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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Welcome to the new New Statesman website

We've had a makeover. We hope you like it!

In the past five years, the New Statesman website has grown beyond all our expectations. In 2010, barely half a million readers a month were visiting it; now, we regularly see around two million people. The way we read on the internet has changed in that time, too – more than half the people looking at our website are now doing so using a mobile phone or a tablet rather than their desktop computer. 

To reflect this shift, we have launched a new New Statesman website. The design is simple, clean and readable, as well as being optimised for screens small and large. There is a greater emphasis on images and typography. We have made the navigation more intuitive, so that it will be easier for you to find the features, columns and reviews you enjoy in the magazine online, as well as our web-only offering of fast-paced Westminster coverage, cultural comment and opinionated blogging. Above all, it is a place for reading, free of distraction and interruption.

The credit for the new website's design should go to New Statesman's development team - Sam Hall, Chris Boyle and Zoltan Hack (Chris even designed us a cute 404 page), with input from our design editor Erica Weathers. As you might have noticed, we are now using one of our magazine fonts (Unit Slab) for headlines, plus a body type that's similar to Documenta (Merryweather). 

On the editorial side, the project was led by our web editor Caroline Crampton, who spent many hours puzzling over the perfect taxonomy. Her attention to detail has been incredible. If you would like to give us any feedback, email me or Caroline on firstname.lastname@newstatesman.co.uk

So far, it's looking great - we've tripled the number of pages per visit, and increased dwell time on articles. But any update means that some features won't work quite how they used to, so here's a quick guide to what's new.

1. Our new homepage

The new front page is now mobile-optimised, and responsive across tablet and desktop. We're still fine-tuning it, but for now we're keeping things simple: a splash, three stories of the day, and better display for our popular Westminster-focused blog, the Staggers, edited by Stephen Bush. Further down, you'll find a mix of magazine and web-first content, plus links to our most popular stories, our podcasts, and our sister site CityMetric, edited by Jonn Elledge.

On mobile, we've stripped back the homepage - so if you want more options, then click the "hamburger" in the top right to see the full menu.

 

2. A longreads section

We now have a dedicated section for magazine features, and a special template for them, too. This means a much less cluttered reading experience, with more white space - perfect if you are settling down for 6,000 words on the menopause by Suzanne Moore, or the blockbuster last interview with Christopher Hitchens by Richard Dawkins

3. This Week's Magazine

We wanted to give a better sense of what's in the magazine every week, so we've created a dedicated page (here is last week's, Isis and the new barbarism, and here is this week's, Pope of the masses). You can click the arrow and cycle through past covers, to get a sense of the breadth of our interests. You can now see what's in every section, and which pieces are available online. As a rule, we currently publish the leader and columns online in the week of print publication, but reviews and articles are held back for up to seven days. That means the best way to get all our magazine content as soon as possible is to subscribe to the magazine, in paper form, on Kindle or iPad.  

4. Comments

We've disabled comments for launch as the unit can be unpredictable, but they'll be back soon. You'll need to click to expand them at the bottom of stories (otherwise they would have interfered with the infinite scroll - which allows you to move on to another story once you've finished reading the first one). 

5. Our writers

For 102 years, of our biggest strengths has always been our world-class writers - from HG Wells to Rebecca West to Martin Amis and Christopher Hitchens. We've now created a dedicated page where you can see our regular writers, both in print and online, and find links to their entire archives. 

6. Podcasts

As well as the main New Statesman podcast - which offers politics, culture and foreign affairs - Caroline Crampton and Anna Leszkiewicz have recently launched SRSLY, a podcast which takes pop culture seriously. Recent topics include fandom, graphic novels and the politics of Harry Potter. You can subscribe here, and follow SRSLY on Twitter.

7. The Staggers

We've introduced a new unit on the homepage next to the splash, for the latest stories, and you can find the our rolling politics blog The Staggers underneath it. There's room on the homepage to display the three most recently published politics articles, so if you want a more in-depth look at the day's politics coverage, bookmark The Staggers' dedicated homepage

Anyway, we hope you like the new look - any feedback, drop me or Caroline a line by email or on Twitter.

Helen Lewis is deputy editor of the New Statesman. She has presented BBC Radio 4’s Week in Westminster and is a regular panellist on BBC1’s Sunday Politics.