RIP Edward Lorenz

Edward Lorenz, meteorologist and founder of chaos theory, passed away today at the age of 90. He discovered the chaotic properties of nonlinear systems as a result of an unexpected result while running numerical weather simulations in 1961, and changed the way we think about complex systems.

For those of you with a mathematical background, I recommend taking a look at his 1963 paper “Deterministic Nonperiodic Flow,” in which he proves one of the most basic results of chaotic dynamics (that nonperiodic flows are unstable against small perturbations), applies it to a simple problem in fluid dynamics, demonstrates vividly and in pictures the way that the system becomes unpredictable, and reflects on its significance for weather prediction. It seems a fitting way to mark his passing, and the paper is great; very straightforward1 and well-written, and full of the best pictures that 1963-era computing could produce.

1 By comparison to most technical papers in mathematics, that is, and especially to most papers on differential equations. I realize that this is not the best definition of “straightforward.”

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Published in: on April 17, 2008 at 12:25  Comments (12)  
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The latest “theory of everything…”

Several people have been posting, here and more broadly, about Garrett Lisi’s new candidate unified theory of fields and gravity. (Even slashdot seems to have picked it up) This got encouraged by Lee Smolin, of loop quantum gravity fame, getting publicly excited about it, and it makes for great news because Lisi isn’t currently a practicing physicist — he’s currently a surf bum with a PhD. The biggest problem is that this paper is wrong in some rather key ways.

Really technical digression, of interest only to physicists

Published in: on November 15, 2007 at 22:48  Comments (11)  
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Go Northwest, young man!

The latest round of news about polar ice melting being a lot faster than any models have expected — new satellite data from the ESA. What’s exciting about this one is that they show that the Northwest Passage, a fabled sea route from Europe to Asia via the northern coast of Canada that would shortcut both the Panama Canal and the much longer Cape Route, which explorers searched for in vain from the 15th century to the 20th, is for the first time in recorded history navigable by sea traffic from one end to the other.

Let the gold rush begin.

Published in: on September 15, 2007 at 19:04  Comments (6)  
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Buying votes or time

Very interesting op-ed piece by Shankar Vedantam in the Washington Post today about the effect of “campaign contributions.” He argues that the main impact of these contributions on elected officials isn’t to get them to change their mind about issues (which is why groups rarely contribute to politicians on the opposite side of the aisle from them) but rather to change their prioritization. He gives an interesting example, recounted by a former aide to Sen. Daschle about how they were working on a hunger relief bill when a drought started in South Dakota, and they context-switched to work on a relief bill for dairy farmers. According to this aide,

Daschle did not stop caring about hunger because he was working on dairy issues. And he did not start working on dairy issues merely because of campaign contributions. He genuinely cared about dairy issues, too. Money that people in the dairy industry spent on campaign contributions and lobbying did not have to buy Daschle’s views — he was in their corner to begin with. But what campaign contributions and the subsidization of legislative work that lobbyists provide do obtain is a subtle alteration in politicians’ priorities

The article further backs this assertion by noting that the distribution of funds by groups favors politicians who already favor them, not politicians who are on the fence or on the other side.

The conclusions that derive from this are interesting: it means that you shouldn’t care too much about who’s funding politicians you don’t like (except insofar as you can use that to make political hay), but you should be very alert to see which other groups are funding the ones you do like; they’re the ones competing with you for actual slices of the politician’s efforts.

Published in: on July 16, 2007 at 13:25  Comments (10)  
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Two Important Pieces

There are two things on the internet which are very worth your time at the moment.

The first one has to do with US politics. I’ll simply refer you to this post by Brad Hicks, since he wrote an excellent summary of what’s really important. It has to do with James Comey’s testimony to Congress a few days ago. The short version is that, when John Ashcroft was AG and critically ill, Alberto Gonzales (then the top White House lawyer) and Andrew Card (Bush’s Chief of Staff) went in to the hospital to try to force Ashcroft, while under sedation, to re-authorize mass wiretapping, even though he had concluded (while conscious) that it was illegal. Comey was acting AG while Ashcroft was sick, and rushed to the scene to try to stop them. He succeeded, the program was declared illegal, and the next day Bush ordered it to continue anyway, despite the formal advice of the Department of Justice. Comey’s testimony is stunning, and you should at least read the transcript — but if you have 20 minutes, it’s worth watching the video and seeing for yourself. If this is not cause to open an impeachment hearing — the deliberate and knowing violation of laws, the doing of such an action to attempt to expand police powers in direct and specific contravention to a law (FISA) designed to prevent that, and even the simple human action of browbeating a man under sedation to abet them in so doing — then nothing is.

