I am sure that pretty much everyone has been amazed at stories like the following, of identical twins who had been separated at birth and then reunited as adults.

Thirteen days before the start of the Second World War, a 35-year-old unmarried immigrant woman gave birth slightly prematurely to identical twins at the Memorial Hospital in Piqua, Ohio and immediately put them up for adoption. The boys spent their first month together in a children’s home before Ernest and Sarah Springer adopted one – and would have adopted both had they not been told, incorrectly, that the other twin had died. Two weeks later, Jess and Lucille Lewis adopted the other baby and, when they signed the papers at the local courthouse, calling their boy James, the clerk remarked: ‘That’s what [the Springers] named their son.’ Until then they hadn’t known he was a twin.

The boys grew up 40 miles apart in middle-class Ohioan families. Although James Lewis was six when he learnt he’d been adopted, it was only in his late 30s that he began searching for his birth family at the Ohio courthouse. In 1979, the adoption agency wrote to James Springer, who was astonished by the news, because as a teenager he’d been told his twin had died at birth. He phoned Lewis and four days later they met – a nervous handshake and then beaming smiles.
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Both Jims, it transpired, had worked as deputy sheriffs, and had done stints at McDonald’s and at petrol stations; they’d both taken holidays at Pass-a-Grille beach in Florida, driving there in their light-blue Chevrolets. Each had dogs called Toy and brothers called Larry, and they’d married and divorced women called Linda, then married Bettys. They’d called their first sons James Alan/Allan. Both were good at maths and bad at spelling, loved carpentry, chewed their nails, chain-smoked Salem and drank Miller Lite beer. Both had haemorrhoids, started experiencing migraines at 18, gained 10 lb in their early 30s, and had similar heart problems and sleep patterns.

Incredible, no?
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The Pacific Ocean covers almost half the surface of the Earth and despite its name can be the scene of massive storms. The entire region can be split into three regions, Micronesia and Melanesia that are on the western end of the ocean, close to Australasia, and Polynesia that occupies the central region. Polynesia is vast as can be seen by the size of the so-called Polynesian triangle consisting of Hawaii as the northern vertex, Rapa Nui (formerly called Easter Island) as the southeast vertex, and New Zealand as the southwest vertex. Each side of this triangle is about 9,000 miles. The people of Polynesia, despite being so widely dispersed, form a single, identifiable cultural group.

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Gravity is weird. It is the oldest of the four fundamental forces that we have been able to describe and yet what it is remains mysterious. When Isaac Newton first introduced his theory of gravity and the idea that objects with mass attract each other, he was accused by some critics of introducing a form of mysticism into science by postulating non-contact forces that could act instantaneously over empty space.

Einstein’s theory of general relativity brought in more sophisticated ideas by replacing instantaneous action-at-a-distance between two masses by saying that one mass distorts that space around it and that the distortion spreads through space at the speed of light and that the second mass responds accordingly when that distortion reaches it, thus removing the instantaneous action-at-a-distance problem. His Principle of Equivalence also showed that we cannot distinguish between being in a uniform gravitational field and being subjected to a constant acceleration. When we are in free fall, we are effectively weightless. The catch is that at some point, very quickly, we hit the ground.

Gravity is a ubiquitous force. We cannot shield ourselves from it. All this makes it hard for Earthbound people like us to imagine what life might be like in the absence of gravity. Now with space travel, we see astronauts in space stations in gravity-free situations. It should be noted that that he Earth’s gravitational field at the orbital height of the space station is about 90% of what we feel on Earth. But because they are in free-fall as the station orbits the Earth, they are effectively in zero-gravity (or more accurately microgravity) fields for a long time as long as they are in orbit. This has given us some idea of what life might be like in such an environment but there are still surprises. Part of the surprise is due to the fact that many forces that on Earth are small compared to the Earth’s gravitational field and are swamped by it, become significant when in zero gravity but many people do not realize this.

Take for example, a recent story about a video of Chinese astronauts (they refer to them as taikonauts) that had a glass of water. Since many people expect that in zero gravity water must float in the air in the shape of a sphere, this raised suspicions that the video had not been shot in space. But they are wrong because they ignored how important adhesive forces become in the absence of gravity.
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Dark matter and dark energy have proven to be remarkably elusive, resisting all efforts so far to be directly detected. The best evidence we have for their existence is indirect, through gravitational effects that we have ascribed to their presence. The problem is that the gravitational force is both very weak (the weakest of the four fundamental forces) while at the same time, in the presence of huge masses like the Earth, stars, or galaxies, its effects are also large, dwarfing the effects of other forces. But such indirect evidence for the existence of fundamental particles is never satisfying because scientific history has examples where that has led us astray. So the search goes on, with the construction of evermore sensitive detectors that we hope will finally provide convincing direct evidence.

One of the latest efforts is to send detectors into space.
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Rowan Atkinson is well known as an actor and comedian. But his undergraduate education was in electrical and electronic engineering, with a subsequent master’s degree in control systems. He has written a thoughtful opinion piece on how his early infatuation with electric vehicles as a way to combat climate change has cooled as he learned more about the hidden environmental costs of this technology.

I bought my first electric hybrid 18 years ago and my first pure electric car nine years ago and (notwithstanding our poor electric charging infrastructure) have enjoyed my time with both very much. Electric vehicles may be a bit soulless, but they’re wonderful mechanisms: fast, quiet and, until recently, very cheap to run. But increasingly, I feel a little duped. When you start to drill into the facts, electric motoring doesn’t seem to be quite the environmental panacea it is claimed to be.

As you may know, the government has proposed a ban on the sale of new petrol and diesel cars from 2030. The problem with the initiative is that it seems to be based on conclusions drawn from only one part of a car’s operating life: what comes out of the exhaust pipe. Electric cars, of course, have zero exhaust emissions, which is a welcome development, particularly in respect of the air quality in city centres. But if you zoom out a bit and look at a bigger picture that includes the car’s manufacture, the situation is very different. In advance of the Cop26 climate conference in Glasgow in 2021, Volvo released figures claiming that greenhouse gas emissions during production of an electric car are 70% higher than when manufacturing a petrol one. How so? The problem lies with the lithium-ion batteries fitted currently to nearly all electric vehicles: they’re absurdly heavy, many rare earth metals and huge amounts of energy are required to make them, and they only last about 10 years. It seems a perverse choice of hardware with which to lead the automobile’s fight against the climate crisis.

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