91É«ÇéƬ

Colin Barras's intriguing article on the relationship between human and non-human culture may have missed a significant difference. Human cultures, and the development and manufacture of technologies within them, depend upon a division of labour. No one person is typically responsible for the whole thing( 5 April, p 36 ). To take the example of …

Name/address withheld on request I have been a blood donor since I was 17 (I am 63 now). I was recently told that I no longer needed to give regular donations, as they have sufficient supplies of my blood type( 22 March, p 18 ). I have always felt it to be a good thing …

You say there is no clear reason why the behaviour of subatomic particles can't be governed by deterministic laws, and the fact that they aren't demands an explanation( 19 April, p 28 ). Well, here is one: we are working our way down the chain of causality. This will either end or it won't. If …

Could the ancient Greeks have invented quantum theory? While a full-blown version probably couldn't have been formulated much earlier than it was, all you would need to postulate a sort of quantum theory would be to assume that nothing in the real world can be infinite. This probably isn't an unreasonable assumption. After all, if …

In discussing quantum computing, the comparison always made is with digital computer efficiency. Numbers between 0 and 1023 can all be encoded at once with 10 qubits, while digital computers need 10 bits just to be able to encode any one of those numbers at a time. But what about analogue computing? Just one capacitor, …

Levitation of moon dust at lunar sunrise and sunset is surely partly down to the pyroelectric effect, which induces an electrostatic charge on particles when warmed or cooled that then causes repulsive forces and floating dust. This can potentially coat scientific instruments. A possible means of suppression may be to seed the local area with …

Even if there is doubt about how much carbon dioxide trees will soak up in a warmer future, they can still help us deal with climate change. Forest management strategies can help buffer (if not prevent) droughts, floods and heatwaves, and milled wood incorporated into structures provides a carbon sink capable of storage over decades …

Your feature explained a concept that was new to me, a form of evolution in chemistry as a potential origin of life on Earth. The idea dates back to at least 1944 and Erwin Schrödinger's book What is Life? . I want to thank your contributor Elise Cutts for her brilliant prose, allowing one of …

It is brilliant to know that quantum Darwinism, which seeks to bridge the divide from the quantum realm to classical reality, is proven mathematically( 12 April, p 8 ). I hope one day we, the "classical" beings, will somehow experience the fuzziness of the quantum realm and see all its states at once. The crumbs …

The northern hemisphere is thought to store around 1.5 trillion tonnes of carbon in permafrost ( 5 April, p 17 ).