Sunday, March 31, 2013

Puzzles

With a hat tip to Texan99, a fascinating report on the dynamics of breast milk. There are indications that when a mother senses that the infant is suffering from infection, she automatically ups the immune factors in the milk. Or maybe both are suffering and the reaction is hers? They say they can't prove it yet.
In humans, there’s early data suggesting that mothers produce fattier milk for boys than girls. But that may be only part of the story, as Hinde has found with rhesus macaques. "Just because sons are getting better milk doesn’t mean they’re getting more. It looks like they’re getting very similar total calories."

The macaque male babies get more cortisol than the females, and cortisol in infancy makes them more adventurous later in life.

And one of the sugars isn't digestible by babies--but by some of their gut bacteria. We all knew (I hope) that mother's milk was better than formula (though kids grow fine on formula), but I didn't expect individual tailoring like this.

But one thing: where do the babies pick up the gut bacteria? From the dirt? From mother's skin? They aren't present in utero, are they?

Lots of simple things turn out to be extremely complicated.

Like dirt, if the subject change isn't too jarring. There are so many different organisms in topsoil, communicating with each other directly or accidentally, so many chemicals at work--it is hard even to figure out which are inside the organisms and which outside. Last time I asked a researcher he said they were still scratching the surface. So to speak.

From the same aggregator Texan99 linked to (Rocket Science) is a link to a report on a study of the remains of "governors of ancient Egypt" which concludes that they were often malnourished and estimates only a 30-year average lifetime.

Unfortunately the home site is in Spain and not translated, so picking out critical details is hard. But I'm a little puzzled. It seems a bit counter-intuitive that the upper class would be seriously malnourished as a general rule (unless there were some fatuous diet fads afoot). Maybe the Nile was polluted, but IIRC they made plenty of beer. The team found a disproportionate number of 17-25 year-olds and I gather they drew conclusions from that. But if this was a cemetery for the governors and their families as claimed, perhaps only the folks who died on tour were buried there, and the rest returned to be buried in their ancestral region. They find Nubian bones there too, from which they infer intermarriage (or maybe they found obviously mixed ancestry bones too; I couldn't figure that out). (Years ago I was surprised to learn that pathologists had no trouble making accurate racial estimates from just bones.)

Wednesday, March 27, 2013

Extremophile genetic engineering

This story suggested they can make fuel from CO2. A little closer look a the article suggests that the editor had a bit of THC in his CO2. Executive summary: an extremophile microorganism that lives by ocean vents was modified to use CO2, provided you feed it some hydrogen. Potentially you could more readily synthesize various industrial chemicals that way; they got one of the big 12 so far.

The abstract isn't too jargon-laden (though I wonder why they say photosynthesis is inefficient), and makes an amusing comparison with "Discovery May Lead to the Creation of Biofuel from CO2 in the Atmosphere." Or you don't want to laugh you can cry. Photosynthesis makes the biofuels. This is a clever way of generating other chemicals. Kudos to Keller et al for thinking of using extremophiles.

Sunday, March 24, 2013

Parody

AVI found a song and the original it was a parody of and commented:
It was written as a parody of an American tune, My Nellie's Blue Eyes, which the songwriter found appallingly sweet, sentimental, and trivial. We can therefore suspect that the original would hang around here for decades after.

A song can certainly be incompetent--at some level all are; "the sad incompetence of human speech" never quite does justice to experiences like this:

But he never understood it as now, suddenly, he understood Rosamond's arm when she leant forward to pass a plate to her sister; somehow that arm always made him think of the Downs against the sky. There was a line, a curved beauty, a thing that spoke to both mind and heart; a thing that was there for ever. And Rosamond? Rosamond was like them, she was there for ever. It occurred to him that, if she was, then her occasional slowness when he was trying to explain something was there for ever. Well, after all, Rosamond was only human; she couldn't be absolutely perfect. And then as she stretched out her arm again he cried out that she was perfect, she was more than perfect; the movement of her arm was something frightfully important, and now it was gone. He had seen the verge of a great conclusion of mortal things and then it had vanished. Over that white curve he had looked into incredible space; abysses of intelligence lay beyond it. And in a moment all that lay beyond it was the bright kitchen, and Sir Bernard standing up to go into the other room.

or (same author)

bright as if mortal flesh had indeed become what all lovers know it to be. ... But no verse, not Stanhope's, not Shakespeare's, not Dante's, could rival the original, and this was the original, and the verse was but the best translation of a certain manner of its life.

