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They all look the same, said Trent Lott

from CNN via Crooks & Liars:

Lott went on to say he has difficulty understanding the motivations behind the violence in Iraq.

“It’s hard for Americans, all of us, including me, to understand what’s wrong with these people,” he said. “Why do they kill people of other religions because of religion? Why do they hate the Israeli’s and despise their right to exist? Why do they hate each other? Why do Sunnis kill Shiites? How do they tell the difference? They all look the same to me.”

You know, for once I think I know how the Trent feels. I have the same problem. Not so much with the groups he mentions. Being bombed and then being told to like it tends to make people mad. They’re weird that way.

 

Trent Lott

redneck with Bush poster

But when it comes to these people, man, do I know how he feels. Their violence is so senseless. Why do they hate everyone who’s different? Is that why they all look the same to me?

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The Relativity (and Infinite Improbability?) Drive

It’s here, it’s queer, get used to it. Really it is. Stanley Shawyer, a senior aerospace engineer in England, has built a working prototype, and it is beyond queer. It’s downright magic. He’s calling it a staid-sounding “electromagnetic drive,” or emdrive, but he could have called it the Infinite Improbability Drive. (Hat tip: Douglas Adams, of course).

As far as I can tell, this has not appeared in a peer-reviewed journal (Physical Review Letters, are you asleep at the switch?) so maybe it is a load of bollocks as one scientist quoted in the article below says, but on the other hand, a number of other scientists say it’s brilliant. Time will tell.

The emdrive is based on the force exerted by light when it hits a surface, which is the same force used by solar sails. The difference is that it uses waveguides to channel and amplify the pressure of light. (Waveguides are like fiberoptic strands in one of those novelty table lamps, except that the ends in this case do not allow the light to escape.) The waveguides are shaped so that the photons exert more pressure at one end than they do at the other. Whenever there’s a difference in energy levels, it can be used to do something, whether it’s to push a space craft or to heat a pot of water. But the light is bouncing around inside the sealed waveguide, so how does that exert any pressure outside the “light pipe”?

This is where the magic comes in. Because the photons are travelling at the speed of light, the forces they generate have to be understood in terms of Einstein’s special theory of relativity. And that says things moving at light speed are in their own frame of reference. They’re in their own universe, so to speak, and the asymmetrical force inside the cavity exerts a push as if it was outside of it.

No, I don’t understand it either. But then, I don’t understand gravity, and that doesn’t stop it from exerting force.

Excerpts from the article in New Scientist by Justin Mullins, Sept. 8, 2006. (via Slashdot.)

Take a standard copper waveguide and close off both ends. Now create microwaves using a magnetron, a device found in every microwave oven. If you inject these microwaves into the cavity, the microwaves will bounce from one end of the cavity to the other. According to the principles outlined by Maxwell, this will produce a tiny force on the end walls. Now carefully match the size of the cavity to the wavelength of the microwaves and you create a chamber in which the microwaves resonate, allowing it to store large amounts of energy.

What’s crucial here is the Q-value of the cavity – a measure of how well a vibrating system prevents its energy dissipating into heat, or how slowly the oscillations are damped down. For example, a pendulum swinging in air would have a high Q, while a pendulum immersed in oil would have a low one. If microwaves leak out of the cavity, the Q will be low. A cavity with a high Q-value can store large amounts of microwave energy with few losses, and this means the radiation will exert relatively large forces on the ends of the cavity. You might think the forces on the end walls will cancel each other out, but Shawyer worked out that with a suitably shaped resonant cavity, wider at one end than the other, the radiation pressure exerted by the microwaves at the wide end would be higher than at the narrow one.

… The result is a net force that pushes the cavity in one direction.

And the device seems to work: by mounting it on a sensitive balance, he has shown that it generates about 16 millinewtons of thrust, using 1 kilowatt of electrical power. Shawyer calculated that his first prototype had a Q of 5900. With his second thruster, he managed to raise the Q to 50,000 allowing it to generate a force of about 300 millinewtons – 100 times what Cosmos 1 could achieve. It’s not enough for Earth-based use, but it’s revolutionary for spacecraft.

