Neutrinos may not be neutral after all!

Do neutrinos affect radioactive decay? That's what new research at Purdue seems to suggest. When researchers at Purdue were looking for a reliable way to generate random numbers, they thought they were smart to use radioactive decay - after all the rate of decay was a known constant (for a given material) but the decay of any particular atom was truly random. But what they discovered may have huge implications for the Standard Model, for physics and for cosmology.

As the researchers pored through published data on specific isotopes, they found disagreement in the measured decay rates – odd for supposed physical constants. Checking data collected at Brookhaven National Laboratory on Long Island and the Federal Physical and Technical Institute in Germany, they came across something even more surprising: long-term observation of the decay rate of silicon-32 and radium-226 seemed to show a small seasonal variation. The decay rate was ever so slightly faster in winter than in summer.
In addition, during a solar flare event in Dec 2006, a Purdue researcher, observing day in manganese-54, noticed that the decay rate began to drop almost 36 hours before the flare event became visible on earth. In a series of published papers, the Purdue team showed that the observed variations in decay rates were highly unlikely to have come from environmental influences on the detection systems. Their findings strengthened the argument that the strange swings in decay rates were caused by neutrinos from the sun. The decay rates dropped as the Earth came closer to the sun (where it would be exposed to more neutrinos) and rose as the Earth moved farther away. So there was good reason to suspect the sun, but could it be proven? Enter Peter Sturrock, Stanford professor emeritus of applied physics and an expert on the inner workings of the sun. Sturrock knew from his experience that the observed neutrino intensity varies on a regular basis as the sun revolves and shows a different face to the Earth. He suggested that Purdue: Look for evidence that the changes in radioactive decay on Earth vary with the rotation of the sun. Looking again at the decay data from the Brookhaven lab, the researchers found a recurring pattern of 33 days, which differed from the observed solar rotation period of about 28 days. They explain this by suggesting that the core of the sun – where nuclear reactions produce neutrinos – spins more slowly than the surface. The evidence points toward a conclusion that emissions form the sun are directly influencing radioactive isotopes on Earth. However, no one knows how neutrinos could interact with radioactive materials to change their rate of decay. This result holds promise in many ways: as an early warning system for Solar Flares; as an avenue for new research on neutrinos; or as the first inking of even stranger new particles. “It would have to be something we don’t know about, an unknown particle that is also emitted by the sun and has this effect, and that would be even more remarkable,” Sturrock said. H/T: io9 and Symmetry Magazine

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Animal cultures and overimitating

In the July 16, 2010 edition of Science (available online only to subscribers), Michael Balter opens his article, "Probing Cultures Secrets," with words that would have been considered blasphemous by scientists only a few decades ago:

Scientists once designated "culture" as the exclusive province of humans. But that elitist attitude is long gone, as evidenced by the recent meeting here on how culture, usually defined as the passing on of traditions by learning from others, arises and changes. The 700 attendees [of "culture evolves," held in London], a mixture of researchers and members of the public, heard talks on cultural transmission in fish, meerkats, birds, and monkeys, as well as in extinct and living humans.

Balter's question is "why do certain cultural trends, such as fashions, begin and catch on? To illustrate his answer, Balter refers to the work of anthropologist Susan Perry who described some unusual behavior of white faced capuchin monkeys in Costa Rica. Balter writes that some of these monkeys have adopted various traditions with "no clear survival purpose, such as sniffing each other's fingers and inserting them into a companions nose, or biting off a big chunk of another monkeys for and holding it in the mouth while he or she playfully tries to get it back."

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Real life mind meld

Michael Balter reports that scientists are honing in on the real-life mechanism that allows two minds to meld during conversation:

Scientists have traditionally considered talking and listening to be two independent processes. The idea is that speech is produced in some parts of the brain, including a region known as Broca's area, and understood in others, including a region known as Wernicke's area. But recent studies suggest that there's actually much more overlap. For example, partners in a conversation will unconsciously begin imitating each other, adopting similar grammatical structures, speaking rates, and even bodily postures. This overlap helps people establish a "common ground" during conversation and may even help them predict what the other is going to say next . . . Some researchers think that so-called mirror neurons, which fire when one individual observes the actions of another, might be involved in these interactions.
The scientists conducting the study argue that the experiments they've conducted demonstrate that listeners are active participants to successful conversations.

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Zooming in on the beach

Earlier, I posted on Powers of Ten. I've long been fascinated by the way numerous relatively similar things can aggregate into macro patterns such as the crisscross that you can see in the photo to the right. Naturally occurring pattern like this abound on the beach.

How is it that sand dunes can naturally form out of random sand grains and random wind? Just because it's difficult to explain doesn't mean that it doesn't happen, of course.

The warm-up act of this post consists of three photos I recently took on a beach. First you see the "sand," then you focus in to see the individual grains of sand. Every one of those grains is different, even though they each look the same from a distance. They are a lot like people in that regard.

The above photos are mere warm up act for this wonderful, mind-stretching display of smallness and largeness. I realize that I featured this display in an earlier post, but it is that well done.

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