Dark skies: a view of the milky way during a meteor shower, Myanmar. Photo: Getty
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Dark energy vs dark matter: a battle of two cosmic monsters

Michael Brooks’s Science Column.

It might be the most prestigious journal in physics, but the Physical Review Letters is no good at teasers. Early in November it published a paper entitled: Indications of a Late-Time Interaction in the Dark Sector. Hardly a great headline for what should have been, in the style of Alien v Predator, “Dark Matter v Dark Energy” – a story of two cosmic monsters locked in eternal conflict.

We believe these monsters exist, but we haven’t seen either of them and we know very little about them. We have suspected the existence of dark matter since 1933, when a Swiss astronomer noticed something odd about the way galaxy clusters spin. They looked like they were being held together by the gravitational pull of invisible matter, which he duly named dark matter. We have been trying to see the stuff ever since, to no avail.

Dark energy is a more recent idea. It, too, comes from astronomical observations, this time of supernovae. A 1998 analysis of the light from these stellar explosions suggested that not only is the universe expanding, but this expansion is getting faster all the time. That can only happen with the help of energy from some unknown source – hence dark energy.

Together, dark energy and dark matter make up 96 per cent of the universe. Now, it turns out, dark energy may be consuming the dark matter.

The discovery came from more observations: this time, of the rate at which cosmic structures form. Dark matter seeds galaxy formation, but galaxies aren’t forming as fast as we would expect. This would make sense if dark matter were disappearing from the universe, but various straightforward explanations for why that might occur have failed to correspond with the observed facts. Now a team of British and Italian researchers has created a computer model that does match the observations. Critical to its success is the idea that dark matter is slowly being converted to dark energy.

According to the simulation, the ingestion of dark matter would be a relatively recent phenomenon, beginning roughly eight billion years ago. If it is really happening, it is important to understand, because our attempts to chart the history of the universe depend on dark matter’s role in forming cosmic structures.

Working from observations of the cosmic microwave background radiation, which came into being roughly 300,000 years after the Big Bang, researchers have shown that the radiation’s distribution through the universe would have seeded long filaments of dark matter. The gravitational pull of these filaments attracted the first atoms of normal matter, gradually creating stars and galaxies in long strings. This is the kind of structure we see now.

Yet if dark energy is slowly taking over from dark matter our previous calculations of cosmic history will have to be corrected. And intriguingly (spoiler alert), it will change our predictions. If dark energy is consuming dark matter, the universe will become dominated by dark energy more quickly than previously thought. That will precipitate an inglorious finale in which dark energy’s repulsive power pushes everything interesting away from us.

Eventually, all the other galaxies will be so far away, and receding so fast, that their light will never reach what remains of our Milky Way. Nearby stars will burn out. Our sun is expected to end its life as a huge single crystal of carbon: a dark diamond in the sky, with no surrounding starlight to make it sparkle.

Afterwards, all the atoms will drift apart and then the fundamental particles of matter will slowly decay to nothing. It’s not a Hollywood ending, but don’t complain that you weren’t warned. 

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 November 2014 issue of the New Statesman, The rise of the insurgents

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“There will be an absolute meltdown in 2020” : what’s holding back the introduction of electronic voting?

The government's reluctance to implement electronic voting will affect our future, and in – the case of Brexit – may have already dramatically affected our past. 

Imagine, just for a second, that the situation was reversed. Imagine if, for a hundred years, we had scanned, swiped, and tapped our votes into a secure, fool-proof electronic system and someone waddled along and said, “Alright lads, how about we try pencil and paper?”. How about we desperately try to find a spare hour to shuffle to the village hall in the rain and scratch an “X” onto a scrap of paper with a stubby bit of lead, and then let a volunteer named Deidre count it at two am? What could possibly go wrong?

If you picture this scenario – posited by my colleague Anna – then it quickly becomes clear how ridiculous it is that the UK has not yet implemented electronic voting in any lasting way, shape, or form. Not only are we not on board with popping online to vote, we’re also reluctant to use technology when it comes to marking our ballots, authenticating voters’ identities, and counting votes. Despite the success of electronic voting in countries such as Brazil, Estonia, and India, the UK continues to reject reform. Why?

