War on drugs
Everyone who has studied the science and history of marijuana use agrees that prohibition does more harm than good and should end. The votes to legalise it in the states of Colorado and Washington (17 November 2012, p 6) are great steps towards a more rational policy for the US and the rest of the world, given most countries will follow its lead.
The war on drugs has been an abject failure to learn from the prohibition of alcohol. Ending it would free up the equivalent of about $100 billion per year of resources for productive uses and save thousands of people who are currently criminalised from the resulting needless exclusion from the job market.
From David Marjot, psychiatrist
That alcohol and tobacco cause damage equivalent to that of heroin and cocaine , as the prohibition of drugs is justified by the harm they cause. Supplying anyone with alcohol or tobacco is then morally no better or worse than giving them heroin or cocaine. Do not confuse morality, legality and respectability.
It is shocking to sentence a person to imprisonment for drug offences that cannot be morally distinguished from similar acts that are unpunished, even rewarded. We cannot avoid the conclusion that those subjected to sanctions for drug supply and use are a persecuted minority.
Big problem?
While engineers continue to be surprised by the endurance of Moore’s Law, which says that computing power doubles roughly every 18 months, we can be certain that Silas Beane’s descendants will never get to simulate the universe on a lattice resolution of 10-27 metres (15 December 2012, p 33).
Today’s state-of-the-art memory chips use transistors a little larger than 10 nanometres (10-9 metres) across. When Beane extrapolates Moore’s Law over 500 years, he is implying transistors will continue to shrink to impractical sub-nuclear, quantum-scale dimensions.
But even if that engineering fantasy were to come true, it would defeat the purpose. The envisaged grid-based simulation involves calculating how physical properties change from one instant to another at every point in the model. You need physical memory to store the data. The circuits used to hold all the data for a universe whose points are 10-27 metres apart could not themselves fit into the universe being modelled.
It's a trap
If Harold de Vladar is right that game theory can help define the risk of signalling extraterrestrials, one wonders if all attempts at contact are suicidal (15 December 2012, p 11). Unless an alien civilisation is just a few centuries ahead of us technically – unlikely given the age of the universe – on receipt of our missive they will know that our capability is way below theirs. Fine if they are benign, but not if hostile.
For the same reason, we should surely ignore any communication we get because it is likely to be a trap. If only one such hostile civilisation exists they will likely have conquered or destroyed any other who has in the past sent speculative communications. The only communications that will endure are the hostile traps.
Right decision
Further to your look at the vote against mandatory labelling of genetically modified food in California (17 November 2012, p 28), nothing Californians eat is natural. The defeated proposal, known as Prop 37, was another attempt by practitioners of the politics of fear to codify a false dichotomy in our labelling regulations. RIP Prop 37.
Crunch crunched
“This book will anger many environmentalists,” says Fred Pearce in his careful review of Dieter Helm’s The Carbon Crunch (17 November 2012, p 51). It would be more accurate to say that the book will anger anyone with logic, as its arguments are nonsensical.
Helm says that existing clean energy technology is expensive, uneconomic and largely ineffective. But he presents no quantitative analysis to justify this. Onshore wind turbines are already competitive with conventional energy sources in a growing number of markets, at around 9 pence per kilowatt hour.
Secondly, he says that coal is the major culprit and that shale gas will enable us to replace it. But even if we switched all coal electricity to gas, we would only reduce carbon dioxide emissions by about 5 gigatonnes per year, 15 per cent of the total from humans.
Using compressed natural gas to power vehicles, as he advocates, only saves about 10 per cent, according to a study by the US Department of Energy’s Argonne National Laboratory.
This is not nearly enough to stop dangerous climate change. The only way to reduce emissions fast enough is to first decarbonise electricity and then electrify vehicles and heating. Even without carbon-free electricity, the latter steps reduce emissions in those sectors by 50 per cent.
Helm holds out research and design as the answer, after shale. But solar and wind are by far the most abundant energy sources, and current technologies are already close to their thermodynamic limits. The best way to reduce costs further is through mass production and widespread deployment.
Ancient sunshade?
You reported research suggesting that Earth might once have had a planetary ring, like Saturn (8 December 2012, p 18).
Is it possible that major meteorite impacts on the moon produced such a ring of debris? If so, could the effect on climate have caused the “snowball Earth” events about 2.3 billion years ago?
Collateral damage
The rise of small personal drones brings many issues (8 December 2012, p 42), including for wildlife. I fear that birds in areas where drones will be used could be in for a tough time, especially in war zones, where they might be shot down by mistake.
Delta debate
Regarding the article on flood risks for the world’s deltas, there are some further factors worth raising as they help mitigate subsidence (1 December 2012, p 40). First, Holocene sediments in some deltas include sandy layers – as in Bangladesh – which provide aquifers but do not create subsidence by compaction when the water is removed.
Then there is the possibility of carrying out controlled tidal sedimentation to compensate for subsidence, a process known as warping. It was once practised in England and is now being tried in parts of Bangladesh.
Finally, conditions in deltas tend to be heterogeneous, making it unsafe to generalise. On the Ganges tidal floodplain, for example, subsidence rates apparently range between 0 and 5 millimetres per year; and the high rates the article quotes for Bangkok probably apply only to parts of the city, not to the whole of the Chao Phraya delta.
We can fix it
MacGregor Campbell need not worry about the manufacturer of his kettle claiming copyright when he prints a new handle (15 December 2012, p 46).
They are more likely to be concerned that the kettle’s planned obsolescence has been foiled. They would prefer Campbell to buy a new kettle.
Diagnosis disorder
Your editorial discusses the American Psychiatric Association’s failure to agree a new system of diagnosing personality disorders for the next edition of its handbook, DSM-5 (8 December 2012, p 5).
While improving the system would help to ensure that the correct diagnosis is given, the problem of inadequate availability of psychotherapy has not gone away.
In the UK’s National Health Service, for example, there are insufficient psychotherapists with training and experience of the treatment of personality disorders. There is also the issue of stigma. Some patients might prefer to stick with a wrong diagnosis for this reason.
Early roller coaster
The inventors of a new train in Japan were not the first to think of gravity-aided public transport (8 December 2012, p 22). At least some London Underground lines have stations higher than the tracks either side, so that gravity helps to slow the trains’ approach and accelerate them as they leave. Clever people, those Victorians.
Winter warmer
I was surprised there was no reference to the Gulf Stream in your look at possible climate change in Europe by 2050 (1 December 2012, p 8). It clearly has considerable influence on the UK’s climate, and I seem to remember an article some years ago discussing the possibility of it ceasing completely.
• The models used to predict European temperatures do take account of such factors. However, while there are still concerns about the Gulf Stream weakening, it currently seems like it would happen too far in the future to be a significant factor in 2050.
See what I mean?
Richard Price’s letter decrying the description of a voltage in terms of that generated by AA batteries rather than SI units (8 December 2012, p 32) reminded me of how Richard Feynman tried to make physics understandable. He used many figures of speech to help us visualise things.
In his book What Do You Care What Other People Think? he recalled a moment of inspiration when his father was reading from the Encyclopaedia Britannica: “[Tyrannosaurus rex] is 25 feet high and 6 feet across.” Feynman went on to explain: “My father would stop reading and say ‘…that would mean that if he stood in our front yard, he would be tall enough to put his head through the window here… but his head would be too wide to fit in the window.'”
I’m all for making our arbitrary system of scientific units easier to understand.
For the record
• In our look at the mystery of matter (5 January, p 36), artwork should have been credited to Daniel Stolle.