I completely forgot: four days ago was the 25th anniversary of my arrival in Canada as a landed immigrant. I never had a reason to regret my choice… in fact, politics of the day notwithstanding, I appreciate this country more than ever.
Jul 202012
Jul 202012
43 years ago today, the lunar module (nicknamed Eagle) of Apollo 11 touched down in the Sea of Tranquility, fulfilling a centuries-old dream of humanity.
Too bad that the 40th anniversary of the last Moon landing is rapidly approaching. That, if you ask me, is four wasted decades of manned space exploration.
Incidentally, the book The Eagle Has Landed, by Jack Higgins, was the first English-language book I ever read, sometime in the late 1970s. It was given to me by my aunt (the one who, sadly, is no longer with us) when I complained to her that I was having a hard time improving my English. That particular book, along with several others, was lost when the post office lost a parcel from my Mom. Thanks to Amazon, I managed to replace them all, with one exception: an English-language collection of 11 science-fiction stories that was published in Soviet-era Moscow.
Reading books is a good way to learn a language. My French leaves a lot to be desired (being able to utter a meaningful sentence would be nice) but what little I know I was able to improve by trying to read Jules Verne’s De la Terre à la Lune in French. I first read that book (in Hungarian, of course) at the age of six, in 1969… just as Neil Armstrong and Buzz Aldrin landed on the Moon.
Jul 202012
I just came across a photograph of a building that looks like one of the abandoned edifices in the ghost city of Prypiat, right next to the Chernobyl nuclear power station. Indeed, the picture appeared in a Facebook blog that features many pictures from Prypiat… but this wasn’t one of them.
Instead, the picture was taken in Hungary, on the south shore of Lake Balaton. The building is an abandoned hotel that before the collapse of Communism served as a resort, owned by the Hungarian Industrial Association. I spent nights at that resort. In particular, I spent nights in this very building shown in the picture.
What I found most striking is that the building looks exactly the same as it did 30-odd years ago (except for the decay, of course). It was apparently never modernized. Never really renovated. Presumably, it was privatized some time after 1989, served as a hotel for a while, and then it was abandoned… but it still looks exactly the same (insofar as I can remember) as it did back in the late 1970s.
I guess I now have a better appreciation of how residents of Prypiat feel when they come across present-day photographs of their once proud town. It is an eerie feeling.
Jul 182012
Having been told by a friend that suddenly, there is a spate of articles online about the Pioneer anomaly, I was ready to curse journalists once I came across the words: “a programmer in Canada, Viktor Toth, heard about the effort and contacted Turyshev. He helped Turyshev create a program …”.
To be clear: I didn’t contact Slava; Slava contacted me. I didn’t “help create a program”; I was already done creating a program (which is why Slava contacted me). And that was the state of things back in 2005. What about all the work that I have done since, in the last seven years? Like developing a crude and then a more refined thermal model, independently developing precision orbit determination code to confirm the existence of the anomaly, collaborating with Slava on several papers including a monster review paper published by Living Reviews in Relativity, helping shape and direct the research that arrived at the present results, and drafting significant chunks of the final two papers that appeared in Physical Review Letters?
But then it turns out that journalists are blameless for a change. They didn’t invent a story out of thin air. They just copied the words from a NASA JPL press release.
And I am still trying to decide if I should feel honored or insulted. But then I am reminding myself that feeling insulted is rarely productive. So I’ll go with feeling honored instead. Having my contribution acknowledged by JPL is an honor, even if they didn’t get the details right.
Jul 172012
Imagine you come across a cult whose leaders, either through malice or ignorance, let their gullible followers consume raw sewage. You might not expect gratitude from the cult proper (fanatics are rarely rational) for revealing the truth, but you may expect society as a whole to applaud your actions.
Not when the cult is the Catholic Church and you are in India. Sanal Edamaruku, founder-president of Rationalist International, president of the Indian Rationalist Organization, was recently invited to investigate a weeping statue of Jesus. He found that the weeping was caused, in fact, by a nearby clogged drain and sewer water seeping through walls through capillary action.
You might think this gentleman should deserve some recognition for having saved possibly thousands of believers from the consequences of consuming sewage (they were licking and consuming Jesus’s “tears”).
No… the Catholic Church, in their infinite wisdom, chose to file a complaint instead under India’s penal code alleging that he hurt the religious sentiments of their community.
No wonder it took these superstitious clowns half a millennium to apologize for Galileo.
Hey, you pompous Pope person, perhaps it’s time to open your pie hole and say something on this matter, reining in your nutty followers? Surely you are not this nutty yourself?
