Quantum thoughts
I was initially intrigued and then disappointed by Mark Buchanan’s article “Quantum minds” (3 September, p 34). The observation that our decision-making processes resemble quantum mathematics is interesting. However, Buchanan pulls back from even the vaguest suggestion that the brain might be a quantum-mechanical machine.
Researchers have been studying quantum biology for years. It is clear that nature is ahead of the game in applying physics to biology without needing to understand how it works. There is no reason why quantum physics should be any different.
Why wouldn’t biological matter be utilising quantum processes, just as it used gravity before Isaac Newton discovered it and detected electromagnetic radiation with the eye before James Maxwell had written his equations.
Theoretical physics presents ever more esoteric models of our universe with multiple dimensions, multiverses and so on. Perhaps our biology is already well aware of these and is an active participant in whatever is the “true” nature of the universe. Our minds could even be a part of that, as yet unseen, reality.
From Lucien Howe
In the world of strong AI – artificial intelligence that matches or exceeds human intelligence – the idea of the quantum playing a part in the mind has been around at least since the publication of Roger Penrose’s book The Emperor’s New Mind in 1989.
It is clear quantum mechanics plays a direct role in human cognition – in fact I would go so far as to say that sentience is almost impossible without it.
Haltwhistle, Northumberland, UK
The editor writes:
• Look out for our article on quantum biology next week.
Sunshade shadow
Your article on an upcoming field test for engineering the climate with atmospheric aerosols (10 September, p 8) and the editorial defending such trials (p 3) give ammunition to critics of such work. These trials might make the public more complacent about climate change and less willing to be inconvenienced to deal with it.
What’s more, screening out some of the sun’s rays with aerosols does nothing about the problem of ocean acidification. In fact, although the article points out that the proposed aerosol if this technique is applied would be sulphate, it fails to mention that this is a pollutant and would increase ocean acidification.
From David Chapman
It seems clear that climatologists do not fully understand how the climate works. To start geoengineering such a delicate and unpredictable system is the height of folly.
One cannot predict damaging side effects, which may be favourable to some people and seriously damaging to others. At the moment we attribute destructive weather to natural processes. Once someone intervenes in these systems, responsibility may fall on them for further unusual and unwelcome phenomena.
Worthing, West Sussex, UK
Concussion's impact
Your feature on the harmful consequences of concussion suggests an unexplained cellular “domino effect” is involved (10 September, p 38). The process starts when a damaged cell leaks something that causes a neighbouring cell to die and leak more of that something, and so on.
There is much evidence that the something is unliganded iron – iron separated from the molecule it is normally bound to. There is also evidence it becomes more toxic when it binds to tau proteins. I have summarised these issues in an open-access paper in .
Nuclear nasties
As Allison Macfarlane articulates, nations that have nuclear power must also have an operational plan for long-term storage and disposal of high and intermediate-level waste (27 August, p 26).
At last the UK is addressing this. Since 2008 the policy has been to develop a geological disposal facility (GDF), and volunteer communities are being sought. So far, there are interested parties in west Cumbria, an area with nuclear facilities that are major employers, such as Sellafield.
The UK has an exceptional range of geology but it is an island with limited space and a public deeply suspicious of anything nuclear. Optimum geological and political solutions are unlikely to coincide.
A robust safety case will aid the search for a suitable site, and universities are poised to contribute to the research effort needed to develop one. At the University of Manchester, funded by an endowment from the former British Nuclear Fuels, the Research Centre for Radwaste and Decommissioning has been established to meet the challenges. The nuclear industry in the UK failed in 1997 to obtain planning permission to develop a deep geological test laboratory in Cumbria, with the paucity of research in certain areas a major factor for the failure. It is still paying the price.
Constructing a robust, comprehensive safety case for a GDF is a real challenge when planning for a million years. It will require a major collaboration between industry and academia, overseen by a management group with the single objective of fulfilling the UK’s needs: safe and secure geological disposal of our nuclear legacy.
From James Sandeman
Macfarlane warns of the lack of progress in finding and proving the suitability of safe dump sites for spent nuclear fuel, with an emphasis on underground repositories. Other commentators extol the virtues of “plasma vitrification” as the magic wand to turn all sorts of toxins into harmless fluffy white clouds and useful inert glass bricks.
To the layman this sounds too good to be true. Is it?
Glasgow, UK
The editor writes:
• Vitrification of high-level waste – locking it into a special glass – is done as part of the reprocessing of spent fuel. If you are not going to reprocess fuel rods, there is little need to vitrify them, unless you enjoy spending money for no reason. Vitrified high-level waste would still need to be buried in a repository.
Ethical steak
Your valuable editorial “Credible or inedible” (3 September, p 5) needs some clarification: PETA is not backing the laboratory production of in vitro meat to allow vegetarians to “tuck in with a clear conscience”, but to provide a source of ethically obtained meat for meat-eaters. They, like smokers trying to quit tobacco, find it very hard to give up the stuff despite ethical, health and environmental reasons to do so.
Regarding the “yuck factor”, it is hard to imagine that in vitro meat, which is real meat grown in an environment free of E. coli, Campylobacter and so on, could top the yuckiness of the slaughterhouse.
Decay to stay
I was taken aback by the suggestion that the discovery of a gene linked to tooth enamel production could lead to the reactivation of enamel-producing cells to avoid decay (28 May, p 17).
When a tooth is developing, ameloblast cells are responsible for enamel formation, but they die once this process is complete, before the tooth erupts into the mouth. By the time the tooth emerges, it no longer has any ameloblasts covering it, and the enamel is a non-living piece of hard tissue.
Hence, it is impossible to reactivate such enamel production, as the ameloblasts are no longer there.
Dawkins on altruism
Contrary to Sebastian Hayes’s letter (10 September, p 32), from its second edition onwards Richard Dawkins’s The Selfish Gene has a chapter about altruism as an important part of evolution. Dawkins takes the position that genes are “selfish” in the sense that their only concern is replication, not that they make their carriers selfish.
I strongly agree with Hayes about the current complete misunderstanding of evolution, but it seems a bit unfair to blame Dawkins simply because many of the perverters of evolutionary theory namecheck a book they have clearly never read, and pervert its theory too.
In black and white
In “Racial grant gap” (27 August, p 5), you report that “black scientists receive 10 per cent fewer funding awards than would be expected if race were not an issue”. While true, the numbers also show white scientists receive awards nearly twice as often as black scientists – a more damning figure. Percentages can be misleading.
Penguin pique
I was intrigued to learn that the body temperature of king penguin chicks falls when they are fed cold meals (20 August, p 16). How often do they get hot ones?
Biever away
Celeste Biever can take heart after not completing the ultimate intelligence test (10 September, p 42). Knowing when to give up on a frustrating task is in itself a fair test of intelligence.
Boarding pass
Astrophysicist Jason Steffen’s optimal method for boarding an aircraft in alternate rows (10 September, p 14) is a great idea and should be implemented by all airlines immediately.
The disembarking bottleneck could be avoided by allowing able-bodied passengers to use the emergency exits and slides. This would have the added benefit of testing the slides more frequently.
For the record
• In the story on oil supplies (27 August, p 4), Libya’s 2009 output should have been 2.4 million barrels a day
• Researcher José Hernández-Orallo, quoted in the feature on a universal intelligence test (10 September, p 42), is from Technical University of Valencia, Spain