The "sweet and sentimental" songs don't do it justice, but they at least express something that irony only does at one remove, when irony isn't mocking the experience completely. I wonder if the ironists never had that quick moment of surprise, or if it was tied to something that disappointed and they want to forget, or if they think only things they can repeat are real. They arrange another meal, or another romp in the hay, or another evening in the Grand Canyon, but not the moment of awe; so it must not have been quite real.


It occurs to me that because Mickey Mouse was copyrighted and not trademarked, American readers are not supposed to click on the links to that Australian site.


UPDATE: I should have been a little clearer with the title. I'm not deprecating parody as such: I've been generating parodies of one stripe or another as long as I can remember, and still automatically revamp lyrics. (The best I can do is a couple of lines before I have to stop and think a while, though.) (Maybe next Lent) And some parodies (Alice in Wonderland has quite a few) are so much better than the originals that they replace them.

What annoys me is the assumption that sweetness and sentimentality are appalling. Incomplete, yes. Worth mocking in themselves, no.

And yes, I have had a moment or three of the sort alluded to in the Williams quotations, but of course not exactly like them.

Friday, March 22, 2013

Extinctions in the news

Scientists trying to date the end-Triassic extinction (hat tip to SciTech) say they've used uranium in zircon crystals from the rocks to bracket "massive volcanic eruptions from a large region known as the Central Atlantic Magmatic Province (CAMP)" to be able to say that they happened over a relatively short time scale: 40,000 years. Over a long time, eruptions don't hurt much of anything (except locally), but dump vast amounts of sulfur dioxide in the air in a short amount of time and you can have problems.

Blackburn et al combined different approaches to try to estimate the dating: the Earth's wobble means that sedimentary rock accumulates with a pattern that has a cycle of about 26,000 years. They compared estimates taken from this with the classic U←Pb decay studies of zircon crystals, and came up with an error estimate of 30,000 years for dating the "CAMP" materials. They dated not the main flow, but "feeders" (suitably sandwiched rocks weren't available elsewhere) which are "interbedded with strikingly cyclical lacustrine strata," looking to "compare the time durations between basalt flows estimated by orbitally tuning the sedimentary rocks with differences between the zircon U-Pb dates of the flows.

OK, they found 4 lava flows, spaced at about at, 60, 290, and 650kyear after the extinction event. From their Figure 2 I only count 3; the first and second either don't overlap (their count) or are too close to call (my count). (No, I am not going to try to give you a better picture; I suspect this is pushing fair use pretty hard already.)

It isn't obvious exactly when the extinction event shows up. The definition they use is an aquatic one: when a particular ammonite shows up. Translating that to land-based measurements contributes largely to their 40 kyear uncertainty in comparing the extinction to their measures (not their fault; that's just the way things are in paleontology). But one thing seems pretty clear from their results: "the biologic recovery associated with the TJB was underway even as subsequent CAMP eruptions ... were occurring" later. (TJB=Triassic/Jurassic Boundary)

Pretty impressive chronological work.

I'm a little more suspicious of the dino-killer comet claims. They compare iridium and osmium levels and estimate that the impacter was smaller, and therefore must have been much faster than everyday asteroids--which leaves comets. Except why would comets be enriched in iridium? True, they might collect some from cosmic dust, but I thought they were mostly ices. (The comparisons I've seen so far comparing comet dust and cosmic dust isotope ratios have been for low atomic number. There is a body of literature on comet dust, plenty of puzzles remain for budding cosmicgeologists.)