And no, I don’t care one iota if anyone’s religious sentiments are hurt by my present tirade. You have a right (a right I am willing to stand up for) to believe whatever nutty fairy tales you want to believe in, but conversely, I have a right to ridicule your nutty beliefs. At least I have that right here in Canada.
Jul 172012
Paris, the city of light, is also known for its cuisine. Why someone would go to Paris and then choose to eat plastic hamburgers at McDonald’s, I have no idea.
But in case culinary reasons are not sufficient to deter you, consider this: next time you go to a McDonald’s in Paris, they may assault you because they don’t like your electronic eyewear. This is what happened to Steve Mann, a well known University of Toronto engineering professor who is a wearable computing pioneer.
I am guessing that McDonald’s chose not to respond to this gentleman’s complaints and reimburse him for the damages that occurred because they enjoy the free publicity.
Perhaps it’s best to avoid McDonald’s restaurants everywhere, just to be safe?
Jul 172012
If you were reading newspapers, science blogs, or even some articles written by prominent scientists or announcements by prominent institutions (such as Canada’s Perimeter Institute), you might be under the impression that the Higgs boson is a done deal: it has been discovered. (Indeed, Perimeter’s Web site announces on its home page that “[the] Higgs boson has been found”.
Sounds great but it is not true. Let me quote from a recent New Scientist online article: “Although spotted at last, many properties of the new particle – thought to be the Higgs boson, or at least something similar – have yet to be tested. What’s more, the telltale signature it left in the detectors at the Large Hadron Collider (LHC) does not exactly match what is predicted”.
There, this says it all. We are almost certain that something has been discovered. (This is the 4.9-sigma result). We are not at all certain that it’s the Higgs. It probably is, but there is a significant likelihood that it isn’t, and we will only know for sure one way or another after several more years’ worth of data are collected. At least this is what the experimenters say. And why should you listen to anyone other than the experimenters?
Jul 162012
I just listened to an interesting story on NPR: how the Red Cross lost (and never regained!) the trust of American soldiers 70 years ago. It’s a cautionary tale about charging for things that were once free, and how that can irreversibly change perceptions.
The Red Cross made a mistake in 1942 when it obeyed a request from America’s then secretary of war and started charging GIs overseas, to eliminate tension that arose because British soldiers had to pay for similar services. Just how bad are the consequences? Seventy years later, when NPR’s reporter told a veteran that the Red Cross still offers donuts for free, the response was predictably skeptical: “stale donuts probably, too”.
Jul 162012
In the last several years, much of the time when I was wearing my physicist’s hat I was working on a theory of modified gravity.
Modified gravity theories present an alternative to the hypothetical (but never observed) substance called “dark matter” that supposedly represents more than 80% of the matter content of the Universe. We need either dark matter or modified gravity to explain observations such as the anomalous (too rapid) rotation of spiral galaxies.
Crudely speaking, when we measure the gravitational influence of an object, we measure the product of two numbers: the gravitational constant G and the object’s mass, M. If the gravitational influence is stronger than expected, it can be either because G is bigger (which means modified gravity) or M is bigger (which means extra mass in the form of some unseen, i.e., “dark” matter).
In Einstein’s general theory of relativity, gravity is the curvature of spacetime. Objects that are influenced only by gravity are said to travel along “geodesics”; their trajectory is determined entirely by the geometry of spacetime. On the other hand, objects that are influenced by forces other than Einstein’s gravity have trajectories that deviate from geodesics.
Massless particles, such as photons of light, must travel on geodesics (specifically, “lightlike geodesics”.) Conversely, if an originally massless particle deviates from a lightlike geodesic, it will appear to have acquired mass (yes, photons of light, when they travel through a transparent substance that slows them down, such as water or glass, do appear to have an effective mass.)
Modified gravity theories can change the strength of gravity two ways. They can change the strength of Einstein’s “geometric” gravity (actually, it would be called “metric gravity”); or, they can introduce a non-geometric force in addition to metric gravity.
And herein lies the problem. One important observation is that galaxies bend light, and they bend light more than one would expect without introducing dark matter. If we wish to modify gravity to account for this, it must mean changing the strength of metric gravity.
If metric gravity is different in a galaxy, it would change the dynamics of solar systems in that galaxy. This can be compensated by introducing a non-geometric force that cancels out the increase. This works for slow-moving objects such as planets and moons (or spacecraft) in orbit around a sun. However, stars like our own Sun also bend light. This can be observed very precisely, and we know that our Sun bends light entirely in accordance with Einstein’s general relativity theory. This cannot be explained as the interplay of geometric curvature and a non-geometric force; photons cannot deviate from the lightlike geodesics that are determined in their entirety by geometry alone.
