Dynamite with a laser beam: artist Yvette Mattern's Global Rainbow in Whitley Bay, 2012. Photo: Getty
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Firing lasers into a box made of gold – the race to turn light particles into matter

This could prove a neater way to investigate the fundamental building blocks of nature than examining the debris created by high-energy particle collisions.

By the time you read this, someone might already have done it. The publication of a report in May marked the beginning of the race to turn light into matter. Once the race is won, we could enter a new era in particle physics experiments but the real prize is far more valuable. This is about understanding the roots of our existence.

The idea of creating particles from light was dreamed up in 1934. The basic procedure is to smash together two photons, which are bundles of light energy. Calculations showed that, if done correctly, two particles of matter would magically appear in place of the light. The procedure invokes Albert Einstein’s equation E=mc2. The same equation lies behind the release of energy from nuclear fission. Not only do we now have atomic bombs but, it turns out, we also have the technology to take things in the opposite direction.

A team of physicists from Imperial College London has worked out the details. To collide photons to make matter, first fire a laser into an empty box made of gold. This creates a sea of photons with enormous amounts of energy. At the same time, accelerate a beam of electrons to nearly the speed of light using another high-power laser. Slam those electrons into a slab of gold and they will release a stream of photons to collide with the sea of photons in the gold box. The result will be the creation of electrons – one of the building blocks of matter – and positrons, the electron’s antimatter particle.

Now that it’s clear how to do it, there is little stopping scientists from performing this astonishing trick tomorrow. There are many facilities around the world that could string the various necessary technologies together.

What’s more, ramp up the energies of the lasers and it should eventually be possible to create bigger, heavier particles out of light. This could prove a neater way to investigate the fundamental building blocks of nature than examining the debris created by high-energy particle collisions in machines such as Cern’s Large Hadron Collider. Yet the big spin-off of such feats is in firing the imagination. This is science for the soul.

What this branch of physics teaches us is that our everyday intuition is not to be trusted. That matter and energy are two forms of the same stuff is entirely counter-intuitive. We have long given intellectual assent to the idea but it is so far removed from our day-to-day experience of the world that it may always seem implausible.

This interplay of light and matter is the rock on which the modern world is built. The silicon microchips in your smartphone and your laptop – maybe even your toaster – rely on the fluidity of matter. The microscopic electrical switches they contain work only because electrons are both matter and energy, flowing from one existence to the other as circumstances dictate.

Equally, we are solidly matter in our experience, yet we now know that we are made of stuff that can, in the right circumstances, be transformed into flashes of energy. That energy could, given sufficiently advanced technology, be turned back into us.

In some ways, it is a lesson about our impermanence but it is also a glimpse of our extraordinary gifts. We are matter that began its existence 14 billion years ago as a flash of primordial light. And now, that matter has learned the first step in repeating the process of its creation. For all the conflicts, disasters and alarming election results that human beings generate, we should still be proud of our species.

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 28 May 2014 issue of the New Statesman, The elites vs the people

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Why Twitter is dying, in ten tweets

It's ironic that the most heated discussions of the platform's weaknesses are playing out on the platform itself. 

Twitter has been dying since 2009, and commentators have pre-emptively declared it deceased pretty much every year since. To declare that it's on the downturn has become a bit of a cliché. But that doesn't mean that it isn't also, well, true.

Grumbling among users and commentators has grown to a roar over the past few days, thanks in part to a Buzzfeed report (refuted by Jack Dorsey, Twitter's CEO) claiming the service will move away from a chronological timeline and towards an algorithmic one. Users coined the hashtag #RIPTwitter in response, and, tellingly, many of their complaints spanned beyond the apparently erroneous report. 

They join a clutch of other murmurings, bits of data and suggestions that things are not as they should be in the Twitter aviary. 

Below is one response to the threat of the new timeline, aptly showing that for lots of users, the new feed would have been the straw that broke the tweeters' backs:

Twitter first announced it was considering a new 10,000 character limit in January, but it's yet to be introduced. Reactions so far indicate that no one thinks this is a good idea, as the 140 character limit is so central to Twitter's unique appeal. Other, smaller tweaks – like an edit button – would probably sit much more easily within Twitter's current stable of features, and actually improve user experience: 

While Dorsey completely denied that the change would take place, he then followed up with an ominous suggestion that something would be changing:

"It'll be more real-time than a feed playing out in real time!" probably isn't going to placate users who think the existing feed works just fine. It may be hard to make youself heard on the current timeline, but any kind of wizardry that's going to decide what's "timely" or "live" for you is surely going to discriminate against already alienated users.

I've written before about the common complaint that Twitter is lonely for those with smaller networks. Take this man, who predicts that he'll be even more invisible in Twitter's maelstrom if an algorithm deems him irrelevant: 

What's particularly troubling about Twitter's recent actions is the growing sense that it doesn't "get" its users. This was all but confirmed by a recent string of tweets from Brandon Carpenter, a Twitter employee who tweeted this in response to speculation about new features:

...and then was surprised and shocked when he received abuse from other accounts:

This is particularly ironic because Twitter's approach (or non-approach) to troll accounts and online abusers has made it a target for protest and satire (though last year it did begin to tackle the problem). @TrustySupport, a spoof account, earned hundreds of retweets by mocking Twitter's response to abuse:

Meanwhile, users like Milo Yiannopolous, who regularly incites his followers to abuse and troll individuals (often women and trans people, and most famously as part of G*merg*te), has thrived on Twitter's model and currently enjoys the attentions of almost 160,000 followers. He has boasted about the fact that Twitter could monetise his account to pull itself out of its current financial trough:

The proof of any social media empire's decline, though, is in its number and activity of users. Earlier this month, Business Insider reported that, based on a sample of tweets, tweets per user had fallen by almost 50 per cent since last August. Here's the reporter's tweet about it:

Interestingly, numbers of new users remained roughly the same – which implies not that Twitter can't get new customers, but that it can't keep its current ones engaged and tweeting. 

Most tellingly of all, Twitter has stopped reporting these kinds of numbers publicly, which is why Jim Edwards had to rely on data taken from an API. Another publication followed up Edwards' story with reports that users aren't on the platform enough to generate ad revenue:

The missing piece of the puzzle, and perhaps the one thing keeping Twitter alive, is that its replacement hasn't (yet) surfaced. Commentators obsessed with its declining fortunes still take to Twitter to discuss them, or to share their articles claiming the platform is already dead. It's ironic that the most heated discussions of the platform's weaknesses are playing out on the platform itself. 

For all its faults, and for all they might multiply, Twitter's one advantage is that there's currently no other totally open platform where people can throw their thoughts around in plain, public view. Its greatest threat yet will come not from a new, dodgy feature, but from a new platform – one that can actually compete with it.

Barbara Speed is a technology and digital culture writer at the New Statesman and a staff writer at CityMetric.