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THE MARXIST REVIEW OF BOOKS
Manjit Singh explains why top scientists are more interested
in the quest for beauty than reality
Beautiful dreamers
- Superstrings: A theory of everything, PCW Davies
and J Brown (eds), Cambridge University Press, £5.95 pbk
- Dreams of a Final Theory, Steven Weinberg, Hutchinson
Radius, £1 6.99 hbk
- The Edge of Science, Richard Morris, Fourth Estate,
£8.99 pbk
- The God Particle, Leon Lederman with Dick Teresi,
Bantam Press, £1 7.99 hbk
Last October, particle physicists everywhere went into mourning when the
world's largest and most expensive piece of scientific hardware, the Superconducting
Super Collider (SSC), was finally killed off by the United States Congress.
The $11 billion particle accelerator, plagued by arguments over funding
since its inception, was abandoned in a bid to reduce the US budget deficit.
American Nobel laureates Leon Lederman and Steven Weinberg were particularly
devastated. Both were closely involved in developing the SSC and lobbied
congress to secure its funding. Both argue eloquently for the SSC in their
new books.
The purpose of the SSC, like the preceding generation of particle accelerators,
is to smash sub-atomic particles, by firing them at each other down ever-longer
tunnels. By breaking these particles ever-smaller, physicists learn more
about the building blocks that make up matter. It is hoped that the current
generation of particle accelerators will provide clues as to the basic structure
of the universe.
The construction of the SSC began in 1989 in Ellis County, Texas. It was
to have been a precisely engineered oval tunnel with a circumference of
53 miles. Instead, congress has earmarked $640m to shut it down and fill
in the 14 miles of tunnel already completed. This is nearly half the amount
that scientists from the European Centre for Particle Physics (CERN) are
seeking from their respective governments for CERN's latest particle accelerator,
the Large Hadron Collider.
When Leon Lederman began his term as president for the American Association
for the Advancement of Science in 1991, he wrote a report entitled: Science:
The End of the Frontier?. It summed up the contemporary mood. The title
was an ironic reference to the more optimistic report written in 1945 on
the future of US science, Science: The Endless Frontier.
Not every scientist will be mourning the death of the SSC. One highly respected
British theoretical physicist told me recently, 'personally, it wouldn't
worry me if the whole of CERN disappeared tomorrow or the SSC was never
built'. This is a fairly remarkable thought, given the extent to which governments,
on the advice of scientists, have invested in these projects so far.
He explained: 'I tend to be driven by the need for internal mathematical
consistency, there are enough problems in attempting to achieve this when
developing a theory.' The idea that physicists can dispense with the kind
of empirical data generated by the SSC and CERN, in favour of a more speculative
approach is not an isolated view among theoretical physicists.
As Richard Morris correctly points out in The Edge of Science: 'In
some fields theoretical speculation has advanced so far that...new concepts
will not be subjected to experimental scrutiny until sometime in the next
century.' As a result, he notes, 'some scientific speculation has recently
had a tendency to take a metaphysical character' (pxi). 'When one ventures
into previously unexplored regions, it is necessary to retain ties to the
known world', argues Morris, a trained physicist: 'At times, however, these
ties become tenuous. They are especially tenuous right now.'(pxi)
Nothing is more tenuous than superstrings, the latest candidate for a 'theory
of everything' - a theory that would unite all the known forces and particles
in nature into a coherent whole. Superstring theory is so far removed from
experimental testing, though, that it has been called a theory of the twenty-first
century accidentally discovered in the twentieth century.
Paul Davies and Julian Brown in Superstrings: A Theory of Everything?
present a collection of interviews with the adherents and opponents of the
theory. Although these include some of the most distinguished theoretical
physicists of the century, several of them would still benefit by reading
Morris. He unrelentingly points out the speculative and metaphysical character
of much modern physics from superstrings to quantum cosmology.
