I was never much of a believer in negative cop stereotypes nor do I believe that the “powers that be” are conspiring to get you. But today’s revelation that the RCMP agents who tasered Robert Dziekanski to death last year were in fact flat our lying to the official inquiry is enough to make even the staunchest opponent of conspiracy theories blink. The word “outrageous” doesn’t even come close to describing it.
Republicans in the US are criticizing Obama for his hands-off approach concerning the events in Iran.
So here is my question: what, exactly, do Republicans want?
Do they want to help Iran? Because in that case, the best thing to do is to shut up. Twenty years ago another Republican, the elder President Bush, explained in an interview why he did not go to gloat and “dance on the top of the Berlin Wall”: because if anything, it would have just encouraged the ruling elites of the East Bloc to crack down instead of facilitating a largely peaceful transition to democracy. The same is true today: loud protests by Obama about election fraud and crackdowns in Iran would only help the ruling elite.
Do Republicans not realize this? I doubt that they are that dumb. But then, I have to conclude that they are just turning this, along with everything else, into a partisan issue. They couldn’t care less as to what happens in Teheran, so long as they can bash Obama.
Hmmm, there’s an even worse alternative. Perhaps they actually want the ruling elite in Teheran to stay in power. How else could they continue to demonize Iran, and Islam in general?
I am reading a very interesting document: the results of an “uncensored survey”, conducted by Terror Free Tomorrow: The Center for Public Opinion in the days leading up to Iran’s elections.
If I interpret their chart on page 8 of the PDF report correctly, 78% of the respondents they interviewed indicated an intent to vote. The number of eligible voters being 100%, 34% expressed support for Ahmedinejad, 14% for Moussavi, 3% for the other two candidates, while 27% were still undecided. If I divide up the undecided equally between Ahmedinejad and Moussavi, I get 61% vs. 35% of the total number of votes cast, with 78% participation.
The actual, official result was 85% participation, with 62.63% voting for Ahmedinejad and 33.75% for Moussavi; the difference is statistically insignificant.
It would be the ultimate irony if Iran’s theocratic regime was brought down by accusations of widespread electoral fraud yet no actual fraud had taken place.
David Letterman finally apologized for the joke he made last week about Sarah Palin and her daughter, a joke that was clearly in bad taste.
When I first heard about Sarah Palin, just after it was announced that she would be the running mate of John McCain in 2008, I remember the disbelief that I felt. Whatever temporary insanity possessed the inhabitants of Alaska when they elected her (or is it just that we live in an era of political populism, be it the case of the once small town mayor now popular governor of Alaska or, say, the once Teheran mayor now popular president of Iran?) my immediate reaction when I saw governor Palin and her family on television was to wonder if I might have accidentally set on my remote and switched to The Jerry Springer Show without noticing. Everything about governor Palin: her mannerisms (including how she manages to include wannabe beauty queen phrases like “the great state of Alaska” into every second sentence she utters), her family life, the names she gave to her children… about the only thing missing from the picture was a fight on stage, to be broken up by security.
Now I don’t wish to fall into the same trap as Letterman… family members, especially underage family members of a politician are not fair game, not even for late night comics. Yet, if the Palin family accurately reflects “conservative family values”, then perhaps it is appropriate to question the validity of those values, and possible to do so without insulting unwitting members of the Palin family. On the other hand, if the Palin family does not accurately reflect conservative family values, then perhaps it is right to accuse conservatives of hypocrisy, again without ad hominem insults.
Chances are that if you are reading this, especially if you are reading this through Facebook, you are not located in Iran.
Presidential elections in Iran are over, and the people have spoken: Dr. Ahmedinejad has been reelected with a landslide.
At least that’s what the Iranian government would like you to believe. Desperately. Which explain’s Ahmedinejad’s farce of a press conference, or the fact that lines of communication to/from and within Iran are increasingly being shut down by the Iranian authorities. And now there is a massive demonstration being held in favor of the newly reelected president, while his main opponent, Moussavi, is nowhere to be seen, presumed by some to be under house arrest.
