Letters archive

I question Alberto Fairen and Dirk Schulze-Makuch's statement that planetary protection, such as spacecraft sterilisation, prevents missions from going to particular places on Mars (6 July, p 8) . Current engineering cannot get us there, and the cost of developing such capabilities is many times the cost of planetary protection. In addition, the cost of …

Using 3D gestures to command a computer, as you report (25 May, p 40) , gets a 3D gesture from me: thumbs down. I am perfectly happy with the 2D gesturing on my touchpad. What I would like a computer to do, however, is sense my anger. I get angry when I have several applications …

I see that the wretched Schrödinger's cat has once again made an appearance (3 August, p 15) . I recall as a student experiencing great difficulty getting my head around the idea of a superpositioned feline, while having only small problems with the actual physics it was supposed to clarify. I once considered founding a …

I have sympathy for the "crusaders" who feel they are being denied treatment for debilitating conditions using their own stem cells (10 August, p 42) . However, I also think that the US Food and Drug Administration (FDA) is taking a responsible position on the regulation of cultured mesenchymal stem cell transplants. These cells are …

However powerful and useful machine-learning artificial intelligence might be (10 August, p 32) , such systems also have a social impact. Their development is part of a trend towards the devaluation of skilled work and intellectual labour, from applications in translation to the creative arts. If nobody can make a living producing translations, or by …

Douglas Heaven inadvertently exposes the real danger of this type of AI, anthropomorphising complex algorithms. Machine learning, having no moral component, cannot be racist, as was claimed when Google's search function ended up directing ads asking "have you ever been arrested?" towards black people. What it did find was a correlation between having a black …

Gerald Legg's letter on eco-offsetting referred to greater protection likely to be given to chalk grasslands compared with disused industrial land reclaimed by nature ( 10 August, p 30 ). These grassland habitats are widely believed to have been deforested in Neolithic times, then kept in their current state by the grazing of farmed animals. …

Those who talk up fracking for shale gas (10 August, p 36) need to remember that we have already discovered five times more fossil fuel reserves than can be used if we are to have a reasonable chance of avoiding a 2 °C rise in global temperatures. We have to stop using oil, gas and …

All we will do with "fracked" gas is use it to continue avoiding dealing with climate change. So there is one fundamental aspect we need to address. We need to turn to our children and say, "So that we can save a few pennies on our bills, we'll be using all the shale gas as …

Comparing the physical and behavioural outcomes of the identical Kelly twins, one of whom will spend a year on the International Space Station, is an ingenious idea, given the genetic control (10 August, p 11) . However, it is not a novel notion. In 1972, astronaut Charlie Duke was on the Apollo 16 moon mission, …

The first thought that entered my mind when reading Douglas Heaven's article on designer organs, was "won't the athletes love this" (27 July, p 8) . We have already seen the use of performance-enhancing drugs and blood-doping; this will open up a new avenue for exploitation. Imagine an athlete who can enlarge or speed up …

Your editorial discussed how to deal with the abusive comments posted by some users of Google and Twitter (10 August, p 5) . For the last 10 years in every talk I gave about the web, the early development of which I was involved in, I have argued that the only fix to such problems …

The first time I heard about the fly-in-the-urinal means of manipulating behaviour (22 June, p 32) was a story about a bar with a cure for unruly drunks. The bartender would wait until a particularly bad boy went to the toilet. There was a bare wire strung across the back of the urinal, and the …

One solution to John Hardy's call to ban boxing because of the long-term risk of brain damage (10 August, p 26) : a blow to the head should be ruled a foul, and result in immediate disqualification. Harlow, Essex, UK