Vacuum starship
One aspect of the research of myself and Robert Forward on the quantum vacuum starship was omitted in your interesting article (24 May, p 20). In principle it is possible to operate the starship using energy extracted from the quantum vacuum itself.
Thus the operation of the entire spacecraft is based on properties of the quantum vacuum. The energy is extracted from the vacuum by using the Casimir force between two parallel uncharged plates. This force arises because quantum fluctuations with wavelengths longer than the separation between the plates are excluded from the gap, resulting in a net attractive force between the plates.
As the plates approach each other, the energy from the Casimir force is used, for example, to wind a spring that drives a motor that oscillates one of the plates slightly. This prevents the plates from touching, because once this happens you cannot extract any more energy.
For details, see the article at
Placebo effects
I was fascinated by Feedback’s piece on drugs having side effects the same as the symptoms that they are supposed to fix (31 May). My suspicious mind wonders whether the drug companies are surreptitiously trying to cash in on the placebo effect to make up for the uselessness of their pills. If the placebo effect doesn’t get rid of the symptoms, they must be a “side effect” of the “drug”.
Letter
Side effect lists are compiled from reports from patients taking the medicine for the particular condition. If the medicine is not fully effective, or if the disease state itself gets worse, then the vomiting, itch, diarrhoea or whatever will continue, or worsen, and this may well be reported as a side effect, even though it is simply the disease expressing itself.
In addition, just about any drug is capable of irritating the digestive system or producing a skin reaction, hence the almost inevitable addition of nausea, diarrhoea and skin rash to the list of side effects.
For the record
鈥� Washington Diary (31 May, p 53) stated that “about 5 per cent” of Iraq’s marshlands are “dried up”, having been drained by Saddam Hussein. This was something of an understatement, as it should have read “all but 5 per cent”.
鈥� Our special report on ancestral bones (31 May, p 12) repeatedly referred to these bones as “artefacts”. As they are human remains, not human handiwork, this was clearly incorrect.
鈥� The Insider article on public sector research (31 May, p 54) should have stated that the brain cancer drug temozolomide was licensed by Cancer Research Technology on behalf of Cancer Research UK (not Wellcome, as stated).
鈥� The box in the article on the geology of Everest (31 May, p 14) refers to the Hillary step as being on the North Ridge. It is in fact on the South East Ridge.
BSE and the US
Debora MacKenzie makes claims about US efforts to prevent bovine spongiform encephalopathy, despite the fact that no evidence of BSE has ever been found in the US (31 May, p 6).
Since 1989, the US Department of Agriculture’s Animal and Plant Health Inspection Service has put in place numerous safeguards to prevent BSE from entering the US. These safeguards include stringent import requirements and BSE surveillance levels that far exceed international standards.
In the fiscal year 2002, the US tested more than 19,900 “high-risk” cattle. Experience from Europe confirms that testing non-ambulatory cattle and cattle that show signs of central nervous distress is the best way to discover whether BSE is present. At our current surveillance level, we would detect BSE at a rate of one case per million head of cattle.
In addition to targeted surveillance efforts, the US prohibits the use of most mammalian protein in the manufacture of animal feeds given to ruminants. This feed ban effectively addresses the way scientists believe BSE is spread. The US is one of only a few countries that have imposed a feed ban despite having no recorded BSE.
An independent risk assessment by Harvard University in 2001 confirmed that the US is taking all the necessary and appropriate actions to prevent BSE. The assessment showed that the risk of BSE occurring in the US is extremely low. The report recognised that the early protection systems put into place by the Department of Agriculture and the Department of Health and Human Services have been largely responsible for keeping BSE out of the US and would prevent it from spreading if it ever did enter the country.
Letter
Since the early 1990s we have been assured that adequate safeguards and monitoring are in place to prevent a BSE outbreak in US cattle.
In the 17 May, US edition of New 杏吧原创, I noticed a US Department of Agriculture advertisement for “Prion 杏吧原创s”, with a deadline for applications within 10 days. One cannot help but wonder at the need to advertise, and at such haste.
Gene choice
On the matter of genetically modified foods, you report that US trade representative Robert Zoellick criticises the present European Union ban because the US believes “consumers have the right to make their own decisions about what to buy” (24 May, p 5).
Is this the same US that objects to the labelling of GM foods 鈥� the very labelling that would enable consumers to make their own decisions? Am I missing something, or does the US administration need to do some more joined-up thinking?
Pretend we're free
As interesting as your latest specials on free will have been, it’s hard to shake off the feeling that the question itself is pretty irrelevant (17 May, p 33).
