Apr 172014
 

If I had to move to a deserted island with only a dozen or so books for the rest of my life, one of them almost certainly would be 100 Years of Solitude, by Nobel prize winning Colombian author Gabriel Garcia Marquez. I first read this book in the 1970s and it’s one of those books that I have re-read from cover to cover, once every decade or so, ever since. It is an absolutely remarkable, unique, wonderful story.

Alas, Gabriel Garcia Marquez is no longer with us. Less than an hour ago, a breaking news e-mail from CNN informed me that he passed away after having been hospitalized for a lung and urinary tract infection. He was 87.

I admit the news brought a tear to my eye.

May he rest in peace, perhaps joining the Buendia family in Macondo. Adios, Gabo.

 Posted by at 5:26 pm
Apr 162014
 

Am I the only one who feels that the way the situation is escalating in Ukraine is eerily reminiscent of 1980s vintage TV movies depicting the events leading up to WW3?

Probably not.

And of course it’s purely symbolic, but I keep reminding myself that this year is the 100th anniversary of the beginning of The War to End All Wars…

 Posted by at 7:00 pm
Apr 102014
 

In light of the latest Internet security scare, the Heartbleed bug, there are again many voices calling for an end to the use of passwords, to be replaced instead by fingerprint scanners or other kinds of biometric identification.

I think it is a horrifyingly, terribly bad idea.

Just to be clear, I am putting aside any concerns about the reliability of biometric identification. They are not as reliable as their advocates would like us to believe, but this is not really the issue. I am assuming that as of today, biometric technologies are absolutely, 100% reliable. Even so, they are still a terrible idea, and here is why.

First, what happens if your biometric identification becomes compromised? However it is acquired, it is still transmitted in the form of a series of bits and bytes, which can be intercepted by an attacker. If this were a password, you could easily change it to thwart an attack. But how do you change your fingerprint? Your retina print? Your voice? Your heartbeat?

Second, what happens if you “lose” your biometric identification marker? Fingers get chopped off in accidents. People lose their eyesight. An emergency tracheotomy may deprive you of your normal voice. What then?

And what about privacy concerns? There have been rulings I understand, in the US and perhaps elsewhere, that imply that the same legal or constitutional guarantees that protect you from being compelled to reveal a password may not apply when it comes to providing a fingerprint, a DNA sample, or other biometric markers.

The bottom line is this: a password associating an account or a service to a unique piece of secret knowledge. This knowledge can be changed, passed on, or revoked, and owners may be protected by law from being compelled to reveal it. Biometric identification fundamentally changes this relationship by associating the account or the service with an unmalleable biometric characteristic of a person.

Please don’t.

 Posted by at 10:27 am
Apr 082014
 

winxp-supportMicrosoft officially ended support for Windows XP today.

I hope someone will sue the hell out of them.

To be clear, I understand why they are doing this: they don’t want to continue supporting forever an obsolete, 14 year old operating system.

But something like one quarter or so of the world’s computers continue running Windows XP. One can argue that Microsoft is not responsible for the behavior of system owners who, for whatever reason, choose not to update their systems. But what about those who do everything right and still become the victims of cyberattacks that utilize networks of unpatched Windows XP computers? The decision to terminate support makes Microsoft a de facto accomplice of these cybercriminals.

My fearless prediction is that within a few months, Microsoft will quietly start releasing high priority security patches for Windows XP again.

Meanwhile, Microsoft began releasing a significant update to Windows 8.1. I noticed that when I updated my Windows 8.1 laptop, it booted directly into the Windows desktop. Wow! Now all we need is a decent Start menu and the ability to perform basic system configuration tasks without going through the touch-optimized “Modern UI” and all will be bliss again. One of these days, I might even upgrade one of my development workstations to Windows 8.1!

 Posted by at 10:21 pm
Apr 082014
 

Quebec-CanadaYesterday, the good citizens of Quebec sent a clear message to the sovereignist Parti Quebecois: they said no to a possible referendum, and no to the divisive politics of the PQ’s proposed “charter of values”.

The day before yesterday, the good citizens of Hungary sent a clear message to the “Viktator”, Hungary’s autocratic Prime Minister Viktor Orban, about his nationalist politics, disastrous “unconventional” economic policies, and systematic abuse of his two-thirds constitutional supermajority to weaken Hungary’s fledgling democratic institutions. “More please,” was the message as voters gave Mr. Orban another strong mandate, possibly another supermajority.

