Good chemistry: a display of cupcakes iced with chemical element symbols. Photo: Flickr
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The Periodic table versus the Apocalypse

Not just a faded poster on a lab wall, but “as impressive as the Pyramids or any of the other wonders of the world”. The table also holds the key to finding replacements for antibiotics. 

This month, researchers will gather at the Royal Society for two days of meetings about the periodic table of the elements. To most people, the phrase conjures up images of a fading poster on a chemistry lab wall – but to scientists, it is “the most fundamental natural system of classification ever devised” (in the words of the organisers).

And it’s not a thing of the past – the periodic table is still inspiring new angles of research. Because it suggests connections and similarities between elements, it is a source of ideas for extending our range of tools for manipulating nature and finding medical solutions. That third row of transition metals, for instance, might look boring but it isn’t if you have cancer. More than half of chemotherapy patients receive platinum in their treatment but it may not be as effective as some of the other metals in the third row, such as osmium and rhenium, research is discovering.

The periodic table has come a long way since its creation. We have added dozens of elements and have even learned to make 26 elements that nature didn’t get round to creating. By examining the building blocks of the natural world, we have designed some blocks of our own and extended the natural atomic scope by almost a third. According to the astrobiologist Lewis Dartnell, the periodic table is “a colossal monument to achievement, as impressive as the Pyramids or any of the other wonders of the world”. He makes this claim in his book The Knowledge, which was published last month.

In some ways, the book is a hymn to human ingenuity, charting how we have taken control of the planet, engineered solutions to the many problems that plagued us as we developed modern societies and learned to beat our microbial assailants to live ever longer lives. Yet it is more than that. It is a manual for rebuilding society in the face of catastrophe.

The periodic table makes an appearance because reading its patterns after the Apocalypse will help us find ways to exploit the properties offered by natural substances. It may be worth starting now, however.

At the end of April, the World Health Organisation warned that antibiotic resistance is reaching epidemic proportions. “The world needs to respond as it did to the Aids crisis of the 1980s,” the microbiologist Laura Piddock told the Telegraph. We need to do far better than that. Our initial response to the Aids crisis was inadequate at best.

We are doing so well in the fight against Aids (in the global north, at least) because of Aids activists, not scientists. Scientific research into HIV and Aids was ready to sacrifice an entire generation of patients in the pursuit of carefully managed experimental data. This wasn’t because scientists were indifferent to the problem. They cared, but science, left to its own devices, is not a fast worker. That was why the patients rebelled and forced governments to adopt a crisis approach.

The intervention worked and there is every reason to think this could happen again with antibiotics. Researchers have been warning of the growing threat from antibiotic resistance since the 1980s. We are trawling for new ready-made alternatives but there are other avenues to explore, too. We know, for instance, that the answer to antibiotic resistance, if there is one, must lie within the elements of the periodic table, or the combinations they offer. The periodic table in hand, we need to implement an emergency procedure – before Dartnell’s book becomes essential reading.

Michael Brooks holds a PhD in quantum physics. He writes a weekly science column for the New Statesman, and his most recent book is At the Edge of Uncertainty: 11 Discoveries Taking Science by Surprise.

This article first appeared in the 08 May 2014 issue of the New Statesman, India's worst nightmare?
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The Earth moved: how we discovered ripples in space time

A new book charts the decades-long search to measure gravitational waves.

Monday 14 September 2015 was no ordinary day. At exactly 09:50:45 Universal Time, for one-fifth of a second, the Earth was stretched and squeezed by a tenth of a quintillionth of one per cent. Everything on the planet expanded and contracted as it did by one part in 1021 (1 followed by 21 noughts). It was proof that after a decades-long search, scientists had finally developed instruments sensitive enough to detect gravitational waves – ripples in space-time that were 10,000 times smaller than the nucleus of a hydrogen atom.

That at least begins to take care of when, where and what happened that Monday morning. In this engaging book the Dutch science writer Govert Schilling goes on to deal with the who and why by telling the tale of those involved in making what has been dubbed by some as “the discovery of the century” and the reason those unimaginably tiny ripples in space-time originated in a catastrophic event 1.3 billion years ago in a galaxy far, far away.

The “who” starts with a 36-year-old German physicist who in 1915 had just completed his masterwork, general relativity. In Albert Einstein’s new theory, gravity was due to the warping of space by the presence of mass. The Earth moves around the sun not because some mysterious invisible force pulls it, but because the warping of space tells matter how to move, while matter tells space how to curve. General relativity revealed that the familiar three-dimensions of space and the passage of time are not independent and absolute but are woven together into a four-dimensional fabric called space-time.

Einstein was fallible. Although vibrations in the fabric of space-time are a distinctive consequence of general relativity, Einstein wrote that “there are no gravitational waves”. He soon changed his mind; but the hunt for gravity waves using detectors in the lab would not begin until the late 1950s.

The Laser Interferometer Gravitational-wave Observatory, LIGO, was given the green light in 1990 by the US National Science Foundation, despite a $300 million price tag. By 2015 the project involved two similar detectors housed in facilities some 3,000 kilometres apart – one in Hanford, Washington State, the other in Livingston, Louisiana. A single detector would register microseismic events, such as passing cars; to exclude these false alarms, experimenters would take note only of events that showed up in both detectors within a few milliseconds of each other.

In the LIGO detectors, laser beams are fired along 4km-long L-shaped vacuum pipes and reflected from mirrors at each end. By analysing the light beams, it is possible to detect changes in the distance between the mirrors, which increases and decreases as space expands and contracts due to a passing gravitational wave. But the effect is tiny because gravity is a weak force and space-time is not easy to flex, bend, stretch or compress. A lot of energy is required for the tiniest ripples. Even pairs of stars orbiting each other don’t generate gravitational waves that LIGO can detect; but events involving black holes would.

Black holes, another prediction of general relativity, are the remnants of stars many times more massive than the sun. These stars burn brightly, and in their death throes, signalled by going supernova, their inner part collapses to form a black hole.

GW150914, the first gravitational wave detected by LIGO on 14 September 2015, was produced by the merger of two black holes that were 36 and 29 times as massive as the sun. As those two black holes orbited each other 1.3 billion years ago, they generated minute ripples in space-time that propagated with the speed of light. The waves carried away energy, causing the two holes to spiral ever closer, orbiting each other hundreds of times a second. As space-time was stretched and squeezed, the tiny perturbations grew into massive waves. When the two black holes collided and merged into one, a tsunami of gravitational waves was generated. These cataclysmic collisions happen less than once in a million years in our galaxy, but there are at least 100 billion galaxies in the observable universe.

“When I am judging a theory, I ask myself whether, if I were God, I would have arranged the world in such a way,” Einstein once confessed. Perhaps only he or Newton could get away with such a statement; the rest have to rely on the close relationship between theoretical insight and experimental scrutiny that lies at the heart of the scientific method. Wherever evidence can be coaxed out of nature, it corroborates or refutes a theory and serves as the sole arbiter of validity. Gravity waves are another tick for general relativity and the first direct proof of the existence of black holes; all other evidence has been circumstantial.

The hunt for gravity waves is over, but gravitational wave astronomy may help solve some mysteries that continue to baffle physicists: such as the nature of dark matter and dark energy, which together make up 96 per cent of the universe.

Ripples in Spacetime: Einstein, Gravitational Waves, and the Future of Astronomy
Govert Schilling
Harvard-Belknap, 340pp, £23.95

Manjit Kumar is the author of “Quantum: Einstein, Bohr and the Great Debate About the Nature of Reality” (Icon)

This article first appeared in the 17 August 2017 issue of the New Statesman, Trump goes nuclear