Â鶹´«Ã½

In his response to the discussion of Victorian distortions of biology, Jonathan Wallace questions the idea that a feminist input is needed, on the grounds it may lead to wrong conclusions ( Letters, 9 April ). On the contrary, I would say a larger number of perspectives can produce a more complete picture. With more …

Noting the "Organic mineral bonanza on Mars" found by NASA's Curiosity rover in Gale crater makes me wonder if there have been any attempts to determine concentrations of the radioactive isotope carbon-14 ( 19 March, p 14 ). If any microbes on Mars are like Earth's, they will absorb and assimilate carbon, including carbon-14, during …

There is more to the nuclear power debate than economic circularity advantages raised by earlier letters ( Letters, 5 March ). Energy production should be clean, safe, renewable, secure and as cheap as possible. Nuclear isn't clean, given its waste problems. It isn't safe, as evidenced by major accidents, nor is it secure – plants …

In his article, Timothy Revell asks: "Mathematically, infinity is useful, but does it really exist in the physical world?" This question raises issues beyond the nature of infinity, questions about the ontology of mathematics and its relation to physics and the physical ( 16 April, p 38 ). Our knowledge of arithmetic seems to be …

Infinity has always been an uplifting, almost spiritual, concept for me, so I was interested to read about the knots mathematicians tie themselves in while trying to define its mathematical nature. The concept of nothingness is harder for me to live with than infinity. It feels scary, unnatural and dispiriting.

Mathematics can't address infinity as suggested. That infinity comes in different sizes is a nonsense because infinity isn't a number. Any infinity that can be doubled, or broken down into a great number of smaller numbers, isn't an infinity to begin with.

Having grappled with infinity for as long as I can recall, your cover line, "A new answer to the largest question of all", sent me eagerly seeking the article. Alas, I was disappointed. The big problem, as I see it, lies in attempting to analyse infinity as if it were an actual, tangible mathematical entity …

Thanks for the very interesting article highlighting some of the difficulties with infinity. Quite a few mathematicians have problems with the concept of infinite sets and Norman Wildberger at the University of New South Wales has released a number of videos that have elaborated at great length on infinity, the difficulties of real numbers, functions …

You reported on preferences for open-plan spaces in your look at the psychology of design, often based on virtual reality experiments ( 16 April, p 44 ). Yes, most people would rather work in a brightly lit open space, but only up to a point. In reality, real-world studies show that when it comes to …

The article "Better by design" at last presents a science-based approach that takes architecture and interior design seriously. I particularly valued the "habitat theory" of open-plan living. I have recently introduced wood-frame glass doors into the ground-floor living areas of my dual-aspect house after watching a video of a Frank Lloyd Wright house in the …