On the other hand, one estimate for the ratio of volatiles (ice, CO, etc) to silicates etc is about 1:1. I'm not sure where they got the estimate, and am positive it would change with repeated sweeps near the Sun. So if the non-volatiles are half the mass, and those non-volatiles have the same elements concentrations as asteriods, then maybe it works OK after all.

It turned out to be a bit harder than I expected to find some simple numbers on concentrations. From here I read that iridium is O(50) parts per trillion except at the KT boundary where is is O(10) parts per billion (and that it could take 100,000 years for that much to precipitate out, meaning the boundary might be thicker than a thin layer--something I hadn't thought of). Here I read that some chondrite meteorites have iridium concentrations between 300 and 650 parts per billion.

Something about that ratio bothered me. Be generous and let the dino-killer have 1 part per million iridium. A world-wide layer of 10 parts per billion means that the dino-killer contributed 1% of the whole planet's stuff sifting into the future rocks for that era. That seems like kind of a lot. If the thing was an asteroid 10km across, then that's about 500 cubic km, and according to that font of all wisdom erosion is about 75 billion tons/year (they make that 13-40x normal), so about 3 cubic km/year would have been going to the sea back then (wave hands violently). So it actually could account for it if the iridium settled out over about 10,000 years. The numbers seem to be closer to ballpark than my naive impression of them.

And the good old Deccan Trap might have mixed in some extra iridium. I still think a broken asteroid/comet hammering the future Carribean and "popping a pimple" on the other side of the Earth is a satisfying resolution of the volcano/meteor disputes. But maybe Blackburn et al will try their hand at that next and prove the events were too far apart.

Drowning

I swim like a brick, and therefore am not the ideal person to rescue somebody, but maybe someone else would find an explanation of the symptoms of drowning useful. There are also a number of videos on drowning. A local middle schooler is in critical condition after nearly dying in the high school pool two days ago at the end of a class, with 3 life guards on duty.

Thursday, March 21, 2013

Maybe a different profession? Or maybe not.

Suppose you spent 30 years as missionary and found one convert. (And you weren't too happy with him) I hadn't known that about David Livingstone, who won only one man in his career as a medical missionary. Although that one man turned out to be a tremendously effective evangelist ...

To be fair, Livingstone wasn't working full-time at evangelism the whole time; he was also exploring. I wonder if he heard a little of what his disappointing protege accomplished; the simple online biographies don't seem to say.

Pressed on my attention...

The phrase "weak as a kitten" doesn't seem perfectly apt. They are small and light, but can cling quite tenaciously to a sweater. Pound for pound I think they're stronger than I, who can more or less balance on my hind legs but couldn't cling to anything to save my life.

And did you ever notice how much the lines in Deuteronomy "Cursed shalt thou be in thy coming in, and cursed shalt thou be in thy going out" and "In the morning you shall say, Would God it were even! and at even you shall say, Would God it were morning!" sound like the flu?

Saturday, March 16, 2013

Nixon again?

Nixon has several villainies in his record: the wage-price freeze and his effort to be an emperor: above the law and able to command that crimes be committed for his benefit. Now I hear claims that he sabotaged peace talks for campaign benefit, encouraging the South Vietnamese to back out of negotiations in Oct 1968.

The timetable seemed a little odd (Johnson declared a bombing halt 31-Oct-1968), so I tried to get some more details from sources that weren’t referencing the original news item. The linked article suggests a reason for his worrying about the Pentagon Papers: he wasn’t sure if there was some damning evidence associated with them. Unproven, but could be. But it is also evident that there was some fuzziness: Humphrey and Nixon were both making public statements that undercut the administration’s negotiating position. (And later on the US' fallback plans were published while negotiations were still going on—everybody was getting into the treason act, it seems. That doesn’t seem to go out of fashion: Newspapers and presidential candidates still do that sort of undercutting.)

