Letters: Endless maths
William Bown, in ‘This is the way the maths will end’ (Forum, 14 September)
says: ‘All the physics lies in writing down the right equation in the first
place. Solving it is just a technicality.’
Some 60 years ago, Herman Glauert, the aerodynamicist, said to me (then
a laboratory assistant): ‘Fairthorne, one day people will bring you differential
equations to solve. Don’t start on this before finding out the physical
problem involved. Nine cases out of ten, the differential equation doesn’t
arise.’ The years since have served only to widen the validity of his remark.
An even older adage, dating from my boyhood, is: ‘In mathematics you
must always know the answer first.’ In more practical terms: ‘Never use
a calculating device, from slide rule to Cray, without having a rough idea
of what you suppose the result to be.’
R. A. Fairthorne Farnborough, Hampshire
Letters: Plague on your plug
Who designed the modern telephone plug?
It is not safe: it ‘locks’ into the socket, when it should only ‘click’
so that it will pull out if anyone trips on the wire. It is not durable:
the catch is easily broken off. It is not fail-safe: depending on where
the catch breaks, it either falls out too easily, or it locks in permanently.
It is not economical: if it breaks it cannot be replaced without specialist
tools, so the whole cable, if not the equipment itself, must be replaced.
It is not ergonomic: with its ‘barb’, untangling wires is like extracting
a fish-hook from a ball of wool.
There should be a special industrial design award for such incompetence!
J. C. Stopes-Roe London
Letters: Cactus rustlers
It has become trendy in the South Western United States to replace water-thirsty
gardens with xeriscapes (‘Squeezing the deserts dry’, 14 September). Unfortunately
this has spawned the new crime of cactus rustling, which is having severe
consequences on the desert plants of California, Arizona and Texas.
Large cacti take many years to mature and, like many wild plants, transplant
badly. Mature specimens fetch high prices and usually do not look dead until
some time after they are sold by unscrupulous dealers to unsuspecting buyers.
Special anti-cactus rustling squads have been set up, but since state
and national parks cover such wide areas, it is very difficult to prevent
the increasing threat to the desert landscape.
Pamela Manfield Swavesey, Cambridgeshire
Letters: Fixing flatulence
Re ‘Greenhouse fixes’ (Letters, 21 September), indigestion tablets fed
periodically to commercial cattle would reduce the incidence of flatulence.
This would reduce the amount of methane released and therefore help reduce
global warming. In addition the standard of social life of the average cow
would be significantly improved.
M. Sephton St Helens Merseyside
Letters: Bum's rush
It was recently reported that a correspondent to a cycling magazine
has recommended placing a peeled banana between the cheeks of one’s buttocks
as a way of reducing saddle-soreness. Apparently, the banana mushes up during
the ride and lubricates the affected parts. Have the Dutch tried this?
C. Quinn Liverpool
Letters: Bum's rush
I was very interested to read about the Dutch efforts to develop a better
bicycle saddle (This Week, 21 September). As a racing cyclist, I would certainly
agree that saddle soreness is a very common problem.
This is because all racing cyclists sometimes find themselves perched
‘on the rivet’. During the intensity of races, a cyclist under extreme pressure
will inadvertently slide forward on the seat until balanced on the sharp
pointed bit at the front of the saddle, thus putting much of the body’s
weight on an area no more than a few square centimetres – a bit like sitting
on a spade handle. The pain and damage this can cause is never noticed until
the end of a race.
The symptoms in men can be far worse than those described. Inability
to urinate and prostatitis are not uncommon and I have heard of temporary
impotence.
Rick Gould Lancaster
Letters: Cornflake cover-up
You state (Letters, 28 September) that as Jonathan Heywood’s alleged
Mandelbrot cornflake got squashed in the post, you were unable to analyse
its geometry. But if it is a Mandelbrot cornflake then its boundary (at
least) will be self-similar at all scales, so you would be able to recover
the shape of the whole from the smallest crumb. In fact, Jonathan Heywood
states this (by implication) quite clearly, and I suspect a cover-up. Tam
Dalyell should look into this.
Colin Bartlett Bournemouth, Dorset
Letters: Multiple answers
The answers to S. P. Kingsley’s question ‘Why aren’t sheep green?’ (Letters,
14 September), should be compulsory study on every science course, as they
illustrate almost every type of answer that it is possible to give to a
scientific question!
