Letters : . . . . .
The fallacy lies in equating the year 2000 with the 2000th year. They are not
one and the same. The 2000th year is not the year 2000, it is the year 1999.
If we take the start of our calendar as being 1 January 0000, the debates
over the actual year of the birth of Christ and the changes in the calendars
being another matter, the first year passed on 1 January 0001. The second year
passed on 1 January 0002 and so on.
So the year 1998 indicates 1998 years completed, and we are now in the 1999th
year. The 2000th year is, therefore, the year 1999, and the new millennium
begins on 1 January 2000鈥� the 2001st year.
As a further guide, one might ask oneself why we are currently in the 20th
century although the year is 1998. “20th century” means we have completed 19
centuries, and we are partly through the 20th. By the end of this century, we
will have completed 20 centuries, and we will therefore have completed two
millennia and will have arrived in the 21st century.
We should not lend weight to an argument that is clearly flawed, even if an
Astronomer Royal made the same mistake almost a century ago.
Letters : The real millennium
Arthur.Chance@Smallworld.co.uk
There are two good arguments why the new millennium should be celebrated at
the beginning of 2000 rather than 2001
(Feedback, 24 January). One is historical
and mathematical, the other pragmatic and alcoholic.
The historical and mathematical argument is this鈥攑eople who argue that
2001 is the beginning of the next millennium on the grounds that the calendar
started at AD 1 and AD 0 didn’t exist are being insufficiently pedantic.
It is true that AD 0 didn’t exist, but then neither did AD 1, AD 33 or AD
100. In fact, AD dates didn’t exist until the early sixth century AD, when
Dionysius Exiguus devised the Christian calendar. So the lack of historical
existence of AD 0 is not a reasonable argument to disbar 2000 as the beginning
of the next millennium, unless one is prepared to say it actually occurs in the
early 26th century.
Furthermore, Dionysius devised the calendar incorrectly. Jesus was probably
born in 7 BC, and was definitely born before 4 BC (the year Herod died). So the
forthcoming millennium really has nothing to do with the birth of Jesus or
Christianity, no matter what the bishops might hope, but is merely an arbitrary
numerical celebration, and we should turn to mathematics rather than religious
history for guidance. As everyone knows, the natural numbers start 0, 1, 2, …,
so AD 0 must exist theoretically, if not historically. Thus 1999 is the last
year of the 20th (not the 19th) century.
The pragmatic and alcoholic argument is this鈥攎any people wake up with a
hangover on New Year’s Day. If the millennium starts on 1 January 2000, which is
a Saturday, they will have Saturday, Sunday and in much of the world the holiday
Monday to recover before going back to work. (Scots get Tuesday off as
well.)
However, if the millennium starts on 1 January 2001, which is a Monday, they
will have only one day to recover. Given that the millennium celebration
hangover is liable to be far worse than the normal New Year’s Day one, three
days for recovery is a lot better than one, and 2000 is the obvious choice.
Letters : Shining too bright
Cambridge, Massachusetts
I was shocked to read the article on “tricky light”, in which I was quoted
(This Week, 17 January, p 17).
Had I been told by the interviewer that a “single” satellite (let alone 72)
will be visible from the ground with the intensity of moonlight, I’d certainly
have said that professional as well as amateur astronomy will potentially be
impacted in a very serious manner.
We are trying to correct a century of ill-informed outdoor night lighting
practice by urging the world to reduce glare and light trespass鈥攁nd to
save energy and money鈥攖hrough laws and industry policies that mandate
fully shielded lighting (full-cutoff luminaires that do not emit light above a
horizontal plane passing through the lamp) with modest amounts of lumen
output.
Nobody should have the “right” to indiscriminately light the night-time
environment in a destructive manner.
Letters : Blunt about badgers
Pewsey, Wiltshire
Your summary of the report of the Krebs committee is altogether
oversimplified
(Editorial, 10 January, p 3).