Anyhow, between Humphrey spooking the South Vietnamese and Nixon encouraging them to back out, it complicated negotiations. Were the North Vietnamese serious? Would it have made any difference? They knew the war was unpopular and had every reason to jerk the US around a little more.

My first guess is that it didn’t make a lot of difference in the long run, but that Nixon was worse than he appeared.

Trying to focus on a constellation

Naviaux et al have a paper out on "Antipurinergic Therapy Corrects the Autism-Like Features in the Poly(IC) Mouse Model", so naturally I was interested. One of the key points is in the introduction, which I reproduce below.
The majority of children with ASD develop disease as the result of interactions between large sets of genes and environmental factors. Common comorbidities in non-single-gene forms of ASD provide important clues to shared mechanisms of disease. Comorbidities include epilepsy [2], GI abnormalities [3], sleep disturbances [2], abnormalities in tryptophan metabolism and platelet hyperserotonemia [4], altered intracellular calcium and mitochondrial dynamics [5], hypoimmunoglobulinemia [6], hyperuricosuria [7], methylation disturbances [8], disturbances in sulfur [9] and glutathione metabolism [10], neuroinflammation [11], cerebellar vermis hypoplasia [12], and Purkinje cell loss [13]. We hypothesized that all of these clinical comorbidities can result from a single, evolutionarily conserved, metabolic state associated with a cellular danger response (CDR). Since mitochondria are located at the hub of the wheel of metabolism and play a central role in non-infectious cellular stress [14], innate immunity [15], inflammasome activation [16], and the stereotyped antiviral response [17], we searched for a signaling system that was both traceable to mitochondria and critical for innate immunity. Purinergic signaling via extracellular nucleotides like ATP and ADP satisfied these requirements. In the following study we tested the role of purinergic signaling in the maternal immune activation mouse model of ASD and show that antipurinergic therapy reverses the abnormalities found in this model.

I left the footnote references in as an aid to counting. That’s quite a constellation of problems, and it would be fascinating, and quite a coup for the authors, if they revolved around a common mechanism.

Their results seemed to show some improvement, but a larger study would be more convincing. One the brighter side, the intervention was at 6 weeks, which is roughly (4-8 weeks) when mice become sexually mature, which suggests that even fairly late intervention might be fruitful. If it all works, of course. We won’t know if this has any bearing on humans for a long time, nor whether this sort of thing addresses the whole constellation.

Still, something to keep an eye on.

Trying to shape opinion or unable to comprehend?

On a CBS site I found the following internet poll:
Are you surprised it's actually illegal for 140,000
 unmarried Virginia couples to be living together?
  • Yes. How is that possible?
  • No. There are a lot of outdated laws.
  • If that's true, I'm breaking the law.

Vote

View Results

So I have a poll of my own to match it.

Was the poll composer

  1. completely ignorant that the law might have a reasonable purpose?
  2. trying to stir up opinion against it?
  3. trying to show how cool and with-it he is?

Thursday, March 14, 2013

Francis

Don't be just "a compassionate NGO".

I like it. He's probably seen NGO's up close and knows the qualifier isn't automatic. And without the living center to renew it, even compassion gets eroded away.

I gather the usual suspects are shocked that the pope turns out to be Catholic, and have been busily trying to dig up or innuendo-up as much dirt as they can. By their fruits you know them.

I'm not exactly the best person to be measuring somebody's holiness, but so far so good, and prayers and best wishes for Francis.

Correlation and causation and failure of imagination

The title is invidious: "Half of Michigan Blacks Lose Local Power in Detroit Takeover"
When emergency manager Kevyn Orr arrives in near-bankrupt Detroit, almost half of Michigan’s black population will live under the rule of state overseers with little say in the governments nearest them.

...

In downtown Detroit on March 7, Charles Williams II, a reverend, and about 50 supporters protested the emergency- manager law. He used a bullhorn to promise a struggle in the spirit of civil-rights leaders such as Medgar Evers, assassinated in Mississippi in 1963.