Shawyer is looking ahead to the next stage of his project. He wants to make the thrusters so powerful that they could make combustion engines obsolete, and that means addressing the big problem with conventional microwave cavities – the amount of energy they leak. The biggest losses come from currents induced in the metal walls by the microwaves, which generate heat when they encounter electrical resistance. This uses up energy stored in the cavity, reduces the Q, and the thrust generated by the engine drops.

Fortunately particle accelerators use microwave cavities too, so physicists have done a lot of work on reducing Q losses inside them. The key, says Shawyer, is to make the cavity superconducting. Without electrical resistance, currents in the cavity walls will not generate heat. Engineers in Germany working on the next generation of particle accelerators have achieved a Q of several billion using superconducting cavities. If Shawyer can match that performance, he calculates that the thrust from a microwave engine could be as high as 30,000 newtons per kilowatt – enough to lift a large car.

This raises another question. Why haven’t physicists stumbled across the effect before? They have, says Shawyer, and they design their cavities to counter it. The forces inside the latest accelerator cavities are so large that they stretch the chambers like plasticine. To counteract this, engineers use piezoelectric actuators to squeeze the cavities back into shape. “I doubt they’ve ever thought of turning the force to other uses,” he says. [This reminds me of the (apocryphal) story about Robert Boyle and his buddies in the 1600s who realized that the steam pushing up a pot lid could be used to push anything.]

Then there is the issue of acceleration. Shawyer has calculated that as soon as the thruster starts to move, it will use up energy stored in the cavity, draining energy faster than it can be replaced. So while the thrust of a motionless emdrive is high, the faster the engine moves, the more the thrust falls. Shawyer now reckons the emdrive will be better suited to powering vehicles that hover rather than accelerate rapidly. A fan or turbine attached to the back of the vehicle could then be used to move it forward without friction. He hopes to demonstrate his first superconducting thruster within two years.

Be great if it worked out on schedule, but I’m willing to wait three, even four years for my levitating car.

Technorati tags: relativity drive, electromagnetic drive, emdrive, Shawyer, science, energy, , space

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The Pope, the Jihad, and the Sword

What is it about popes? With rare exceptions, like John XXIII, what a bunch of benighted enablers of balderdash. Maybe it has to do with the selection process being limited to a few old men in skirts.

Now the current one has managed to quote a fourteenth century emperor as if he had some relevance six hundred years later. (Quoted from the BBC)

…[H]e [the emperor] addresses his interlocutor with a startling brusqueness on the central question about the relationship between religion and violence in general, saying: “Show me just what Muhammad brought that was new, and there you will find things only evil and inhuman, such as his command to spread by the sword the faith he preached.”

That from the head of a religion that gave people the Inquisition and witch-burning. That from the head of a religion that was so famous for converting people by fire and sword that it’s a joke in one of the world’s most indispensable books, 1066 and All That.

The sad thing is, old Ratzinger–sorry, Benedict XVI–was actually trying to make a good point. Violence has no place in religion, which is sort of like saying that moms and apple pie go together. You’ll get no argument from anyone, except of course the people trying to use religion as an excuse for their own greed or hatred. That, too, is not limited to Islam or Christianity. You could probably dig up a paleolithic shaman with ten followers, and find a couple grunting slogans to justify killing their neighbors.

Ratzinger-Benedict was also trying to say that narrow Western concepts of reason interfere with dialogue with non-Western cultures. An attitude of “The facts, ma’am, just give me the facts” is indeed too limited to encompass any of the finer things in life. The Westerners have a lot to learn. So does everyone else. Worshipping gods made in our own image is not working out for us.