(Edit: The most moving section of the testimony may be the earlier part, where Comey talks about the night meeting in the hostpital. But the key statement happens at [end of tape minus 4:31])

The second one is a bit lighter, but really great: The 26 Most Common Climate Myths. From the New Scientist, a detailed discussion of the 26 most common misconceptions about climate change, together with explanations, figures, graphs, and references to the original papers. This is a great bit of science journalism.

If you have any free time today, and are at all interested in either the political future of the US or in climate change, these are good things to look at.

Published in: on May 17, 2007 at 11:25  Comments (10)  
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The ice models are wrong.

Polar ice retreating much faster than climate models predict.

Something I’ve been saying for a while: The ice modeling in the current gold-standard models (like GISS-E) is Just Plain Wrong: it doesn’t adequately account for positive feedback in ice-melting, such as the way meltwater changes the ambient environment for ice, or the way that ice melt affects ambient atmospheric properties. A calculation like that is pretty much guaranteed to predict that ice melts only very slowly and adiabatically, instead of quickly and with marked “tipping points”.

Conclusion: We’re going to have a seasonally navigable North Polar Sea a lot sooner than many people anticipate.

Published in: on April 30, 2007 at 13:12  Comments (18)  
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Well, that’s reassuring.

I open up the news quickly, just to see if something interesting is up in the world, and what do I see?

Chimpanzees living in the West African savannah have been observed fashioning deadly spears from sticks and using the hand-crafted tools to hunt small mammals — the first routine production of deadly weapons ever observed in animals other than humans.

Which is pretty damned interesting from an anthropology (and primatology) perspective, although not the most cheering thing to read.

Published in: on February 22, 2007 at 16:06  Comments (8)  
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News day!

Hi everyone, lots of significant news stories today. Top of the line: the new Int’l Panel on Climate Change report is out. Or at least, the Summary for Policymakers; their web site is such an utter mess that I can’t find the actual report anywhere. Haven’t read it yet, will post once I do. (Maybe to ) Here’s pretty good news coverage from NYT. However, this report needs to be taken with a very serious grain of salt: Apparently they caved to political pressure and seriously damped the prediction about sea level rise, to basically assume that nothing bad ever happens to an ice sheet ever again. This is unfortunately total nonsense since ice sheets have been collapsing all over the place, and so it means that a lot of the predictions in this document are probably very off — in the conservative direction.

Next story, more fighting between Hamas and Fatah. Palestinians fall deeper into civil unrest. Subtext of this: After Arafat died, there was no central strongman. Hamas has been thoroughly infiltrated by Iranian agents and is working on its own little agenda, which is part of why it started shelling Israel a while ago and kidnapping soldiers (they did it before Hezbollah, when the latest Lebanese war started! These groups work in sync now) without bothering to ask the Palestinians if that was a good idea. And Fatah, Yassir Arafat’s old party, specializes mostly in corruption, despite what appear to be good intentions by its current leader Mahmoud Abbas. Fatah has the presidency and Hamas the parliament, and both have their own armed forces. So the two factions of Palestinian government are busily killing each other. If it weren’t for the fact that this is wholly destructive of any remaining bits of functioning civil society and infrastructure in the Palestinian territories, and thus one of the few ways left to make life systematically worse for the average Palestinian, I would say that these batch of idiots shooting one another is the best thing they could do with their time.

And yet another report on Iraq indicating that the place is a mess and deteriorating rapidly. (Shocking!) On the same day, a suicide attack in southern Iraq killed 60 and wounded 150.

OK, for anyone who hasn’t figured this out yet, something important to understand. Majority rule is not the defining feature of democracy; there have been plenty of dictatorships that had the support of the majority. The key feature is protection of the rights of the minority. This is the center of the “deal” in democracy: when group X loses an election, they relinquish power, because they trust that the group taking power will not use that power to, say, brutally kill group X, or take everything X owns, or change the laws so that X is never again allowed to be in power. Without that level of trust, any election is simply a sham. In Iraq, there has never been this basic level of trust, because the basic level of political alliance is to tribe (and sect, and so on). A Sunni would have to be out of his mind to vote for a Shi’ite candidate, or even to let a Shi’ite candidate take power, because they know that the Shi’ites would have no compunction at all about killing them if they had the instruments of power, and vice-versa. In a situation like this, hopping for democracy is utterly ridiculous; civil war is the only possibility, ended either by one group seizing power forcibly over the others or by stable partition.

Please, please, please, don’t forget that. Having elections does not make you a democracy any more than going to a garage makes you a car.

OK, back to work for me.