The interviews in Superstrings are entertaining. Especially if you
like to get your head around the possibility that everyday reality is the
result of hyperfine corrections to a 10-dimensional spacetime.
The theory of superstrings assumes that all observed particles are different
manifestations of the same fundamental entity. According to the superstring
idea, all particles which were previously thought of as little points are
in fact not points at all but basically little oscillating loops of string
which move through space. Superstrings are conceived as objects that vibrate
in 10 dimensions. The different levels of vibration correspond to the different
observed particles.
One of the major attractions of the theory is that it combines the two theories
which shape scientific knowledge of the physical universe: general relativity
and quantum mechanics. Quantum mechanics deals with the atomic and sub-atomic
domain, while general relativity is Einstein's theory of gravity and describes
the large-scale structure of the universe. The problem is that the two theories
are mutually incompatible. Yet the impulse for unity and simplicity is so
strong that theorists have pursued a quantum theory of gravity, without
success, for decades.
Superstring theory faces immense problems. It is highly abstract and difficult
to comprehend. The predictions it has made have been contradicted by the
available experimental evidence. The masses of particles predicted by the
theory do not correspond to the known masses. However, superstring theorists
argue that as the theory is developed it will produce the corrections that
are required to give the right masses. Existing particle accelerators cannot
produce particles at the high energies suggested by superstrings. The theory
has not made contact with the real world of the experimental physicist,
but it is still occupying most of the best theorists in the world.
The overriding problem is that much of contempo-rary theory is untestable.
The sensible conclusion to draw from the current state of physics is to
recognise that much of what is called theoretical physics is in fact interesting
and highly sophisticated mathematics, not really physics at all.
The problems begin to mount when speculation is not even acknowledged as
speculation. Morris rightly believes that 'when scientists speculate about
ideas that have not been tested, which may not even be testable, they should
be willing to admit that the activity in which they are engaging is not
quite as "scientific" as some of them would have us think' (p70).
In our speculative times, achieving mathematical beauty is widely taken
to be the guiding spirit behind physical research. In the twentieth century,
the quest for beauty has increasingly become the goal of the leading branches
of theoretical physics.
The appeal to aesthetic criteria is part of the phy-sicists' unshakeable
belief in the underlying simplicity and beauty of nature. It is one of their
most powerful guiding principles. Nature should not be more complicated
than it has to be, they tell themselves. It is this belief that motivates
the search for a 'theory of everything'.
The proponents of superstrings justify their creation by pointing to its
elegance, coherence and beauty, because as Michael Green says, 'at the moment
there are no firm predictions that we know about' (Superstrings,
p134). Nobel laureate Abdus Salam, a supporter of superstrings, nevertheless
believes that 'no theory should be believed in beyond what one can test'
(Superstrings, p170). Despite this, Salam thinks that 'the theory
is exciting because of its intrinsic merits' (p171).
Sheldon Glashow, a Nobel laureate remains unconvinced: 'Some of them are
convinced in the uniqueness and beauty, and therefore truth, of their theory,
and since it is unique and true it obviously includes a description of the
entire physical world. It does not seem to them to be necessary to do any
experiments to prove such a self-evident truth, so they begin to attack
the value of experiments from this end - a highly theoretical, abstract,
mathematical end.' (Superstrings, p182) Glashow's view was supported
by Richard Feynman, who before his death made his feelings known: 'I don't
like that they're not calculating anything. I don't like that they don't
check their ideas. I don't like that for anything that disagrees with an
experiment, they cook up an explanation - a fix-up to say, "Well, it
still might be true".'(p194)
The quest for beauty in science has a long history. But back in the Renaissance
and the Enlightenment periods, this tendency was kept in check by the prevailing
strength of experimental philosophy. It is this check that has been removed
today. For example, in the 1600s the astronomer Johannes Kepler developed
a model of the solar system as the most beautiful geometric construction
he could envisage. But he abandoned his aesthetically delightful model in
favour of his famous if rather prosaic laws which accurately reflect the
elliptical orbits of the planets around the sun. In the age of the scientific
revolution, empirical study and experimentation, not metaphysical speculation,
were the key to theoretical advance.