I don’t see how it couldn’t be racially motivated," Williams, 30, said of the law.

My first guess is that Williams is lying, but it is possible that he really doesn't see other possibilities. For example, there's an extremely strong correlation between identification as "black" and the political party you vote for. But if the party must be defended at all costs, then the reflex against crimethink will keep you from contemplating that party members might have caused the trouble, and absolutely rule out even dreaming that the party's ideology itself might have some bearing.

Circle the wagons and unfurl every banner; define yourself in every aspect of life as different from the enemy. And if any part of it is holy, all is.

Karzai and Kremlinology

When I heard the report that Karzai had claimed that the US was in league with the Taliban to try to stay longer, the first thing I thought was "I wonder how that fits into his domestic politics?" I should have wondered if the reporters got the story right. I suppose, given the US reaction, that they did. For a change

I know very little of internal Afghan politics, but if I assume that Karzai isn't just running off at the mouth with random truth and nonsense, then this has something to do with restive political allies or opponents he is trying to out-maneuver.

The exercise at hand is how to figure out what's going on without knowing who or what are the powers at play--sort of like the old Kremlinologists trying to figure out the balance of power from the lineup on the reviewing stand at the May Day Parade.

It isn't exactly a surprise that a lot of Afghans would like the US gone, so accusing us of wanting to stay makes Karzai look like he's standing up against Goliath on behalf of the little guys; that should play well. But there are still quite a few Afghans who benefit from having the US and NGO's around--because we're doing good or because they're on the gravy train. Maybe they take the benefits for granted and also support having the US go, but more likely they're on the outs--unpopular with the rest of the Afghans--and Karzai is posturing against them.

The other accusation--that we're in league with the Taliban--suggests that maybe we've been making some concessions/promises to the Taliban that aren't very popular with the rest of the place.

Or I could be all wet: maybe Karzai's middle name is Biden.

Tuesday, March 12, 2013

Black smoke

I gather that Obama did not win the first ballot.

I think it would benefit most reporters to spend 6 months out of the first world with only the electronic access the ordinary people have, so they could escape the US media immersion. Maybe that would help them with a little perspective--but maybe not. They write to an American audience, and it is easier to write to preconceptions than to explain what's really going on. Writing about what's really going on might involve trying to understand it yourself, and that can really slow down writing the story.

Yes, I'm thinking of the conclave reporting. I suspect that Catholics in Pakistan are a little more concerned about the Muslim "anti-blasphemy" riots than whether US nuns get to be priests. Even the well-known problems in the curia(*) tend to be taken out of context.

Probably the only reason for some of these issues to be on the radar at all for a bishop from the Philippines, is that the West controls much of the media.

I think they err in making the same person responsible for administration, pastoral oversight, and theological decisions. The jobs require different gifts. Administration requires a certain flexibility, ability to understand machinery, and will to get things done. Pastoral oversight requires more patience and empathy to correct and guide, preferably without a strong-minded "will to get things done"--that generally gets people's backs up. And theological questions need a good understanding, but holiness most of all--and a reluctance to be flexible with the truth.

Some of the commentators I've read/heard have focused on the "will to get things done" and perceived deficiencies in theology (generally about sex and women), and others concentrate on the requirements for holiness and hopes for a good theologian--and both sorts muse about it being time for a third world pope. The symbolism of a third world pope would be striking. Funny, though. I thought the Catholics were big on things not being symbolic, but the real deal.

(*)When asked how many people work in the Vatican, Pope John is alleged to have responded, “About half.” I wonder how many people know the companion quip. The story goes that someone once asked the Pope if it’s true that his people don’t work in the afternoon. “No, that’s not true,” Good Pope John supposedly replied. “My people don’t work in the morning. In the afternoon, they don’t even come in.”

Saturday, March 09, 2013

Shortcuts to learning and forgetting?

