unixronin: Peter Sellers as Dr. Strangelove (Dr. Strangelove)
Wednesday, September 21st, 2011 04:08 pm

We still hear a lot about consensus about climate change, and yet when you talk to people at large, it's still pretty clear there is none, outside of a few scientific circles.

One of the big problems, I think, is that the debate has become polarized into two political camps — "Of course it's all anthropogenic" and "Nonsense, it can't possibly be anthropogenic, the planet is just too big."  There is no middle ground of "Let's try to determine how much of this change may be anthropogenic", because the careful middle-grounders have been shouted down by the climate change deniers on one hand and the ZOMG-technology-is-BAD crowd on the other.  Each camp spreads lies and disinformation about the data, and particularly about the other side's data.

For instance, most of the most outspoken climate change deniers I know insist that the possibility of climate change is rubbish because it's all based on baseline data that starts in 1960.  (It isn't.  But repeat the lie often enough, and you'll convince people who are willing to take your word on other matters.)

Another common anti-climate-change canard is "What, this prediction of the whole planet's climate a hundred years ahead comes from the people who can't accurately predict the weather in my neighborhood three days in advance?"

Well, actually, no, it doesn't.  And in any case, that's a different and only superficially related problem.  Trying to predict chaotic short-term local fluctuations in a tiny part of a large system is actually a much more complex and difficult problem than analyzing and projecting trends in the long-term, large-scale average state of the entire system.

To give an admittedly inexact analogy, if I build a giant pachinko machine out of two-by-twelves and half-inch rebar, and I pour a 55-gallon drum of marbles into the top of it, I have a very, very slim chance of being able to predict exactly which marbles are going to be bouncing off a specified pin ninety seconds from now, and in which direction.  However, I can unequivocally state that the general trend is going to be for the marbles to proceed downwards, and I can predict with almost complete confidence that five minutes from now, all or almost all of those fifty thousand marbles (or however many marbles fit into a 55-gallon drum) are going to be in the bin at the bottom of the machine.  (But there's always the possibility my deck could collapse, at which point all bets are off.)

"The planet is just too big"?  Yeah, well, they said that about the oceans, didn't they?  "We can just dump trash and sewage into the oceans without repercussions forever.  They're so huge we could never affect them."  "We can fish the oceans forever.  The oceans are vast, and their supply of fish is inexhaustible to all practical purposes."  Tell that to Newfie fishermen who watched their livelihood vanish when the Grand Banks crashed, or to Peruvian anchovy fishermen after that fishery crashed from massive international overfishing (mostly in order to grind the anchovy up for fish-meal fertilizer).  Take a look at the annual dead zone in the Gulf of Mexico from fertilizer runoff down the Mississippi.  Fer cryin' out loud, the BP Deepwater Horizon blowout left an oil slick on the Gulf that was naked-eye visible from orbit.  Look how polluted the Mediterranean Sea has become, with the entire effluvium of North Africa and most of southern Europe draining into it.  Look at the tundra of Siberia and the Canadian arctic: the permafrost is thawing.  Oh, yes, we can SO affect the planet as a whole, and anyone who thinks otherwise is suffering from dangerous delusions or dangerous ignorance.

The other side of the argument, of course, is the anthropogenic-climate-change-is-holy-truth, how-dare-you-question-it camp who deny any possibility that any part of what we can see happening around us could possibly be natural.  "This has never happened before!"  Well, yes, actually, it has.  Repeatedly.  We don't know what the trigger factors were then.  We have some idea this time.  "The Earth's climate has been stable for millions of years until we came along!"  Well, no, actually, it hasn't.  It's at best metastable, and even if it had been, "millions of years" is an eye-blink in Earth's history.  The dinosaurs alone were around for about 160 million years.  They sneer at your "millions of years" — or would, if they hadn't gone suddenly extinct, apparently due to a series of global changes they couldn't adapt to.