(PS: Sorry, I’m just linking to the NYT stories today; these are being covered everywhere, check your favorite news outlet for details. Except for the climate report, which I couldn’t find anywhere at all on Fox News’ web site; what a shock)

Published in: on February 2, 2007 at 11:54  Comments (32)  
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Random tidbits

Newsweek and the Washington Post are hosting a dialogue on the subject of faith and the possibility of coexistence between religions. Contributors so far include the Dalai Lama and Mohammad Khatami. Interesting to hear them speak, and to see people’s responses.

There has been significant progress towards sequencing Neanderthal DNA, and there are hopes of having an almost complete sequence in a year or so. This opens all kinds of doors to looking at what, genetically, makes us human.

On a related note, Slate is running an article about cross-species mating, and in particular why humans could or could not breed with other species. (This was prompted by a recent paper suggesting that humans and Neanderthals may have mated, and that’s the origin of some of our modern cranial capacity genes)

Back in the land of geopolitics, a Chinese sub managed to sneak up on a US carrier group. Apart from ‘s comment that someone O4+ is going to be in seriously deep shit over this, this suggests that they’ve been doing quite well on the technology needed to make highly silent motors and so on. (Whether they did so on their own or “acquired” this technology from elsewhere is an interesting question. China’s military has certainly never suffered from not-invented-here syndrome.)

There’s really a lot having to do with China going on right now. China and Iran are cementing an alliance, with Iranian oil getting ready to flow east. (Question: Anyone have some info as to what the routes are going to be? It looks like every possible path is going to involve some combination of Pakistan, Afghanistan, Tajikistan, Turkmenistan, Uzbekistan, and Kazakhstan, which could make for some very exciting places to put oil pipelines. Don’t forget what happened to Russia’s Caspian -> Turkey pipeline, that once upon a time went through Chechnya…) Iran may well have had observers at N Korea’s nuclear test. (Unconfirmed rumors, but wouldn’t be all that surprising if true; those countries have been working hand-in-hand on this for a while.) China is similarly making alliances with a lot of other dubious places that have useful resources, like the Sudan and Zimbabwe, but that the West by and large wants nothing to do with. This certainly makes the notion of sanctions as a weapon pretty much infeasible, since that depends on some sort of unity, and could bring us back towards a bipolar world — if, that is, China’s “burn through the environment as fast as needed to get economic progress” algorithm doesn’t hit a really nasty obstacle in the near future. Which is not something that I would bet against. (Side note: They’re burning through this a lot faster than the US or Europe ever did, because they have a much higher population, and they have old systems in place which turn into a huge social unrest risk if they don’t keep the economy flowing. Add to this an almost total willingness to sacrifice the countryside to protect the cities, again because of unrest risk, and there’s a real problem brewing in China. Not that this would be useful to the furthering of US interests or anything.)

Really, China is in an interesting fix. They got where they are today by being the cheapest producer of all sorts of things. Now other Asian countries, especially in SE Asia, are thinking about competing with them; so what will China do? Keep trying to undercut them, or move into higher-end markets? The latter is more sustainable in general, but it doesn’t necessarily scale to a huge population quite as smoothly, and China has been moving so fast that it hasn’t really had time to transfer the benefits from its previous wave of growth to the population as a whole, so the moderating factor that that would create isn’t available. And trouble from the countryside, local riots, complete collapses of regions due to ecosystem failure, and so on, keep happening more and more often, while people keep streaming into already-overloaded cities. It reminds me a bit of the USSR: it looks awfully menacing on the outside, but if you look at their underlying logistics and infrastructure, there’s a very different thing going on.

Dammit, I’m not nearly enough of a China expert. Perhaps I’m going to need to start on that.

Published in: on November 15, 2006 at 16:10  Comments (2)  
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Money and climate change

For once, have some good news. It looks like Katrina was a wake-up call for one group that realized it had a lot to lose from climate change: the insurance industry. And because insurance companies are very big, they have direct influence over the polluters at the same time that they’re exposed to risk from the polluters screwing up. (If they were smaller and more specialized, that wouldn’t be the case — an insurer just of power plants wouldn’t be nearly as worried about flood risks as a general insurer) So apparently, they’re starting to do things about it.

I see this as really promising: It’s a case where being very big gives a company a much broader perspective on consequences. (It reminds me of some recent articles comparing HMO’s to the VA. Since the VA is stuck with people for their whole lives, in essence, it makes them think a lot more about preventive care, general quality-of-life, and so on, rather than on short-term solutions whose long-term costs they can remove by dumping patients. Sometimes, a company being big can be a very good thing for the world.)

Published in: on October 12, 2006 at 17:10  Comments (8)  
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