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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7 adorably wrong retro visions of the future

With the future looking gloomier than ever, let's take a look at what could have been.

Ah, the future. The golden, glorious future. A time when food will be replaced by pills, walking will be replaced by hovering, and someone will have finally invented a printer that will print your black and white theatre ticket even though (even though!) you have an empty magenta ink cartridge. Who can wait? 

Unfortunately, what with the end-of-the-world-as-we-know-it (see: Trump, Donald J) the future seems less and less spectacular everyday. Is it time to build an underground bunker? Who can say? I can. The answer is yes.

But while you're waiting for your Spaghetti Hoops to heat up in your concrete hidey-hole, you'll need something to read. Here are seven futures that we could have had, if it wasn't for fascism (and also, I guess, the fact that some of these are really dumb).

1. Commuter helicopters

Popular Mechanics (1951) via Flyingcarsandfoodpills.com

What they predicted: Personal helicopters which would transform commuting forever. 

Why it didn't happen: Because apparently Future Us are sufficiently advanced enough to create mini, personal helicopters, but not smart enough to have grasped the concept of a helipad. 

2. Instantly-cookable food

Via Reddit u/Jaykirsch

What they predicted: Food that can be heated or chilled instantly within its packet, by the turn of a knob.

Why it didn't happen: Remember in 2005 when Walkers Worcester Sauce crisps were recalled because it was thought they'd give you cancer? Yeah, that. 

3. Space puppies

Amazing Science Fiction (1958) via Pulparchive.com 

What they predicted: Space puppies. Puppies in space.

Why it didn't happen: Because God enjoys our pain.

4. The "Dinosaur Truck" elevated bus

The Practical Science For Boys And Girls (1949) via Darkroastedblend.com

What they predicted: Buses that could seamlessly glide over cars, carrying us onwards to a new and better future.

Why it didn't happen: It did! China have it. Well done China.

5.  A radio that prints newspapers

Radio Craft (1934) via Tarzan.org

What they predicted: A radio that could print out your morning newspaper, with some kind of nice little red thing on top.

Why it didn't happen: All media is obsolete. You are not even reading these words. Unless you're my mum. Hi mum. 

6. A robot that hits children on the head if they don't listen in class

Computopia (1969) via Pinktentacle.com

What they predicted: A robot that hits children on the head if they don't listen in class.

Why it didn't happen: Whilst our robotics are advanced enough, it turns out so too are our morals. Bummer.

7. Wrist computers

Byte (1981) via archive.org

What they predicted: Little computers that will sit on your wrist, like a watch.

Why it didn't happen: You might be gaping and gawping that someone in 1981 successfully managed to predict the Apple Watch, but you'd be wrong. Take another look - see that tiny keyboard? No one could use that tiny keyboard. What were our ancestors thinking? Idiots. 

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