What can I say? Je suis reconnaissant d’être Canadien. Even if my knowledge of French is shamefully limited.

 Posted by at 10:08 pm
Apr 072014
 

Remarkable news from Australia: a U.S. Navy ship* observed an acoustic signal for over two hours that appears to be from two separate “ping” transmitters. This would be consistent with a lost aircraft’s flight data and cockpit voice recorders, both with still operating acoustic transmitters.

This is amazing.

Speaking of pingers, yesterday the ridiculousness on CNN reached new limits. The pingers have batteries that are supposed to last approximately 30 days. The actual duration depends on the age of the battery, its maintenance and storage. And when the battery dies, the process may be a gradual process (i.e., the ping signal weakens but does not necessarily stop immediately.)

None of this prevented CNN from showing a countdown clock, accurate to the second, showing the remaining life of the pinger batteries.

*Actually, a U.S. Navy device towed by an Australian ship.

 Posted by at 12:20 am
Apr 042014
 

A physics meme is circulating on the Interwebs, suggesting that any length shorter than the so-called Planck length makes “no physical sense”.

Which, of course, is pure nonsense.

The Planck length is formed using the three most fundamental constants in physics: the speed of light, \(c = 3\times 10^8~{\rm m}/{\rm s}\); the gravitational constant, \(G = 6.67\times 10^{-11}~{\rm m}^3/{\rm kg}\cdot{\rm s}^2\); and the reduced Planck constant, \(\hbar = h/2\pi = 1.05\times 10^{-34}~{\rm m}^2{\rm kg}/{\rm s}\).

Of these, the speed of light just relates two human-defined units: the unit of length and the unit of time. Nothing prevents us from using units in which \(c = 1\); for instance, we could use the second as our unit of time, and the light-second (\(= 300,000~{\rm km}\)) as our unit of length. In other words, the expression \(c = 300,000,000~{\rm m}/{\rm s}\) is just an instruction to replace every occurrence of the symbol \({\rm s}\) with the quantity \(300,000,000~{\rm m}\).

If we did this in the definition of \(G\), we get a new value: \(G’ = G/c^2 = 7.41\times 10^{-28}~{\rm m}/{\rm kg}\).

Splendid, because this reveals that the gravitational constant is also just a relationship between human-defined units: the unit of length vs. the unit of mass. It allows us to replace every occurrence of the symbol \({\rm kg}\) with the quantity \(7.41\times 10^{-28}~{\rm m}\).

So let’s do this to the reduced Planck constant: \(\hbar’ = \hbar G/c^3 = 2.61\times 10^{-70}~{\rm m}^2\). This is not a relationship between two human-defined units. This is a unit of area. Arguably, a natural unit of area. Taking its square root, we get what is called the Planck length: \(l_P = 1.61\times 10^{-35}~{\rm m}\).

The meme suggests that a distance less than \(l_P\) has no physical meaning.

But then, take two gamma rays, with almost identical energies, differing in wavelength by one Planck length, or about \(10^{-35}~{\rm m}\).

Suppose these gamma rays originate from a spacecraft one astronomical unit (AU), or about \(1.5\times 10^{11}~{\rm m}\) from the Earth.

The wavelength of a modest, \(1~{\rm MeV}\) gamma ray is about \(1.2\times 10^{-12}~{\rm m}\).

The number of full waves that fit in a distance of \(1.5\times 10^{11}~{\rm m}\) is, therefore, is about \(1.25\times 10^{23}\) waves.

A difference of \(10^{-35}~{\rm m}\), or one Planck length, in wavelength adds up to a difference of \(1.25\times 10^{-12}~{\rm m}\) over the \(1~{\rm AU}\) distance, or more than one full wavelength of our gamma ray.

In other words, a difference of less than one Planck length in wavelength between two gamma rays is quite easily measurable in principle.

In practice, of course we’d need stable gamma ray lasers placed on interplanetary spacecraft and a sufficiently sensitive gamma ray interferometer, but nothing in principle prevents us from carrying out such a measurement, and all the energy, distance, and time scales involved are well within accessible limits at present day technology.