So we arrive at an apparent contradiction: metric gravity must be stronger than Einstein’s prediction in a galaxy to account for how galaxies bend light, but it cannot be stronger in solar systems in that galaxy (or at the very least, in the one solar system we know well, our own), otherwise it could not account for how suns bend light or radio beams.
I have come to the conclusion that it’s not galaxy rotation curves or cosmological structure formation but modeling the bending of light and being able to deal with this apparent paradox is the most important test that a modified gravity theory must pass in order to be considered viable.
Jul 152012
I just discovered a new Canadian television series: Continuum, on the Showcase channel.
The premise: a group of terrorists (or freedom fighters, depending on one’s point of view) in a corporatist, dystopian future escape execution by traveling 65 years back in time, to 2012. Along with them, a female police officer also ends up in present-day Vancouver.
Back in the old days, discovering something like this mid-season would have been a disappointing experience: not knowing the back story, I might have lost interest. But these are not the old days anymore; all the episodes of Continuum that aired to date can be viewed on Showcase’s Web site.
And they are worth watching. It’s a remarkably good series, and so far, after seven episodes, the quality has not slipped yet. Likable characters, believable effects, and a thought-provoking story. Only three episodes remain from its first season… I hope it gets the green light for a second. Series like this tend to die prematurely even in bigger markets. But then, some of them survive, even in Canada.
Jul 152012
An anniversary I completely forgot about (no, not my wedding anniversary; I’d never forget that!) It was in May 2002, just a little over ten years ago, that I began my Day Book, a term I borrowed from Jerry Pournelle as the word “(we)blog” was not invented yet.
It took me a while to get used to the word “blog”. To be honest, I hated it at first. Later, I told myself to accept the inevitable. Society changes. Culture changes. Language changes. I can either go with the flow or choose to be left behind, prematurely condemning myself to being a grumpy old man. And it’s way too early for that.
Jul 142012
In just over three weeks’ time, the Mars Science Laboratory rover named Curiosity will land on the surface of Mars.
At least that’s what we hope will happen.
The Curiosity landing sequence is extremely complex, using never before tried technologies. The large rover is equipped with a parachute and a giant heat shield when it plunges into the Martian atmosphere. First, it has to discard its heat shield at the right time. Next, its parachute must open. At the right altitude, the parachute must detach, and retrorockets must fire. Then, the rover itself is lowered onto the surface on nylon ropes (effectively, a skycrane mechanism). Then, the ropes must be cut by explosive bolts and the skycrane with the retrorockets must fly away before crashing onto the surface at a safe distance. In this entire sequence, there is very little room for error.
Mars has not been kind to spacecraft. More than 50% of missions to the Red Planet failed. Hopefully, Curiosity will not contribute to that sad statistic. But, it will be a scary landing.
Jul 132012
I have been thinking about neutrinos today. No, not about faster-than-light neutrinos. I was skeptical about the sensational claim from the OPERA experiment last year, and my skepticism was well justified.
They may not be faster than light, but neutrinos are still very weird. Neutrinos of one flavor turn into another, a discovery that, to many a particle physicist, had to be almost as surprising as the possibility that neutrinos are superluminal.
The most straightfoward explanation for these neutrino oscillations is that neutrinos have mass. But herein lies a problem. We only ever observed left-handed neutrinos. This makes sense if neutrinos are massless particles that travel at the speed of light, since all observers agree on what left-handed means: the spin of the neutrino, projected along the direction of its motion, is always −1/2.
But now imagine neutrinos that are massive and travel slower than the speed of light. As a matter of fact, imagine a bunch of neutrinos fired by CERN in Geneva in the direction of Gran Sasso, Italy. It takes roughly 2 ms for them to arrive. Now if you can run very, very, very fast (say, you’re the Flash, the comic book superhero) you may be able to outrun the bunch. Looking back, you will see… a bunch of neutrinos with a velocity vector pointing backwards (they’re slower than you, which means they’ll appear to be moving backwards from your perspective) so projecting their spin along the direction of motion, you get +1/2. In other words, you’re observing right-handed neutrinos.
This is just weird. On the surface of it, it means that our fast-running Flash sees the laws of physics change! This is in deep contradiction with the laws of special relativity, Lorentz invariance and all that.
