Green graphene?
Katharine Sanderson sets out the wondrous potential of new 2D materials such as graphene (25 October, p 40). Like all good things, however, there may be a downside overlooked in the excitement of discovery.
A key property of graphene is its high strength and, presumably, durability. So what are the likely consequences of a world suddenly awash with stuff made from these new materials? I trust that, this time, someone considers the recyclability and end-of-life issues for each new material before it becomes a problem and not afterwards. But I’m not holding my breath.
Mold, Clwyd, UK
For the record
鈥� Our claim about a burst water main near Singapore’s Marina Bay Sands didn’t hold water; the leak was several hundred metres away and was spotted before it could threaten the complex (8 November, p 20).
Don't panic
The universe modelled by Howard Wiseman and his colleagues uses 41 worlds including ours. But that was the minimum number needed to get a qualitatively similar result to the double-slit experiment, so 42 would work too.
Don't panic
I was fascinated by Michael Slezak’s article describing a new take on the many worlds theory for explaining quantum mechanics (8 November, p 6), particularly as the theory predicts that as few as 41 other universes existing alongside ours could explain these effects. Is it possible that the answer to “Life, the Universe and Everything” is 42, as Douglas Adams knew all along?
Verwood, Dorset, UK
Smoke signals
It’s easy to find out if e-cigarettes help you quit or get you hooked (1 November, p 35). Just ask the tobacco companies if they are for or against them.
Berlin, Germany
Full of beans
In her guide to the human mind, Caroline Williams recommends caffeine to shake off sleep inertia in the mornings (4 October, p 34).
This advice is worthless as any studies supporting her contention were inevitably carried out on caffeine addicts. I gave up caffeine 26 years ago and I am fully awake every morning if I go to bed early enough. Caffeine is a useless and damaging addition to human life. Like all recreational drugs, the only people who need them are those who take them.
快猫短视频 should not promote addiction to anything, and especially something that tastes so disgusting. It’s time to get the drugs out of our system.
Glengarriff, Cork, Ireland
Moral code
In Jacob Aron’s article on hybrid computers, Chris Eliasmith says that neural networks are required “if you want to build a computer that is cognitive in the way we are” (1 November, p 21).
But do we? I’m with Elon Musk in thinking that fundamental questions like this need to be asked and the answers debated before we go too far down this road.
Humans with different belief systems are bad enough at getting on with each other, especially with the limited resources our little globe can provide. Throwing a naive but globally networked “alien” awareness into the mix will have unintended consequences. What belief system will it be programmed with? At the very least we need a robust, internationally agreed framework within which to move forward.
Darlinghurst, New South Wales, Australia
Dark side of research
In your article on decoding brain signals (1 November, p 8), the scientists report that they have followed their work on reading these impulses by “turning their hand to predicting what songs a person is listening to by playing lots of Pink Floyd to volunteers”. Is this ethical?
Hampton, Middlesex, UK
Against the herd
Regarding the 2008 global market crash, the Queen may well have asked “why did nobody notice it?” (1 November, p 28). But she was wrong, some people did.
Many were laughed at and some quietly got ready for it. Gregory Zuckerman’s book The Greatest Trade Ever gives a wonderful account of how John Paulson saw it coming and made $20 billion betting against the markets.
It is not in the interests of people who see crashes coming to say anything, because they are either ridiculed, or in the case of people like Paulson, stand to gain a great deal of money if their predictions pay off.
Kimberley, Nottinghamshire, UK
Quantum computing
The world of quantum computing is complex, and while we appreciate Michael Brooks educating audiences on the various efforts, there were some misconceptions made about the D-Wave system in his article (18 October, p 43).
In particular, the article’s table “Which quantum computer is right for you?” indicates that the D-Wave machine is only suitable for optimisation 鈥� finding the best solution to a given problem 鈥� and cannot perform other computations such as integer factorisation.
In fact, our machine has been used to perform optimisation, sampling, machine learning and constraint satisfaction. Although our machine cannot run Shor’s algorithm, it has factorised integers tens of thousands of times larger than the integers factored by any other quantum computer currently available.
We were also given the lowest score on your “quantumness” category despite the fact that we recently published a peer reviewed paper (Physical Review X, ) demonstrating a world record for the number of superconducting qubits entangled. It was said that we cannot perform error correction, when, in fact, we can.