And if we used much stronger gamma rays, say at the energy level of the LHC (which is several million times more powerful), a distance of only a few thousand kilometers would be sufficient to detect the interference.

So please don’t tell me that a distance less than one Planck length has no physical meaning.

 Posted by at 11:09 am
Apr 012014
 

I checked my Google AdSense report moments ago, and much to my delight I found that most of my earnings today were due to clicks from Jupiter’s icy moon Europa.

What a nice surprise on the first day of a new month, April.

Wait a moment… First day? April???

 Posted by at 4:20 pm
Apr 012014
 

When the European Organization for Nuclear Research, better known by its French acronym as CERN, presented their finding of the Higgs boson in the summer of 2012, the world was most impressed by their decision to show slides prepared using the whimsical Comic Sans typeface.

Emboldened by their success, CERN today announced that as of April 1, 2014, all official CERN communication channels will switch to use Comic Sans exclusively.

 Posted by at 11:12 am
Mar 302014
 

People or, for that matter, nation states are known by the company they keep.

Here is the list of nations that supported Russia in the recent UN General Assembly vote on the matter of Russia’s occupation of the Crimean peninsula:

  1. Armenia
  2. Belarus
  3. Bolivia
  4. Cuba
  5. North Korea
  6. Nicaragua
  7. Sudan
  8. Syria
  9. Venezuela
  10. Zimbabwe

All leading champions of human rights, freedom and democratic values, I see.

 Posted by at 10:57 am
Mar 272014
 

It was less than 24 hours ago that I wrote about the death of a friend and now I have to do it again: I just learned that Palmer Hanson died a few days ago, after a prolonged illness.

Palmer’s name was well known to the calculator enthusiast community ever since the days of the friendly rivalry between owners of high-end Texas Instruments and Hewlett-Packard calculators in the late 1970s. Palmer was famous, among other things, for writing one of the fastest calendar printing programs for the TI-59 calculator. Though I never met Palmer in person, over the past decade and a half I corresponded with him many times, on account of my Web site dedicated to programmable calculators, rskey.org, and the archival material that I publish there.

It was only a few weeks ago that I received an unexpected parcel from Palmer, with a batch of rare newsletters that he sent to me for scanning and Web publication. I gladly complied. Another batch of newsletters followed shortly thereafter; this batch is still sitting on my desk, as I’ve been busy with work lately and have not had the time to do the scanning.

Therefore, I knew that Palmer was gravely ill, but I was nonetheless hoping that he would stay with us for a little while longer. Unfortunately, when our time comes there is not much we can do, and Palmer’s time came after a long and, I sincerely hope, happy life.

Googling his name just now, I came across a video of a presentation he gave less than two years ago, at HHC2012:

Good-bye, Palmer. I feel privileged to have known you, even if it was just online.

 Posted by at 1:13 pm
Mar 262014
 

25 or so years ago, a mutual friend introduced me to Karoly (Charles) Grandpierre, a struggling Ottawa artist of Hungarian extraction. “Pierre”, as his friends knew him, finished his studies at the Ottawa School of Arts and was trying to make a living as a painter. The friend who introduced us died the following year in a tragic car accident. Although we didn’t really stay in touch, I never completely lost track of Pierre, as there were other mutual friends who from time to time told us about him. That’s how we learned, for instance, that eventually he moved back to Hungary.

Well, Pierre is no more. I just read that he passed away last week, at age 65, after a prolonged battle with cancer.

 Posted by at 3:51 pm
Mar 262014
 

Some details have been released (leaked?) by Inmarsat and the AAIB about their analysis of the flight path of the missing Malaysian airliner. Some details remain frustratingly absent.

Relying on the measured frequency of the signal received from the missing jet, they plotted possible courses of the aircraft and they concluded that only the route that took MH370 to the southern Indian Ocean is consistent with the data. Here are the two critical slides from the annex of their released material:

They are clearly quite confident about the validity of their analysis, and they may be right. Still, there are a few potential issues with which I am not comfortable.

The analysis obviously relies on two key assumptions: first, that the aircraft traveled at a constant speed and second, that its transmitter had good frequency stability. I am not familiar with Inmarsat equipment used on board aircraft, but I do know that a frequency drift of a couple of hundred Hz, over a period of time of several hours and under changing environmental conditions, is not at all unusual [Update (2014/03/28): I now know (thanks, Craig!) that Inmarsat equipment uses an oven-controlled oscillator, with a frequency stability of a few 10 Hz or better over the course of a year, so this is a non-issue] for an oscillator that is running at around 1.6 GHz (which, I believe, is the frequency range used by Inmarsat.)