Oh, and while we're on the subject, you folks in the climate-change-zealot faction in the scientific community:  I hope you're aware that your shrill efforts to shout down and suppress any contrary opinions from the scientific community probably did more to discredit your position and make the man in the street question your conclusions than anything your most vocal opponents ever managed.  That wasn't the smartest thing you ever did, you know?

(Counterpoint to that:  about that anti-climate-change petition that's going around in the news?  The one allegedly signed by 31,000 "scientists"?  Word is nearly 9,000 of those "scientists" actually have real Ph.Ds.  Still no word yet on whether any of those 9,000 are actually climatologists.  What, you tell me, over a thousand behavioral psychologists say they don't support climate change theories?  Right.  Duly noted.  I'll be sure to consult a proper seismologist next time I need some psychological advice.)

What we need to do is acknowledge three things, really:

  • There is a large and growing body of evidence that the Earth's long-term (from our viewpoint) average climate is changing in ways that are likely to severely impact our way of life, and possibly our ability to feed large subsets of the human race.  Yes, periodically certain subsets of that data have been shown to be in error.  That doesn't invalidate all the rest of the data.  No, it's not conclusive yet.  But if we wait until it is conclusive before we start doing anything, and it turns out it IS drastically changing in ways that are bad for us, we're pretty much fucked.
  • We don't know for sure how much of this we have caused, but it would behoove us to do our best to find out, so that we can avoid making unplanned changes to it in future.
  • And last, REGARDLESS OF THE CAUSE, we need to get to work on figuring out viable approaches for controlling and mitigating such changes, without trying to roll back the green-fantasy clock to some kind of bucolic pastoral Utopia that has never actually existed, so that we can try to maintain our planet in a general climatic realm compatible with the continuance of modern civilization as we know it.  This isn't going to involve abandoning technology; it has to involve leapfrogging to clean technology.  (And just don't get me started on that "clean coal" bullshit.  Talking about "clean coal" is like talking about hot ice or lightweight lead.)
unixronin: Astronaut on EVA (Space)
Friday, July 8th, 2011 11:47 am

Flawless launch.  They nailed it perfectly.

unixronin: A somewhat Borg-ish high-tech avatar (Techno/geekdom)
Tuesday, July 5th, 2011 11:36 am

There's an interesting example of confirmation bias in the back of the July Scientific American, which is amusing because it comes just two pages after Michael Shermer's column in which he talks about confirmation bias and why skepticism is important to science.  The article asserts that child mortality rates decline as women become better educated, and asserts that this is becauseeducated women "make wiser choices about hygiene, nutrition, immunization and contraception".

Here's the online version of the article.  Notice anything about it?

Look carefully. Pay particular attention to Niger, Paraguay, Fiji, Namibia, Tonga, the Marshall Islands, New Zealand, Ukraine, the Phillipines, Burkina Faso, Ethiopia, Chad, Saint Lucia, Equatorial Guinea.  Compare to, say, the Maldives, Portugal, Nepal, Montenegro. Once I've pointed these out, I'm sure you should be able to find other similar examples.  There's a lot of them.

So what do these examples I've pointed out show?

Well, it's more what they DON'T show.  Which is to say, there is no clear correlation between increases in education of women and decreases in child mortality. Some of these have significant increases in length of education with virtually no change in child mortality.  Some have almost no change in education and significant decreases in child mortality. Some show little change in either.  Some countries with almost no improvement in education show larger decreases in child mortality than other countries in which female education increased much more.