Returning the brain to "adolescent levels of plasticity": learning languages like a child again?

The authors studied Nogo Receptor 1 (NgR1). Why? (I'd never heard of it before.)

Nogo Receptor 1 was originally identified as a mediator of myelin-dependent restriction of recovery from injury . In healthy brain, NgR1 was shown to be essential in closing the critical period for ocular dominance plasticity by single unit electrophysiology in anesthetized mice after monocular deprivation.

Which I gather means that earlier researchers found that the presence of this receptor "restricted" recovery from brain injury. Or maybe the other way around. And that if you cover an eye of an adult mouse, the open eye doesn't become dominant unless you disable these receptors. (I cheated and looked up the paper they referenced--I couldn't figure out what the Akbik et al were trying to say.)

So they tried to turn these receptors off and see what happened with dendritic spines. Normally small spines (tiny growths on the nerves) come and go all the time: only some of them go all the way and turn into synapses. UPDATE for clarification: Memories and learning are built in the brain using synapses. In adults the rate is smaller than in adolescents. So they used some mutant mice without the receptor (I think--their prose is hard to read!) and then appear to have also tried a chemical method of disabling the receptors:

Tamoxifen treatment leads to efficient ngr1 gene rearrangement and near total loss of mRNA and protein within 2 weeks. Mice with floxed ngr1 alleles with or without Actin-Cre-ERT2 transgene were allowed to develop with endogenous levels of NgR1. At P330, the mice received tamoxifen to delete NgR1 from the Cre subgroup. One month later, dendritic spine stability was assessed over 2 weeks. Even at this advanced age, deletion of NgR1 increases dendritic spine turnover to the level observed in adolescent mice

These are mice, hence the rather young "advanced age". "Floxed" means sandwiching a gene between two recombinant sequences, which makes it easy to remove.

They looked at the effects of different monitoring methods. (Apparently putting a tiny window in the skull stimulates spine development.) They looked at sensory deprivation followed by normal sensory experience, and so on.

The bottom line seems to be that without active NgR1 receptors, nerve dendrite spine generation in adult mice is like that in young mice.

Does that mean they learn like young mice? Well, maybe. It seems logical enough, and they tested some learning (using a rotarod), but that isn't very extensive. One thing they noticed was that memories of painful experiences seemed to diminish faster in NgR1-free mice.

Their conclusions include this little tidbit:

Here we show that NgR1 mutants have a decreased threshold for imprinting experience-dependent plasticity and accelerated learning in a motor training paradigm linked to cortical spine turnover. In the setting of rehabilitation, this suggests that antagonizing NgR1 decreases the threshold to reacquire motor skills via plasticity of neuronal connectivity

Or in English, it might be possible to recover more rapidly from nerve damage, maybe even spinal damage, if the doctor can suppress NgR1 activity for a while.

So should we all start taking suppressants before we start taking German?

Well... Apparently NgR1 slows memory loss. So without it... Come to think of it, adolescents aren't that good at remembering chores.

I'd decline to have them monkey with my NgR1.

In the matter of reforming things, as distinct from deforming them, there is one plain and simple principle; a principle which will probably be called a paradox. There exists in such a case a certain institution or law; let us say, for the sake of simplicity, a fence or gate erected across a road. The more modern type of reformer goes gaily up to it and says, "I don't see the use of this; let us clear it away." To which the more intelligent type of reformer will do well to answer: "If you don't see the use of it, I certainly won't let you clear it away. Go away and think. Then, when you can come back and tell me that you do see the use of it, I may allow you to destroy it."

This paradox rests on the most elementary common sense. The gate or fence did not grow there. It was not set up by somnambulists who built it in their sleep. It is highly improbable that it was put there by escaped lunatics who were for some reason loose in the street. Some person had some reason for thinking it would be a good thing for somebody. And until we know what the reason was, we really cannot judge whether the reason was reasonable. It is extremely probable that we have overlooked some whole aspect of the question . . . Chesterton

Tuesday, March 05, 2013

Tribes blue and green

AVI has often written about tribes in America; how they show constellations of features that, though not necessarily related logically, signal membership. The signals extend from music to religion to politics.

