May the force not be with you: Sandra Bullock goes for a spacewalk in Gravity. Photo: Warner Bros
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In search of the notorious Big G: why we still know so little about gravity

Gravity is pathetic and so is our understanding of it.

Gravity is pathetic. The Oscar statuette, for instance, has a mass of 3.85 kilograms but it is pulled down to earth by a force so weak that you can buy a £2.99 fridge magnet that can beat it. It’s shameful that the gravitational pull of the entire earth can be overcome by a cheap piece of magnetised steel.

Gravity is by far the weakest of the fundamental forces of nature (the fridge magnet puts the far stronger electromagnetic force to work). It is so weak that its strength is proving difficult to measure accurately. In late February, while Alfonso Cuarón, the director of the sci-fi film Gravity, was on tenterhooks waiting for the Oscars result, the world’s experts on gravity assembled just outside Milton Keynes in an attempt to sort out this most embarrassing problem.

Numbers such as the strength of gravity, the speed of light and the charge on an electron are known to physicists as the “fundamental constants”. They are in some ways the sticking plaster of physics. We can explain the origin of most things but we know the values of the fundamental constants only by measuring them – there is no way to work them out from a theory.

These days, most are very well defined – but not gravity. It is the only fundamental constant for which our uncertainty over its value has got worse over the years.

The gravitational constant is sometimes known as “Big G”. This differentiates it from “little g”, which describes how fast things accelerate towards Planet Earth when free to fall. The first accurate measurement of Big G was made in 1798. Henry Cavendish used a torsion balance, a device in which two lead weights are attached to the ends of a metal bar. The bar hangs horizontally by a metal wire attached to its midpoint. Cavendish then brought other weights close to one of the lead weights and measured how much the gravitational attraction between the weights twisted the wire. From that measurement, he calculated the strength of gravity.

Cavendish’s accuracy was five parts in 1,000. Over 200 years later, our accuracy stands at roughly one part in 10,000. Given that modern measurements use lasers and electronic devices and Cavendish used a mirror and a candle, it hardly counts as a great improvement.

What’s worse is that our measurements of Big G are getting less accurate. The latest measurement, reported at the end of last year, reduced the overall value by 66 parts per million but the uncertainty
of the value increased from 100 parts per million to 120 parts per million.

The measurement was taken by Terry Quinn, emeritus director of the International Bureau of Weights and Measures in Paris. At its meeting in February, he argued that it was time researchers admitted that everyone must be making some basic errors in their method and that they should give up on making any more unilateral measurements.

The experts now agree that future experiments seeking the value of Big G will be done in big collaborations, with the proposals for equipment and methodology being scrutinised by everyone in advance to minimise the chance of further embarrassment.

It will, they say, mimic the way that researchers worked together to find the Higgs boson. That gave us the secret of mass: the hope is that if the physicists all pull together, they can finally work out exactly what size of force brings that mass down to earth.

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 05 March 2014 issue of the New Statesman, Putin's power game

Flickr: woodleywonderworks
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Lol enforcement: meet the man policing online joke theft

A story of revenge, retweets, and Kale Salad. 

A man walks into a bar and he tells a joke. The man next to him laughs – and then he tells the same joke. The man next to him, in turn, repeats the joke. That bar’s name is Twitter.

If you’ve been on the social network for more than five minutes, you’ll notice that joke theft is rampant on the site. Search, for example, for a popular tweet this week (“did everyone just forget about the part of 2016 when literal clowns would chase people with knives in public and nobody really did anything” – 153,000 retweets) and you’ll see it has been copied 53 times in the last three days.

One instance of plagiarism, however, is unlike the others. Its perpetrator is the meme account @dory and its quick Ctrl+C, Ctrl+V has over 3,500 retweets. This account frequently copies the viral posts of Twitter users and passes them off – word for word – as its own. Many similar accounts do the same, including @CWGirl and @FatJew, and many make money by promoting advertising messages to their large number of followers. Twitter joke theft, then, is profitable.

In 2015, Twitter promised to clamp down on the unchecked plagiarism on its site. “This Tweet from [user] has been withheld in response to a report from the copyright holder,” read a message meant to replace stolen jokes on the site. It’s likely a message you’ve never seen.

Dissatisfied with this solution, one man took it upon himself to fight the thieves. 

“I'm a like happy internet kind of guy,” says Samir Mezrahi, a 34-year-old from New York who runs the Twitter account @KaleSalad. For the last six months, Mezrahi has used the account to source and retweet the original writers of Twitter jokes. Starting with a few hundred followers at the end of December 2016, Mezrahi had jumped to 50,000 followers by January 2017. Over 82,000 people now follow his account.  