John Lennon said it best:

Imagine there’s no Heaven
It’s easy if you try
No hell below us
Above us only sky
Imagine all the people
Living for today

Imagine there’s no countries
It isn’t hard to do
Nothing to kill or die for
And no religion too
Imagine all the people
Living life in peace

Technorati tags: Pope, Islam, Christianity, terrorism, violence, religion

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Human Rights Are Not Optional

I know I’ve said it before. I know I’m repeating myself. I still can’t believe it needs saying at all.

You can’t trade human rights for expedience. It does not work. It’s not only bad, as in BAD, but it achieves less than nothing. Let me run through a couple of obvious examples. (After all, if their message hasn’t gotten across yet, they must bear repeating.)

Slavery. In recent times, it created–and still creates–suffering among blacks. No particularly startling insight there. It held back the economic development of the US South for over a hundred years, and the area still hasn’t caught up. It created whole swathes of whites who have to believe in fear and hatred to justify what was and is done. It led to a disastrous war that would never have happened if slavery had been outlawed from the birth of the republic. It wasn’t outlawed then because the rights of a bunch of blacks wasn’t worth the trouble of arguing with a bunch of much richer whites.

Anti-semitism. This one is overused to the point of coma, so why haven’t we learned the lessons yet? Before the Second World War ground in its awful message, some anti-semitism was quite acceptable. It’s been lost in the fog of embarrassment just how normal it was to ignore Russian pogroms or to subscribe to conspiracy theories about world domination by a cabal of Jewish bankers. But even so, Kristallnacht, the night of November 9, 1938 that was a lynch party to end all lynch parties, should have been an alarm loud enough to wake the morally dead. However, at the time the rights of a bunch of Jews wasn’t worth the trouble of taking on a military superpower. It didn’t save anyone from having to deal with the Nazis eventually, of course. It just made it a lot more costly.

Moving right along to what caused me to go on this rant, the following is a quote from one of the best, most insightful, and most intelligent left wing bloggers:

Like most extreme reactionary movements, Al Qaeda has no meaningful economic or political program …. But what it does have going for it are wide and deep fears of cultural penetration and Western domination …. These are precisely the fears the administration and the neocons appear determined to stoke with their sweeping demands for “democratic” but slavishly pro-American regimes, privatization, women’s rights, Western-style individualism, etc.

This is like those lists on an SAT: “Find the element that does not belong. Red. Green. Blue. Purple. Concrete.” Putting “women’s rights” in amongst privatization and puppet regimes sets at nothing the unbelievable courage of people who try to give an education to girls in Afghanistan, or who try to help the victims of sexual crimes in countries where blaming the victim is taken for granted. It sets at nothing the superhuman efforts of the Shirin Ebadi’s of the world who are using every ounce of their strength to get at least some of the most basic human rights for the female half of the population in their countries. By implying that we should deny truth to avoid offending tyrants–we who would lose nothing but some money if we did–he sets at nothing the sacrifices of life, limb, sanity, and family that every fighter for human rights risks under those tyrants.

But human rights are a luxury, right? People who aren’t even really men can’t be worth an argument with a bunch of guys with their heads up their seventh centuries. Think about it. These guys have both oil AND guns. It’ll be different this time. It’ll really be much easier, much cheaper, much less painful if we don’t let the rights of these minor groups interfere with the big picture. It’s never worked before, and right now it’s making us more dependent on oil, more involved in wars, and it’s breeding more drug-resistant epidemics in more failed states. But if we just ignore people’s rights harder than ever, this time it will work.

Right?

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Facts and the danger from GM food

Evidence of harm from genetically modified (GM) food is one of the under-reported issues discussed by the generally excellent Project Censored for 2006. Specifically, they report on studies of rats and mice fed “GM soy” and that the rats died young, were underweight, and/or had other anomalies. There are several things that are missing in almost all the non-technical reporting on GM food (and plenty of things missing from the scientific reports, too).

