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Jumbo's blind spot
See newscientist.com for letters on: ● Imperfect pitch ● Black holes postponed ● A painless electrocution
The article that Pinnock points to in his letter is authored by a team whose members disclose potential conflicts of interest arising from work for leading pharmaceutical giants, including Wyeth, GlaxoSmithKline and Eli Lilly. Pinnock himself held a senior post at Pfizer. The lives of children and young people are too precious to be left at the mercy of corporate good faith. We need evidence from researchers for whom there can be no conflicts of interest. London, UK
Jumbo’s blind spot From Jim Franks Various experiments are being mounted, at some expense, to try to find ways of keeping elephants in Africa off farmers’ crops (13 October, p 5). Among notes from my days in soil engineering, I have the paper “The uselessness of elephants in compacting fill” by R. L. Meehan, in the August 1967 Canadian Geotechnical Journal. A footnote states: “Elephants ‘see’ the ground by feeling with the trunk and have a blind spot which is out of the normal range of both eyes and trunk. The animals may be kept out of gardens by stringing a wire horizontally 2 metres above ground. They are able to feel the wire, but cannot evaluate this invisible barrier and retreat in confusion.” Perhaps the solution to the elephant problem is already known by African farmers. Aviemore, Highland, UK
Just in time From Simon Bennett Marcus Chown proposes a second time dimension (13 October, p 36), but he gives no real indication of how this might work or its implications, beyond resolving some problems in string theory and grand unified theories. It is not clear to me why an object moving through a second www.newscientist.com
time dimension – call it t' – should be able to travel backwards in normal time, t, just because it is no longer travelling along the t axis, like some object plucked from the x-y plane in Flatland and deposited elsewhere in the plane, having been moved through z. It seems to assume that what we perceive as time is parallel to the t axis with some constant value of t' , possibly zero, rather than being a vector with components in t and t', and that moving away from this axis somehow overcomes the monotonic nature of time as we experience it. Could t' explain the relativistic time dilation effect? May objects accelerating towards the speed of light still travel forwards in hypertime at a constant rate, the t' component increasing and the t component decreasing, while these stay the same for the stationary observer? In an article in an earlier issue, Saswato Das wrote that cryptographers expect to stay ahead of the quantum codebreakers by using techniques such as hash chains that “require you to wait to calculate one thing before you calculate another” (15 September, p 30). What if quantum computers can operate in multiple time dimensions, so that one calculation can take place at the same time as another in t but before it in t' ? Leicester, UK
Many worlds, one wave From Adrian Smith A glaring anomaly strikes me in David Deutsch’s new work on the many-worlds interpretation of quantum mechanics, which you reported on 22 September (p 6).
How to Fossilise Your Hamster
The original many-worlds interpretation was a response to the Copenhagen interpretation of the double-slit experiment, in which single photons apparently go two ways round the apparatus. This conundrum was avoided by proposing that each path is in a different, parallel world. But how then do we get the interference of the two waveforms, now in different universes? The only plausible get-out clause is to have the parallel universes briefly interfere with each other. But this appears to run counter to the many-worlds view, which was designed to have a determinate universe for each world-line or history. Salvation is at hand, however, since there is one view of quantum mechanics which has no anomalies: that there is no real particle, only a wave packet. The particle is only an expression to signify the point at which a wave packet interacts with our apparatus. One wave packet can interact only once, giving the impression of one particle. Addingham, West Yorkshire, UK
Stemming snake oil From Doug Cross There is a perfectly simple remedy in Europe to prevent firms selling “homeopathic CDs” or similar products claiming to cure medical complaints (13 October, p 4). The 2004 European Union Medicines Directive prohibits advertising or selling any substances claiming to have medicinal properties unless they have a valid medicinal licence. In the UK, refer advertisements for snake oil to your local trading standards officers, who have the
The latest collection from New Scientist featuring experiments for armchair scientists
Available from booksellers and at www.newscientist.com/hamster
power to seize such goods and prosecute the seller or advertiser. Lowick Bridge, Cumbria, UK
Is this a question? From Lucian McLellan Concerning free will (letters since 25 August), the 1986 University of Bristol philosophy degree final exam included the optional question 16: “Could you have not answered this question?” I was raised on the urban legend of the Eton College entrance exam candidate who answered “What is courage?” with the words “This is”. Therefore, though my degree rested on it, I was hugely tempted to hand in a sheet of paper that was blank, except for the number “16” in the margin. I didn’t. QED? Bristol, UK
For the record ● Our report about photonic crystals (28 July, p 28) should have attributed their properties to an array of microspheres, not of atoms. ● We wrote: “Even in eastern Europe abortion rates have halved from 90 abortions per 1000 women in 2005, to 44 per 1000 in 2003” (20 October, p 8) That should have been “90 abortions per 1000 women in 1995…”. Letters should be sent to: Letters to the Editor, New Scientist, 84 Theobald’s Road, London WC1X 8NS Fax: +44 (0) 20 7611 1280 Email: [email protected] Include your full postal address and telephone number, and a reference (issue, page number, title) to articles. We reserve the right to edit letters. Reed Business Information reserves the right to use any submissions sent to the letters column of New Scientist magazine, in any other format.