To say “We still don’t know if badgers spread tuberculosis” is only true in a
very casuistic sense. You could say in the same way that we still don’t know
whether Darwin’s theory of evolution is true, but that would be to ignore the
overwhelming weight of evidence in each case.
What Krebs said is: “The sum of evidence strongly supports the view that, in
Britain, badgers are a significant source of infection in cattle.”
The report adds that in total, the available evidence is compelling. To
summarise by saying “we really don’t know” is seriously misleading, and will
only confuse those who do not read the report or the evidence.
Letters : Living Earth?
Shoreham-by-Sea, West Sussex
Reading Fred Pearce’s review of Tyler Volk’s Gaia’s Body
(Review, 17 January, p 46),
I was somewhat amused by the comment that the book was getting
rid of some of my father’s “mumbo jumbo”.
Pearce says that Volk “is forced to jettison a lot of Lovelock’s language
about the Earth being `alive'”. Pearce then goes on to say: “Volk sees Gaia as a
`global metabolism’…a `symphony of material flows and cycles’.”
I make no claims to be a biologist, but my copy of the Dictionary of
Science and Technology defines metabolism as the “sum-total of the chemical
and physical changes constantly taking place in living matter”. Might I suggest
a rule of thumb in this tricky area: if it has a metabolism, then it is probably
alive.
Also, isn’t a symphony something that has been orchestrated by an
intelligence?
Letters : Give them a hug
Crewe, Cheshire
Michael Lewis found that mothers soothing their babies after an inoculation
did nothing to relieve their stress because “levels of cortisol in the saliva
remained unchanged after 20 minutes”
(In Brief, 24 January, p 23).
As a parent, I am convinced that soothing my children does relieve their
stress. They stop crying and become distracted much sooner than if ignored.
If Lewis thinks that the mothers’ consolation did have long-term benefits, as
he stated, these would have to be the result of the effects of short-term
benefits, otherwise what is the mechanism?
Could it be that measuring levels of salival cortisol is a poor measure of
the stress a child or animal is feeling at that time? Are there other hormones
that give a better indication of existing or immediate stress, rather than just
recent stress?
Letters : . . . . .
Vantaa, Finland
The image invoked seems to be of our rebellious free will somehow being given
an opportunity to exert itself in the gaps left by chance鈥攁 “free will of
the gaps”, rather like the God of the gaps.
Letters : Dawkins determinant
Newcastle upon Tyne
Derek Freeman defends Richard Dawkins against the charge of crude determinism
(or fatalism) by citing Dawkins’s sudden claim at the end of The Selfish
Gene that “we, that is our brains, are separate and independent enough from
our genes to rebel against them…We do so in a small way every time we use
contraception”
(Letters, 17 January, p 52).
It is not explained in what sense our brains are independent from our genes.
But the main trouble is that the first page of the book carries the claim: “We
are survival machines鈥攔obot vehicles blindly programmed to preserve the
selfish molecules known as genes.” Every subsequent page reinforces that
fatalistic message.
The machine imagery has to mean that all our acts are programmed by our
genes. And since our supposed rebellion is one of these acts, it must be pure
self-deception to suppose it is independent.
As for contraception, the book admits that many animals do not breed, but
insists that their refusal to do so is programmed by their genes to increase
gene-spread in less direct ways.
Altogether, these fatalistic claims are far too strong to be cancelled by a
deathbed repentance in the last chapter.
Letters : Cold versus carbon
Kooyong, Victoria, Australia
Fred Grisley is right in saying an ice age could start any time鈥攁ny
time in the next few thousand years, that is
(Letters, 10 January, p 49).
It will be coincidence indeed if its timing just happens to match the few
decades we are taking to dump into the atmosphere all the fossil carbon
accumulated over a million years. More probably, the ice will not arrive until
all fossil fuels are spent and natural processes have converted the resulting
carbon dioxide into carbonates鈥攗seless to our freezing descendants.
