Letters archive

The universe is abnormal, in that measurements of most things don't fit a normal curve, where the mean (average) and the median (typical) are the same. So your editorial's claim that it is "unfair" that bigger countries win more medals is irrelevant. Perhaps a metric such as medals per million people would be better ( …

Scanning "The smarter way to a fitter you", I discovered a comprehensive account of most aspects of exercise. However, apart from home-based game playing and pedometer measures, there was no mention of domestic work ( 27 July, p 32 ). There seemed to be a theme of avoiding boredom in exercise pursuits, and maybe that …

Dave Johnson wonders if time can flow backwards in some small pockets of space, given increasing entropy equates with time's arrow. This shows how intuition fails with huge and tiny numbers. When two atoms bounce off each other elastically, their energies tend to be more equal afterwards (increased entropy). When, by chance, they are less …

When I read that the American Academy of Pediatrics was recommending weight-loss medication for children aged 12 and up, my moral stance on this initially made me cringe. However, after completing the article, I support this idea despite reading contradictory advice from the US Preventive Services Task Force, which cites insufficient evidence and suggests long-term …

As the article "Super AI is still sci-fi" noted, the term "artificial intelligence" is little more than a good branding exercise. This is much more attractive to investors than using facts about machine learning pattern recognition algorithms with more powerful graphics processing units. When it comes to "AI", there is nothing approaching "intelligence", so why …

From From Paul Whiteley, Bittaford, Devon, UK I read with horror about plans to create an AI model of Alan Turing, effectively putting words into the mouth of someone long dead. ( 17 August, p 21 ) We will never know what goes on inside the mind of a genius – that is what sets …

Matthew Sparkes is too cautious in opposing an AI recreation of Alan Turing. A tour of Bletchley Park where he worked pays homage to those clever and dedicated code breakers who reduced the length of the second world war by two years, but it can be a little dry. A chatbot conversation with an interactive …

It seems highly problematic to allow the ISS to partially burn up in our atmosphere and then crash on Earth, once it is no longer deemed viable for science. The danger, pollution and disruption created, not to mention the waste, would be absurd considering there may be a better option: why not strap on engines …

Bryn Glover mentions the idea of weights being lifted in order to store energy, suggesting putting a falling-weight system in every house, lifted by energy from solar panels and allowed to fall during the night to provide heat and light. Such an arrangement could indeed provide light, but definitely not heat. It turns out that …

Global heating is causing me a certain amount of inconvenience. I avoid flying, use public transport, recycle plastic and so on. However, if I am living in a simulation, a suggestion that several readers have raised recently, why should I bother? Whoever or whatever created the simulation can always program a better world next time. …