A photograph of the Large Hadron Collider in the Science Museum. Photo: Getty
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Entangled in photons: the spooky behaviour of light particles

If you’re after science that makes you question your place in the universe, focus on that phrase “light years”, one that astronomers use so casually.

We are constantly making discoveries that reveal new wonders of the universe. Research presented in June, for instance, shows that some of its most spectacular features, such as the vast towers of gas and dust known as “the Pillars of Creation”, are a result of the way massive stars emit radiation that sculpts nearby gas clouds.

Those pillars are roughly four light years high and 7,000 light years away – which is close, compared to another discovery made recently. Scientists have found three black holes orbiting each other just over four billion light years away.

It’s an extraordinary thing to see things that distant, but in many ways this is just cosmic stamp collecting. These discoveries are informative – breathtaking, even – but they don’t cause you to question your place in the universe.

If that’s what you’re after, focus on that phrase “light years”, one that astronomers use so casually. Herein lies a truly discomfiting mystery.

Light years are a measure of the distance a photon – a packet of light energy – travels in a year. It’s a useful measure because light is the fastest thing in the universe. Yet we are still getting to grips with the properties of photons and it seems that they don’t experience distance in the same way as we do.

Fifty years ago, a Cern physicist called John Bell outlined the weirdness of photons. In a 1964 paper that built on some of Einstein’s work, Bell showed that they defy all ordinary notions of time and space. The phenomenon Bell explored is popularly known as “quantum entanglement”. It involves what Einstein once termed “spooky action at a distance” occurring between two particles. The spookiness begins when we make two photons interact in a way that leaves them entangled – the information about one is partly held in the other. The particles are “complete” only as a pair. Then we keep one on earth while sending the other to, say, the Pillars of Creation. It turns out that we can instantaneously influence the distant photon’s measured properties, such as its direction of spin.

That influence occurs because the spins of an entangled pair of photons are random but linked. You can think of it rather like knocking over two coins that are spinning on their edges. If we poke the one on earth, it might come up heads (entirely at random). If it does, we find, weirdly, that an immediate knock to the other one out there at the Pillars of Creation will give us a tail.

This cosmic connection can’t involve any signals passing between them: it would have to be quicker than light. The only explanation is that photons inhabit a reality beyond the space and time in which we live out our existence.

Entanglement’s delicate nature makes it a kind of tamper-proof seal. In the emerging science of quantum cryptography, entangled photons provide security guaranteed by the laws of physics. Financial institutions already use such measures and we are about to extend the network into space. A team of Italian researchers announced last month that they had bounced photons between satellites and earth without disturbing their quantum properties, laying the groundwork for “quantum communications on a planetary scale”. Here’s the wondrous fact: we are engineering a cosmic network that we may never fully understand. 

Michael Brooks’s “At the Edge of Uncertainty: 11 Discoveries Taking Science by Surprise” is published by Profile (£12.99)

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 02 July 2014 issue of the New Statesman, After God Again

Joshua M. Jones for Emojipedia
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The emojis proposed for release in 2016 are faintly disturbing

Birds of prey, dead flowers and vomit: Emojipedia's vision for 2016. 

Since, as we're constantly being told, emojis are now the fastest growing languge in the UK, it seems only appropriate that its vocabulary should expand to include more commonly used images or ideas as its popularity increases. 

Next year, the Unicode Consortium, which decides which new codes can be added to the emoji dictionary, will approve a new round of symbols. So far, 38 suggestions have been accepted as candidates for the final selection. Emojipedia, an online emoji resource, has taken it upon itself to mock up the new symbols based on the appearance of existing emojis (though emojis are designed slightly differently by different operating systems like Apple or Android). The full list will be decided by Unicode in mid-2016. 

As it stands, the new selection is a little... well, dark. 

First, there are the faces: a Pinocchio-nosed lying face, a dribbling face, a nauseous face, an upset-looking lady and a horrible swollen clown head: 

Then there's what I like to call the "melancholy nighttime collection", including a bat, owl, fox, blackened heart and dying rose: 

Here we have a few predators, thrown in for good measure, and a stop sign:

There are a few symbols of optimism amid the doom and gloom, including a pair of crossed fingers, clinking champagne glasses and smiling cowboy, plus a groom and prince to round out the bride and princess on current release. (You can see the full list of mock-ups here). But overall, the tone is remarkably sombre. 

Perhaps as emoji become ever more popular as a method of communication, we need to accept that they must represent the world in all its darkness and nuance. Not every experience deserves a smiley face, after all. 

All mock-ups: Emojpedia.

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