But do not despair! By then, greenhouse-induced climatic catastrophe may have
so reduced our numbers that there will be enough caves to go round.
Letters : . . . . .
Castel, Guernsey
The “real” millennium has, most likely, already happened. It seems generally
accepted that Dionysius Exiguus was mistaken in his choice of the year 753 AUC
(anno urbis conditae鈥攁fter the founding of Rome) as the date of
Christ’s birth, and it is now believed that Christ was most likely born in the
year 749 AUC (4 BC).
The 25th December became established as the date of the birth of Christ
because it was nine months after Lady Day, 25 March, the day of the
Annunciation, which itself coincided with the vernal equinox. The 1st January
was accepted as the start of the year, rather than 25 December, because it was
the Feast of Circumcision. Circumcision traditionally took place seven days
after the birth.
Thus, the epoch of our calendar should really be 1 January 3 BC, and the new
millennium started on 1 January 1998鈥攕everal weeks ago.
Letters : . . . . .
fell@email.msn.com
I hate to cross swords with those of a cantankerous disposition, but you are
mistaken in your belief that the millennium begins on 1 January 2001. Birthdays
are celebrated at the end of the year because that is when an individual is a
year older鈥攁 baby is one year old at the end of its first year.
Letters : Chocolate economy
kgould@apple.com
Your item on the apparently excessive consumption of chocolate by the Chinese
might be explained by a little lateral thinking
(Feedback, 17 January).
I was recently interested to read an article concerning the potential use of
liquid chocolate as a dynamic medium for shock absorbers. If the liquid is
subjected to a high electrical charge, it becomes much more viscous.
Perhaps it’s not being eaten but being used by the rapidly advancing Chinese
industries for innovative purposes.
Letters : Watering Mars
Ume氓, Sweden
Richard Gott states the need for a permanent, self-sustaining colony on Mars
as an insurance policy against catastrophe for the human species
(“A grim reckoning”, 15 November, p 36
and Letters, 17 January, p 51).
The keyword is “permanent”. The Earth has a thick atmosphere, active plate
tectonics and global oceans, which make the biosphere virtually self-repairing.
Unless Mars was extensively “terraformed”, a space colony would rely heavily on
an artificial, and therefore vulnerable habitat, negating the “insurance”
aspect.
Although Mars has considerable reservoirs of water, it is questionable
whether they would suffice to turn the northern lowlands into a global ocean.
But the colonists need not rely on “indigenous” water.
The discovery of the planetoid 1996TL, beyond Neptune, implies the existence
of a swarm of “scattered icy objects” estimated to have a total mass half that
of Earth鈥攎ost of it frozen water, methane and other volatiles. If a
fraction of these objects had their orbits altered to bring them near Neptune
for a gravity assist, and were aimed at Mars, they might turn it into a warm,
wet greenhouse world.
Critics may say, with justification, that stopping the deterioration of our
own biosphere is a more urgent concern for our survival than space colonies.
Drafting the carbon-dioxide lobby as Martian colonists would neatly fulfil both
objectives, especially if no return vehicles were provided.
Letters : Evidence devoured
Wareham, Dorset
Chris Osman, whose compost bin “happily” swallows up meat
(Letters, 10 January, p 51),
would be strongly supported by the late W. D. Newcombe of the
Department of Morbid Anatomy at St Mary’s Hospital Medical School, London.
In the 1940s, he would take home interesting specimens from the post-mortem
room to study and, being a keen gardener, rather than bothering to return the
remains to the department, he would dispose of them, bone and all, on his
compost heap. When a colleague commented that he might find himself in trouble
were any incriminating bits found, he asserted that his compost heap would
destroy any organic matter and that it was far more efficient than the murderer
John Haigh’s acid bath.
Letters : . . . . .
We apologise for a grave oversight. The international panel on physical
constants (CODATA) now deems the “best” value of Big G to be6.67259 卤
0.0008 脳 10-11 Nm2kg-2.