So here is what I am wondering about: is Ahmedinejad about to turn into a Ceaucescu on us? Ceaucescu did the same thing, held a massive rally in the town of Timisoara to demonstrate that he has the support of the people. Well… he didn’t.
Does Ahmedinejad have the needed support to maintain his position in the Islamic Republic, a state with a split personality that pretends to be democratic, yet rejects what they call “liberal democracy”?
My bet was on lightning, but perhaps I was wrong: it appears that there is good reason to believe that the in-flight breakup of Air France 447 was due to the pilots’ struggle to stay in control of an airplane with a faulty speed sensor.
23 years ago today, I left Hungary and registered as a political refugee in Austria. I started my new life with a suitcase full of clothes, and a little less than $1,000 in my pocket.
Yes, it was worth it.
According to Wikipedia, absolutely nothing else notable happened on this day in 1986.
Almost forgot. It was a Thursday.
I was channel-surfing for news this morning, and I caught a segment on CTV’s morning show about “dirty electricity”.
I shall refrain from calling the gentleman being interviewed using a variety of unflattering names, because it would not be polite, and in any case, it’s not the person but the message that I take issue with.
Basically, he put a bunch of electronic devices like cordless phones, baby monitors, Wi-Fi routers or even fluorescent light bulbs on a test bench, plugged them in, and then held a contraption with an antenna and a speaker close to them. The contraption was making loud noises, from which this gentleman concluded that these devices “emit radiation”, and “send dirty electricity back through the wires”.
So then… what? The whole Universe is emitting similar radiation at radio frequencies. Any warm object, including the walls of your house, emits radiation at such frequencies and higher. And why should I care?
Of course, it helps dropping a few scary phrases like, “skyrocketing rates of autism”. Oh, he wasn’t saying that they are related. Why should he? Merely mentioning autism while he’s talking about “dirty electricity” is enough to suggest a connection.
Just to be clear about it, almost all electronic devices emit radio frequency radiation that can then be picked up by a suitable receiver and converted into loud and scary noise. When I was 10 or so and got my first pocket calculator, I had endless fun holding it close to an AM receiver and listening to its “song”. Later, when I had my first programmable calculator, I could tell by listening to the sounds on a nearby radio if it was still executing a program, or even if it displayed the expected result or just showed an error condition. Modern calculators use so little power that their transmissions cannot be picked up so easily, but does this mean that the old calculators were a health threat? Of course not.
At such low frequencies, electromagnetic radiation does not interact with our bodies in harmful ways. To cause genetic damage, for instance, much shorter wavelengths would be needed, you need to go at least to the ultraviolet range to produce ionization and, possibly, damage to DNA. At lower frequencies, most emissions are not even absorbed by the body very effectively. The little energy that is being absorbed may turn into tiny currents, but those are far too tiny to have any appreciable biological impact. Note that we are not talking about holding a cell phone with a, say, 0.3W transmitter just an inch from your brain (though even that, I think, is probably quite harmless, never mind sensationalist claims to the contrary); we are talking about a few milliwatts of stray radio frequency emissions not mere inches, but feet or more from a person.
As to “dirty electricity”, any device that produces a capacitive or inductive load on the house wiring will invariably feed some high frequency noise back through the wiring. Motors are the worst offenders, like vacuum cleaners or washing machines. Is this a problem? I doubt it. House wiring already acts as a powerful transmission antenna, continuously emitting electromagnetic waves at 60 Hz (in North America); so what if this emission is modulated further by some higher frequency noise?
But even if I am wrong about all of this, and low-frequency, low-energy electromagnetic radiation has a biological effect after all… study it by all means, yes, but it is no excuse for CTV to bring a scaremongerer with his noisy gadget (designed clearly with the intent to impress, not measure) on live television.
Being self-employed means, among other things, that I am not just using my computer systems, I am also responsible for managing them.
On the second Tuesday of every month, Microsoft releases a batch of fixes. These fixes are important: they address known security issues among other things, and some of these issues may already be actively exploited by viruses or malicious Web sites. I prefer installing these updates by hand, because doing so allows me to test the updates on a test computer before putting them on “mission critical” machines. Also, my work is not interrupted by degraded system performance while an update is being processed, or by a sudden request by Windows to reboot.
