Honest bankers
I find Ian Stewart’s use of “the set of all honest bankers” as an example of an empty set (19 November, p 44) not in the least amusing, and deeply insulting to the hundreds of thousands of men and women in banking who have devoted their careers to helping customers, whether they be in the retail, corporate or commercial sectors.
Most of these people joined the profession because they share a commitment to the standards of honesty and integrity that have long been the hallmark of the banking industry, and indeed without which banks could not exist.
A very cheap jibe, not at all worthy of a place in your excellent publication.
Speed checks
In the story on further observations of neutrinos beating the speed of light (newscientist.com/article/dn21188), Luca Stanco of the National Institute of Nuclear Physics in Italy says: “I’m not so happy. From a theoretical point of view, it is not so appealing. I still feel that another experiment should make the measurement before I will say that I believe this result.”
I am a bit ignorant as to why this would not be so appealing. Regardless, I agree more testing should occur – the more it can be repeated the more solid the evidence is. Either way, in the end it will be exciting to know if neutrinos do or do not move faster than light.
From Andrew Martin
It seems string theorists continue to grab any morsel of scientific headline to prove their theory. If neutrinos are beating the speed of light by dropping out to another dimension for a short cut through the “brane” (1 October, p 6), then how do they know when to come back to “our” dimension to hit the neutrino detector?
Melbourne, Australia
Just say no
Reading Susan Watts’s piece on the use of cognitive-enhancing drugs (19 November, p 32), I was both excited and shocked. I am studying management accountancy, and happy to consider things that would give me an edge over other students. Yet performance-enhancing drugs are, for me, a step too far.
The ethics of using drugs such as modafinil would appear to be in the same realm as cyclists using the hormone EPO to boost red blood cells, or the steroid nandrolone. I see it as highly unfair that what I hope to achieve through application, study and graft (with the odd cup of coffee), others might “cheat” their way to.
After writing the above, I have just highlighted a culturally accepted hypocrisy: I am typing this with a beer at hand to relax after a long and stressful week. I will undoubtedly have a coffee in the morning to perk me up.
Cost of meat
Further to your look at the environmental impact of global meat consumption (19 November, p 12), I would like to take issue with the claim that “80 per cent of agricultural emissions come from meat production”.
In total, the agricultural sector emits around 25 to 32 per cent of global anthropogenic greenhouse gas emissions. Crops emit 14 per cent () and livestock emit 11 to 18 per cent depending on how emissions are attributed (, , ).
The emissions from livestock can be divided roughly as: 25 to 30 per cent methane from the digestive systems of ruminants; 30 to 35 per cent nitrous oxide from manure management; and 40 per cent from carbon dioxide produced by land-use changes from grazing and feed production (). The emissions from land use changes carry a lot of uncertainty.
Emissions can also be divided by species and product. For example, the dairy sector is responsible for roughly 15 to 27 per cent of greenhouse gases from livestock (), while pigs and poultry are responsible for 10 to 20 per cent of the emissions. Even if beef cattle represent between 50 and 60 per cent of livestock emissions, this will translate roughly into a figure closer to 30 to 35 per cent of all agriculture emissions.
The editor writes:
• Molly Jahn of the University of Wisconsin-Madison has asked us to point out that she is not the source of the part of our story that said 80 per cent of all agricultural emissions come from meat production. That figure is from
From Graham Cox
Your story states that “we can’t all go veggie”. We can, scientifically speaking. It should have said “we are unlikely all to go veggie”.
Hothfield, Kent, UK
Hero to zero
It is a shame that the fascinating article on zero (19 November, p 41) did not mention the 6th-century monk and scholar Dionysius Exiguus. Although he wimped out big time by not having a year zero when he split the calendar into BC and AD, instead starting the Christian era on 25 March 1 BC, the feast of the Annunciation, he did use zero in his calculations of the dates of Easter, a calculation which is still in use.
This was despite him not having a numeral for zero and using the words nulla or nihil to represent it. I believe this was the first use of zero in the west, several centuries before Fibonacci.
The editor writes:
• While Dionysius used zero to date Easter, he was by no means the first in the west to recognise its usefulness in such calculations while denying its existence as a number. Greek astronomers as far back as Hipparchus in the 2nd century BC were borrowing the Babylonian zero for calendrical calculations, but translating the results back into their own number systems with no zero as soon as they were finished.
From Ken Green
On the subject of zero, in general it is necessary to have rules which forbid certain manipulations using it. This is why the electronic calculator comes up with an error message should you try to use it in division.
The early mechanical calculator was not blessed with this facility and it went berserk whenever someone set it to divide by zero.
Tintagel, Cornwall, UK
Taste test
There are currently over 7 billion people on this planet, and almost as many working taste sensors. Do we really need a “magnetic tongue” to do the job for us (5 November, p 23)? Considering food manufacturers are making products for humans, surely the human tongue is the best judge of flavour.
Early innovator
I was interested to read about Chinese pharmacologist Tu Youyou, who received the 2011 Lasker award for the discovery of artemisinin, an antimalarial drug that has helped to save millions of lives (12 November, p 46).
Tu led the effort in China that led to the development of artemisinin from extracts of the plant Artemisia annua. In the long history of women’s contributions to science, another name could also be mentioned in connection with this. The genus Artemisia was, I believe, named after Artemisia II of Caria, a botanist and medical researcher of antiquity who was queen of Caria in what is now Turkey.
Artemisia, who died around 350 BC, is better known for building one of the seven wonders of the ancient world, the Mausoleum of Halicarnassus, but she also deserves to be remembered as a scholar and one of the women active in science and medicine during antiquity.
I quit
Like other readers, I was shocked, but not surprised, by the utterly naive letter from Quentin de la Bedoyere asserting that “science, by definition, has nothing to say about the spiritual aspects of humans” (15 October, p 33).
As a Roman Catholic priest who had been religious for 30 years, this is an attitude I was finding increasingly impossible to tolerate. It was partly because of the expected allegiance to fundamental theological doctrines which were clearly incompatible with modern knowledge that I finally decided to leave the church.
Animal farm
In response to Peter Morris’s letter about donating his mortal remains to a body farm rather than opting for a traditional burial or cremation (19 November, p 38), I suggest he looks at the University of Central Lancashire in Preston, UK, which has a body farm, or at least something their website calls .
It looks like they use animals rather than people, but you could always offer.
At sixes and sevens
You report on an artist who depicted mountains on Earth as 107 centimetres rather than the more accurate 106 centimetres, because “7 was so nice and lucky” (12 November, p 52).
Surely this could have been resolved without geo-engineering by using millimetres, the preferred SI sub-multiple.
Endless oceans?
In his review of Robert Laughlin’s book Powering the Future, Fred Pearce summarises the author’s view as “ultimately the planet won’t care much about our carbon dioxide emissions” because the gas will all end up in the oceans (1 October, p 46).
This is not correct. If we burn all our known fossil-fuel reserves and add the CO2 to the seas, the eventual concentration of CO2 in the air will be twice pre-industrial levels. Dissolution of carbonate sediment and reef by the lower-pH ocean that results from more CO2 can mitigate this by shifting the balance of carbon species in the sea, allowing it to soak up more CO2.
But even if this happens, the level of atmospheric CO2 will be about the same as today, which will still mean a warmer world than in pre-industrial times, with a higher sea level.
For the record
• The story on atoms forming unexpected bonds at temperatures close to absolute zero (19 November, p 8) should have said that carbon has four electrons in its outer shell.