In the twentieth century the quest for beauty is back with us, and threatening
to take precedence over empirical and experimental study. Theoretical physics
has massively outstripped technology, as the pace of progress has slowed
since the turn of the century. The stagnant capitalism of the twentieth
century puts physical limits upon scientific development, by slowing the
rate of investment in new technologies. The decision not to proceed with
the Superconducting Super Collider is an example. Consequently a gap has
opened up between scientific theory and practice in the twentieth century
which was unimaginable in Kepler's time.
The less confident times in which we live have also given greater force
to mystical ideas, as even the idea of experimentation is in abeyance. It
was bound to be the case that there would be a growth of speculation as
the gap between theoretical physics and technology grew. But it was by no
means certain that this gap would be filled by the quest for beauty. It
is the wider ideological appeal of metaphysics in modern capitalist society
that has consolidated speculation as a positive virtue. In this context
beauty in framing theory becomes more than an heuristic device, and assumes
the character of a guiding principle.
The similarity between the religious impulse and the thinking behind much
of theoretical physics today has led some to suggest that science and religion
do compete - but only as alternative religions. Is this fair comment? One
man who thinks not is Steven Weinberg, an avowed atheist who believes that
the quest for beauty is a perfectly rational enterprise.
At a meeting of the Royal Society a few years ago, Weinberg focused on the
impasse between theory and experiment: 'physics in general is moving into
an era where the fundamental questions can no longer be illuminated by conceivable
experiments. It's a very disquieting position to be in.'
Never one to shirk a challenge, Weinberg has struck out in two directions:
to push for the SSC, and to narrow down the search for the ultimate theory
of nature using the quest for beauty as guide. His book, Dreams of a
Final Theory, seeks to get support for the SSC by explaining the attractions
of an ultimate theory of nature.
Weinberg's assumption is that there are a finite number of fundamental laws
of nature, and that these must in some sense fit together. In other words,
he believes natural law has simplicity, and an inevitability:
a simplicity in that the number of laws is finite; an inevitability in that
the nature of one law must relate to the whole, and be constrained by the
nature of other laws. These two criteria are then taken to define beauty:
'The kind of beauty that we find in physical theories is of a very limited
sort. It is, as far as I have been able to capture it in words, the beauty
of simplicity and inevitability - the beauty of perfect structure, the beauty
of everything fitting together, of nothing being changeable, of logical
rigidity.' (p119)
Both simplicity and inevitability can be captured by principles of symmetry,
which is why such a principle is popular with particle physicists. Weinberg's
assumption then is that if we find that our theories of nature possess this
beauty, we must be on the right track to finding the ultimate theories of
nature: 'It seems that we are learning how to anticipate the beauty of nature
at its most fundamental level. Nothing could be more encouraging that we
are actually moving towards the discovery of nature's final laws.' (p71)
What makes Weinberg a pleasure to read is that at least he expresses some
optimism about the possibility of expanding our knowledge. There are some
important weaknesses in his argument though, and some dangers for science
as a rational exercise.
The rather circular nature of his basic thesis - nature is simple and interconnected,
beauty is simplicity and inevitability, therefore beauty is a guide to nature's
laws - suggests that Weinberg's approach is not as rational as he might like
to claim. It is based on nothing more than a belief that nature is ordered
in a particular way. The consequence of this is that while Weinberg may
be a materialist, his approach smacks of the idealism of the ancient philosopher
Plato, who took beauty as the guide to understand the world.
Weinberg chases beauty with the best of them: 'Plato and the neo-Platonists
taught that the beauty we see in nature is a reflection of the beauty of
the ultimate, the nous. For us, too, the beauty of present theories
is an anticipation, a premonition, of the beauty of the final theory. And
in any case, we would not accept any theory as final unless it were beautiful.'