 “I think the problem is political at the moment,” says Mike Summers, the program manager at Smartmatic, an electronic voting company who have run three national elections in the Philippines, have a 15 year contract with Belgium, and have counted around 3.7 billion electronic votes in 12 years. “I think there is a fear that if you enfranchise groups of younger people, then you don’t necessarily know how they’re going to vote.”

We can, however, make a pretty good guess. Smartmatic’s own research shows that 57 per cent of 18-24 year olds would be more likely to vote if they could do so online and 55 per cent said they would have used online voting at the last general election. As Labour's vote share could have been boosted at the last election if only more young people had turned out to vote, this might make electronic voting an uninviting prospect for Theresa May.

“Prior to the last parliamentary election the Labour party were vehemently in favour of electronic voting,” says Summers. “Things are moving very slowly compared to other developing and developed nations so our reading of the situation is that it’s a largely political one.”

The consequences of this inaction are severe. Holding off on a voting system that provides greater accessibility to all compromises the very notion of democracy, but it also has potentially more immediate repercussions. “In 2020 everything is going to hit the proverbial fan we’re going to be a laughing stock,” says Summers.

The reason for this is because of the wide array of elections sheduled for 2020. Not only will there be a general election, there are also police and crime commissioner elections, the London Assembly and the London mayoral elections, and also local elections. “There is real concern that because of the complexity of this event there is going to be an absolute meltdown.”

Electronic voting would help prevent such a meltdown by ensuring, among other things, that voters couldn’t accidentally mark a first past the post ballot with a preferential voting system (or vice versa), that votes could be counted faster, and that overseas votes would not be lost in the post. The last is of particular importance as the government are now planning to scrap the 15-year rule that bans long-term expatriates from voting in UK elections.

“That’s a potential five million additional expats who will be eligible to vote,” says Summers, “How are you going to service them?” The answer to that is via the postal vote, and the limitations of this traditional method make the case for electronic voting even stronger.

“Postal voters authenticate themselves with a signature – mine is easily forgeable – and their date of birth,” says Summers. “The traditional methods are not secure. With online voting we can use facial biometrics to compare a person’s digital facial portrait – a selfie, if you like – with their ID, and we can verify there is a match.

“The next problem is security, and putting your ballot in an envelope is not secure. We have very, very strong application level cryptography. The moment a voter casts their ballot we encrypt it on the voting side and digitally sign it as a method of proving the integrity. Additionally, when postal voters put their vote in the post box they have no way of checking it was received or counted, so you have no verifiability. We have a number of tools that voters can use to verify their vote was received and was included in the final tally.”

Nowhere is the importance of the postal vote clearer than in the case of Brexit. “You could argue that the outcome would have been different,” says Summers. “Lots of expats voted by post and a lot of the votes didn’t come back before the close of the election count. We have an office in Amsterdam and one of the guys plays in a local rugby club in The Hague. There are ten Brits on that team and six of them received their postal vote after the close of the election. If you’re an expat living overseas then are you going to vote for or against Brexit? If those voters had voted then the outcome could have been completely different.”

Yet the benefits of accuracy, transparency, verifiability, and accessibility are easily side-lined by one bloodcurdling word. Hackers. If Hillary Clinton’s emails can become your bedtime reading, isn’t it possible – nay, probable – that elections will be hacked, falsified, and corrupted?

“The easiest election to hack is a paper election,” says Summers. “It is important to educate people on the difference between election information systems, which the DMC use, and voting systems. The protections of voting systems are above and beyond anything you will use in any other online application, including online banking and ecommerce solutions.”

As a representative of Smartmatic, Summers would say this, but they and other companies have created a wide variety of solutions which – even if imperfect – are vulnerable to fewer mistakes than Deidre in the village hall. Even if there are flaws, it seems important to iron these out now – before 2020 – to ensure the success of electronic voting in the future.

Although the House of Commons’ Commission on Digital Democracy recommended that the UK should adopt electronic voting by 2020, there is little evidence that steps are being taken towards this goal. “I’d love to turn around and say I think steps are being taken but there is a lack of willingness to acknowledge the shortcomings that we have in terms of UK elections,” says Summers. For now, then, the debate rages on. Should we stick to the tried-and-tested, or should we transform the electoral process forever? I know – let's vote on it. 

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