Gambia, for example, started out in 1970 with a higher child mortality rate than nearby Ghana, yet improved its child mortality rate by 2009 twice as much as Ghana did, even though Ghana had around twice the improvement in education.  During the same period, Nigeria and the Marshall Islands both improved their education just as much as Ghana did, with no change whatsoever in child mortality.  Somalia and Rwanda both had significant improvements in child mortality, while Equatorial Guinea, which improved education twice as much as either, showed no child mortality reduction at all. Chad improved childhood mortality more than Equatorial Guinea did, despite almost no improvement in education and an ongoing civil war, while Burkina Faso showed more child mortality reduction with even less improvement in education. Niger matched Burkina Faso's gains despite no improvement in education at all.  Turkmenistan and neighboring Uzbekistan show almost identical improvements in education, but Turkmenistan shows an almost 3:1 drop in child mortality while Uzbekistan's hardly changed.  Child mortality plunged in Afghanistan while education of women remained static.  Fiji made smaller gains in child mortality than Australia, despite larger gains in education.  Samoa and nearby Tonga improved their education by almost the same amount, but Samoa's child mortality rate declined, while Tonga's did not.  Both are eclipsed by Vanuatu, which improved education less than either.  Portugal improved child mortality twice as much as next-door Spain, on almost identical improvements in education.  Guyana vs. Haiti, Chile vs. Uruguay, Saudi Arabia vs. Lebanon.  Bosnia-Herzegovina and Montenegro, despite two Balkan wars, left the much wealthier Russian Federation and Ukraine in their dust.  War-torn El Salvador passed Mexico by, while Panama scarcely improved.

The authors of this study desperately want to find a causative link between education of women and reduced child mortality.  However, their published results do not support their conclusion.  There exists a correlation, yes — albeit a weak one — but correlation does not imply causation.  In fact, what all of these results have in common is that decrease in child mortality is more strongly correlated to time than it is to improvements in education of women.

Time alone, of course, doesn't do anything, and cannot be responsible.  But it makes a nice control.  There is another factor at work here, probably several other factors; but the authors do not appear to have looked for them, because they want their explanation to be right.  But when your results appear to show that your data is actually more weakly correlated to your proposed cause than it is to time alone, you have a credibility problem.

unixronin: Richard Feynman (Richard Feynman)
Monday, April 11th, 2011 08:25 am

Thought for the day:

Neils Bohr once challenged Albert Einstein to prove that the moon exists when no-one is observing it, after Einstein asked him whether he could really believe that it doesn't.

I don't have the math chops to do it.  But, I believe it can be shown that for the Moon to not exist except when being observed would violate local causality.  This is because the Moon is approximately 1.25 light-seconds away, and thus in order to be observable, the Moon would have to consistently begin existing at least 1.25 seconds before being observed.

(There is also a problem with the fact that the Moon exists in a specific, definable location, implying that it has independent existence even when not being observed.  If we could call the moon into being simply by observing it, why can't we just observe it anywhere we choose, at any moment that the whim takes us?  The simple fact that we can only observe the Moon "where it is" argues rather strongly that it, in fact, is.)

unixronin: Richard Feynman (Richard Feynman)
Wednesday, December 1st, 2010 03:54 pm

yesterday, NASA really stirred people up with a cryptic announcement of a press conference relating to astrobiology.  Today, this NASA blog post has quieted a little of the speculation.

The conference, it turns out,. will discuss the issues relating to "shadow biospheres" with different biochemistry.  And it's about damned time!  I've been lamenting for ... well, decades now, really, that the search for "extra-terrestrial life" was being too narrowly confined to a definition of life that really means "Earth-type life".  All the basic assumptions included the unspoken assumption that all viable biospheres must be Earthlike, and all possible biochemistries built upon the same chemical basis as our biochemistry.  Many learned scientists have declaimed at length upon the pronunciation that a CHONP-based biochemistry is the only possible one, because it's what works here, and all the alternative biochemistries people have proposed won't work here.

Except of course, that in recent years we've found different biochemistries right here on Earth.  Metabolic cycles based upon oxidizing sulfur, for example, that are viable only within deep-sea black smokers.  What happens on a planet where the predominant environment is like that of a black smoker?  And as the blog points out, this article in the International Journal of Astrobiology asks whether our planet could as easily have gone down the path of using arsenic instead of phosphorus, and points out that arsenic is toxic to us precisely because it so easily — yet not exactly — substitutes for phosphorus.