A few months ago, I allowed Windows Update to install a bunch of Windows Live features on my main workstation, not because I needed them but, well, because they were available and they could do no harm, right? Well, they didn’t do any real harm, except for the annoying little issue of an Explorer window always opening up when I started the system, with the folder C:\Program Files\Microsoft, which contained just one subfolder called Search Enhancement Pack. So yesterday, since I was installing updates and rebooting the system anyway, I decided to do whatever it takes (short of reinstalling Windows, that is) to get rid of this thing.
Having done some research on Google, I decided to try a few promising-looking solutions. First, I used a command-line uninstallation command to get rid of a component called Choice Guard, which supposedly caused this folder to be opened on startup. Reboot… no cigar, the folder was still there.
One file in the folder in question was SeaPort.exe, a service component of the Search Enhancement Pack. On a hunch, I disabled this service and rebooted. Again no cigar… the folder was still there.
Then, I found the command-line command to actually uninstall the whole Search Enhancement Pack. I was sure that this would do the trick… but it didn’t. After reboot, the folder was still there.
OK, I don’t have time for this silliness, I thought, it’s time to get rid of all this Windows Live nonsense that I won’t be using much anyway. I uninstalled them all except for the Windows Live Onecare component. Reboot, and… the stupid folder was still opened by Explorer on startup.
Time to get rid of Onecare, too. I did, and rebooted… and once again, Explorer opened the folder. Mind you, by this time the folder contained only one file in a subfolder, a file called SearchHelper.dll, which many sites mistakenly identify as malicious (I believe that there is, in fact, a malicious file out there with this name, but this one is from Microsoft and not malicious. Well, not intentionally, anyhow.)
The final solution was also the lamest, something I could have done earlier had I not insisted on doing things the “right way”: I got rid of the folder in question altogether, just manually deleted it. This did the trick, but I do wonder: if for any reason, the folder is restored, would it open up again in the middle of my screen upon the next reboot? And why does Microsoft do this to us anyway?
Between this, obligatory backups, and updates to some half a dozen computers plus some virtual machines, my afternoon and most of my evening was gone.
Meanwhile, my wife received yet another spam e-mail with her own e-mail address used as the sender address. This became a new fad among spammers: why don’t we send spam pretending to be the recipient, perhaps this will trick spam filters? Well, it was time to do something about it, so I did. Unfortunately, these things can get tricky and sendmail’s configuration file, while extremely powerful, is more idiosyncratic than intuitive, with command lines like this:
R$* $| $=R $* $@ OK
So it’s not easy to get it right (that is, filter out unwanted mail but still letting us send out e-mails with our own sender addresses) and I had to be careful not to disable legitimate mail service by accident. Eventually, since it was well past midnight already, I decided that I was too tired to do such delicate surgery, and I only finished it this morning.
Finally, I can now get back to doing something useful on these stupid computers. About bleeping time!
I hold in my hands a copy of the June 5, 1939 issue of Life magazine. It is very interesting.
The cover theme is “America’s future”. On the first page, a full page ad features a Chrysler Plymouth coupe for the princely sum of 645 US dollars, taxes and charges included, delivered in Detroit.
The magazine features an illustrated report about the rescue of submariners from the USS Squalus, an incident famous to this day, as this was the first time sailors were rescued successfully from a disabled submarine nearly 80 meters below the surface.
There is a pictorial report about America’s yesterday, nearly a century of photographs (counting back from 1939 that is!) documenting America’s past.
An elegant Westfield watch cost $9.95, a “sensational new miniature” 35mm camera from Eastman Kodak was advertised at $33.50, while an 8mm Cine-Kodak movie camera (“also makes movies in gorgeous full color on Kodachrome Film!” No mention of sound, mind you) was only $29.50.
There is a full-color, two-page “official map of the United States of America – 1939”, and a wonderful full page color photograph of the Hoover Dam. Then there is a “portrait of America” in maps, pictures, and words. A picture report shows numerous scenes from documentaries about urban life in America. The promise, it seems, is that thanks to the automobile and “smooth new parkways”, Americans will soon live in “towns too small for traffic jams” where children get “a chance to play in safety”. The “girl of tomorrow” wears wire eyelashes and walks about in elevator shoes with 4-inch thick soles.