The researchers mentioned in “The legend of Big G”
found values that were many standard deviations above or below this value. The
group from Germany’s standards lab, PTB, were 42 above, and the Wuppertal and
New Zealand teams were 3.2 and 5.8 below, respectively.
杏吧原创s gnash their teeth when experimental values differ by more than one
or two standard deviations鈥擡d
Letters : . . . . .
by e-mail
David Kestenbaum’s article on G was enjoyable. But it never quoted even a
single value for G, let alone the various results of the researchers mentioned.
I can’t stand the suspense. You can tell me. What were they?
Letters : G on the spot
Oxford
The article on Big G
(“The legend of Big G”, 17 January, p 38)
states that
Henry Cavendish “pioneered” the gravitational torsion balance which he used to
measure big G in 1798.
This is not so. Cavendish inherited the apparatus from John Mitchell who died
in 1793, before he could perform the experiment himself.
Letters : Algal arithmetic
Solva, Pembrokeshire
Simple arithmetic suggests that it is a forlorn hope to use green algae to
scavenge carbon dioxide from power station flue gases
(This Week, January 17, p 20).
A modest 1000-megawatt station releases about 6 million tonnes of CO2
per year. At maximum theoretical photosynthetic efficiency and with
tropical availability of sunlight, it is not possible to fix more than about 30
tonnes of carbon per hectare each year. In practice, in temperate areas the
amount will be much less, even in clever conical bioreactors.
Six million tonnes of CO2 contain 1.6 million tonnes of carbon, so
each small power station would require over 500 square kilometres of
photosynthetic area. Britain’s average power consumption would need nearly 20
000 square kilometres, about the area of Wales.
Letters : Correction:
The third last paragraph of the Inside Science
“Mission Earth” (13 December 1997)
should have read as follows:
“Finally, energy use is a growing global problem (Figure 4). Most of our
energy needs are now derived from nonrenewable sources such as gas, coal and
nuclear fuels. Globally, annual energy use is now expressed in terawatt hours
(TWh), with 12 TWh (12 脳 109 kWh) the equivalent of burning a
million tonnes of oil.
According to BP World Energy Statistics, global energy use in 1996
was equivalent to burning 8.38 billion tonnes of oil, which is about 100 000
TWh. Of this, only 2000 TWh, or 2 per cent, came from renewable
sources鈥攕olar and wind power.
The World Energy Council estimates that the maximum achievable amount of
energy to be derived from renewable sources in the future will be 10 000 TWh, or
10 per cent.”
Letters : Bouncing back
foop@sg4.pcy.kcl.ac.uk
You mentioned Peter Robinson’s “receipt advice” e-mail from “Postman Pat”
(Feedback, 17 January).
I suspect this is the programmer’s reaction to a
well-known phenomenon in the computer world, which is often discussed in a
systems administrator’s newsgroup I read.
When e-mail messages bounce, the bounce message is automatic and comes from a
specific address (usually “postmaster”). Many recipients of bounce messages,
unaware that the process is automatic, send a reply. These replies are often
long and complicated, and almost invariably amusing.
Their tone varies from pleading (“I know she worked at a university in
London, and her name is `Tracy’. PLEASE help me find her e-mail address”) to
abusive (“Don’t tell me that it doesn’t exist. It *does*!!!!! I sent a message
only a week ago and it got through!! You’re obviously trying to censor
me!!!!!!”).
Bounce messages were originally fairly terse鈥攄esigned by computer geeks
for computer geeks. Now, they’re becoming more readable and often offer helpful
information as to what the reason for a failure might be.
Letters : Ants online
Bulli, NSW
In regard to the article “There’s an ant in my phone”
(24 January, p 32), you
may be interested to know that the Unseen University in Terry Pratchett’s
Discworld novels has a computer, called Hex and invented by one Ponder Stibbons,
which uses ants as carriers of information. A number of books written by
Pratchett have developed the idea to a highly sophisticated level.