Who knows what could be a viable biochemistry in, say, a methane-hydrogen atmosphere under two hundred bar of pressure at 160K?  Or perhaps an atmosphere of sulfuric acid vapor at two bar and 900K? We for sure don't know.  We haven't even tried to find out.

unixronin: Richard Feynman (Richard Feynman)
Wednesday, November 24th, 2010 02:54 pm

THIS is just ... brilliant.  (And the pun wasn't intentional.)  A group at the University of Bonn in Germany has figured out an ingenious trick to accomplish a stunt previously believed impossible:  They have created a Bose-Einstein condensate OF PHOTONS.

...Well played, sirs!

unixronin: Richard Feynman (Richard Feynman)
Monday, November 15th, 2010 10:52 pm

The Chandra X-Ray Observatory has found evidence of "the youngest black hole known to exist in our cosmic neighborhood".  This is being fairly widely reported across the 'net and elsewhere.

Unfortunately, it's being badly reported.  The typical report says that this black hole is 30 years old.  But it's not.  It's fifty million light-years away in the galaxy M100, and we are "seeing" it by X-rays it emitted fifty million years ago.

There is a convention that when describing astronomical objects, "age" means "the age it was when it emitted the light we're seeing it by".  But the general press not only is seldom aware of this convention; it seldom understands the difference.

I propose the explicit use of a new term:  observational age.  We would say that an astronomical object — in this case, the black hole — has an observational age of 30 years, specifically stating that we are observing it as it was when it was 30 years old.  It's actual age, of course, is about fifty million years; but we won't observe it that way for another fifty million years, unless we invent a faster-than-light stardrive at some point along the way.  Any astronomical body within our solar system has an observational age equal to all practical purposes to its actual age, since the observational lag to it is so many orders of magnitude smaller than even our error bracket for its actual age.  When you have a planet five billion years old give or take half a billion years, who's going to waste time quibbling about a couple of minutes to a few hours?

unixronin: Richard Feynman (Richard Feynman)
Saturday, October 16th, 2010 11:54 pm

From November 2006, a Google Tech Talk from Robert Bussard about inertial electrostatic confinement fusion and the hydrogen-boron fusion cycle, along with some interesting commentary on such things as why government programs are actually preventing progress on fusion and why ITER will never work.

unixronin: Gene Wilder in Young Frankenstein (Mad science)
Wednesday, September 29th, 2010 02:16 pm

Nope.  It's Frankenbooster, a proposal to get a family of heavy-lift boosters operational fast by reusing Space Shuttle parts.  The low-end configuration mates three SSMEs to a Shuttle external tank, straps two Shuttle solid boosters on each side, and puts a payload capsule atop the tank to lift 70 tons to orbit.  Other proposed configurations lift 100 or 130 tons.

unixronin: A somewhat Borg-ish high-tech avatar (Techno/geekdom)
Friday, September 24th, 2010 02:58 pm

Cnews is reporting that a University of Toronto student has built and successfully flown a human-powered aircraft with flapping wings.

Look at the video, though.  It can't get airborne under its own power; it gets off the ground only by virtue of a cable tow from a vehicle.  According to the article,

[...] Reichert climbed aboard, flapped its massive wings through a system of pulleys by pedalling his feet, and took off, sustaining altitude and airspeed for 19.3 seconds, and covering a distance of 145 metres at 25.6 km/h.

Um ... no.  That's not what appears to be shown in that video.  What that video shows is Reichert's "Snowbird" being towed aloft, then, after the tether is dropped, being apparently unable to maintain airspeed (though it is admittedly difficult to judge from this angle) and, shortly, altitude after he runs out of airspeed.  I would venture to bet that a half-decent sailplane designed for speeds that low could have glided further from that initial tow than Reichert's craft was able to stay aloft.

My call?  Sorry, but I see this less as a human-powered aircraft, than as an ultralight sailplane that — once towed aloft — manages to stay briefly aloft not because of, but in spite of its flapping-wing mechanism.

