Letters archive

There is an explanation for how a Japanese marketing gimmick came to be the source of the idea that taking 10,000 steps each day is good for you ( 11 September, p 38 ). It may be that 10,000 is an "easy number to remember", but in most European languages, it is no more so …

The story "Monkeys navigate using mental maps just like us" states that most animals don't possess mental maps of their surroundings ( 21 August, p 22 ). I beg to differ. We had a dog who had a highly developed mental map of our house and garden: whatever window I threw his ball out of, …

I was struck by Stephon Alexander's idea of the universe being a neural network ( 11 September, p 47 ). The concept wasn't fleshed out much in the article, and having scant knowledge of astrophysics, I'm not able to see how it would work. But perhaps there is a good example of this on our …

Despite what the preamble to the interview with Alexander said, growing up in the Bronx is typical training for a theoretical physicist. The Bronx High School of Science has produced eight science Nobel laureates – seven in physics and one in chemistry – the most of any secondary school in the world. The American Physical …

Alice Klein's article shows that a large-scale experiment to capture atmospheric carbon dioxide by seeding part of an ocean with iron to make phytoplankton grow has now, inadvertently, been carried out for us by Australian wildfires, thanks to iron-rich ash seeding the water there ( 18 September, p 8 ). Now, why should we hesitate …

I have to agree with fellow reader Sam Edge ( Letters, 4 September ). It was with some dismay that I watched Great Britain, China, the US, Japan and the Russian Olympic Committee claim medal after medal in the summer Olympics in Tokyo. I even wondered whether any other countries were competing. The games were …

In your excellent article on net-zero living, there is talk of a future with fewer cars, as many of them will be shared ( 4 September, p 34 ). Really? My impression is that most car owners love their vehicles and regard them as their private space, an extension of their homes. They are reluctant …

Your well-conceived feature "A day in a net-zero life" discusses heat pumps as though they only provide warmth. You seemed to refer to air conditioning as separate tech. However, a heat pump can both heat and cool a home. We have had one for a year. It has operated well through a cool winter and …

Much of the puzzle of quantum weirdness resolves if we notice that, for example, "collapse of the wave function" is a metaphor (and, I think, an unfortunate one – waves don't collapse, they break on shores and slap into sea walls) ( 28 August, p 34 ). This mean that asking what collapses when the …

I am somewhat worried that I am contributing to climate change since I am apparently farting seven times more on a plant-based diet ( 11 September, p 14 ). Please tell me that my vegetarian lifestyle will, to some extent, offset the damage from my noxious fumes.