Editor's pick: Scuba divers on a mission
Your interview with Bob Brewin about surfers’ mission to log marine data (28 November, p 31) struck a chord. Such measurements by others using the marine environment.
As a scuba diver, I log my dives 鈥� recording information enables repeat dives to be safely executed and gives proof of a diver’s experience and their capabilities. The logs follow a standard form that includes dive time, depth, site information, location, date, equipment and weight used. It also records environmental information: air temperature, sea surface and often bottom temperature, wave state, current, surge and weather.
For many years, divers have used dive computers to plan and execute dives, and these automatically sample and record the depth, temperature and decent and ascent rates.
Here we have an amazing data set of coastal information sitting in log books and on dive computers, going back years. Voluntary information from divers is already collected into , a national system used to help us understand our coastal marine habitats, run by the Marine Conservation Society.
The information has been significant in providing evidence to support the establishment of Marine Conservation Zones.
Hurstpierpoint, West Sussex, UK
Romans knew of torture's flaws
Although the ancient Romans used torture as a regular means of interrogation, they were well aware of its defects (14 November, p 44). The legal writer , who died in AD 223, declared: “It is a chancy and risky business and one which may be deceptive. For there are a number of people who, by their endurance or their toughness under torture, are so contemptuous of it that the truth can in no way be squeezed out of them. Others have so little endurance that they would rather tell any kind of lie than suffer torture; so it happens that they confess in various ways, incriminating not only themselves but others also.”
Glasgow, UK
<b>First class post</b>
Why did WHO not stop the use of antibiotics to promote growth in animals bred for food?
Charlotte Walters the had acted to save antibiotics (12 December, p 7).
Before a universal basic wage
Federico Pistono argues for a universal basic income (3 October, p 28). Back in 1978, I wrote on this subject, but called it a Basic National Wage (BNW) and I intended it to counter the work problems expected from microelectronics.
Industry is the creator of wealth and so ultimately pays for the unemployed. This should be recognised in accounting procedures. The BNW would be paid by the state to those who are unemployed and those who are employed, with employers topping it up so their workers are paid a similar amount to present salaries. The extra cost to give someone a job would then be less, as would the monetary benefit of making people redundant.
Investment in equipment such as robotics would therefore be delayed until it made a net saving. Overall there would be a greater utilisation of resources 鈥� plus the psychological benefit of providing more employment. One issue to consider is the method of taxation to pay for it, to make sure it does not penalise those who employ more people.
Haywards Heath, West Sussex, UK
Another reason to do science
Bill Summers claims “science serves no practical purpose unless it leads to a design” (Letters, 28 November). Science serves many practical purposes that have nothing whatsoever to do with design. I refrain from standing next to sources of gamma radiation precisely because a scientist discovered that it would harm me. I find that a very practical purpose.
Stevenage, Hertfordshire, UK
How low can we go, again?
We enjoyed the reference to the lowest note sung in opera, the low F in O Isis and Osiris from Mozart’s The Magic Flute (Letters, 31 October). Such deep notes convey a sensation of wonder, novelty, aesthetic beauty and menace. The 64-foot organ pipe (Gravissima) of the Hill Organ in the Sydney Town Hall is an example, with the frequency of one of its harmonics down to 8 hertz, which induces a mix of physical vibration as well as perceived sound. Elephants, moles and ferrets perceive, as sound, frequencies as low as or lower than 16 Hz.
The song Drinking by the German bass Ludwig Fischer was a favourite of the Australian basso profondo Malcolm McEachern. A 1930s English Path茅 documentary film shows him singing it. Then, having plumbed the depths of the final deep F (43.6 Hz) at the end of the first verse, McEachern casually suggested to his pianist that they “see how low we really can go” 鈥� and sang it two tones lower, right down to the final note, D1 (36.7 Hz) which has a wavelength of 939.8 centimetres. Is this the lowest frequency achievable by the human voice?
South Brisbane, Australia
How low can we go, again?