Show me a "human-powered" flapping aircraft that can actually take off — even briefly — under its own power, like the human-powered Gossamer Condor, and then I'll be impressed.  But a "human-powered aircraft" that manages to glide less than 500 feet after being towed to what looks like about 20 feet altitude by a car?  Honestly, a 25:1 glide ratio is pretty shabby these days.  That's 1930s glider performance.  Modern open-class sailplanes, despite smaller wingspans and much greater weight than the Snowbird, can achieve almost three times that.  With 32m of wing and so little weight, Snowbird's glide performance should be phenomenal, not mediocre.

It's a start, and it's closer than anyone else has come yet.  But I won't consider it a human-powered aircraft until it can get itself airborne by human power alone.

unixronin: Nuke the Zerg until they glow (animation) (Boom Today)
Tuesday, September 21st, 2010 01:10 pm
unixronin: Astronaut on EVA (Space)
Wednesday, September 8th, 2010 01:27 pm
unixronin: Richard Feynman (Richard Feynman)
Tuesday, September 7th, 2010 11:40 pm
unixronin: Richard Feynman (Richard Feynman)
Saturday, September 4th, 2010 05:44 pm

New data from the Hubble telescope since the Space Telescope Imaging Spectrograph was repaired last year are showing some interesting behavior in the debris bubble surrounging the site of supernova 1987A, in the Large Magellanic Cloud, one of the two largest dwarf galaxies surrounding the Milky Way.

Supernova 1987A is surrounded by a ring of debris that was thrown out by the star 20,000 years before it exploded into a supernova.  The team's most recent observations of hydrogen radiation in the visible and ultraviolet spectra show that emissions from the supernova are brighter than those observed in 2004.  The researchers suggest that the shock waves of gas sent out by the supernova are brightening the ring of debris round it.

They also think that some of the shock waves are bouncing back off the debris. The team has used Hubble's imaging spectrograph to map the velocity and chemical composition of this moving gas.

"Although we always knew it was there, this is the first time we've actually been able to see this reverse shock [in supernova 1987A]", says Richard McCray, an astrophysicist at the University of Colorado and a co-author on the study.

Having a supernova occur practically in our back yard, while we were watching, has been a treasure trove of data for astronomers studying supernovae.

In unrelated news, sophisticated new measurements of G, Isaac Newton's Universal Gravitational Constant, have reported a value of 6.67349 × 10−11 m3 kg−1 s−2, with an uncertainty of 26 parts per million.  That doesn't sound much different from the previously accepted value of 6.67234 × 10−11 m3 kg−1 s−2 with uncertainty of 21 parts per million; but in this context, it represents a discrepancy of ten standard deviations, and that is huge.

The meaning of this discrepancy is not currently known.  But it does raise an interesting speculation:  What if the Universal Gravitational Constant is not, in fact, constant?  What would be the effect upon the behavior and evolution of the universe if there were a miniscule gravitational tide in the universe, and the value of G depended upon when you measured it — or perhaps if it depended upon where you were when you measured it?

unixronin: A somewhat Borg-ish high-tech avatar (Techno/geekdom)
Friday, September 3rd, 2010 08:28 am

Via Bruce Schneier:  A team of cryptologists at the University of Trondheim, Norway, have developed a successful attack that works against both currently-deployed existing quantum cryptographic systems, IDQ and MagiQ.

The attack, which allows an eavesdropper (traditionally "Eve") to completely recover all quantum-encrypted data sent over the link, completely invisibly to the recipient (traditionally "Bob"), is brilliantly simple:  Eve simply blinds Bob's quantum detector with a 1mW laser, preventing it from operating as a quantum device capable of detecting single-photon polarization, then intercepts all the entangled photons and reads them herself.  Eve then resends every 1 bit to Bob as a bright laser pulse, which Bob's detector, blinded for quantum events, responds to in classical mode and reads as a 1.  Bob's detector — and Bob — cannot tell the difference.

"We have exploited a purely technological loophole that turns a quantum cryptographic system into a classical system, without anyone noticing," says Makarov.