I ran across a brief description of the Blues and Greens in Constantinople, and the Nike riots that nearly brought down the emperor. The author wrote

For a long time it was thought that the two groups gradually evolved into what were essentially early political parties, the Blues representing the ruling classes and standing for religious orthodoxy, and the Greens being the party of the people. The Greens were also depicted as proponents of the highly divisive theology of Monophysitism, an influential heresy which held that Christ was not simultaneously divine and human but had only a single nature. (In the fifth and sixth centuries A.D., it threatened to tear the Byzantine Empire apart.) These views were vigorously challenged in the 1970s by Alan Cameron, not least on the grounds that the games were more important than politics in this period, and perfectly capable of arousing violent passions on their own.

I think the answer is "all of the above" and probably some other little fashions as well that never made the history books. What caused the tribes to emerge we'll never know, but they collected emblems to brandish against each other along the way: chariot teams, Christologies, and so forth.

I'd never gotten around to reading Procopius before. His Secret History is sometimes called vicious and slanderous. He certainly has an axe to grind, but when I look around I find that his account is much more plausible than I'd been led to believe. (overuse of "all", "trillion", and apparitions of demons aside) We can find people matching his descriptions of Justinian and Theodora without breaking a sweat--they force themselves on our attention. Not together, and not (yet) with the power the antique pair had, but quite similar otherwise.

For a lighter view of Justinian, check Dr. Boli.

Update: forgot the allegations of philtres. Belesarius' behavior makes a little more sense if his wife Antonina addicted him to something.

Saturday, March 02, 2013

Parsifal

Youngest Son (he likes German) and I went to the Met simulcast of Parsifal this afternoon. The singing was excellent, the casting very good (I especially liked the Gurnemanz, but the Kundry was also great), and the sets interesting. Well, the second act pool of blood was maybe a little distracting. The projections on the rear screen were impressive and generally fit quite well.

I grant you that Gurnemanz' speculations on Kundry's reincarnations are Hindu or Buddhist-flavored, and the compassionate redeemer is a concept also found there. But almost all the prayer gestures were Hindu or Buddhist (or the producer's own imagination), and in no scene (including the elevation of the Grail) was there a cross anywhere--except among the constellation of necklaces Kundry wore. When Parsifal takes the spear, he sings about making a sign, but doesn't make the sign of the cross anymore. The background projections show gigantic planets rising at dramatic times--quite a dramatic accompaniment, but not quite in sync with explicitly Christian lyrics.

And... The sort-of mass with fingers touching lips didn't work--distractingly different. And... The flower maidens trying to seduce Parsifal tried hard, but the pool of blood they sloshed in was distracting, and the seductive stroking of the forest of spears was a little over the top--though I suppose Wagner might have liked that part. And... I didn't think his dunking the Spear in the Grail held by Kundry at the end of the opera was quite the right symbolism for the occasion.

I'd heard the opera before, but not seen it and so this was the first time I understood what was going on. The opera has been called "unstageable", and I think I see what they mean. Very often the music moves at a pace that, while beautiful, leaves people on stage with nothing to do but stand there. Making sure they are able to do something moderately interesting, even if slow, makes a difference.

My better half was listening on the radio--the commentator explained that François Girard's changes were supposed to be an effort at "universal spirituality": what they were was meaningless. The Grail guardian story has elements that aren't quite orthodox, and Wagner's take on it was much less so, but how do you do justice to his vision if you take away half the language?

Parsifal's salvation pivots on rejecting unlawful love, which is a bit of a change-up from some of Wagner's other operas where human love is the sanctifying force.

Despite my list of gripes, I'm glad we went. But I hope somebody can explain to Girard that allergy to Christianity is a fault when trying to stage Parsifal.