Finally, suggesting that the other quantum computers are all “easier to use” than our computer is a significant stretch. Our machines come with an interface that allows them to be programmed in Python, MATLAB, or C++ from any internet-connected computer in the world, and our users have harnessed this interface to demonstrate by far the widest range of applications yet achieved on any type of quantum computer.
Although quantum computing is still in its infancy, D-Wave has been a leader in the field, driving forward innovation on a scale that most said was impossible. Our technology is being used by commercial customers today 鈥� something that cannot be said about any of the other efforts reflected on in the article.
Vancouver, Canada
Hard to swallow
You report that banded stilts tracked by GPS tags were found to fly 2200 kilometres in two days (1 November, p 18). That’s crazy. Did anyone sit down and calculate average velocities of these birds?
Foxboro, Massachusetts, US
Fuelling growth?
Although we are blessed in New Zealand with an abundance of renewable resources, these are not enough for our country of just 4 million. I work at a large electricity company in New Zealand. Our energy portfolio is mostly hydroelectric and geothermal. But we also burn natural gas and the odd bit of coal.
Almost all “green energy” articles look towards renewable resources such as solar and wind. But electricity must be supplied to match the demand of each moment. Being unable to meet this demand would spell economic disaster.
On a cold, still winter’s morning, wind and solar need to be backed up by a complementary source such as coal or gas. But nobody wants to own or run coal and gas generators if they can only make money out of them for a few hours on a few days.
This prompts the much-feared nuclear option. Not only are politicians afraid to mention it, but so are many in the scientific sphere, even though statistically it is probably the least lethal form of large-scale power generation.
In terms of safety, we are still using 1960s technologies for our nuclear plants. If the aviation industry was similarly “advanced”, we would still be flying propeller aircraft.
There is a lot to do. Molten salt reactors have to be evaluated, and possibly built and tested. The thorium promise needs to be looked at. The terrible inefficiency of uranium and radioactive waste needs to be looked at.
However, the most immediate need is for people of intelligence to look honestly at the future, our economies and our energy-demand life cycles and bring facts into the public sphere.
Auckland, New Zealand
Fuelling growth?
Imagining a world without fossil fuels, Michael Le Page fails to mention that without them, there is no way modern intensive agriculture could have developed (18 October, p 34).
Think of diesel for tractors, combines and distribution trucks, electricity for cold stores, and petroleum-derived agrochemicals. Without those things, we could not have huge modern cities nor the world population we currently enjoy.
Quite how massive industrial farms and food production and distribution systems will be able to cut their carbon emissions by 80 per cent, I do not know. Most of the documents on low-carbon farming I have seen recently had a picture of a conventional tractor on the front! Ideas, anyone?
Oldham, Lancashire, UK
Profit and laws
It’s a good question. Under existing trade agreements, arbitration procedures are enforced by the treaty itself and cases are heard and enforced by arbitration panels such as the World Bank’s International Centre for Settlement of Investment Disputes. But nobody knows in the specific case of TTIP because negotiations are ongoing and conducted in private.
Profit and laws
John Middleton cites examples of private companies that sued national governments for loss of profits under agreements similar to the Transatlantic Trade and Investment Partnership (TTIP) (1 November, p 34).
The question that occurred to me as I read about the various instances was of enforceability. If a legal complaint should prove to be well founded and the case awarded to the company, exactly how would the court’s judgment be enforced if the national government simply chose to ignore it?
Harrogate, North Yorkshire, UK
No benefit added
I thoroughly enjoyed reading Tracey Brown’s thoughts on TTIP and regulatory cooperation. However, Brown says chemical regulators look at benefits and risks when making assessments.
The European Chemicals Agency is bound to similar requirement as the European Food Safety Authority and can only consider risk.
Brussels, Belgium
No benefit added
In support of harmonising regulations between the US and Europe through the Transatlantic Trade and Investment Partnership (TTIP), designed to break down barriers to trade, Tracey Brown asks who would defend a return to the wasteful delays of countries running separate clinical drug trials to meet local regulations. (1 November, p 33)
I for one would certainly defend separate clinical trials for statutory approval as well as for better understanding of new pharmaceutical products, given the bias which inevitably enters into these trials.
This wariness of bias is echoed by Iain Chalmers, one of the founders of the Cochrane Foundation, who in 2013 cautioned in the BMJ: “There is clear and consistent evidence of under-reporting and manipulation of the scientific literature by the drug and devices industries, and industry sponsors most of the world’s clinical trials” (). The goal is of course unbiased clinical trials.
Bearsden, Glasgow, UK