Quantum encryption has been widely considered, and widely touted as, unbreakable because the laws of physics guarantee that you cannot measure any property of a quantum system without detectibly disrupting the system.  Thus it has been taken as gospel that you cannot eavesdrop on a quantum communication channel without leaving clear evidence that you have done so.  This inspired piece of lateral thinking is a Kobayashi Maru strategy — faced with an unwinnable game, Makarov's team have simply changed the rules of the game to one that they can win.

unixronin: Galen the technomage, from Babylon 5: Crusade (Default)
Thursday, August 5th, 2010 09:02 pm

SpaceX has made some recent announcements, here reported in Aviation Week, for future plans to extend and develop its Falcon booster line all the way to a Falcon XX heavy-lift vehicle larger and more powerful than a Saturn V, capable of lifting as much as 140 metric tons to low Earth orbit.  SpaceX's propulsion engineers have apparently also urged NASA to resume development of NERVA for manned interplanetary missions, and senior SpaceX personnel have declared, "Mars is the ultimate goal of SpaceX."  There's considerable discussion on the forums at nasaspaceflight.com.

Some sample images from the SpaceX presentations:

(Copied, not linked, because the original source URL is a nasty ugly PHP thing that make things go all asplody.)

unixronin: Galen the technomage, from Babylon 5: Crusade (Default)
Friday, July 30th, 2010 12:46 am

Hogamous, higamous, man is polygamous;
Higamous, hogamous, woman's monogamous.

Or so runs the traditional doggerel.

"Bullshit", says psychologist Christopher Ryan, co-author of "Sex at Dawn: The Prehistoric Origins of Modern Sexuality".

This is a problem because there is no reason to believe monogamy comes naturally to human beings.  In fact, for millions of years, evolutionary forces have cultivated human libido to the point where ours is arguably the most sexual species on Earth.

unixronin: Richard Feynman (Richard Feynman)
Tuesday, July 6th, 2010 01:22 pm

Have you ever wished you could see what our galactic neighborhood looks like in the X-ray band?  Or in gamma rays, or microwaves, or deep infra-red?

Well, now you can.
unixronin: Richard Feynman (Richard Feynman)
Tuesday, June 15th, 2010 02:15 pm

In case anyone missed it (it really hasn't hit the non-scientific news in a big way, which isn't that surprising), the OPERA experiment at Gran Sasso National Laboratory, Italy has detected — with 98% confidence, they say — a tau neutrino in a beam of muon neutrinos fired from CERN, roughly 732km away.

Well, so what?  One tau neutrino among billions of muon neutrinos.  No big deal, right?  Everyone makes mistakes?

Well, here's why it's a big deal:  The originating beam from CERN is known to contain solely muon neutrinos, because the process that creates the beam can emit only muon neutrinos.  This means that in only 732km, a trip lasting 2.4 milliseconds, one of those muon neutrinos changed into a tau neutrino.  And that's important because it means that neutrinos, long believed to be massless, must in fact possess rest mass, be it ever so tiny a mass.

And that may not sound like a lot, but believe me, it's a lot more important than it sounds — not least because it's another datum that means the Standard Model of particle physics is, at best, incomplete, because the Standard Model as it currently exists does not allow the possibility of neutrinos having rest mass.  This is at least the third recent major result to throw serious doubt upon the Standard Model.  (Others include the recent result showing significant matter/antimatter asymmetry from the DZero experiment at Fermilab's Tevatron facility, and the Brookhaven muon (g-2)experiment to measure the anomalous magnetic moment of the muon, which yielded a result 2.6 standard deviations outside the range possible under the Standard Model.  This latter result also possibly presents experimental evidence in support of the theory of supersymmetry.)

It's an interesting footnote that from the day they began drawing up the blueprints for GSNL, the precise location and alignment of the laboratory were chosen specifically to facilitate constructing this experiment.

unixronin: Richard Feynman (Richard Feynman)
Thursday, June 3rd, 2010 05:45 pm

Well, this Astronomy Now article is a pretty complete summary.  You probably also want to follow the link to this article from last June, which talks about Betelgeuse's accelerating shrinkage over the period from 1993 to 2009.