You've Got Some Explaining to Do

Electric Material in Mantle Could Explain Earth’s Rotation

Well, not really. The electric material could explain some of the small variations in the Earth’s rotation. Not quite the same thing.

Earth’s spin isn’t flawless. Geophysicists have discovered that the time it takes our planet to complete one rotation—the length of a day—fluctuates slightly over the course of months or years. They’ve also noticed extra swing in the predictable wobble of Earth’s axis of rotation, like the swaying of a spinning top. The variations are probably caused by the solid iron inner core, liquid metal outer core, and rocky mantle rotating at slightly different rates. Friction helps bring them into line, and the magnetic field of the outer core can pull on the metal inner core. But to really fit the observations, the core should also exert its magnetic tug on the mantle, says Bruce Buffett, an earth scientist at the University of California, Berkeley, who was not involved in the new study. This means that a layer of the mantle must be able to conduct electricity. But, he says, “the origin of the metallic layer remains an open question.”

What She Said

why i’m terrified (but excited) about science online 2012

All of the pre-#scio12 chatter has picked up in recent weeks, and now that we’re entering the final countdown, I’m (thankfully) recovered enough from a nasty respiratory infection to tune in again. The problem is that tuning in at all is like a highly addictive drug: I get a taste and I want more. You people are going to make me into a junkie.

I, too have been distracted by an illness (a nasty cold) and am just emerging to deal with all the last-minute details of going to ScienceOnline2012. I’m excited because last year was a lot of fun and this year promises even more. Last year pumped me up, blogging-enthusiasm-wise, and it lasted for a few months. So I’m looking for that same kind of score this year.

Because of my cold I don’t have posts in the queue yet, and I don’t expect to have a lot of free time, so things may go quiet.

Just Giving it Away

One the heels of my recent discussion of the value of information trading (as opposed to deception) to research, I read about a push for even more access to this information: Scientists, Share Secrets or Lose Funding: Stodden and Arbesman

Many people assume that scientists the world over freely exchange not only the results of their experiments but also the detailed data, statistical tools and computer instructions they employed to arrive at those results. This is the kind of information that other scientists need in order to replicate the studies. The truth is, open exchange of such information is not common, making verification of published findings all but impossible and creating a credibility crisis in computational science.

Inadequate sharing is common to all scientific domains that use computers in their research today (most of science), and it hampers transparency.
By making the underlying data and computer code conveniently available, scientists could open a new era of innovation and growth. In October, the White House released a memorandum titled “Accelerating Technology Transfer and Commercialization of Federal Research in Support of High-Growth Businesses,” which outlines ways for federal funding agencies to improve the rate of technology transfer from government-financed laboratories to the private business sector.

I’m not a fan of this proposal.

The problem is, as I previously discussed, that the data and analysis techniques have value. They represent an investment in time a lab has made, and forcing that information to be given away means that any other lab can catch up in research, extract information from the data or apply the analysis tools to other data, all without a similar amount of investment.

The lab that did the work should get the credit for discovery, not only for the recognition and prestige but also to help in their competition for funding. Without overhauling the funding system, this proposal would be asking labs to handicap themselves in their quest for future funding.

Technology transfer is not that same thing as forced sharing of data and analysis tools, so I’m not sure what connection the authors were trying to make. The technology transfer they mention is from federal agencies to the private sector — this would apply to me, for example, if I helped discover or build something but our lab was not in a position to exploit the work, e.g. commercial development of a product, which is something that’s not part of our mission. But the government gets something back from that — it’s not just us giving it away to a business.

Flight Artists

High-Speed Animal Flight Videos Show Hidden Aerial World

With good lighting and a little luck, amateur videographers can use inexpensive digital cameras to transform blurred flight into breathtaking glimpses of animal behavior.

In that spirit, a Dutch program called Vilegkunstenaars, or Flight Artists, sent high-speed video tools to amateurs around the world. The challenge: Capture nature in flight.

Over the course of a year, the contest drew 460 amateurs who uploaded more than 2,400 slow-motion video clips shot with their complimentary cameras.

I’m a tad envious of them. The prospect of having a professional-grade camera … (cue Homeresque power-drool)

Taking a Non-Leap of Faith?

Time running out for ‘leap second’ that has kept us in step with our slowing planet

[T]hat [next] change could be the last of its kind for the leap second and for our fiddling with time. Telecommunications organisations and financial groups say the continual adding of leap seconds to computers increases the chances of errors being made. Precisely timed money transactions could go astray or vehicles could be sent tens of metres out of position if they are a second out in their measurement of time. Hence the bid to ban the leap second.

But there’s this – a nit at which I must pick

“However, these new, highly accurate atomic clocks also revealed that the Earth’s rotation is slowing down because of movements within the core of the Earth.

“The rate of change is not constant, however; it fluctuates over the years. Indeed, sometimes it does not slow down at all.”

