Sunday, November 21, 2010

CERN traps antimatter atoms

It looks like the doomsday sayers were wrong - creating antimatter didn't destroy the planet (or was it the universe?). That's hardly surprising, as antimatter pops in and out of existence all the time, and both the universe and the planet seems to still be here.

CERN has created antimatter for nearly a decade, starting in 2002, but these particles have always been short-lived as the interact with the matter around them, and disappears.

This week, however, Nature published the news that scientists at CERN has managed to contain antimatter atoms, for more than 170 milliseconds, 38 times. This was done by using a "magnetic trap"

The ALPHA claim is the first major advance since the creation of thousands of antihydrogen atoms in 2002 by a forerunner experiment called ATHENA2 and by ATRAP3 [...]. Both experiments combined decelerated antiprotons with positrons at CERN to produce antihydrogen atoms. But, within several milliseconds, the atoms annihilated with the ordinary matter in the walls of their containers.

To prevent that from happening, the ALPHA team formed antihydrogen atoms in a magnetic trap. Although not electrically charged like antiprotons and positrons, antihydrogen — like hydrogen — has a more subtle magnetic character that arises from the spins of its constituent particles. The ALPHA researchers used an octupole magnet, produced by the current flowing in eight wires, to create a magnetic field that was strongest near the walls of the trap, falling to a minimum at the centre, causing the atoms to collect there.

Creating antimatter atoms this way has proven to be much more difficult than the "traditional" way

To trap just 38 atoms, the group had to run the experiment 335 times. "This was ten thousand times more difficult" than creating untrapped antihydrogen atoms, says Hangst — ATHENA made an estimated 50,000 of them in one go in 2002. To do spectroscopic measurements, Surko estimates that up to 100 antihydrogen atoms may need to be trapped at once.

Obviously, there is some work yet to be done before measurements can be made, but according to this National Geographic article, great advances have been made since the Nature article

Since the experiments covered in the Nature study, the researchers have created many more antihydrogen atoms and held them for much longer—fodder for a future report.

According to Fajans, "We're doing much better now."

If more antihydrogen atoms can be produced and trapped for longer periods, scientists might finally be able to study them in enough detail to explain their scarcity in our universe, he added.

That's a pretty big deal. Let's hope that the progress continues.

For the original paper, you can find it behind Nature's pay-wall here

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Are skepticism and atheism non-overlapping magisteria?

Ever so often a fight breaks out among skeptics and/or atheists about how to deal with religious people. This time it was started by Jeff Wagg who is criticizing the skeptic conference Skepticon3 for being too atheistic. The organizer of the conference, JT Eberhard has responded (pretty well in my opinion) as has PZ Myers, who is a speaker on the conference.

Now, I make no bones about being both a skeptic and an atheist, so it is easy for me to just side with Eberhard on this, and dismiss Wagg out of hand. But would it be right? Looking at the comments to Wagg's original post, you'll notice some fairly prominent skeptics siding with him. It might be one thing to dismiss Wagg, a person who has flirted with anthropogenic global warming denial in the past, but I'll be damned if I am going to dismiss Eugenie Scott without serious consideration.

So, is atheism and skepticism non-overlapping magisteria, as Gould famously said about science and religion?

The short answer to that is NO. The longer answer is, on the other hand, more complex. Skepticism can be said to be a method, while atheism is a position related to a specific subject (the belief in the existence of deities). Skeptics are people who apply skepticism to all subjects, while atheists are simply people who don't hold a belief in a deity.

The group of atheists and skeptics are overlapping, but neither is by any means a subset of the other. Many, probably even most, skeptics are also atheists, but there are many skeptics who are still religious - some by not applying skepticism on that particular part of their lives, others by accepting that their faith flies in the face of evidence. Atheists, on the other hand, are often not skeptics.

Personally, I think that atheism is a natural result of skepticism (and it is interesting to note that the skeptics involved in this conversation are, to the best of my knowledge, all atheists).

So, what's my point? Well, what I am getting around to, is that Wagg might be right that a skeptic conference focused overly much on skepticism towards religion might be off-putting to some skeptics. But so what? There are global warming deniers showing up in all skeptic groups that I've come across - should we pretend that they are right? Or should we avoid the subject? Or course not. For skepticism to make sense, we have to apply it to everything.

This doesn't mean that we have to do it all the time, so if Wagg wants a skeptic conference that doesn't touch the subject of religion, that's great - he should go ahead and create it. Then the rest of us will choose whether we want to participate or not. If it is about ghost hunting, UFOs and cryptozoology, I'll personally give it a pass, but if it, on the other hand, is about woo and alternative "medicine", I'd be interested.

What Wagg shouldn't do, however, is to tell other people how to run their conferences, nor should he try to exclude subjects from being covered by skepticism. All subjects must be open to skeptical inquiry. Otherwise, how will we expand out knowledge and understanding of the world?

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Thursday, November 04, 2010

Call for submissions - best skepticism of 2010

I am planning on making a Skeptics' Circle style of post highlighting the best skepticism of 2010, but in order to do that I need some help - simply put, the skeptic presence on the internet has become too vast for one person to keep track of it all, and I would love to get some submissions for the post.

The scope of the post would be more broad than for the Skeptics' Circle - instead of just blog posts, I'd also welcome podcast episodes, videos and news articles of relevance. I'd also like links to new organizations, podcasts, and blogs started in 2010. Heck, even court rulings of relevance would be appreciated.

So, if you have something which you think might just fit into what I've described, please don't hesitate to send it to me (kriswager at gmail dot com), and I'll take a look at it. Please include the word "skeptic" somewhere in the mail title, so I can easily spot it if it gets caught by the spam filter.

The plan is that this post will be going up around Christmas, but please submit anything you already have as soon as possible. It will take some time to go through all the material, especially if there are many podcast episodes and YouTube videos.

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