(p131) If this is not a substitute religion, what is it?
Weinberg's approach might make sense if there was significant evidence that
the mathematical laws he is using capture something fundamental about the
nature of physical reality. But there is precious little evidence of this.
In fact he admits to fiddling things to get the desired 'beauty': 'Our principles
are often invented as we go along, sometimes precisely because they lead
to the kind of rigidity we hope for.' (p120)
The elevation of aesthetic criteria over experimental is possible because
the theories are so flexible, so far removed from experimental verification,
that a wide range of them could fit the data. Which one you choose then
becomes a matter of taste, informed by whatever your sense of 'beauty' happens
to be. In this context taking any sense of aesthetics as a guide is a hazardous
business - if we want to defend the idea that science is a rational process.
In the past, experiments played a vital role in developing theory. Today,
experiments in some fields are barely managing to test out theories developed
a decade or more ago. Wherever experimental evidence can be coaxed out of
nature, it suffices to corroborate or refute a theory and serves as the
sole arbiter of validity. But where evidence is sparse or absent, other
criteria, including aesthetic ones, have been allowed to come into play - both
in formulating a theory and evaluating it.
One area where experiments could have filled in some of the gaps in our
knowledge is the notional Higgs particle. The discovery of the Higgs particle
would confirm the theory of how particles acquire the masses that they do.
The SSC was to have led the hunt for the Higgs particle or as Lederman calls
it 'The God Particle'.
Last summer, government minister William Waldegrave issued a challenge to
physicists to explain the importance of the Higgs particle on a single sheet
of paper. He wanted to understand its significance before deciding whether
or not to allocate funds to CERN for its search. Simply, the standard model
of particle physics does not work without it. The Higgs particle is needed
to make the standard model mathematically consistent. Investment in the
new generation of particle accelerators is needed if physicists are even
to know if they are heading in the right direction.
In the absence of the investment and technological advances, such as CERN
and SSC, that could go some way to giving theoretical physics a material
content, speculation abounds. Speculation is a necessary part of any science,
as a first step. The danger of the quest for beauty in science is that it
makes a virtue of necessity and arrests our thinking at the level of metaphysics.
As Morris warns, 'only confusion will result if metaphysics is allowed to
masquerade as science' (p70).
- Martyr's Day: A Chronicle of a Small War,
Michael Kelly, Macmillan, £16.99 hbk
On the Jordanian border at the close of the Gulf War a truck load of Indians,
Sudanese, Iranians, Filipinos and Egyptians were trying to get out of Iraq
and go home. Four Sudanese had died on the way of exposure. A woman was
crying in the van. The Western journalists who came across them wrote up
her story - she was crying for joy at leaving Iraq.
Michael Kelly, one journalist who looked closer, explains their mistake:
'She was crying because the baby in her lap was dead.' Kelly's personal
record of covering the Gulf War describes how journalists reported what
they expected to see rather than what was there.
Most war journalists got their information through the Joint Information
Bureau (JIB) which controlled the CENTCOM media pool system from the International
Hotel in Dhahran. The pool system on the second floor of the hotel comprised
TV sets receiving the US Forces Television Services Network together with
binders of reports from journalists on the ground - filed in the presence
of US troops. The system was set up by the US Central Command after six
months of meetings with American media chiefs.
'Coordinators' chose journalists for assignment to various military units.
The pool journalists were accompanied by Public Affairs Escort Officers
and subject to Department of Defence Rules and orders. Their reports were
sent back to Dhahran by military carrier, censored by the JIB and then became
the common material of all members of the pool.
Michael Kelly's Chronicle of a Small War is the outcome of his attempts
to get round the system of on-the-spot censorship that hamstrung his colleagues.
Kelly travelled through Iraq, Jordan, Israel, Saudi Arabia and Kuwait before
going on to Iraqi Kurdistan to get his story. Acting outside of the official
stranglehold on the media, his record of the Gulf War tells the stories
that his colleagues were blind to.
