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Before Christmas, I was trying to explain quantum theory to the grandchildren and mentioned Schrödinger's cat, where the cat is both alive and dead before the box is opened. The children were sceptical. "Surely," they said, "if you carefully observe the box from the outside, sooner or later the 'cat' will interact with one or …

I have always found it strange when physicists say that they repeat quantum experiments. They repeat only certain parameters – they cannot ever repeat precisely the total physical environment. All they can do is repeat part of that physical environment. And that being the case, how can they be sure that aspects of the overall …

The trend towards SUVs that Anthony Laverty writes about is also evident here in Australia. But is it really bad for the planet? These SUVs tend to be diesel and therefore much more economical on fuel. I drive such a vehicle, a 15-year-old Audi Q5 SUV, and it delivers around 60 miles per gallon. That …

Oh, how we all too often underestimate the amazing abilities of insects. So, thank you for the excellent and informative article, "Heroes in disguise", on the fabulous hoverfly ( 29 November, p 42 ).

In response to Chanda Prescod-Weinstein's article on the research into dark matter: dark matter seems to me to be "aether with mass". It can't have any viscosity, for example, because if it did, normal matter passing through it would lose energy, which we would be able to detect. This applies at the cosmic scale even …

I was fascinated to read that a mosquito's proboscis can act as a surprisingly hardy 3D printer nozzle ( 29 November, p 18 ). I wonder if they can also manufacture a replacement mosquito proboscis?

Your article on when our feline friends spread around the world was very strange in repeating the long-debunked theory that cats have ever been domesticated. As every scientist, and indeed individual, who has ever met a cat with its servant knows, it is humans who were domesticated ( 6 December, p 9 ).

I am a scientist who has studied wild baboons in Kenya for over 50 years. While I agree with much of what Christine Webb says in her book, The Arrogant Ape , looking at humans through what I call my "baboon glasses", constructed over decades of research, shows just how exceptional humans are ( 15 …

Michel Brahic tells us that the formation of the last universal common ancestor from a soup of chemicals was "an extremely unlikely event, with a probability estimated at less than 1 in a billion" ( 6 December, p 30 ). He then goes on to speculate that life elsewhere in the universe, if it exists, …

Anthony Laverty's article "Running out of road", struck a chord with me as someone who hasn't had a car for most of my adult life and who now has a little Corsa that's about 15 years old ( 22 November, p 19 ). I think the psychology of driving is something that needs a lot …