There is the textbook Darwinist interpretation which doesn’t look too
deeply into special conditions (‘evolution works like this’), the realist
or causative answer (‘sheep are bred this way for a purpose’), the ecological
niche argument (‘green things are green because . . . ‘), the reference
to other fields of study, the frivolous answer, the humorous quip with political
overtones and, last but not least, an example of lateral thinking that questions
the validity of the assumptions.
We seem to be missing the religious answer (‘God made sheep white’)
and its modern equivalent the philosophical answer (‘the Theory of Everything
says green sheep are impossible’), the climatic change theory (‘green sheep
became extinct 10 million years ago’), the anti-industrial theory (‘environmental
pollution killed them all’) and its cousin the cultural impact study (‘Spanish
sailors killed the last one in Madagascar in 1763′) and, of course, the
conspiracy theory (‘blame the CIA /the KGB/ aliens’).
These arguments illustrate the extent to which our understanding of
nature depends on the type of explanations we seek, a point which is not
often stressed but is nonetheless fundamental to the nature of scientific
enquiry. Perhaps every student should be required to give examples of each
type of answer to some suitably simple question!
A. M. New Bristol
Letters: Energy thrift
You report Frank Dobson as saying the Department of Energy increased
its energy consumption by 60 per cent over the last year, and that this
calls into question the government’s commitment to energy conservation (In
Brief, 28 September).
Dobson has fallen into the trap of not comparing like with like. My
department only moved into its present headquarters building in August 1989
and consequently its energy consumption figures for 1989/90 cover only some
seven months of that year. As that building accounts for around 80 per cent
of the department’s total energy consumption it is hardly surprising Mr
Dobson comes up with such a high figure when comparing a seven-month period
with a full year.
My department is fully committed to achieving the government’s target
of 15 per cent energy savings on the central government estate over the
next five years.
David Heathcoat-Amory MP Department of Energy London
Letters: Rings and things
In the story ‘Global warming rings true’, it is suggested that the thicker
tree rings observed during recent years may indicate global warming (New
杏吧原创, Science, 21 September). This may be so. But it appears to me
that it could also be because of the fertilising effect of acid rain and
the increase in atmospheric carbon dioxide during recent years. Plants grow
faster these days owing to acid rain and the higher content of CO2
in the atmosphere.
Ivar Aanderaa Bergen Norway
Letters: Prize statistic
I should like to propose Clark Chapman of the Planetary Science Institute
in Tucson, Arizona, (‘Will we catch a falling star?’, 7 September) for the
Royal Statistical Society’s prize for ‘outstanding original contributions
to statistical theory or application’ (Feedback, same issue) for his estimation
that ‘people alive today have a 1 in 6000 risk of dying from an (asteroid)
impact, three times the risk of dying in a plane crash’ (1 in 20 000). I
wonder what effect these statistics will have on life insurance premiums.
Steve Turner ICI Chemicals and Polymers Middlesbrough, Cleveland
Letters: Virtual matter
In regard to your article ‘Energy of ‘nothing’ upsets cosmology’ (New
杏吧原创, Science, 31 August), I was troubled by what seems to me to be
an anomaly. On the one hand, we have the zero point field supposedly causing
an excess of gravity, while on the other hand we have scientists looking
for ‘cold dark matter’ to explain the gravity we already have. My question
is, why can’t the one be the explanation for the other? Why can’t the cold
dark matter be virtual particles? Could someone please explain?
R. van Spaandonk Bacchus Marsh, Victoria Australia
Letters: Going for gold
Catching up with my post-holiday reading, I was struck by a sentence
in the opening paragraph of ‘The successful alchemist’ (10 August): ‘The
medieval alchemists sought the conversion of base metals to gold as a fundamental
research objective, albeit one that it is difficult for people brought up
on the atomic theory of matter to understand.’
What is the difficulty? The alchemists were empirical scientists. For
centuries base metal – namely copper – had been ‘transmuted’ to different
metals with quite different characteristics of hardness, strength and colour,
by adding various types of ‘stone’ to it. They added black/brown cassiterite
(tinstone) to copper melts to produce bronze; they invented cementation
by heating granulated copper and the white stone-like zinc mineral smithsonite
with charcoal in sealed crucibles to produce brass. Bronze and brass were
more gold-like than copper; what could be more natural than to suppose that
by adding the right stone to the right metal in the right way they would
get gold?