The letters on hearing giraffe vocalisations at 92 hertz (Letters, 31 October) treat sound as if it contains only a single frequency. Vibrating objects produce a series of harmonics that are multiples of the fundamental frequency. The brain interprets this to give the sensation of the fundamental frequency 鈥� often even when this is not in fact present.
Cardiff, UK
To be convinced beside the seaside
William Kirby advises against building nuclear power stations on coasts (Letters, 28 November). But to do so is to demonstrate the courage of one’s convictions. Nuclear power stations reduce carbon emissions, which should lead to safer coastal areas. This reminds me of the idea that cars should be manufactured without seatbelts, and instead should have spikes projecting from the centre of the steering wheel.
Houston, Renfrewshire, UK
There is more than one other way
Al Cowie writes “In the rest of Europe, the market dictates health services… The result… is a better system than the NHS, cheaper…” (Letters, 14 November). One can discuss whether health services elsewhere in Europe are better than the UK NHS, but to say it is “cheaper” does not stack up with the figures.
Where I live in Switzerland my wife and I, both retired, pay about $12,000 a year for minimal insurance. The fact is that the cost of health services is growing in all countries at a much higher rate than incomes are growing. This will be a problem in the future.
Ipsach, Switzerland
Behold the standard eye!
A smile came to my face when I read your response to Peter Holness’s question about fundamental units, which noted that the candela “is defined with reference to the single frequency at which a standard eye is most sensitive” (Letters, 7 November). I envision the tableau in S猫vres, home of the , a few decades from now: the chief metrologist, in front of assembled international colleagues, takes out the standard eye, polishes it and places it in the measuring apparatus, ready to calibrate the major national reference standards for the candela.
Thank you for that smile!
Vienna, Austria
Dogs have trained humans, they say
The article “If I wag my tail will you do it for me?” described 10 wolves and 20 dogs being given a puzzle to solve (19 September, p 14). Eight wolves were able to do so, but only one dog managed it without human guidance.
I recently found time to discuss this with my dog. I explained to her that my interpretation is that humans are clearly cleverer, on the whole, than dogs.
Her reply was that au contraire (she’s very cosmopolitan), precisely the opposite. Dogs, she said, have successfully trained humans to do their bidding and this demonstrates their superior intelligence.
Ottawa, Canada
What came before the big bang?
What came before the big bang (5 September, p 30)? Nothing. Of course this “nothing” is not the classical “no thing”. Rather it is a form of the quantum vacuum with particles and antiparticles zipping in and out of existence according to the program of Heisenberg’s uncertainty principle. But neither is this “nothing” the quantum vacuum as conventionally conceived.
The uncertainty principle depends on arbitrary constants, notably the Planck constant h. It sets the scale of our universe. Before the constants are specified with the values they have in our particular universe, , the state of the quantum vacuum is formally undecidable. So the answer to “what came before the Big Bang?” is undecidable. There were no particles and no laws of nature governing their behaviour.
This resolves a long-standing conundrum regarding the apparent low entropy of “our” existence in the big bang. A system whose state is undecidable has only one micro-state: namely “undecidable”: its entropy is zero.
To comprehend any beginning of any universe we need to learn how to incorporate undecidable values in our formulation of the laws of nature. Then, along with physicist Eugene Wigner, we shall truly marvel at “the unreasonable effectiveness of mathematics in the natural sciences”.
Salisbury, Connecticut, US
<b>Not quite a wasteland</b>
Your Field Notes from SNOLAB 鈥� the Sudbury Neutrino Detector 鈥� (25 April, p 14) located it in the “frozen Canadian wasteland”. I was born in the city of Sudbury. Its population of 100,000 has a university and tourist attractions such as Science North… and the Big Nickel, a large replica of Canada’s five cent piece. I must, however, admit that I left.
Sydney, Australia
<b>For the record</b>
鈥� There were, in fact, 195 countries represented at the Paris climate summit (5 December, p 6).
鈥� Spot your bane: typhoid is not generally spread by insects, typhus is (7 November, p 36).