Any change in mass distribution will contribute to a change in rotation rate because angular momentum will be conserved, but a really big term in all of this is the tidal braking from our interaction with the moon. The other contributions add noise to this, which is why the rotation speed can level off or even increase temporarily.

But since moment of inertia depends on R^2, changes in the core must involve a lot more mass relative to changes on the surface of the earth (from weather patterns and water location, for example) to contribute.

 

I had linked to an article about the problems with leap seconds some months ago, and the author came and gave a talk at the Observatory this past fall. Hearing details of some of the potential problems was interesting — the issue is that programmers generally don’t think about leap seconds, so how a system will respond is dicey, and as more and more systems rely on automation the odds of a dangerous failure increases.

There are systems that simply shut down at leap-second insertion time rather than deal with the unknown response of the computer code. But leap seconds are inserted at midnight UTC. Most of Europe is partying, without much business going on, or planes in the air. But it’s 4 PM in California, and in the morning in Asia. There’s potential for some serious complications.

The bottom line is that most people don’t care about leap seconds. Dropping them will impact astronomers, and mildly offend our sensibilities when noon on the solstices does not have the sun line up overhead — assuming you are at a longitude where this currently happens. But that’s just it: most of us aren’t. We accept time zones as a compromise between precise astronomical time and coordination and scheduling of our lives. It won’t surprise me if leap seconds are deemed more trouble than they are worth.

The Scientists' Dilemma

I recently had an interesting discussion with someone who is interested in science, but without training or experience as a scientist. The question was, basically: Why don’t we (scientists) all just lie to each other? i.e. what compels scientists to truthfully share their research results? It’s a fair question — we’re human and competitive to some degree, and at first blush there would seem to be a lot to gain from keeping competitors off-balance by feeding them false clues.

I will draw a distinction here between non-cooperation, i.e. secrecy, and deception. Certainly there are endeavors where information sharing is limited — corporate and military research have their secrets, and I suppose that some endeavors might actually try and mislead the competition. This secrecy is (in my experience) rare in the more open environment of academia. Why is this? There a couple of factors.

Science is big — really big — and there is a built-in symbiosis that has arisen. Nobody can possibly study every area of science, so we have to be able to trust that information we get elsewhere is valid. The so-called scientific method has developed ways to do this — we like to confirm experimental results either by replicating the work, doing a similar experiment or doing a more advanced experiment that uses the results, which gives a trust-but-verify attitude, and knowing that results are going to be checked is a motivation to be truthful. Reputations are at stake, and even if there were no peer review you wouldn’t want to be know as an untrustworthy researcher — if you are consistently wrong, whether by sloppiness or deceit, nobody will pay attention to you. So part of the answer is peer pressure.

Science is big in terms of career length as well — decades, vs the time scale of experiments, or more importantly, publications and talks, which is measure in months to a few years. If a scientist is going to engage in deception in order to complete an experiment first, the benefit has to last beyond that one experiment. And it doesn’t. Some level of cooperation serves any scientist’s interests much more than subterfuge.

In science, information is a valuable commodity. You publish and present results at conferences with the expectation that everyone else will do the same, and beyond this, you have discussions in the hallways or at meals, in which you discuss details that never make it into the papers or talks. Just reading a paper does not give you all of the information necessary to complete it — one might describe a certain layout for an experiment, but what isn’t discussed is how to get the experiment to work. The nice graph of data that has been published, for example, is the end result. There is no information about what knobs you have to tweak to get from an ugly, noisy signal to the nice one, and there is usually no discussion of the false paths one went down in pursuing the result. That’s what you talk about when you are trading information, and the value is that it’s a huge time-saver. It’s one justification for the graduate school system, where acquiring experience is given some value (overvalued, perhaps, by those paying salaries). Knowing what not to do is a benefit in terms of both time and money.

Bucking the system, then, threatens to cut you off from that flow of information. Someone more familiar math could no doubt go into details, but I’m sure that it’s some application of game theory. While you might be smarter than everyone else, you are not smarter than everyone else put together — even if you started with a lead isolation will eventually leave you far behind the pack as you have to try all of the dead ends, while the cooperative ones will share that information and save time. Taking the middle ground of simply not sharing is no better. People will stop talking to you once they realize that the relationship is asymmetric.

Since I work for the military, I run into the conflict between sharing and keeping secrets, which is pretty much divided along the lines of scientists vs military staff. You have to make your case that not sharing has a price — this information flow asymmetry would quickly shut one off from juicy details, and cost your program time and money to get the desired results. That usually works.

There’s another consequence of the value of information sharing, and I think it contributes to the scientific community’s attitude toward fraud. There are some self-policing communities that seem to have an “I have your back if you have mine” attitude and so misdeeds are sometimes not punished severely. But in science, fraud is a death knell. Part of this is because one of the parties to research can’t be convinced to go along: nature itself. If I falsify data, there will come a time when this impacts someone else, and I don’t have any control over the results of someone else’s experiment. And because, as I said, human nature might tempt us, the punishment has to be severe, such as revoking your degree.