Either we have free will, in which case it’s business as usual, or we don’t. If we don’t, we must have a mere illusion of free will. But as we can’t break free from that (as we’d still be following the chain of events that goes back to the start of the universe), we might as well pretend we have free will anyway, as we’ll probably live happier, fuller lives, blissfully unaware that we don’t have control. Simple as that.
Letter
A criminal’s defence that “my brain made me do it” (24 May, p 38) could be a whole lot worse than admitting “I’ve been a naughty boy” because taking free will out of the equation doesn’t take away the risk to society.
Our law exists to punish, of course, but it’s also there to keep undesirables away from law-abiding citizens. Your “naughty” murderer who admits guilt might make it out of his cell in 12 years or so, and he has the memory of day-to-day life in a box to keep him from re-offending.
But stuck with the “brain” defence, you’re in it for the duration. You’ll never get out of the asylum because your brain made you do it and you can’t control whether it’ll happen again. There can’t be any rehabilitation, because you have no control, and I’m afraid society won’t let people like you stalk among the rest of us. It’s best just to own up to being a naughty boy.
Technohominids
Now that it is no longer possible to cite language as the defining difference between Homo sapiens and H. neanderthalensis, the enquiry becomes more esoteric, as exemplified in Steven Mithen’s fascinating article (17 May, p 40).
It was, of course, natural for linguistic thinkers to assume that their particular mode of reasoning was crucial, but our technological history indicates otherwise. For them I propose a simple experiment: describe in words an abstract three-dimensional form that you have never seen before without forming an image of it in the mind’s eye first. We are distinguished from other creatures not by what we have said but by what we have made. The Neanderthals’ ability to reason visually was clearly inferior to ours. So it was us who developed superior technologies and took over the world.
I knew a cabinet maker who could neither speak nor hear, but had complete command of 3D form: working drawings showed all he needed to know. Some 70 per cent of the content of the human mind is visual, leaving 30 per cent to be shared between aural, verbal, tactile, motor, taste and smell.
It has been recorded that listening to Mozart raises the IQ and that the effect persists for half an hour after the music stops. There must be similar effects from the other arts, helping to explain why they are felt to be of value. Composers think aurally, writers verbally, artists and designers visually. With pure visual reasoning, any verbal thought is an interruption, an intrusion, a nuisance.
You cannot talk an axe, a bow, a shelter into existence, you can only talk about it after it already exists as a vision in the mind. Likewise with every development and modification.
It is no coincidence that our ancestors were master draughtsmen on cave walls and made sculptures and ornaments. Real visual art expresses the essence of being human, the unique designing animal with the faculty of visual reasoning 鈥� and hands, of course.
Letter
With regard to the repatriation of Australian Aboriginal human remains in British institutions, there is one very important further consideration that is usually neglected. The return of most of the material will be beneficial to non-Aboriginal Australians as well.
There is a process of reconciliation at work in Australia that needs this kind of action if it is not to falter in the early stages. In 2000, hundreds of thousands of Sydneysiders marched across the harbour bridge in the name of reconciliation. Then Cathy Freeman lit the Olympic flame and won a gold medal, and millions of us wept with joy. It all looked so positive, provided these gestures translated into real change.
Aboriginal people in Australia are still generally granted a low level of access to the Australian present and so their right to limit the access of us “whitefellas” to their past must be respected, or at least understood. That we non-Aboriginal scientists must share that burden is only fair (and the work of many scientists in the past is in itself part of the problem).
Keep the bones
In your editorial on the value of skeletal collections in the UK you say that anthropology has not done enough to shake off its western elitist tradition (31 May, p 5).
It is hard to see the basis for this statement. As a whole, anthropology has probably done more than any other stream of intellectual thought to place non-western cultures on an equal footing with western ones. Indeed, it is one of the rationales of the subject.
Scientifically, anthropology has played a major role (including, significantly enough, through the study of skeletal remains) in removing the scientific basis for racism, in showing the unity of the human species, and in mapping its evolution and history globally, rather than just as a European story.
In the context of rapidly developing scientific technologies, as well as changing questions, repatriation of skeletal remains without safeguards would limit and damage the contribution that anthropology can make towards an understanding of humans, both scientifically and culturally.
Repatriation 鈥� which in the recent past has often meant destruction and reburial, and placing remains, some of them thousands of years old, beyond science and anthropology 鈥� is equivalent to destroying books because they should only be read by certain people, or saying that we no longer need the texts of Shakespeare because all the research has been done.