Letter: Green demise
Your suggestion that the Green Party in Germany contributed somehow
to the changes in Eastern Europe is absurd (Comment, 8 December). Their
attitude towards communism has been ambivalent, to say the least. They have
opposed German unification all the way since the fall of the Berlin Wall
right up until the elections last month. Instead, they have issued high-handed
directives to the long-suffering East German people to eschew Western living
standards (which they themselves take for granted). They earned nothing
less than the scorn they deserved by being shunned by voters in the first
all-German election.
A Green party in power would certainly not be the Utopia you suggest.
Environmentalism – a worthy issue – is not the point. The Greens represent
a pseudo-romantic, anti-intellectual stream of thought which has a long
tradition. To them, ‘chemical’ is a dirty word, only recently having been
replaced by ‘genetic engineering’ as public enemy number one. Here in the
state of Hesse, where the Greens have some share in local government, they
have successfully deprived the public of facilities to make genetically
engineered pharmaceuticals, including insulin and erythropoietin.
Stephen de Looze Wiesbaden Germany
Letter: Age of steam
I note with interest the ‘air-driven train’ installed in Jakarta (Technology,
24 November). While this method of propulsion may have been refined by the
Brazilian company mentioned in the article, it is certainly not new. The
South Devon Railway, a broad gauge line running west from Exeter towards
Plymouth, employed exactly the same method over 100 years ago.
Developed by Isambard Kingdom Brunel, the ‘atmospheric railway’, as
he called it, used a cast-iron tube mounted inside the running rails, with
a leather flap running along the inside of a slot in the top to seal it.
Engines, pumping steam, were installed every few miles to provide positive
air pressure in the pipe, which acted on a piston suspended beneath the
train, causing the train to move with no visible means of locomotion.
Unfortunately, the leather flap was the downfall of the system – with
the technology of the day it proved impossible to obtain a sufficiently
airtight seal. This little known experiment, which covered over 15 miles
of track, was discontinued in the last half of the 19th century. One of
the original pumping engine houses, at Starcross near Dawlish, is now a
museum dedicated to Brunel’s invention.
Martin Pyke Auckland New Zealand
Letter: Water improvements
Your editorial on water regulation does not take us very much further
forward (8 December). What are these ‘crystal clear and urgent needs’ that
are not already included in the 28 billion Pounds programmes for the next
10 years and the new EC waste water directive, which is imminent?
The water service companies are not mounting a whispering campaign against
Lord Crickhowell, or anyone else. Instead, they are shouting as loudly as
they can to all who will listen: for the immediate and urgent requirements
are to achieve the current 28 billion Pounds programme and the additional
programmes which will follow on the waste water directive. If there are
yet more desirable improvements then these need to be specified exactly
and costed, and government on behalf of the community should then say whether
they should be pursued and by when.
To achieve standards in the water environment, instead of merely promising
them or talking about them, is what is now required. We should concentrate
on making sure that they are achieved. Accordingly, the WSCs will implement
the major 28 billion Pounds programmes of improvement and the EC waste water
directive, which will have the most significant impact on the water environment.
It is earnestly hoped that they will not be diverted from this immense task
by vague, unspecified and unquantified generalisations about having something
even better.
Michael Carney Secretary, Water Services Association London
Letter: Wholesome food
In regard to Simon Pugh’s response to my letter (1 December), I feel
it necessary to clarify the position of wholefood enthusiasts. I am well
aware and in full agreement that ‘life is chemistry’. Yes, many natural
components in natural foods are toxic. But that does not justify the additional
indiscriminate use in our foods of any substances the chemist can concoct
in his or her laboratory. One must know the issues and weigh up the risks
.. for example, do I need to increase further my risk of poisoning by ingesting
coal tar food dyes, which are chemicals found nowhere in the natural environment?
There is no distress, as suggested by Pugh, in making the choice to avoid
them.
But the issue runs deeper than simply the safety of food additives.
In general, the more chemical additives a food has, the more it has been
processed, the less nutritious it is, and the higher its content of compensating
flavour-enhancing fats and sodium. Hopefully, there is no argument as to
the risks involved in too high a consumption of these ‘chemicals’.
Furthermore, I wish the chemists would show consistency in their approach.
One minute they tell us that certain chemical products are toxic and next
they call us worriers because of a convoluted belief that nutrition and
health is simply a branch of chemistry.
In my work as a biologist, I have had the opportunity to work with a
fungicide so hazardous that one must handle it under a flow cabinet wearing
mask and gloves. This fungicide is sprayed on crops and then eaten by the
public. If the additives community believes this too to be a ‘worriers’
issue, I’ll be happy to send along samples of these fungicides for them
to add to their recipes.
Richard Weinstein Slough Berkshire
Letter: Kick down
Having myself given up caffeine with beneficial effects on my blood
pressure, I wonder whether the reasons for people switching to decaffeinated
coffee were taken into account in the Stanford and Harvard studies (‘Anyone
for designer coffee’, 22/29 December). In other words, did they change because
they already had a cardiovascular problem?
John Brunner South Petherton Somerset
Letter: Antarctic protection
I was disheartened to read Debora MacKenzie’s report of the Antarctic
Treaty meeting in Chile (This Week, 15 December). Anyone with a real understanding
of the issues would have been heartened by the progress made at Vina del
Mar. The talks were about proposals for the comprehensive protection of
the environment, not about mining.
Most of the parties at the conference were concerned with the impacts
that exist on the Antarctic today – mainly scientific research, logistics
and, to a lesser extent, tourism – not with the potential effects of mining,
which are unlikely to occur within the next few decades in any case.
