Â鶹´«Ã½

You report on a study suggesting we all perceive colours the same way, subjectively speaking. While the study seeks to offer an answer to this long-standing philosophical question, I have long pondered a similar one that can't be answered, or even tested, prompting me to frame it as a conjecture: that our sense of self, …

Penny Sarchet's review of the book Motherdom was refreshing. Having successfully medicalised pregnancy and childbirth, and so brought it under the control of mostly upper-middle-class, white, male, establishment authority figures, the same is being done with child rearing using spurious and misleading references to neuroscience. In the UK, at least, the education system has gone …

Regarding the story "Thousands join 'Stand Up for Science' rallies across the US". Given the often small long-term impacts and benefits of protest marches and rallies per se, plus the many hours consumed in their preparation and attendance, the most effective and efficient activity is to collect the contact details of as many attendees as …

The recent discovery that memory requirements for computation can be drastically reduced raises an intriguing question: could this principle help extend the lifespan of smartphones and the like? Many older devices struggle to run newer operating systems due to fixed memory constraints. If we could rewrite OS processes using the newly discovered approach, could this …

Researchers rendered mice unconscious – not benign – and then presented them to other mice who tried to resuscitate them. Such "research" won't benefit anyone, let alone save anyone's life, yet the mice were significantly disturbed. It adds only to the knowledge that despite "discovering" time and again that mice and other species have feelings, …

You quote a researcher saying "the recuperative behaviour isn't an analogue of CPR... but more like performing basic first aid to ensure an unconscious person can breathe". As a retired emergency medical technician, I can confirm CPR is, at its core, basic first aid to ensure a person can breathe and therefore the mouse behaviour …

Simon Goodman worries that quantum computers will leave our online bank accounts open to invasion. Actually, other types of cryptography have been developed to get around this vulnerability. Banks and e-commerce will start to use them instead of existing methods if and when necessary. The problem is that today's encrypted messages can be stored, and …

Carl Zetie suggests we "send 100 million sperm and eggs, not 100,000 people" to colonise an alien planet, but leaves the story of raising the offspring to others ( Letters, 15 March ). You would need a machine to provide food, made in situ, for the resulting infants, and much more. They may see it …

The idea of mirror cells producing long-lived pharmaceuticals seems a bit too much like the creation of "forever chemicals" to me ( 1 March, p 34 ).

I agree with Trevor Prew's sentiments on drains as an indicator of the first true civilisations. I would go slightly further and say that public conveniences are a key indicator. In my part of the country, funding of many public toilets was stopped and they closed. It seems we are less civilised than before ( …

Lisa Feldman Barrett is at Northeastern University in Massachusetts ( 15 March, p 30 ). Accretion disc light from a black hole in galaxy 3C 186 was blueshifted relative to its galaxy as a whole ( 15 March, p 19 ). Pufferfish acquire the toxin tetrodotoxin from their diet, rather than producing it themselves ( …