Then there is “America in 1960”, straight from General Motors’ famed Futurama at the New York World Fair. Express highways with 14-lanes indeed… as if only 14 lanes would suffice in places like Toronto!
In “Headlines to the editors”, we read that “Einstein Believes He’s Found Solution to Gravitation Riddle”. (Not sure what this refers to… perhaps Einstein’s 1939 paper (Ann. of Math 40, 922) challenging the existence of black holes?) We read that “New Key is Found to Atomic Energy […] With Power to Release Largest Store Known on Earth”, and that “Endless Duel of Atoms Declared Source of Fuel in Furnace of Sun”. What the magazine isn’t talking about is that two months later, on August 2, 1939, Einstein would sign a letter that was drafted by Leo Szilard and addressed to President Roosevelt, about the possibility that atomic energy could be used to build a weapon. The rest, the Manhattan Project, that is, is of course history.
Finally, a back page ad suggests, “for smoking pleasure at its best, let up–light up a Camel!” Back in my smoking days, Camels were my favorite.
So what else happened on the week of June 5, 1939? Oh, of course. My Mom was born.
The reason why I am concerning myself with more Maxima examples for relativity is that I am learning some subtle things about Brans-Dicke theory and the Parameterized Post-Newtonian (PPN) formalism.
Brans-Dicke theory is perhaps the simplest modification of general relativity. Instead of the gravitational constant, G, the theory has a scalar field φ, and the theory’s Lagrangian now reads
L = [φR − ω∂μφ∂μφ/φ] / 16π.
Here, R is the curvature scalar and ω is an unspecified constant of the theory.
The resulting field equations are just like Einstein’s, except for two things. First, the field equations for the metric now have additional terms containing derivatives of φ; second, there is a new field equation for the scalar field φ that basically says that the d’Alembertian of φ is proportional to the trace of the stress-energy tensor.
Clever people tell you that Brans-Dicke theory is practically excluded by solar system data, as it would only work for insanely high values of ω. They demonstrate this by building approximate solutions for the theory using the PPN formalism, and find that one of the PPN parameters, γ, will have the value of γ = (1 + ω) / (2 + ω); on the other hand, observations by the Cassini spacecraft restrict γ to |γ − 1| < 2.3 × 10−5, so |ω| must be at least 40,000.
Now here’s the puzzling bit: if you solve Brans-Dicke theory in a vacuum, you find that the celebrated Schwarzschild solution of general relativity still applies: keeping φ constant, you just get back this common solution which is known to fit solar system data well, and which has, most importantly, γ = 1 and the value of ω doesn’t matter.
So which is it? Is it γ = 1 or is it γ = (1 + ω) / (2 + ω)? Something is amiss here.
This dilemma can be resolved once you realize that whereas general relativity has a unique spherically symmetric, static vacuum solution, this is not the case for Brans-Dicke theory. This theory has an infinite family of spherically symmetric, static vacuum solutions. Indeed, I think you could actually use the value of γ to parameterize this solution space. However, once you allow some matter into that vacuum, no matter how little, you are locked in to a specific solution, for which γ = (1 + ω) / (2 + ω). In other words, the only vacuum solution that is consistent with the notion of taking the limit of a matter solution by gradually removing matter is NOT the Schwarzschild solution of general relativity, but another, incompatible solution.
This has extremely important implications for our work on MOG. So far, we have obtained a vacuum solution that appears consistent with observations on scales from the solar system to cosmology. However, a recent paper by Deng et al. challenges this work by suggesting that the MOG PPN parameter γ is not 1 and hence, the theory runs into the same trouble as Brans-Dicke theory in the solar system. Is this true? Did we pick a vacuum solution that happens to be inconsistent with matter solutions? This is what I am trying to investigate.
Some moderately interesting Maxima examples.