How we can interpret this situation depends on whether we believe that neutrinos are “Dirac” or “Majorana”. Neutrinos are fermions, and fermions are represented by spinor fields. A spinor field has four components: these correspond, in a sense, to a left-handed and a right-handed particle and their respective antiparticles. So if a particle only exists as a left-handed particle, only two of the four components remain; the other two (at least in the so-called Weyl representation) disappear, are “projected out”, to use a nasty colloquialism.
But we just said that if neutrinos are massive, it no longer makes sense of talking about strictly left-handed neutrinos; to the Flash, those neutrinos may appear right-handed. So both left- and right-handed neutrino states exist. Are they mathematically independent? Because if they are, neutrinos are represented by a full 4-component “Dirac” spinor. But there is a possibility that the components are not independent: in effect, this means that the neutrino is its own antiparticle. Such states can be represented by a two-component “Majorana” spinor.
The difference between these two types of neutrinos is not just theoretical. The neutrino carries something very real: the lepton number, in essence the “electronness” (without the electric charge) of an electron. If a neutrino is its own antiparticle, the two can annihilate one another, and two units of “electronness” vanish. Lepton number is not conserved.
If this is indeed the case, it can be observed. The so-called neutrinoless double beta decay is a hypothetical form of radioactive decay in which an isotope that is known to decay by emitting two electrons simultaneously (e.g., potassium-48 or uranium-238) does so without emitting the corresponding neutrinos (because these annihilate each other without going anywhere). Unfortunately, given that neutrinos don’t like to do much interacting to begin with, the probability of a neutrinoless decay occurring at any given time is very small. Still, it is observable in principle, and if observed, it would indicate unambiguously that neutrinos are Majorana spinors. (A prospect that may be appealing insofar as neutrinos are concerned, but I find it nonetheless deeply disturbing that such a fundamental property of a basic building block of matter may turn out to be ephemeral.)
Either way, I remain at a loss when I think about the handedness of neutrinos. If neutrinos are Dirac neutrinos, one may postulate right-handed neutrinos that do not interact the way left-handed neutrinos do (i.e., do not participate in the weak interaction, being so-called sterile neutrinos instead). Cool, but what about our friend, the Flash? Suppose he is observing the same thing we’re observing, a neutrino in the OPERA bunch interacting with something. But from his perspective, that neutrino is a right-handed neutrino that is not allowed to participate in such an interaction!
Or suppose that neutrinos are Majorana spinors, and right-handed neutrinos are simply much (VERY much) heavier, which is why they have not been observed yet (this is the so-called seesaw mechanism). The theory allows us to construct such as mass matrix, but once again having the Flash around leads to trouble: he will observe ordinary “light” neutrinos as right-handed ones!
Perhaps these are just apparent contradictions. In fact, I am pretty sure that that’s what they are, since all this follows from writing down a theory in the form of a Lagrangian density that is manifestly Lorentz (and Poincaré) invariant, hence the physics does not become broken for the Flash. It will just turn weird. But how weird is too weird?
Jul 132012
Just heard this while listening to the evening jazz program Tonic on CBC Radio 2: a Texas man, whose Austin-Healey convertible was stolen in 1970, found it listed on eBay 42 years later! After a bit of a hassle (mainly because the vehicle’s VIN was misfiled in the FBI’s database) he was able to reclaim it, no doubt much to the distress of the California car dealer who may have bought it in good faith.
Jul 122012
A while back, I ran into a problem with WordPress, the blogging software that I use. I was unable remove posts from categories. In particular, blog posts that were not explicitly added to any category were automatically added to the “Uncategorized” category; it was impossible to remove them afterwards even as I added categories to the post. Unchecking a category made no difference.
Now I know why. For some reason, the WordPress account on my MySQL server lost table lock and (more importantly) delete privileges.
USE mysql; UPDATE db SET Delete_priv='Y' WHERE User='wordpress' AND Delete_priv='N'; UPDATE db SET Lock_tables_priv='Y' WHERE User='wordpress' AND Lock_tables_priv='N'; FLUSH PRIVILEGES;
I really like it when I am able to resolve a long-standing problem with such little hassle. I just hope that this privileges issue did not corrupt the database in other ways, causing grief later on.
Jul 112012
The other day, I came across a picture of Kosmonaut Yuri Gagarin, a floating deep space tracking station operated by the Soviet space establishment in the 1970s. The picture was actually posted to Facebook by The Planetary Society. The source of the photograph is a book, Soviet Robots in the Solar System, published by Springer in 2011.
I felt compelled to buy this book. The Soviet space program always fascinated me. I grew up in the 1960s and 1970s behind the Iron Curtain; yes, we heard about Apollo, but we heard just as much about Soyuz, Vostok, Lunokhod, Venera, not to mention the innumerable spacecraft named Cosmos, followed by a three-digit (later, four-digit) number, whose missions remained shrouded in secrecy.