Atomic theory may show that the alchemists were badly led astray, but
to medieval science their investigations were entirely logical. Need we
be so smug? Does our research never lead us up the garden path?
John Barnes Swansea, Wales
Letters: Gleaming eye
You reported the chairman of SERC’s enthusiasm for upgrading ISIS, the
spallation neutron source at the Rutherford Appleton Laboratory, to become
the European neutron source of the future (This Week, 28 September).
Over the last year, nuclear physicists in Britain have not always seen
eye-to-eye with SERC’s chairman: on this subject, however, they are right
behind him, since ISIS can simultaneously be a major facility for nuclear
physics as well as Europe’s premier neutron source.
One can only echo Sir Mark Richmond’s criticism of the Treasury’s reluctance
to help to obtain international centres in Britain. Switzerland obtains
a 600 per cent return on its subscription to CERN from orders placed with
industry. On top of this, CERN salaries are spent in Switzerland. Only someone
involved with the British economy would see this kind of return as not worthwhile.
Two years ago, British nuclear physicists identified a radioactive beam
facility based on ISIS as their future home when the Nuclear Structure Facility
was slated to close in 1997/98. The precipitate closure of the NSF has made
it hard to sustain the excellence of British nuclear physics in the medium
term but the gleam in Sir Mark’s eye may be bright enough to light the way
ahead for nuclear physics too. All it needs is a healthy nuclear physics
research community and a more enlightened Treasury.
William Gelletly Nuclear Structure Facility Daresbury, Cheshire
Letters: Time is energy
The experiments illustrated in ‘A special theory of relativity’ were
conducted on the Dutch railway, to judge from the emblem on one of the coaches.
Is this because the time dilation associated with British Rail is too
extreme for even Einstein to accommodate?
David Hill London
Letters: Time is energy
One question about general relativity/time dilation has intrigued me
for 50 years but my mathematics is inadequate to answer it (‘A special theory
of relativity’, Inside Science, 21 September).
When a body is accelerated to near the speed of light and then its direction
of travel is reversed and it returns to whence it came it has aged less
than companion bodies that have remained stationary. This process, of course,
requires energy. How much? How many joules are needed to make 1 kilogram
of matter one second less old? Does growing old create energy?
P. Marchese Maidstone, Kent
Letters: Grading standards
While supporting Fullick and Fullick’s call for reform in science education
for 16 to 19-year-olds (Talking Point, 31 August), I object to the implication
that the present grading system compares candidates with one another rather
than against a set of agreed performance criteria. A grading system based
on predetermined percentages achieving the various grades ceased to exist
in 1987. The E/N (pass/fail) and other grade boundaries are based on close
scrutiny of candidates’ scripts by a panel of experienced examiners (including
A-level teachers) who agree on the minimum standard required for the award
of each grade. No candidate is condemned to failure merely as a result of
being in the lower tail of the distribution.
Lynn Burnet King Edward VII School Sheffield, South Yorkshire
Letters: Nuclear arms cuts
If President Bush’s proposals on nuclear arms cuts are put into effect
and meet a like response from the Soviet Union, but no further cuts are
made, the exercise will have been pointless. This has to be the thin edge
of the wedge.
This is recognised widely, but especially by those people with a stake
in military and related activities. We are now seeing a strong reaction
from the military lobby against recently proposed British military cuts.
About half of the world’s scientists and engineers are said to be employed
in military and related work. Herbert York and Solly Zuckerman have explained,
from direct knowledge, how effectively senior nuclear weapons scientists
and technologists can lobby for their institutions.
The arms cuts initiatives of Presidents Bush and Gorbachev must, if
they are to be effective in the long run, be linked with conversion plans.
The funds are available from military savings.
A large part of the ‘peace dividend’ should be earmarked for education,
training and investment in alternative employment for scientists, engineers
and all other workers in military and related spheres. Such a programme
should provide constructive opportunities not only for those now in military
and related work, but also for young people seeking their first full-time
employment.
Alan Cottey 杏吧原创s Against Nuclear Arms London
Letters: Dainty rhino
I was captivated by the illustration of a ‘slender rhinoceros’ (‘Time
to save rhinoceroses’, 28 September). I’m sure most overweight people would
be glad to be described so if they had that rhinoceros’s figure.
Alec Vans Newnham, Gloucestershire