First, this is how we can prove that the covariant derivative of the metric vanishes (but only if the metric is symmetric!)
load(itensor); imetric(g); ishow(covdiff(g([],[i,j]),k))$ %,ichr2$ ishow(contract(canform(contract(canform(rename(expand(%)))))))$ ishow(covdiff(g([i,j],[]),k))$ %,ichr2$ ishow(canform(contract(rename(expand(%)))))$ decsym(g,2,0,[sym(all)],[]); decsym(g,0,2,[],[sym(all)]); ishow(covdiff(g([],[i,j]),k))$ %,ichr2$ ishow(contract(canform(contract(canform(rename(expand(%)))))))$ ishow(covdiff(g([i,j],[]),k))$ %,ichr2$ ishow(canform(contract(rename(expand(%)))))$
Next, the equation of motion for a perfect fluid:
load(itensor);
imetric(g);
decsym(g,2,0,[sym(all)],[]);
decsym(g,0,2,[],[sym(all)]);
defcon(v,v,u);
components(u([],[]),1);
components(T([],[i,j]),(rho([],[])+p([],[]))*v([],[i])*v([],[j])
-p([],[])*g([],[i,j]));
ishow(covdiff(T([],[i,j]),i))$
ishow(canform(%))$
ishow(canform(rename(contract(expand(%)))))$
%,ichr2$
canform(%)$
ishow(canform(rename(contract(expand(%)))))$
Finally, the equation of motion in the spherically symmetric, static case:
load(ctensor); load(itensor); K:J([i],[])=covdiff(T([i],[j]),j); E:ic_convert(K); ct_coords:[t,r,u,v]; lg:ident(4); lg[1,1]:B; lg[2,2]:-A; lg[3,3]:-r^2; lg[4,4]:-r^2*sin(u)^2; depends([A,B,T,rho,p],[r]); derivabbrev:true; cmetric(); christof(mcs); J:[0,0,0,0]; ev(E); T:ident(4); T[1,1]:rho; T[2,2]:T[3,3]:T[4,4]:p; J,ev;
These examples are probably not profound enough to include with Maxima, but are useful to remember.
65 years ago today, Allied troops landed in Normandy. CNN described this as “turning the tide”. It didn’t. The tide was turned in the winter of 1941-1942 at Moscow, or later, at Stalingrad. That does not make the sacrifices of those who landed in Normandy on this day any less heroic, mind you, or their accomplishments any less important… not only did they liberate large chunks of Europe from Hitler’s Third Reich, they also ensured that these chunks of Europe would not fall under the boot of Stalin. Sadly, Hungary was not one of these chunks.
In his celebrated speech at Cairo University, Barack Obama’s main message was that we should focus on those things that unite us, not those that divide us. To quote, “It’s easier to start wars than to end them. It’s easier to blame others than to look inward. It’s easier to see what is different about someone than to find the things we share. But we should choose the right path, not just the easy path. There’s one rule that lies at the heart of every religion — that we do unto others as we would have them do unto us.”
Unfortunately, many refuse to listen and instead, pursue their own extremist agendas. And this is not limited to followers of Al-Qaeda or the leaders of Iran. Self-appointed protectors of the West from Jihad also managed to pick apart Obama’s speech, ridiculing every sentence, responding to every request to find that which is common by rejection and calls for hatred.
Fortunately, members of this particular nuthouse no longer run the show in the White House.
Beijing celebrates the 20th anniversary of the Tiananmen Square massacre with umbrellas.
This weirdness came about as plainclothes policemen were trying to interfere with foreign television crews by blocking cameras with open umbrellas:
Umbrellas in Beijing
Whatever reason they have for doing this, it is strikingly pointless. Thanks in part to the tireless efforts of Chinese police, there are no mass demonstrations on Tiananmen Square, no protests, no silent vigils. Journalists who went there would be coming back with boring shots of a square that looks just like it looks on any other day… were it not for the umbrellas.
So why the umbrellas? Why not just round up and haul away foreign journalists? Is this a regime with a (guilty) conscience? When that happened in Hungary, when members of Hungary’s communist Politburo began relabeling the “counterrevolution” of 1956 as a (popular) uprising, the end was not far down the line: within a couple of years, the country opened its borders to East Germans fleeing to the West, transformed itself into a multi-party democracy, and arguably began the chain reaction that led to the collapse of the Soviet empire.