Of course we now know that many of those Cosmos craft were, in fact, failed missions, including failed missions to Mars and Venus. The Soviets tended to hide their failures and announce missions only when (at least partial) success was already assured.
But it’s not like they were unsuccessful. Sure, they never managed to land a man on the Moon (or even take a human beyond Low Earth Orbit); their attempt to build a launch vehicle comparable to America’s Saturn V, the N-1, failed miserably. But they did land not one but two teleoperated rovers on the Moon decades before the American Sojourner mini-rover arrived on Mars. They experimented with autonomous deep space navigation. They could also claim the first successful soft landing on the surface of Mars (although Mars-3 only remained operational for a few seconds after the landing).
And then there is their most spectacular success story: the Venera series of probes to Venus. Their persistence (and their willingness to tolerate early failures) paid off: Venera 7 successfully reached the Venusian surface, Venera 9 transmitted the first black-and-white images from the planet, followed by the spectacular color panorama captured by Venera 13 and 14.
The tragedy is what happened to this space program afterwards. The US unmanned space program carried on, budget cuts and failures notwithstanding; Voyagers 1 and 2 are still transmitting from the edge of the solar system, a rover has been operating on Mars for the past eight years with another on its way, a probe is en route to Pluto, others are in orbit around Mercury and Saturn. Meanwhile, by the late 1980s, the Soviet unmanned program became a shadow of its former self, only to disappear pretty much completely with the collapse of the Soviet Union and the subsequent failure of Mars-96. More recently, there was hope that the program would be revived with Phobos-Grunt (a hope echoed in the aforementioned 2011 book); alas, that was not to be, as Phobos-Grunt also failed to leave Earth orbit and eventually crashed back onto the Earth (no doubt in the old days, it would have earned another Cosmos designation).
Anyhow, the book by Huntress and Marov arrived in my mailbox today, and apart from what seems to be a higher-than-usual number of trivial typos (one example: “back-and-white”; publishers really had gotten lazy ever since authors started delivering manuscripts electronically) it is a quality book indeed, providing a reasonably complete account of these Soviet efforts. As I am flipping through its pages, I am reminded of those newspaper and magazine articles or the occasional television report (in glorious black-and-white, of course) that captivated me so much as a child.
Jul 102012
According to a recent survey, Hungarians believe they are a minority or threatened majority in their own country. They believe that Hungarians represent only 46-58% of the country’s population, with the rest being mostly Roma (14-21%), Jew (10-12%) or other foreign nationalities (10-11%).
In reality, according to the 2001 census (the latest available), the population of Hungary is 93.2% Hungarian. Roma represent 1.9%, the number of Jews is not known (Jew is not a recognized ethnicity in Europe) but the number of practitioners of Judaism is around 0.1%; and people of foreign nationality (e.g., Arab, Chinese) represent only 0.16%
It is not difficult to guess that quite likely, this cognitive dissonance is closely related to the alarming rise of right-wing nationalism in my country of birth.
Jul 102012
I once had a profound thought, years ago.
I realized that many people think that knowing the name of something is the same as understanding that thing. “What’s that?” they ask, and when you reply, “Oh, that’s just the blinking wanker from a thermonuclear quantum generator,” they nod deeply and thank you with the words, “I understand”. (Presumably these are the same people who, when they ask “How does this computer work?”, do not actually mean that they are looking for an explanation of Neumann machines, digital electronics, modern microprocessor technology, memory management principles, hardware virtualization techniques and whatnot; they were really just looking for the ON switch. Such people form an alarming majority… but it took me many frustrating years to learn this.)
I am not sure how to feel now, having just come across a short interview piece with the late physicist Richard Feynman, who is talking about the same topic. The piece is even titled “Knowing the name of something“. I am certainly reassurred that a mind such as Feynman’s had the same thought that I did. I am also disappointed that my profound thought is not so original after all. But I feel I should really be encouraged: perhaps this is just a sign that the same thought might be occurring to many other people, and that might make the world a better place. Who knows… in a big Universe, anything can happen!
Jul 092012
I didn’t realize that the first ever photograph of the Earth taken from space predates Sputnik by more than a decade.
This amazing picture is one of several frames shot by a camera on board a captured V-2 rocket, launched from the White Sands Missile Range on October 24, 1946. Almost 66 years ago.
Amazing.
Jul 072012
Not exactly a typical weather report for Ottawa: “blowing dust”. I know it’s been a dry summer so far, but even so… what next, a sandstorm?