“I've always been a big fan of like viral tweets and great tweets,” explains Mezrahi, over the sound of his children watching cartoons in the background. “A lot of people were fed up with the meme accounts so it’s just like a good opportunity to reward creators and people.”

Samir Mezrahi, owner of @KaleSalad

I had expected Mezrahi to be a teen. In actual fact he is a father of three and an ex-Buzzfeed employee, who speaks in a calm monotone, yet is enthusiastic about sharing the best content on Twitter. Though at first sourcing original tweets for Kale Salad was hard work, people now approach Mezrahi for help.

“People still reach out to me looking for vindication and just that kind of, I don’t know, that kind of acknowledgement that they were the originals. Because all so often the meme accounts are much larger and their tweets do better than the stolen tweet.”

But just why does having a tweet stolen suck so much? In the grand scheme of things, does it matter? Did everyone just forget about the part of 2016 when literal clowns would chase people with knives in public and nobody really did anything?

Meryl O’Rourke is a comedian and writer who tweets at @MerylORourke, and now has a copyright symbol (©) after her Twitter name. In the past she has had her jokes stolen and reposted, unattributed, on Facebook and Twitter and hopes this symbol will go some way to protecting her work.

“It’s hard to explain how it felt... as a struggling writer you’re always waiting for anything that looks like recognition as it could lead to your break,” she explains. “When your work gains momentum you feel like your opportunity ran off without you.

“Twitter is a test of a writer’s skill. To spend time choosing exactly the right words to convey your meaning with no nuance or explanation, and ensure popularity and a chuckle, in the space of only 140 characters – that’s hard work.”

However, Mezrahi has found not everyone is bothered by their tweets being stolen. I found the same man I reached out to with a stolen tweet who said he didn’t want to speak to me because it felt too “first world problems” to complain. Writers like O’Rourke are naturally more annoyed than random teenagers, who Mezrahi says are normally actually pleased about the theft.

“If you go to [a teenager’s] timeline it’s always the same thing. They’re replying to all their friends saying like ‘I’m famous’, they’re retweeting the meme accounts saying like ‘I did it’… they don’t mind as much it seems. It’s kind of like a badge of honour to them.”

Sometimes, people even ask Kale Salad to unretweet their posts. College students with scholarships, in particular, might not actually want to go viral – or some viral tweets may accidentally include personal information. On the whole, however, people are grateful for his work.

Yet the Kale Salad account does have unintended consequences. Mezrahi has now been blocked by the major meme accounts that frequently steal jokes, meaning he had to create alternate accounts to view their content. But just because he can’t see them doesn’t mean they don’t see him – and he has noticed that these accounts now actually come to his profile to steal jokes he has retweeted, in a strange role-reversal.

“There are definitely times when they're picking up things that I just retweeted, like I know they're like looking at me too,” he says. “It feels like vindicated or validated that they come to me.”

Mezrahi now works in social media on a freelance basis, but would be open to making Kale Salad profitable. Earlier this year he set up an account on Patreon – a site that allows fans to pay their favourite creators. Some people didn’t approve of this, tweeting to say he is “just retweeting tweets”. So far, Mezrahi has three patrons who pay him $50 (£39) a month.

“I mean I spend a certain amount of time on this and I think it’s a pretty good service, so I've been thinking about monetisation and thought that might be a route,” he explains. He believes he is providing an important service by “amplifying” creators, and he didn’t want to make money in less transparent ways, such as by posting sponsored advertisements on his account. Yet although many online love Kale Salad, they don’t, as of yet, want to pay him.

“Twitter should buy my account because I’m doing a good thing that people like every day,” he muses.

Many might still be sceptical of the value of a joke vigilante. For those whose jokes aren’t their bread or butter, tweet theft may seem like a very minimal problem. And although it arguably is, it’s still incredibly annoying. Writing in Playboy, Rob Fee explains it best:

“How upsetting is it when you tell a joke quietly in a group of friends, then someone else says it louder and gets a huge laugh? Now imagine your friend following you every day listening for more jokes because people started throwing money at him every time he repeated what you said. Also, that friend quit his job because he made enough to live comfortably by telling your jokes louder than you can. Odds are, you’d quickly decide to find new friends.”

For now, then, Kale Salad will continue his work as the unpaid internet police. “As long as people like the service, I don’t mind doing it. If that's a year or two years or what we'll see how the account goes,” he says.

“Twitter is fun and I like the fun days on the internet and I like to help contribute to that.

“The internet is for fun and not all the sadness that’s often there.”

Amelia Tait is a technology and digital culture writer at the New Statesman.

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