Reporting from Iraq, Kelly sees things that do not fit the official Western
view of the war as arising out of Iraqi might. He describes how in January
1991 Iraqi troops recalled to their units on the front line were forced
to commandeer any transport available. Kelly asks 'what happens in a war
in which one side has the power to move half a million troops halfway across
the world and the other has to steal buses and taxi-cabs to move a few thousand
soldiers a couple of hundred miles?'.
On the way to Kuwait City, Kelly sees a group of Iraqi soldiers waving a
surrender flag (made of a white t-shirt on a bamboo stick): 'They had no
rifles. It occurred to me as I noticed this that I hadn't seen a single
Iraqi soldier carrying a rifle since the war began.' Kelly's suspicions
about Iraq's readiness to fight were confirmed by Captain Mike Ettore of
the US marines. 'You want to know the truth about the Iraqis? They were
an inferior enemy. Pathetic.' Ettore's regiment had just killed 'in a modest
estimate' 300 pathetic Iraqis.
On the Basra Road, site of the most sustained slaughter of Iraqi troops
as they retreated from Kuwait, Kelly comes across Major Bob Nugent investigating
the debris. Nugent has found a slide-rule used by Iraqi gunners to calculate
their trajectories. 'Imagine an army using slide-rules up against an army
using computers and AWACS. Incredible', says Nugent.
Kelly's record is impressionistic and does not pretend to explain what was
behind the Gulf War. But he does prise open the stranglehold the US forces
had over reporting of the war. In doing that he illustrates a simple truth.
The real menace to the region came from the half a million troops organised
in Operation Desert Storm, not from a country that sent its troops into
battle by taxi, unarmed and with little more than a slide-rule for information
technology.
Jude Edwards
- Morality, Bernard Williams, Canto
£4.95 pbk
Go to any upmarket bookshop, look at the section on ethics and you can almost
see it expand before your eyes. Morality is in. Bernard Williams' little
book, republished here by Canto, was for many years one of the few works
on the subject. Williams indicates why in this well-argued outline of moral
theory. Until recently morality was something that was assumed, not argued
about. What views there were on the subject were either hostile, such as
amoralism - Williams' first target - or non-committal, what Williams calls
subjectivism, the idea that one set of morals is as valid as any other.
In so far as there has been an agreed morality, Williams says that it has
been that of utilitarianism, the idea that whatever leads to the greatest
good of the greatest number is moral. Morality makes a good case
that utilitarianism is too empty to provide a real basis for agreement over
right and wrong. Marx ridiculed it as the mental arithmetic of the businessman,
balancing right and wrong against profit and loss.
Williams' quest for an alternative, however, is no more substantial than
utilitarianism. He cites Martin Luther's rejection of the idea that the
quest for happiness should be the basis of what is good. Not happiness,
says Luther, the founder of Protestantism, but 'suffering and the cross'
is the basis of what is good. Sensing that a modern readership would balk
at crucifixion, Williams recommends a formula from the novelist DH Lawrence:
'Find your deepest impulse and follow that.' This Lawrentian argument is
a celebration of intuition, that says that it is better not to think about
morality, but do what you feel to be right.
In Lawrence's morality we are still to be driven by forces beyond our understanding,
and, as with Luther, these forces come from within. An intuitive personal
morality can work as long as individuals spontaneously adopt goals that
can be reconciled with the status quo. The deepest impulse of the mountaineer
is easier to applaud than the deepest impulse of the bank robber.
But the current interest in ethics is precisely that moral intuition no
longer appears to be a sufficient guarantor of social order. In simple terms,
the bank-robbers outnumber the mountaineers. In these circumstances we can
expect to see more attempts to impose moral probity from the outside - from
debt-counselling to job-seekers contracts - and less respect for individual
conscience.
James Heartfield
Reproduced from Living Marxism issue 63, January 1994
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