Letters archive

Gaia Vince suggests the use of land in the far north and south of the globe for food production, should farmland be lost through flooding or desertification (28 February, p 28) . The use of a Peters projection map rather than a Mercator map like that in the article would have shown that there is …

I was astonished by Robert Pool's account of Thomas Joiner's theory that anorexics find suicide easy because they are used to pain (28 February, p 37) . It's actually much simpler than that. When I was anorexic, the constant mental agony was so intense that the only relief from it was physical pain. I was …

Martin Rees's article on mathematics (14 February, p 36) prompts the question: why is mathematics so effective in explaining the physical world? We observe that the natural world is not entirely random, and see lots of structure and organisation – patterns, in other words. We observe that snowflakes often have a hexagonal structure, and that …

In her article on dyscalculia, Laura Spinney ignores the differences in the way we process and organise auditory and visual information (24 January, p 40) . The auditory system organises sounds according to their relationship in time, which is one-dimensional. The visual system organises images according to their relationship in space, which is three-dimensional. Almost …

Michael Brooks reports the contentious claim by Alison Pease that "Mathematics is not a discovery. It is something we invent" (28 February, p 34) . Clearly, the rules of mathematics apply prior to their discovery; they would not if they were merely invented. The Pythagorean relationship was there at the beginning of the universe, for …

In relation to Stuart Clark's story on the Lagrangian points (21 February, p 30) , the gravitational fields of the Earth and sun do not cancel each other at the Lagrange points. They add up to a net acceleration towards the sun that is of the same magnitude as that experienced by the Earth. This …

Anil Ananthaswamy interviews the next head of ATLAS, and the first question is: "What are your thoughts on becoming the first woman to head a particle physics experiment at the LHC?" (28 February, p 26) . For a moment there I thought you had morphed into a women's magazine circa 1970. What on earth has …

In Julian Smith's fascinating "Ted's excellent adventure" (31 January, p 36) , the diagram of Ted Ciamillo's submarine shows the rear fin as rigidly attached to its propulsion rods. This can't be how it works. Instead of constantly thrusting the water to the rear, half the time the attachment would propel the water forward, causing …

Stephanie Pain wonders why 1708-09 was the coldest winter in Europe during the past 500 years (7 February, p 46) . The coldest years of the Little Ice Age, based on temperature records inferred from stalagmites in Spannagel cave in Austria, included 1695 and 1714-16. The eruption of mount Fuji in Japan on 16 December …

• The picture illustrating the Insider article on Scandinavia (UK edition, 14 March, p 50) was actually UNIS, The University Centre in Svalbard, Norway. • In "Surviving in a warmer world" (28 February, p 28) we said that you could use "solar energy to split water in fuel cells". We meant to say "using solar …

Gaia Vince's article on what we might expect to happen "geophysically" as well as socially in the coming decades was sobering but not completely disheartening (28 February, p 28) . However, by provisioning for an anticipated population increase to 9 billion people within about 50 years we are ignoring a crucial fact: we don't have …