Albert Einstein, whose general theory of relativity is still fueling new work. Photo: -/AFP/Getty Images
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What’s up with gravity?

Cheer the discovery of the gravitational wave when it happens. But don’t be fooled: gravity will remain our greatest mystery for a long time yet.

Get ready for a lot of Einstein love. This year marks the centenary of Einstein’s general theory of relativity, which describes how gravity works. Sort of.

It does enough, for instance, to predict the existence of gravitational waves – ripples in space caused by objects moving within it. Not that we have ever seen one. US scientists have just celebrated the completion of their latest gravitational wave detector, which will turn on later this year. They hope to use them to spot the shaking caused by cataclysmic events, such as the collision of two black holes or a supernova explosion.

No one doubts that the waves do exist. Whether our detectors will prove sensitive enough to see them is another matter. Even if they do, it will be a hollow victory. General relativity will have ticked another box but it won’t advance our basic understanding of how gravity works. The truth is that this remains a mystery.

What we do know is that when you throw a ball up in the air, it returns to earth. That’s because the ball and the earth possess a quality called mass: a way of quantifying how difficult it is to accelerate something, to get that ball moving, or to change its path, or stop it. We can describe how something that has mass will move under the influence of something else with mass by calculating the geometry of the object’s gravitational field using Einstein’s mathematics.

Put simply, anything with mass warps the space (and time) around it, and an object travelling through this warped space follows a curved path. In the case of the ball, that means falling back down to earth. In the case of the earth moving past the sun, it means moving in an elliptical orbit rather than a line. After this, we’re hand-waving. Yes, we can do calculations and we can make predictions of phenomena that this warping of space and time will create. But gravity remains our least-understood force – by a very long way.

Take its weakness. The ball falls to earth, but a fridge magnet doesn’t fall off the fridge, even with the mass of the whole planet pulling on it. That’s seven million billion billion kilos losing out to a magnet the size of a coin. If you want to write down how much stronger than gravity the electromagnetic force is, you’ll need a 1 and 40 zeroes.

What’s more, our theory of magnets is much more complete than our theory of gravity. Gravity aside, we can describe all the forces using a mathematical description known as quantum field theory – a framework that lays out how energy, mass, space and time work together to create the forces we see in the universe. According to this theory, particles borrow energy thanks to the “uncertainty principle” of quantum mechanics, using it to create particles that pop in and out of existence. This is no flight of fancy: these “virtual” particles have been found for all the forces. They are the photon, the gluon and the W, Z and Higgs particles.

But we haven’t come close to finding anything that would constitute the “graviton”. Although we can understand the basic electromagnetic and nuclear forces that give us atoms, chemistry and all our electronic gadgets, we don’t have a bottom-up understanding of why a ball falls back to earth.

So cheer the discovery of the gravitational wave when it happens. But don’t be fooled: gravity will remain our greatest mystery for a long time yet.

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 27 May 2015 issue of the New Statesman, Saying the Unsayable

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Did your personality determine whether you voted for Brexit? Research suggests so

The Online Privacy Foundation found Leave voters were significantly more likely to be authoritarian and conscientious. 

"Before referendum day, I said the winners would be those who told the most convincing lies," Paul Flynn, a Labour MP, wrote in these pages. "Leave did." The idea that those who voted for Brexit were somehow manipulated is widely accepted by the Remain camp. The Leave campaign, so the argument goes, played on voters' fears and exploited their low numeracy. And new research from the Online Privacy Foundation suggests this argument may, in part at least, be right. 

Over the last 18 months the organisation have researched differences in personality traits, levels of authoritarianism, numeracy, thinking styles and cognitive biases between EU referendum voters. The organisation conducted a series of studies, capturing over 11,000 responses to self-report psychology questionnaires and controlled experiments, with the final results scheduled to be presented at the International Conference on Political Psychology in Copenhagen in October 2017.

The researchers questioned voters using the "Five Factor Model" which consists of five broad personality traits - Openness, Conscientiousness, Extraversion, Agreeableness and Neuroticism. They also considered the disposition of authoritarianism (it is not considered a personality trait). Authoritarians have a more black and white view of the world around them, are more concerned with the upkeep of established societal traditions and have a tendency to be less accepting of outsiders. 

So what did they uncover? Participants expressing an intent to vote to leave the EU reported significantly higher levels of authoritarianism and conscientiousness, and lower levels of openness and neuroticism than voters expressing an intent to vote to remain. (Conscientiousness is associated with dependability, dutifulness, focus and adherence to societal norms in contrast to disorganisation, carelessness and impulsivity.)

Immigration in particular seems to have affected voting. While authoritarians were much more likely to vote Leave to begin with, those who were less authoritarian became increasingly likely to vote Leave if they expressed high levels of concern over immigration. These findings chime with research by the Professors Marc Hetherington and Elizabeth Suhay, which found that Americans became susceptible to "authoritarian thinking" when they perceived a grave threat to their safety. 

Then there's what you might call the £350m question - did Leave voters know what they were voting for? When the Online Privacy Foundation researchers compared Leave voters with Remain voters, they displayed significantly lower levels of numeracy, reasoning and appeared more impulsive. In all three areas, older voters performed significantly worse than young voters intending to vote the same way.

Even when voters were able to interpret statistics, their ability to do so could be overcome by partisanship. In one striking study, when voters were asked to interpret statistics about whether a skin cream increases or decreases a rash, they were able to interpret them correctly roughly 57 per cent of the time. But when voters were asked to interpret the same set of statistics, but told they were about whether immigration increases or decreases crime, something disturbing happened. 

If the statistics didn't support a voter's view, their ability to correctly interpret the numbers dropped, in some cases, by almost a half. 

Before Remoaners start to crow, this study is not an affirmation that "I'm smart, you're dumb". Further research could be done, for example, on the role of age and education (young graduates were far more likely to vote Remain). But in the meantime, there is a question that needs to be answered - are political campaigners deliberately exploiting these personality traits? 

Chris Sumner, from the Online Privacy Foundation, warns that in the era of Big Data, clues about our personalities are collected online: "In the era of Big Data, these clues are aggregated, transformed and sold by a burgeoning industry."

Indeed, Cambridge Analytica, a data company associated with the political right in the UK and US, states on its website that it can "more effectively engage and persuade voters using specially tailored language and visual ad combinations crafted with insights gleaned from behavioral understandings of your electorate". It will do so through a "blend of big data analytics and behavioural psychology". 

"Given the differences observed between Leave and Remain voters, and irrespective of which campaign, it is reasonable to hypothesize that industrial-scale psychographic profiling would have been a highly effective strategy," Sumner says. By identifying voters with different personalities and attitudes, such campaigns could target "the most persuadable voters with messages most likely to influence their vote". Indeed, in research yet to be published, the Online Privacy Foundation targeted groups with differing attitudes to civil liberties based on psychographic indicators associated with authoritarianism. The findings, says Sumner, illustrate "the ease with which individuals' inherent differences could be exploited". 

Julia Rampen is the digital news editor of the New Statesman (previously editor of The Staggers, The New Statesman's online rolling politics blog). She has also been deputy editor at Mirror Money Online and has worked as a financial journalist for several trade magazines. 

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