Editor's pick: It is the world that has failed the rainforest
As Mary Menton and Felipe Milanez say, the policies of President Bolsonaro of Brazil may threaten the Amazon rainforest (10 November, p 24). But it is global policy on carbon pricing that fails to protect the forest. The points out that if carbon dioxide emissions are priced at $20 per tonne, a hectare of rainforest should be worth up to $15,000. Yet it may be chopped down to grow soya beans or graze cattle with a market value of $300 per hectare. The Prince of Wales calling this “the greatest market failure in history”.
If we had a carbon tax on emissions and used it to pay just 5 per cent interest on the “capital” of stored carbon in the “bank” of the rainforest, then a hectare of undisturbed rainforest would be worth $750 a year and nobody would dream of cutting it down for beef or beans. Instead, we ask Bolsonaro to hold back from exploiting an asset that is garnering no reward, while other nations benefit from the free contribution to climate stability represented by Brazil's trees.
Gravitational wave critics respond in turn (1)
Michael Brooks's recent article on reports of gravitational wave detection (3 November, p 28) and a response from the LIGO and Virgo teams (Letters, 24 November) raise a number of interesting questions.
If, as Brooks reports, the “residuals” for the event labelled GW150914 were published for the sole purpose of illustration, what are the correct data sets and why has LIGO not made them public? If LIGO believes that our analysis of correlations between residual noise at different detectors is incorrect, why have they not stated clearly where we have made a mistake? And if our calculations are correct, why does LIGO consider this statistically significant 80 per cent correlation irrelevant for the interpretation of the observed signal?
Despite LIGO's claims of openness, we have been unable to identify members of the collaboration who can speak authoritatively and officially on LIGO's behalf on matters of data analysis. We believe it would be useful for LIGO to identify some individual or a group of scientists to represent it with the aim of resolving these differences of interpretation in an appropriately professional manner.
Gravitational wave critics respond in turn (2)
I remember marvelling at the ability of the gravitational wave analysts to tell us not only that a squiggle represented the collision of two black holes, but also their respective solar masses, from half a dozen wobbly peaks standing out from a mushy background. I thought that was wonderful.
Now Michael Brooks informs us that the experimenters first calculated what they might expect to see, then subtracted that from what they actually saw, and made profound assumptions from that. I remain very confused and not a little disillusioned.
First class post 鈥� 1 December 2018
I have the coordination of Mr Bean going forwards – don't make me do that as well
Katya von der Goltz King by a finding that walking backwards can boost short-term memory (24 November, p 20)
Florence Bell, an unsung physics and DNA pioneer
Valerie Jamieson reports real-life experiences of women in physics in her article on why there are so few women in that field (10 November, p 32). The physicist Florence Bell would have agreed.
Her PhD supervisor, William Astbury, declared that “there is a creative spark in the male that is absent from women, even though the latter do such marvellously conscientious and thorough work after the spark has been struck”.
When Bell gave a presentation about her work at an Institute of Physics conference in Leeds in 1939, the local press reported under the stunned headline “Woman scientist explains”.
She would have wanted to be remembered, though, for helping to lay the foundations for one of the biggest scientific discoveries of the 20th century. Her PhD research included taking the very first successful X-ray diffraction images of DNA – which helped to pave the way for later X-ray work on its structure by Rosalind Franklin and Raymond Gosling.
While most scientists at the time thought DNA to be a boring molecule of little interest, Bell recognised that, in conjunction with proteins, it might play an important role in biology.
Sadly, this promising work was brought to an abrupt end by the second world war: she served in the Women's Auxiliary Air Force, then emigrated to the US and gave up science to raise her family. Her thesis has just been made available online by the University of Leeds at .
I nominate Rosalind Franklin for the 拢50 note
Alice Bell suggests that Dorothy Hodgkin should be on the Bank of England's new £50 note as a pioneer in the field of X-ray crystallography (10 November, p 24). I suggest that the most appropriate scientist to feature would be Rosalind Franklin.