Progress was good on practical issues. Documents were agreed on the
prevention of marine pollution, waste disposal and waste management, protection
of fauna and flora and, very importantly, on environmental impact assessment.
All these topics, previously covered by measures under the Antarctic Treaty,
have now been equipped with enhanced safeguards that will lead to a degree
of protection unequalled over any comparable area of the world.
This is no mean achievement. The precise legal form of the final instrument,
the main issue awaiting agreement, is less important. It is true that there
is a need to reach agreement over mineral activities. The supporters of
mining are Japan and South Korea. The British position, as I understand
it, is that the appropriate safeguards are provided by the Convention for
the Regulation of Antarctic Mineral Resource Activities, and that this would
provide better protection than a simple ban.
Niger Bonner Huntingdon
Letter: Exhaust stroke
While we should welcome the government initiative to introduce vehicle
emission testing into the MoT, the Department of Transport’s current proposals
for testing are wholly inadequate (This Week, 15 December). The proposed
emission standard of 4.5 per cent carbon monoxide is so lax that many cars
which perform badly will still pass the test, continuing to cause pollution
and waste energy.
New cars should only produce 1 to 3 per cent carbon monoxide at idle,
and all modern cars should be capable of tuning to produce 3 to 4 per cent.
The Department of Transport consulted a range of organisations on their
proposed standard of 4.5 per cent. Many argued for a tighter standard but
the department stuck to its original proposal, which it described as ‘sufficiently
generous to allow for all but very badly performing engines’. Is it therefore
the department’s intention to allow badly performing engines to escape detection?
An alternative approach would see MoT emission standards based on individual
manufacturers’ specifications rather than an overall ceiling figure at which
most cars would already be performing very badly indeed.
Tim Brown National Society for Clean Air Brighton Sussex
Letter: Travelling light
Mike Barker asks about spaceship acceleration times (Letters, 15 December).
If we take the acceleration as 20 g (being the most the human body can sensibly
stand), then it would take around 17 days to reach just below the speed
of light, travelling 2.3 x 10 11 kilometres in the process (around
40 times the distance from the Earth to Pluto). This acceleration would,
however, be very uncomfortable and it is extremely unlikely that it could
be sustained for 17 days.
A better idea is to accelerate at 1 g, thus simulating Earth gravity.
The figures then become approximately 1 year and 4.5 x 10 12
kilmetres (half a light year). These figures must be doubled if deceleration
is included. Clearly, near-light-speed travel is not an option within the
Solar System (though it is ideal for interstellar travel) unless some sort
of artificial gravity system can be arranged to protect the crew from the
effects of acceleration.
Tony Cains Stockton-on-Tees Cleveland
Letter: Saving free will
I liked John Gribbin’s tribute to John Bell (‘The man who proved Einstein
was wrong’, 24 November). I was particularly pleased to see that, unlike
many commentators, Gribbin notes that Bell pointed out that we can avoid
faster than light nonlocal connections, so long as we are prepared to concede
that the present state of a physical system may depend on what happens to
it in the future. But as Gribbin says, Bell saw this possibility as incompatible
with free will. On balance, he therefore regarded it as even more unsatisfactory
than nonlocality (despite the latter’s conflict with the conceptual framework
of special relativity).
However, Bell seems to have failed to recognise that there is an alternative
way to interpret the idea that present states depend on future states, an
interpretation which saves free will. This is to admit an element of backward
causation, saying that when the experimenter (freely) chooses a particular
setting of the measurement apparatus, he or she thereby affects the past
state of the incoming particle. The usual worry about backward causation
is that it leads to causal loops, and hence to the sort of inconsistencies
involved in the famous paradoxes of time travel (auto-infanticide and the
like). But these problems cannot arise in the present case. (The easiest
way to see this is to note that if the backward causation interpretation
did lead to such mathematical inconsistencies, so too would Bell’s own ‘no
free will’ interpretation, for the mathematics is the same.)
Why did Bell fail to appreciate this possibility? Apparently, because
he was convinced by the argument that if it is already true that an incoming
particle has the state which would result from its being subject to (say)
a spin measurement in the X direction, then we cannot really be free to
choose whether to make that measurement rather than another one. However,
except for the fact that the claimed result of our choice lies in the past,
this line of reasoning is exactly parallel to an ancient argument for fatalism,
namely that if it is already true that there will be a sea battle tomorrow,
then we mortals have no choice or influence in the matter. Admittedly, this
kind of argument has sometimes been very influential, but few contemporary
philosophers or physicists would take it seriously. It is odd that it seems
so much more convincing when the effect of choice lies in the past rather
than the future.
The difference reflects the fact that the belief that we cannot influence
the past is very deeply rooted in our intuitive conception of the world.
It is much more deeply entrenched than the principle that action should
be local, let alone the comparatively novel framework of special relativity.
And no doubt this explains why the backward causation interpretation has
usually simply been disregarded by the physicists and philosophers who have
puzzled about quantum mechanics. But it is surely time to ask whether we
have our priorities right. If the worst that can be said against backward
causation is that it offends deep seated intuitions, and yet it saves special
relativity, then isn’t it the intuitions that should go?
So was Bell the man who proved Einstein wrong? Perhaps, but I suspect
not. I think that history’s judgment will be that he was a man who saw how
Einstein could be right, both about the incompleteness of quantum mechanics
and the relativity of simultaneity – but a man who tripped on an old philosophical
hazard, and so was unable to believe what he saw.
Huw Price University of Sydney Australia