With all things wizardly being topical, what better time to examine one of the practical skills that every self-respecting wizard should master: alchemy? But this near-magical ability to turn base metals into gold is not confined to fiction.
The quest for the philosopher's stone that has the power to transmute one substance into another has been the obsession of many great thinkers throughout history. The wealth and power that would come to anyone who mastered alchemy seduced many great scientists and philosophers, including Isaac Newton, Robert Boyle and John Locke. All tried to change one element into another, and all failed.
Then in 1919, the secret of alchemy was finally revealed in the physics department at Manchester University. The world's first successful alchemist was the New Zealand scientist and Nobel prize winner Ernest Rutherford, and his discovery was almost accidental. It began when one of his students noticed that when radioactive materials such as radium were placed in a sealed box of air, small amounts of hydrogen, which doesn't exist in ordinary air, began to mysteriously appear. Rutherford realised that in the presence of the powerful radioactive rays, nitrogen, which makes up more than three-quarters of the air we breathe, turns into two other gases -- hydrogen and oxygen.
The alpha particles being produced by the radium were embedding themselves within the nuclei of nitrogen atoms while knocking out single protons. What remained was an oxygen nucleus, while the protons themselves were actually nuclei of hydrogen. All that is needed then is for these nuclei to accumulate the requisite number of electrons and they become atoms of the respective gases.
Today, changing one element into another through such nuclear reactions is routine. What is exciting, and yet not widely known, is that such subatomic alchemy might end up playing a vital part in the way we produce clean energy in the future.
A loose interpretation of the second law of thermodynamics is that "there is no such thing as a free lunch."
And so it is with electrical energy production. If you burn fossil fuels, you generate carbon dioxide; if you build dams, you destroy the ecology of entire valleys.
Nuclear power is no exception. If you carry out controlled fission in a nuclear power station, you get long-lived radioactive waste, and that poses a long-term hazard to the environment unless it is dealt with properly. This has justifiably caused concern among many who would otherwise welcome nuclear power as a source of clean, carbon-free energy.
The favored option is to store the treated and vitrified waste in deep geological repositories. Understandably, people don't want this in their backyard, because material such as plutonium remains radioactive for tens of thousands of years. In the throes of deciding future energy policy, such concerns are a serious issue.
I find this a very strange concern; here we are trying to figure out how to avert the disaster of climate change, and yet the long-term problem of nuclear waste still worries us. Human civilization started less than 10,000 years ago, so to worry whether we'll be technologically advanced enough to deal with this buried waste thousands of years in the future, assuming we survive climate change, is utterly irrational. And, what if there was a way to incinerate the nuclear waste, destroying nearly all that plutonium and dramatically reducing the need for long-term storage?
One such strategy is known as accelerator-driven transmutation. The basic idea is to place the radioactive material in a machine and smash it up into much more stable products, with shorter half-lives using a beam of high-energy subatomic particles. The waste would still need to be stored, but would be much less hazardous. At the same time, the process of transmutation would eliminate other biologically toxic products that exist in "normal" nuclear waste.
The real beauty of the process is that it could generate more energy than is pumped in. The heat generated by splitting the waste nuclei can be used to generate electricity, part of which is used to run the accelerator and the rest fed into the national grid. The failsafe mechanism is that when the beam is turned off, the reaction stops. This type of plant is known as an "energy amplifier" and the idea has been around since the 1990s.
So how feasible is this ability to transmute our nuclear waste? More importantly, why is no one talking about it? After all, the nuclear waste problem is seen as one major obstacle stopping many people from embracing nuclear power as one of the key ingredients in carbon-free energy generation.
It is a source of deep concern that so many people still believe we can slash our reliance on coal and gas solely through renewable sources, such as wind and solar, along with energy conservation in buildings. These are vital, but if we are going to avert the disasters of climate change while enjoying the standard of living that most in the west would be unwilling to give up, we are going to have to continue our reliance on nuclear energy. If transmutation could be made to work, it would go a long way towards helping the world come to terms with it. Beyond this timescale, we are now finally and genuinely optimistic that the ultimate energy source will come online: nuclear fusion. But that's another story.
France has a well-funded program of research looking into transmutation. There are also initiatives in the US, Russia, Switzerland, Italy and Japan, which the UK government continues to "monitor." The reason no one has perfected the technology yet is that while in theory it should work, we still do not know exactly what the final transmutation products will be, and in what proportions.
The scientific community has to understand the science involved and the technology needed, its practicalities and potential impacts.
This takes years. The US and Europe have produced roadmaps of timescales of 20 to 35 years. Unfortunately, the nuclear industry does not see transmutation as viable and the onus is therefore on us to urge governments to act.
Many experts argue that while transmutation is a feasible future technology, there are several other options available too. The most widely touted is to use what is a called a fast-breeder reactor that would re-use the nuclear fuel over and over again until all the plutonium is burned up. Another option many nations are looking into is to use thorium as the basic nuclear fuel. It is more abundant in nature than uranium, and much less radioactive material is produced compared with uranium fuel cycles.
With all these options for coping with nuclear waste it is disappointing that what little public debate there has been in the UK seems to have been aimed at answering the question of "should we" rather than the question of "could we." The answer to the latter is only likely to be found in an effort involving scientists from a wide range of fields. Then the philosopher's stone will be within our grasp once more.
Jim Al-Khalili is professor of physics and professor of public engagement in science at the University of Surrey, as well as this year's recipient of the Royal Society Michael Faraday prize for science communication.
Since COVID-19 broke out in Taiwan, there has been a fair amount of news regarding discrimination and “witch hunts” against medical personnel, people under self-quarantine and other targets, such as the students of a school where an infection was discovered. Quarantine breakers are almost certainly on the loose and it is only natural for people to be vigilant. One in Chiayi was found by accident at a traffic stop because his helmet was not fastened. However, those who follow the rules by quarantining themselves should be encouraged to keep up the good work in a difficult situation, instead of being
Chinese Nationalist Party (KMT) Legislator-at-large Wu Sz-huai (吳斯懷) has said that there is a huge difference between Chinese military aircraft circling Taiwan along the edges of its airspace and invading Taiwan’s airspace. He also said that whether it is US or Chinese aircraft flying along or encircling Taiwan’s airspace, there is no legal basis to say that such actions imply a clear provocation of Taiwan, and asked the Ministry of National Defense not to mislead the public. People who hear this might think that it is not a very Taiwanese thing to say. US military activity in the vicinity of Taiwan
As the nation welcomes home Taiwanese who had been stranded in China’s Hubei Province — arguably one of the most dangerous places on Earth since the novel coronavirus outbreak began in its capital, Wuhan, late last year — problems surrounding the “quasi-charter flights” that brought them back have been largely overlooked. The media used the term to describe the two flights dispatched by Taiwan’s state-run China Airlines because they do not count as charter flights. Taiwanese wanting to board those flights had to travel — most likely by train — more than 1,000km from Hubei to Shanghai Pudong International Airport
As the COVID-19 pandemic spins out of control, many parts of the world are experiencing shortages of medical masks and other protective equipment. I am studying in Washington state, which at the time of writing is the US state that has suffered the largest number of deaths from the novel coronavirus. The week before last, UW Medicine — an organization that includes the University of Washington School of Medicine and associated medical centers and clinics — sent its volunteers an e-mail asking the public to make masks and donate them to hospitals. Attached to the message was a mask donation