First, they don’t specify what kind of genetic modification took place. (PC at least does say “Mon863,” but that doesn’t tell us much.) The beans could have been modified with jellyfish genes to make them glow green in the dark. They could have been modified with a vitamin A-producing gene (as some rice actually is). However, they probably weren’t. The majority of GM-ing (about 75%, if I remember right) is done by Monsanto to introduce RoundUp weedkiller resistance into crop plants. Given the “Mon” prefix, that’s probably what these studies were about.

A bit of background is needed here. RoundUp (which, interestingly enough, is made by Monsanto) kills weeds by interfering with their growth hormones. Plants have very different hormones from animals, including humans, and so destroying those hormones shouldn’t have any effect on animals. The problem is that life is infinitely complex, there are vast amounts we don’t know about biomolecular interactions, and chance matches that cause curious downstream consequences are not unheard of. Cannabis, for instance, has an effect on the human brain because a plant molecule (whose probable function is repelling insects) can interact with nerve receptors whose normal target is very different molecules produced by humans.

So, did the rats do poorly because the GM soy had weird stuff in it that was harming them? Or did they do poorly because it just wasn’t very good soy?

Assuming the GM-ing did involve RoundUp resistance, that last question is not rhetorical. The point to the resistance is to allow frequent spraying with the weedkiller without killing the crop itself. (Yes, Monsanto has farmers paying for patented seeds so that they can pay for more Monsanto weedkiller to pour on them.) RoundUp resistant crops are generally also grown with plenty of insecticide spraying and chemical fertilizer, and that kind of produce has fewer vitamins and minerals. That’s a matter of observable fact, but it’s not necessarily anything directly to do with the genetic modification itself. The GM-ing just allows the crop to be produced under even more hostile conditions than ordinary chemical farming.

If the GM soy killed the rats by being the equivalent of a lifetime of soda pop and french fries, then that’s very interesting, but not actually panic-inducing. If it killed them as a direct consequence of the molecules produced by RoundUp resistance, then there really needs to be a red alert. An Australian CSIRO study found an immune response to GM peas (gene unspecified), and that suggests a possible direct molecular interaction. It really, really, really needs follow-up studies immediately. (PC cites this as a “private research institute,” but CSIRO is “the Commonwealth Scientific and Industrial Research Organisation, … Australia’s national science agency and one of the largest and most diverse research agencies in the world.” (From their website.))

The question of why the rats did poorly is absolutely critical, but the point is hardly ever raised in non-technical articles.

Another question I don’t see addressed is not technical in itself, but does require awareness that there are different genetic modifications. Critics of GM food would like to see it banned. Proponents say we have to move with the times or people will starve. Both are being silly. Vitamin A-enriched rice is a Good Thing. Disease resistant crops that require less herbicide or pesticide are also (usually) good. (But consider the impact on Monarch butterflies due to the deaths of caterpillars caused by caterpillar-killing genes added to corn in the US Midwest.) And as for people starving, they aren’t doing it due to a lack of food, even without GM-induced abundance. People are starving because of wars or because staple foods are too expensive. Genetic modification (unless it prevents human greed and stupidity) will do nothing about that.

On the other hand, banning GM food that has no socially redeeming features seems like a good idea. Pouring out more RoundUp is good only for Monsanto. It’s terrible for everyone else. Let us, by all means, ban that.

The point I’m trying to make is that the opposition to GM food needs to be done intelligently. It needs to be based on fact. And a first step in that direction would be for non-technical talk on the subject to tell us what those facts actually are.

Technorati tags: , photovoltaics, frankenfood, genetically modified food, genetic engineering, RoundUp, Monsanto

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Katrina photos by Alan Chin

via BAGnewsNotes (which I found in Crooks and Liars).

A woman from New Orleans said, “I hate this stupid anniversary.” Me too. As a realist (see blog title…), I need reminders that people are NOT venal idiots. Then I came across Alan Chin’s photos, which I’d never seen before. (I live under a rock.) They say it all. Go look.

One example, showing the proudest flag I’ve ever seen:

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