Letters archive

The Letters editor Every now and then we receive letters that don't quite belong on the letters page but that we would love to publish anyway. As it's Christmas we have decided to ignore our own rules and start with a few of them. Thanks to everybody who has written to us this year – …

Graham Clarke of Edinburgh, UK, wrote to tell us about a remarkable three-level coincidence that he noticed when working on one of our Enigma puzzles. The number 113 is prime, as is its mirror, 311. The squares of each, 12769 and 96721, are also mirrors of each other. For the treble, this second pair are …

The Scientists at CERN fill with pride, As the Protons are set to collide. They'll crash and they'll splatter, When they measure the Matter, Will the Higgs be revealed, or still hide? Keith FitzPatrick, The Netherlands

Did nature in creation spurt with math as part of One, Or are numbers a religion making all obey to Sum? Whatever be the truth of it I never feel less grave, Than when Nature to The Numbers, refuses to behave. Anna Tambour, Australia

When you planned your super collider, we doubted it would work. Now we marvel at the way you hid its magnets underground, energised its vital tubes in secret, threaded complex circuit wires, connected all the parts. Then you flipped the switch, caught me in its gravity. You reassured it would not be the end of …

Your Instant Expert on the evolution of language says the selection pressures that encouraged our heavy reliance on speech rather than sign language remain elusive (4 December) . I have never used sign language, but it must be tricky addressing someone who is not already looking at you. I suppose there is no equivalent of …

Since I used to farm chrysanthemums, growing around 80,000 cuttings a year, I was interested in your report on bean-bag "hands" for robots (30 October, p 23) . Each of my cuttings was handled five times, which cost money and increased the risk of spreading disease. I followed every avenue searching for methods to mechanise …

Kate Douglas's description of the evolution of human culture (20 November, p 38) reminded me of an analysis I reported in the book Greenhouse Effect, Sea Level and Drought . This used archaeological and historical data to show that the world population growth curve is punctuated by steps of cultural evolution, each represented by a …

The "Frozen solid" part of your article on life in extreme conditions (13 November, p 36) reminded me of a sick goldfish I kept in isolation in a plastic bucket of water one very cold winter. The bucket of water froze solid for several weeks, goldfish and all. When the water eventually thawed, to my …

Visual illusions may be more than a by-product of efforts to "make sense of partial visual details" as you quote Susana Martinez-Conde saying (18 September, p 38) .It may be that our brains actively seek differing interpretations of the same image. It would surely be an advantageous trait for any prey species whose foe had …

It is apparently becoming more popular to claim that belief in God or gods is hard-wired as a result of evolution, as mentioned in Michael Brooks's review of Jesse Bering's The God Instinct , (20 November, p 51) . I was lucky enough to have parents who inflicted on me neither religious nor atheistic beliefs, …

Feedback ought to have checked the dictionary before ridiculing the "sensible section" of Robert Caillau's barbecue-thermometer (22 May) . I refer you to the full definition in the Oxford English Dictionary, 2nd Edition, Volume XIV: "Sensible heat: heat perceived by the touch and measured by the thermometer".

I liked Marcus Chown's analogy of a pair of gloves to explain chirality (15 May, p 28) but you don't need the mirror he suggests using to turn a left-hand glove into a right-hand one: just turn it inside out. It might not help to solve his "fiendishly complex" calculations, but it has a practical …

Feedback refers to the instance of a paper authored by two different men, both named Alan W. Harris (8 May) . I am one of two G. S. Brimbles living in Adelaide, South Australia. On one occasion we both booked the same flight. An amused check-in operator seated us together so we could meet.

When reading of the difficulties that may beset cellphone networks, I noticed the size of the feet of the young men in your photograph (30 October, p 44) . The women's feet look normal, but I'd guess the men's are UK sizes 15 to 20. Is this the camera angle, are they clowns' shoes, or …

• Bob Coecke and Samson Abramsky used a graphical form of category theory in their new approach to allow computers to understand language (11 December, p 10) .