in modern physics a law or theory, if successful, tells us what Nature is like.
This
is a most important conclusion.
The
Practice of Physics
Apart from the possibility of a far-reaching
hyper-physics being developed, these new views about physics are not likely to
make much direct difference to the practice of physics. But indirectly
they may have a considerable effect. The delusion that modern physics is
directly concerned with Nature, with space, time, matter, and so on, has
undoubtedly hampered the growth of the science considerably during the last few
centuries. The physicist should now become bolder when he realises that he, not
Nature, is at the helm. He should more easily be able to cast aside old ties
and inhibitions. Difficulties of a common sense and philosophical nature are
frequently encountered in the acceptance of fundamentally new principles of
physics, as e.g. on the introduction of relativity and quantum theories. These
difficulties should not be experienced henceforth when it is realised that, in
spite of misleading terms, the physical principles are not about the
real world which we know so well. The physicist should become more conscious of
the power he possesses to mould his subject when he is fully aware of his
autonomy.
However, apart from this increased freedom,
practice is not going to be altered one whit. The physicist spends most of his
time applying the discipline he has so laboriously acquired. For this there is
little need to know much about the whys and wherefores of the discipline. The
main thing is to be able to use it. It makes little difference to the practice
whether the laws of physics are a priori or not. In fact we usually find
that the best experimental physicists are quite poor at discussing the nature
of their subject. This is an observation which applies not only to physics, but
is almost as true in literature, music, and art. The poet, the musician, and the
painter are often the last people to go to for an intelligible account of the
foundation of their arts. The have a divine talent, they live the life. That is
enough. It is for others, with aesthetic sensibilities, but of a more
philosophical turn of mind, to enquire into the nature of the arts. Returning
to the physicist: in his laboratory, with his white coat on so to speak, it is
scarcely exaggerating to say that he has some of the attributes of a robot and
some of a slave. And quite rightly so. This is his function, and if he
considers physics worth while the physicist must be prepared to subject himself
to his stern taskmaster. He has a task to perform, and the best physicist is he
who performs it most diligently.
This applies to by far the greater part of the
average physicist’s working life. But occasionally he is called upon to
promulgate a new theory or law. In its formulation he needs to exercise his
imagination, and theoretical physicists in particular often combine an
imaginative gift of a high order with their more ordinary capacity for routine
discipline. This imaginative power has come particularly to the fore in recent
times. Dirac’s amazing theory of the positive electron is a good example.
[Footnote: Very briefly, according to Dirac the whole universe is filled with a
continuum of electrons of negative energy, i.e. of negative mass. A g-ray
quantum, of energy greater than one million electron-volts, may impart its
energy to one of these electrons. The electron leaves the continuum, acquires positive
mass, and is observed as an ordinary negatively charged electron. At the same
time the quantum disappears, and the hole left in the continuum is the positive
electron.
This phenomenon of the production of positive and
negative electron pairs by the annihilation of a quantum may be observed in the
Wilson Cloud Chamber.
After a short lapse of time the positive electron
will meet a negative electron. The negative electron will fall into the hole,
which is what the positive electron consists of. In this way both electrons are
annihilated and the energy re-appears as a one million-volt quantum.] With the
wider spread of the Procrustean interpretation of physics, and the consequent
increased emancipation of the subject, we may expect this imaginative element
in physics to flower even more luxuriantly.
The whole question of the physicist’s imaginative
powers, and hence of the origin of the forms of laws and theories, is one which
has been all too little discussed in histories of physics. [Footnote: See Ch.
XI on Scientific Method.]
The
Rôle of Physics
The new orientation to the subject is significant
as regards the status of physics in the world. It is likely to make a
considerable difference in the rôle of physics in man’s thinking, whether he
believes physics is wresting out the secrets of Nature, or whether he believes
the whole thing is quite artificial, and only of utilitarian and aesthetic
significance, valuable as these latter may be.
When it is generally realised that modern physics
is not really telling us anything of the world about us, in other words that
the ontological status of the world of physics is very low, then we might
expect that physic will be allotted to its proper place as an auxiliary to life
and a fascinating intellectual exercise. Then, being released from our
self-imposed shackles, we will be free to turn our attention elsewhere in
search of the real world. There we will find real matter, time, and space. We
learn more about time from the simple words of the hymn:
Time, like an ever-rolling
stream,
Bears all its sons
away.
than
from any text-book of physics.
This mental freedmen will be good for the layman,
and it will be good too, for the physicist, in so far as he is a man. For the
physicist is not always in his laboratory disciplining himself. Sometimes he
emerges into the real world of everyday life with its warmth and colour, hopes
and fears, its beauty, love, laughter, tears, its good and its evil. This is a
world of values, quite different from the monotone of physics where values have
been systematically excluded. In this real world the physicist finds modern
physics but a broken reed. Of course, no human being is completely devoid of
the knowledge of real life. The complete and utter physicist could not continue
to live. The physicist – like nearly all scientists – must lead something of a
dual existence. He leads one life in the laboratory and another and quite
different life outside it.
Finally, we must allude to a subject which will be
discussed more fully in another chapter. [Footnote: Ch. X.] With the change in
the status of physics we may expect a change in the prevailing fashions in
contemporary schools of philosophy. Some of the most influential of these
schools are ultra-empirical and positivistic in tone. The model for their
thinking is, by and large, physics. They try to map put out the world along
lines appropriate to physics. For everything other than physics the result is
incredible barrenness.
Now that we see physics in a different light,
perhaps the philosophical craze to ape the physicist will die out, and
philosophy can resume its proper rôle of comprehending the real world in so far
as that is possible to us. Metaphysics has been held up to scorn and ridicule
by many since the rise of modern physical science. But now we see that physics
does not deal with the real world at all. This is the province of metaphysics.
To
scorn metaphysics in the name of modern physics is to misunderstand the
situation. Metaphysics should thus come back into its own again, once physics
has been relegated to its proper place.