10 November 2007 | NewScientist | 27
The article that Pinnock points to in his letter is authored by a team whose members disclose potential conflicts of interest arising from work for leading pharmaceutical giants, including Wyeth, GlaxoSmithKline and Eli Lilly. Pinnock himself held a senior post at Pfizer. The lives of children and young people are too precious to be left at the mercy of corporate good faith. We need evidence from researchers for whom there can be no conflicts of interest. London, UK
Jumbo’s blind spot From Jim Franks Various experiments are being mounted, at some expense, to try to find ways of keeping elephants in Africa off farmers’ crops (13 October, p 5). Among notes from my days in soil engineering, I have the paper “The uselessness of elephants in compacting fill” by R. L. Meehan, in the August 1967 Canadian Geotechnical Journal. A footnote states: “Elephants ‘see’ the ground by feeling with the trunk and have a blind spot which is out of the normal range of both eyes and trunk. The animals may be kept out of gardens by stringing a wire horizontally 2 metres above ground. They are able to feel the wire, but cannot evaluate this invisible barrier and retreat in confusion.” Perhaps the solution to the elephant problem is already known by African farmers. Aviemore, Highland, UK
Just in time From Simon Bennett Marcus Chown proposes a second time dimension (13 October, p 36), but he gives no real indication of how this might work or its implications, beyond resolving some problems in string theory and grand unified theories. It is not clear to me why an object moving through a second www.newscientist.com
time dimension – call it t' – should be able to travel backwards in normal time, t, just because it is no longer travelling along the t axis, like some object plucked from the x-y plane in Flatland and deposited elsewhere in the plane, having been moved through z. It seems to assume that what we perceive as time is parallel to the t axis with some constant value of t' , possibly zero, rather than being a vector with components in t and t', and that moving away from this axis somehow overcomes the monotonic nature of time as we experience it. Could t' explain the relativistic time dilation effect? May objects accelerating towards the speed of light still travel forwards in hypertime at a constant rate, the t' component increasing and the t component decreasing, while these stay the same for the stationary observer? In an article in an earlier issue, Saswato Das wrote that cryptographers expect to stay ahead of the quantum codebreakers by using techniques such as hash chains that “require you to wait to calculate one thing before you calculate another” (15 September, p 30). What if quantum computers can operate in multiple time dimensions, so that one calculation can take place at the same time as another in t but before it in t' ? Leicester, UK
Many worlds, one wave From Adrian Smith A glaring anomaly strikes me in David Deutsch’s new work on the many-worlds interpretation of quantum mechanics, which you reported on 22 September (p 6).
How to Fossilise Your Hamster
The original many-worlds interpretation was a response to the Copenhagen interpretation of the double-slit experiment, in which single photons apparently go two ways round the apparatus. This conundrum was avoided by proposing that each path is in a different, parallel world. But how then do we get the interference of the two waveforms, now in different universes? The only plausible get-out clause is to have the parallel universes briefly interfere with each other. But this appears to run counter to the many-worlds view, which was designed to have a determinate universe for each world-line or history. Salvation is at hand, however, since there is one view of quantum mechanics which has no anomalies: that there is no real particle, only a wave packet. The particle is only an expression to signify the point at which a wave packet interacts with our apparatus. One wave packet can interact only once, giving the impression of one particle. Addingham, West Yorkshire, UK
Stemming snake oil From Doug Cross There is a perfectly simple remedy in Europe to prevent firms selling “homeopathic CDs” or similar products claiming to cure medical complaints (13 October, p 4). The 2004 European Union Medicines Directive prohibits advertising or selling any substances claiming to have medicinal properties unless they have a valid medicinal licence. In the UK, refer advertisements for snake oil to your local trading standards officers, who have the
The latest collection from New Scientist featuring experiments for armchair scientists
Available from booksellers and at www.newscientist.com/hamster
power to seize such goods and prosecute the seller or advertiser. Lowick Bridge, Cumbria, UK
Is this a question? From Lucian McLellan Concerning free will (letters since 25 August), the 1986 University of Bristol philosophy degree final exam included the optional question 16: “Could you have not answered this question?” I was raised on the urban legend of the Eton College entrance exam candidate who answered “What is courage?” with the words “This is”. Therefore, though my degree rested on it, I was hugely tempted to hand in a sheet of paper that was blank, except for the number “16” in the margin. I didn’t. QED? Bristol, UK
For the record ● Our report about photonic crystals (28 July, p 28) should have attributed their properties to an array of microspheres, not of atoms. ● We wrote: “Even in eastern Europe abortion rates have halved from 90 abortions per 1000 women in 2005, to 44 per 1000 in 2003” (20 October, p 8) That should have been “90 abortions per 1000 women in 1995…”. Letters should be sent to: Letters to the Editor, New Scientist, 84 Theobald’s Road, London WC1X 8NS Fax: +44 (0) 20 7611 1280 Email: [email protected] Include your full postal address and telephone number, and a reference (issue, page number, title) to articles. We reserve the right to edit letters. Reed Business Information reserves the right to use any submissions sent to the letters column of New Scientist magazine, in any other format.
10 November 2007 | NewScientist | 27