High voltage: Hinkley power stations near Bristol. Photo: Getty
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Path of least resistance: the quest for room-temperature superconductors

Michael Brooks’s Science Column. 

We don’t talk enough about superconductors. These materials carry electricity without losing energy and could change the world – if only we could rediscover the kind of progress we used to make in this field.

We have known about superconductors since 1911, when the first one was discovered. In normal conductors – an aluminium wire at room temperature, for instance – electrons move through the material, jostled by all the other particles. Cool that aluminium down to -272° Celsius, though, and it becomes a superconductor. The electrons encounter no resistance, zipping along the wire as if they were the only particles in town.

That is significant: the copper cables used to transmit electricity from power stations to your home lose 10 per cent of energy through electrical resistance. If those cables were made of a superconductor, no energy would be lost. We would not need to generate so much power, reducing our dependence on fossil fuels.

Even better would be the ability to store energy. Renewable sources such as wind, wave and solar power generate energy at times and rates beyond our control. That power could be stored indefinitely in superconducting circuits. Because these don’t dissipate any of the energy, a superconducting power store is a battery whose charge lasts as long as you need it to.

There are also transport applications. Superconductors repel magnets and engineers have exploited this by putting superconductors on trains and electromagnets on the track. The repulsion levitates the train above the track, hugely reducing friction and clearing the way for ultra-fast transport.

So far, though, magnetic levitation trains have taken off in only a couple of places around the world. That is because superconductors are still not super enough. The main problem is that more energy is spent to cool materials until they become superconducting than is saved through reduced transmission loss, better energy storage capacity or greater transport efficiency.

This is a tale of dashed hopes. From 1911 to the 1980s, superconductors were available at temperatures below -240° Celsius only. We thought we had beaten this barrier in 1986 when we discovered a copper compound that was superconducting at -183° Celsius. Suddenly, things were looking up: we could turn materials superconducting by cooling them with liquid nitrogen, a relatively cheap and easy means of refrigeration.

However, it still wasn’t cheap and easy enough to make superconducting technology mainstream. So we cooked up more of these “high-temperature superconductors”. By 1993, we had got to about -140° Celsius. Things were looking very good indeed. And then, almost nothing. We are still less than halfway to room-temperature superconductors.

That’s because, despite decades of research, we’re still trying to figure out how they work. Progress is painfully slow. In October, French and US researchers finally confirmed a prediction, made in 1964, about one microscopic characteristic of what is going on inside superconductors.

This latest breakthrough might lead to superconductors that can withstand higher magnetic fields and thus give hospitals better MRI scanners – but it won’t push that critical transition point up towards room temperature. We can only hope that will be achieved by the researchers investigating other features of superconduction. No one thinks such a breakthrough is imminent. In an age when we have come to understand some of the deepest secrets of the universe, the secrets of the superconductor are keeping our feet firmly on the ground. 

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 13 November 2014 issue of the New Statesman, Nigel Farage: The Arsonist

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Why have men become so lonely – and how does it affect their health?

New findings show the consequences of having a lonely heart.

Go out and get some friends. No, seriously. Hop on the Tube and act faux-interested in the crap-looking book your fellow commuter is reading, even if it's on their Kindle. Chances are it's better than the one in your bag, and they're probably a decent human being and just as lonely, like you and me.

A new slate of facts and figures are showing just how widespread loneliness, is while simultaneously being amazingly terrible for your health.

Research led by Steven Cole from the medicine department at University of California, Los Angeles is showing the cellular mechanisms behind the long known pitfalls of loneliness. Perceived social isolation (PSI) – the scientific term for loneliness –increases the exposure to chronic diseases and even mortality for individuals across the world.

The authors examined the effects of loneliness on leukocytes, also known as white blood cells, which are produced from stem cells in the bone marrow and are critical to the immune system and defending the body against bacteria and viruses. The results showed loneliness increases signalling in the sympathetic nervous system, which is responsible for controlling our fight-or-flight responses, and also affects the production of white blood cells.

Recently, the Movember Foundation, which focuses on men's health and wellbeing, carried out a survey with the help of YouGov investigating friendship and loneliness amongst men. The results are alarming, with only 11 per cent of single men across the spectrum in their early 20s to late-middle age saying they had a friend to turn to in a time of crisis, the number rising to 15 per cent for married men.

Friendship has shown not only to be important to a person's overall wellbeing, but can even add to a person's earnings. A previous study involving 10,000 US citizens over 35 years showed people earned 2 per cent more for each friend they had.

The Movember Foundation survey comes soon after the Office for National Statistics (ONS) showed that men in Britain make up 58 per cent of the 2.47m people living alone between the ages of 45 and 64. The reasons behind this figure include marrying later in life and failed marriages, which usually result in children living with the mother. Women still make up the majority of the 7.7m single-occupant households across all ages in the country, at approximately 54 per cent.

Chronic loneliness seems to have slowly become a persistent problem for the country despite our hyper-connected world. It's an issue that has made even Jeremy Hunt say sensible things, such as "the busy, atomised lives we increasingly lead mean that too often we have become so distant from blood relatives" about this hidden crisis. He's previously called for British families to adopt the approach of many Asian families of having grandparents live under the same roof as children and grandchildren, and view care homes as a last, not first, option.

The number of single-person households has continued to increase over the years. While studies such as this add to the list of reasons why being alone is terrible for you, researchers are stumped as to how we can tackle this major social issue. Here's my suggestion: turn off whatever screen you're reading this from and strike up a conversation with someone who looks approachable. They could end up becoming your new best friend.