She was a vital member of the team that worked out DNA's structure, but the only one not to share the Nobel prize, simply because of her early death. This is an opportunity to give her the recognition she deserves – not to mention acting as a role model for female would-be scientists.
Elon Musk's satellite plan is a great deal of garbage (1)
The plan to put 4425 satellites in orbit for Elon Musk's “space internet” seems impressive at first (10 November, p 5). But it is not just the financial cost that will be high. Does SpaceX plan to retrieve and recycle obsolete satellites?
There is too much debris in orbit as it is. Simply shunting old satellites to a different orbit is surely not a long-term solution. Besides, if Musk litters orbit with debris, he will make his own Mars plans more challenging: space vehicles will find it harder to plot a safe path through all the junk.
As for all manufacturing, plans should be made at the design stage to retrieve and recycle an object at the end of its useful life. Sports cars are included.
Elon Musk's satellite plan is a great deal of garbage (2)
Musk's plans require keeping 4425 working satellites in orbit. If each lasts an average of five years, the replacement rate would be 17 satellites a week. This would be several times the current total world launch rate for all purposes.
The Polynesians could help us read Inca writing
Daniel Cossins discusses the possibility that Inca khipu might encode stories as well as numbers (29 September, p 33). Apparently those master navigators and peerless blue water sailors the Polynesians used knotted cords to encode sailing instructions and these have been used for modern trips in recreated voyaging canoes. It seems the Polynesians reached Central America and brought back sweet potatoes. These were ubiquitous when Europeans entered the Pacific and the Maori of Aotearoa/New Zealand had developed semi-temperate cultivars.
So it seems entirely possible that the Polynesians picked up the idea for knots from the Incas. As we know how to read knotted sailing instructions, can these be used to get an idea of khipu?
Yes, electric car owners may feel entitled to drive
Rosemary Sharples asks whether the lack of pollution at the point of use of electric cars makes their drivers feel entitled to make more and longer trips (Letters, 27 October). It is true with me. My mileage in my Nissan Leaf is greater than it was in my previous fossil-fuelled behemoth.
I now make more trips to the recycling centre, but carrying the same volume. I drive to local shops when they are cheaper than online deliveries. I joined a voluntary group that offers rides to the elderly. When disposing of my belongings online, I offer free delivery within the Leaf's range. These are all local journeys. My Leaf is one of the oldest in the UK and needs to be charged every 80 kilometres.
Further, I am concerned at the prospect of 100-per-cent-electric vehicles, with accelerations faster than a racing car, on the roads. Let's pray that safer self-driving vehicles form the majority.
More problems with economics as science
Features of economics that lead Sam Edge to state that it is not a science (Letters, 10 November) are found in much of the social sciences. Particles, planets, animals, chemical reactions and tectonic plates do not change their behaviour in response to new theories. Humans do change in response to economic theories. This is not necessarily a bad thing, but there is no theory capable of predicting where those responses will take us. As far as economics goes, we are the butterflies whose flapping triggers the storm.
Things that make your brain tingle
Michael Marshall discusses the “brain tingles” of autonomous sensory meridian response or ASMR (3 November, p 35). It seems these were what Vita Sackville-West, lover of her fellow-writer Virginia Woolf, had in mind in her 1950 radio talk “Walking through leaves”. As well as the sensation of the title, she mentioned the silky glide of a filing-cabinet drawer with roller bearings and putting on a freshly ironed skirt.
She also mentioned sensations that have the opposite effect, such as the nasty feel of treading on granulated sugar on a tiled floor.
Closer contact with brainwaves
Chelsea Whyte reports people collaborating to play the game Tetris via electroencephalography (EEG) caps to record brain signals and a transcranial magnetic stimulation cap to transmit them (13 October, p 5). These seem rather cumbersome.
Why not try receivers closer to the brain? People wear dentures right against the roof of the mouth. One day, miniaturisation and signal transmission advances in sensors could make it possible to use a tooth implant.