Egos and intensity in the search for dark matter

Voices in the dark.

In the next few weeks, the world’s most sensitive dark matter detector will begin its operations under Italy’s Gran Sasso mountain. This seems a good time to point out that it is sharing the mountain with a detector that may already have found some. What a shame, then, that what might one day be viewed as a historic result has been mired in petty name-calling.

We’ve been looking for dark matter since 1933, when the astronomer Fritz Zwicky pointed out that clusters of galaxies move in ways that seemingly defy the laws of physics. The movement made sense only if the clusters were experiencing a gravitational pull from some invisible stuff nearby.

For various reasons, mostly to do with other astronomers not liking Zwicky very much, we’ve been searching for dark matter seriously only since the 1970s. During those four decades, there has been a series of pronouncements about its discovery being only a decade away. It might now be time to take those pronouncements a little more seriously: lately, the sensitivity of detectors has been improving tenfold every two years. We must surely be on the verge of finally nailing down the existence of dark matter. If we haven’t already, that is.

Dark matter doesn’t just hold gravity clusters together – it’s everywhere. It’s right here on earth, for instance: billions of dark matter particles fly through your body every second. You won’t feel them and they won’t harm you. They don’t interact much with the stuff of our everyday reality, which is what has made them so hard to detect.

While we don’t have any concrete detections of single particles, we do seem to have a discernible signal from passing through clouds of dark matter. It was first spotted by the DAMA dark matter detector, which is based, like the new DarkSide-50 detector, deep under the mountains at Gran Sasso. The rock covering them protects the instruments from distracting sources of noise.

In 2008, DAMA’s operators announced that they had identified a signal that rose and faded with the seasons. It might have been ignored, except that this is exactly what Katherine Freese predicted for a dark matter signal in 1986. She said that the intensity of dark matter detections should depend on the time of year, because as the earth whirls round the sun and the sun moves through the Milky Way, the amount of dark matter hitting the detectors will ebb and flow. It’s rather like the difference between walking into wind-driven rain, then turning and walking the other way. In June, dark matter hits Planet Earth full in the face; in December, it’s at our back.

So, it was pretty exciting that DAMA’s detector saw this predicted pattern. It was even more exciting when another detector, CoGeNT, based in a deep underground mine in Minnesota, also saw it. It’s a shame that a third detector, Xenon, didn’t.

Xenon is also in the Gran Sasso mine and there is no love lost between the leaders of these two research efforts. CoGeNT’s Juan Collar has called Xenon’s science “pure, weapons-grade balonium”. Not content with antagonising his peers, Collar has also accused the DAMA project of “cheapening the level of our discourse to truly imbecilic levels”.

Finding dark matter is proving to be astonishingly difficult and everyone knows there’s a Nobel prize at stake, so it’s not surprising that the claws are out.

Anyway, welcome to the fray, DarkSide-50; there is definitely room for more players in this competition. Whether there is room for more egos, however, is another matter.

Inside the DarkSide-50 experiment.

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 18 February 2013 issue of the New Statesman, Iraq: ten years on

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Buying into broadband’s bigger picture

Reliable internet access must be viewed as a basic necessity, writes Russell Haworth, CEO of Nominet.

 

As we hurtle towards a connected future, in which the internet will underpin most aspects of our daily lives, connectivity will become a necessity and not a luxury. As a society, we need to consider the wider benefits of enabling internet connections for all and ensure no corner of the county is left out of the digital loop.

Currently, despite government incentive schemes and universal service obligations, the rollout of broadband is left largely to the market, which relies on fixed and wireless network operators justifying deployment based on their own business models. The commercial justification for broadband deployment relies on there being sufficient demand and enough people to pay for a broadband subscription. Put flippantly, are there enough people willing to pay for Netflix, or Amazon? However, rather than depending on the broad appeal of consumer services we need to think more holistically about the provision of internet services. If road building decisions followed the same approach, it would equate to only building a road if everyone living in the area bought yearly gym membership for the leisure centre at the end of the new tarmac. The business case is narrow, and overlooks the far-reaching and ultimately more impactful benefits that are available.

Internet is infrastructure as much as roads are, and could easily prove attractive to a wider range of companies investing in digital technology who stand to gain from internet-enabled communities. Health services are one of the most compelling business cases for internet connectivity, especially in remote, rural communities that are often in the “final five per cent” or suffering with below average internet speeds. Super-fast broadband, defined as 30 Mbps, is now available to 89 per cent of UK homes, but only 59 per cent of rural dwellings can access these speeds.

We mustn’t assume this is a minority; rural areas make up 85 per cent of English land and almost ten million people (almost a fifth of the population) live in rural communities. This figure is rising, and ageing ‒ on average, 23.5 per cent of the rural population is over 65 compared to 16.3 per cent in urban areas ‒ and this presents complicated healthcare challenges for a NHS already struggling to meet demand. It goes without saying that accessibility is an issue: only 80 per cent of rural residents live within 4km of a GP’s surgery compared to 98 per cent of the urban population.

While the NHS may not have the resources to build more surgeries and hospitals, robust broadband connections in these areas would enable them to roll out telehealth options and empower their patients with healthcare monitoring apps and diagnostic tools. This would lower demand on face-to-face services and could improve the health of people in remote areas; a compelling business case for broadband.

We can’t afford to rely on “one business case to rule them all” when it comes to internet connectivity – the needs run far beyond Netflix and Spotify, and the long-term, economic and social benefits are vast. It’s time to shift our thinking, considering internet connectivity as essential infrastructure and invest in it accordingly, especially when it comes to the needs of the remote, rural areas of the country.

Russell Haworth joined Nominet as CEO in 2015. He leads the organisation as it develops its core registry business, explores the potential of new technologies in the global internet sector, and delivers on its commitment to ensuring the internet is a force for good.

This article was taken from a New Statesman roundtable supplement "The Internet as Infrastructure: Why rural connectivity is crucial to the UK’s success"

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