Friday, March 01, 2013

Spinning black holes

Things get pretty weird near a black hole, and even more so if it is spinning raidly. The problem is that things falling into a black hole crash around a lot before they vanish, and the debris and energy flying around make it hard to see much inside.

NGC 1365 seems to have a supermassive black hole in it, and ionized iron in its vicinity. The spectrum from the radiating iron has some odd features: are they due to the "frame dragging" around the spinning black hole or some interference from the clouds? Two X-ray space observatories, NASA’s Nuclear Spectroscopic Telescope Array (NuSTAR) and the European Space Agency’s XMM-Newton teamed up to determine that the clouds don't seem to be playing a major role.

If that is true, and the odd features in the iron spectrum are due to general relativistic effects around the black hole, then the thing must be spinning so fast that at its radius it must be moving at nearly the speed of light. I guess you have to collide two black holes or something equally dramatic to get the final one spinning that fast.

One way you can think of the weirdness is that orbiting the thing in one direction is slower than orbiting in the other; time doesn't work exactly the same way in both directions. Yes, it gives me a headache too.

Nobel dreams

The book Nobel Dreams by Gary Taubes is a good description of some of the characters in the UA1 experiment, most notably Carlo Rubbia. I worked on it for a while as a postdoc for David Cline, but didn't get to know as many people as Gary did in a much shorter time.

Both Carlo and David had their sights on a Nobel prize; Carlo got to share one and David didn't.

I remember sitting at the next table over from the two, eavesdropping on them batting ideas back and forth--it was a joy to listen to. They weren't quite such joys to work for, though.

During one of his brief visits to Madison he collared his two postdocs and grad student for instructions. In five minutes he gave me no less than three "absolute top priority" tasks. My better half is less enthused with him. He wanted me to go to a conference in LA and was nonplussed when I pointed out that that was my wife's due date. A few weeks later we had car trouble and my wife came to fetch me at Fermilab, where she met the good professor for the first time. He greeted her with a grumpy "You don't look nine months pregnant."

A colleague says that DOE should fund Cline to just travel around like a bee to pollinate groups with ideas like a traveling conference meeting. His presentations were enthusiastic, expansive, and whirlwind; he could go through a dozen slides in a minute. If talking about his own team's work he had a tendency to overstate accomplishments. . .

At any rate he left Wisconsin for greener pastures at UCLA, and seems to have devoted more time to novel accelerator technologies. His team announced pictures demonstrating that a laser could be used to accelerate electrons. The novelty here is that the laser has to be carefully focused, and that they have some pictures from the Brookhaven facility to prove it works. (An out-of-the-box laser beam has locally strong electric fields, but the push and pull cancel out. You have to play various tricks to take advantage of the available force, and Lawson and Woodward(*) seem to have proved that most of the tricks don't work.)

The laser was about 3 Joules dumped in a beam spot of 50μ. They saw electron accelerations of up to 20MeV, which is good and energetic.

It is nice to see this. It is a long way from being usable for normal particle accelerators--if indeed it is ever possible. The spread of energies is too large. Cline suggests using electrons accelerated by lasers to heat/compress pellets of hydrogen for fusion. Current methods being tried include using focused lasers to superheat the outer shell to create a shock wave to compress the rest of the pellet, capturing laser energy in a cavity to ditto, and so on. I'd not think electron beams would transfer momentum as well as ions, but there might be other effects--I've been wrong before.

The pictures are a little hard to understand without some explanation. The electrons went into a strong magnetic field where their trajectories bent. The faster electrons had straighter paths, the slower ones more curved. When they came out the other side they hit a detector, and the numbers of hits were counted up. The pictures are oriented such that slower electrons would be bent more and wind up at the top of the picture and faster ones be bent less and wind up nearer the bottom. The right hand pictures show more hits near the bottom: faster electrons.


(*) Never heard of them before: I haven't worked on laser acceleration and I've only a vague acquaintance with plasma wake field acceleration.