I think we should officially declare June 4 from now on Umbrella Day. (Hey, if we can have a Towel Day…)
AF447 flying from Rio de Janeiro to Paris has not arrived this morning; contact was lost some four hours into the flight, after the airplane flew through what was described by French officials as stormy weather. The last signal from the airplane, if news reports can be believed, was an indication of some electrical fault. A journalist mentioned lightning. At cruising altitude? Yet if it was lightning, I cannot help but be reminded of the fact that the Airbus 330 uses composite materials, carbon composites in particular, extensively; these have a higher electrical resistance than metal, and thus would be heated greatly by a lightning strike; and that experts I heard interviewed over the years said it’s just a matter of time before this will cause a major accident.
It has been 20 years ago this week that Chinese authorities cracked down on the Tiananmen Square protests, killing an unknown number of people.
Arguably, many (most?) Chinese are better off under a regime that produced unprecedented economic prosperity, while providing limited, but not insignificant, civil freedoms. Who knows what would have happened had the protesters succeeded. The record of Eastern Europe is spotty at best; some countries turned into fairly decent democracies, in others ethnic nationalism reared its ugly head, yet elsewhere one dictatorship was just replaced by another.
Yet it’s curious how shy the Chinese are about the events that took place 20 years ago. One can almost see parallels between this and how the events of 1956 were treated in communist Hungary in the 1970s and 1980s. First, it was the “counterrevolution”, that is, if they talked about it at all, which they preferred to avoid. Then, one party official had the courage to stand up and acknowledge that it was an “uprising”, even a “popular uprising”. These words, we now know, marked the beginning of the end for the monolithic one-party system: a dictatorship, no matter how benign or well-intentioned, cannot afford to have a conscience. Is the same thing happening in China?
I’ve been learning a lot about Web development these days: Dojo and Ajax, in particular. It’s incredible what you can do in Javascript nowadays, sophisticated desktop applications running inside a Web browser. I am spending a lot of time building a complex prototype application that has many features associated with desktop programs, including graphics, pop-up dialogs, menus, and more.
I’ve also been learning a lot about the intricacies Brans-Dicke gravity and about the parameterized post-Newtonian (PPN) formalism. Brans-Dicke theory is perhaps the simplest modified gravity theory that there is, and I have to explain to someone why the gravity theory that I spend time working on doesn’t quite behave like Brans-Dicke theory. In the process, I find out things about Brans-Dicke theory that I never knew.
And, I’ve also been doing a fair bit of SCPI programming this month. SCPI is a standardized way for computers to talk to measurement instrumentation, and an old program I wrote used to use a non-standard way… not anymore.
Meanwhile, in all the spare time that I’ve left, I’ve been learning Brook+, a supercomputer programming language based on C… that is because my new test machine is a supercomputer, sort of, with its graphics card that doubles as a numeric vector processor capable in theory of up to a trillion single precision floating point instructions per second… and nearly as many in practice, in the test programs that I threw at it.
I’m also learning a little more about the infamous cosmological constant problem (why is the cosmological constant at least over 50 orders magnitude too small but not exactly zero?) and about quantum gravity.
As I said in the subject… busy days. Much more fun though than following the news. Still, I did catch in the news that Susan Boyle lost in Britains Got Talent… only because an amazing dance group won:
Of all the living heads of state, our Queen (yes, she’s the queen of Canada, too) is perhaps the only one who actually served in World War 2. So why on Earth is she not invited to next month’s 65th anniversary D-day ceremonies? If it’s the French doing it, then perhaps it’s time to rename French fries to, say, Quebec fries?
North Korea today tested two additional missiles. Reason to worry, to be sure.
But there’s absolutely no reason for CTV Ottawa to announce this as “two more nuclear tests”. Not all rockets are nuclear. In fact, as far as I know we have no reason to believe that North Korea is anywhere near mastering the technology to place a nuclear weapon on top of a missile. So please… stop the hype and try to report the actual news, if you would?