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

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YouTube announces new measures against extremism – but where do they leave the far right?

Videos by alt-right commentators have arguably radicalised many online. Will Google's latest policies do anything to change this?

Within hours of the terrorist attack in Finsbury Park, Tommy Robinson was trending on Twitter. The former leader of the English Defence League accused the Finsbury Park mosque of “creating terrorists” in a series of tweets on his personal account.

More than 17,400 people have now tweeted about the 34-year-old, with many theorising he could have radicalised the attacker who allegedly shouted “I’m going to kill all Muslims” at the scene. At present, there is no evidence that the man arrested by police on suspicion of attempted murder is a fan of Robinson.

“People are saying I’m inciting hate,” said Robinson in a video uploaded to Twitter and YouTube after the attack. “I just tell the facts and the truth and I’m not going to apologise for that…

“If giving you quotes from the Quran that incite murder and war against us is inciting hate, I’m guilty. If telling you all the problematic problems that come from the teachings and scriptures of Islam, I’m guilty. But these are just facts.”

After describing the country as being at “war”, he goes on to say: “Please one person, just one, give me one example of me inciting hate.”

When we talk about radicalisation and terrorism, we are finally to understand that this extends beyond the work of Isis.

Just over a year ago, Labour MP Jo Cox was murdered by a white supremacist. This morning, Harry Potter author JK Rowling used Twitter to accuse columnist Katie Hopkins of contributing to radicalisation. The New Statesman’s own Media Mole notes how right-wing tabloids incite hate.

In particular, it is now evident how the far right radicalises online. In December 2016, a man fired three shots in a Washington DC pizza parlour that the alt-right (on 4Chan and YouTube) had accused of being at the centre of a paedophile ring.

The internet arguably allowed Anders Breivik, the Norwegian far right white supremacist who killed 77 people in 2011, to cultivate his extreme views. Alexandre Bissonnette, the white nationalist who murdered six men at a Québec City mosque in January, was described by many as an “internet troll”.

Earlier this year, a report by the Commons home affairs committee accused social media giants of not doing enough to tackle terrorism online. In response to this – and following a series of high-profile brands pulling their advertising from YouTube after it was featured on or by terrorism-related videos – Google, which owns the video-sharing site, has now announced four steps it is taking to fight online terror. But do these reflect the reality that there are many forms of extremism?

Google’s new guidelines speak of “terrorism” and “extremism” in broad terms. This means that videos glorifying or inciting terrorism will be treated the same whether they are from the far right, far left, or pro-Isis organisations.

Google’s four steps for tackling such videos include: using machine learning to identify videos glorifying violence, using a team of human flaggers to identify problematic videos, and using a "redirect method" to send potential Isis recruits towards anti-terror videos. Each of these steps is concerned with content that either breaks the law or violates YouTube’s policies.

The fourth step (or rather the third, as it is ordered in Google’s blogpost) is focused on non-illegal, non-policy violating content. For example, this could include videos that don’t directly incite terrorism, but arguably incite hate, such as those denying the Holocaust.

According to Kent Walker, Google’s general counsel, these could also be “videos that contain inflammatory religious or supremacist content”. Rather than being removed like the other offending videos, these will be hidden behind a warning, not have adverts on them (therefore preventing their creators from making money), and will not be eligible for comments. Essentially, as Walker writes, “that means these videos will have less engagement and be harder to find”.

It remains to be seen whether – or how – this will apply to the content of Tommy Robinson. YouTube’s steps will be taken on a video-by-video basis, meaning no far right commentator will be banned outright. Instead, YouTube simply won’t promote any offending videos, meaning they will not appear in their subscribers’ recommended feeds and will be difficult to find on the site.

In this way, Google has remained committed to free speech while doing more to tackle extremism on YouTube. Those like Robinson who claim to just “tell the facts” could arguably now be held to account for their actions. Many on the far right are careful to not explicitly advocate violence. Nevertheless, the loaded language used in their videos could arguably incite hate.

Paul Joseph Watson, a right-wing conspiracy theorist YouTuber with nearly one million subscribers, has never advocated terrorism, but has videos entitled “Islam is NOT a Religion of Peace” and “Chuck Johnson: Muslim Migrants Will Cause Collapse of Europe”.

In the past I have argued that allowing Google and YouTube to censor us in the name of “extremism” and “terrorism” is a troubling trend, but with these new promises, the company has walked the delicate line between the law and free speech. By allowing hateful, but not illegal, content to be hosted on its site and yet restricted from a wider audience, YouTube is taking a stand against extremists of all kinds.

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

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