The analysis also relies on the estimated range at the time of final transmission, which is what was used to generate the infamous “arcs” along which the airplane is expected to be found. Presumably, similar estimated ranges are available for all the intermediate data points. However, this range information was not published in the currently released document. [Update (2014/03/28): Intermediate range arcs were, however, published by the Washington Post on March 21 (thanks again, Craig!).]

It is also unclear to me why the northern route can be excluded, as the top slide shows. If the satellite was stationary with respect to the ground, the northern and southern routes would have identical Doppler signatures. Presumably the difference is due to the fact that the satellite, though geostationary, still moves with respect to the Earth’s surface, e.g., because its orbit is inclined. [Update (2014/03/28): The orbital inclination of the satellite in question is 1.6° (once again, thanks, Craig!)] But this is not explained.

Finally, I am also concerned about the large deviations in the early stages of flight between the predicted and observed values and what it says about the validity of the analysis.

Just to be clear, I do not subscribe to conspiracy theories. I do believe that it may have been premature to exclude the possibility that the aircraft made an emergency landing and remained intact in a remote area not far from the location of its last transponder signal, but I may very well be wrong about this. However, I do think that a little more transparency would be useful.

 Posted by at 8:48 am
Mar 252014
 

These are the dreaded words no pilot wants to see engraved on his or her tombstone: “Controlled flight into terrain”.

Yet this is precisely what happened when a 737 was flying into Resolute Bay, Nunavut in August 2011, only to miss the runway on approach and collide with terrain instead, killing 12 of the 15 souls on board.

The reasons are aptly summarized in this brief video from the Transportation Safety Board of Canada.

The sad story of this flight reminds me of something I first learned when I was 17 or so, working on my first ever paying software development contract, for Hungary’s equivalent of TSB Canada. I was taught that it is rare, almost unheard of, for an air accident to have a single cause. Most of the time, accidents happen as a result of a chain of mistakes, and if only one link in the chain is missing, the accident would not occur. In this case, the links of the chain included an inadvertent autopilot setting; a compass alignment issue; bad visibility; and breakdown in communications between the two pilots on board. At any time before the final few seconds, the situation was still salvageable, if only the pilots became aware of what was happening. But by the time the ground proximity warning alarm sounded, it was too late.

 Posted by at 8:21 pm
Mar 232014
 

For the past week or so, CNN has been blabbering about the presumed fact that the pilots of the vanished flight, MH370, programmed a new route into the flight computer at some time between 1:07 and 1:19 AM.

This was, even according to one of their own experts, blatant nonsense. Wherever this information came from, it did not jive with the known facts. Namely that the ACARS system in board would not transmit a yet-to-be-executed flight plan to the ground even if they subscribed to the transmission of navigational data (which they didn’t.) And that the ACARS system on board was not scheduled to make another transmission until 1:37 AM, at which time it was no longer functional.

It became kind of obvious from sporadic comments that this “fact” was nothing but speculation, based on the presumed smooth turn the aircraft executed shortly after the last voice transmission; someone must have concluded that such a smooth turn was done by the flight computer, and thus it had to be entered into the flight computer, presumably after the last (1:07 AM) ACARS transmission.

None of this made any sense to me, and today, CNN confirmed my suspicions: Malaysian authorities assert that no air-to-ground transmission indicated a route change.

In response to this, CNN quickly presented the straight facts. Or they tried, anyway:

But… exactly where did they get the idea from that the last transmission showed normal routing all the way to Beijing? According to their own words, what Malaysian authorities said was that the last transmission did not show a preprogrammed turn. From this, you cannot conclude anything as to what it did show, especially given the fact, reported earlier, that the airline’s ACARS subscription did not cover navigational data in the first place.

Exactly what would it take for CNN to present the facts correctly, just once, without adding their own bits of creative fiction?

Update (2014/03/23): It appears that CNN is blameless at this point. The piece of creative fiction (if that’s what it is) apparently comes directly from Malaysia’s transportation ministry. That does not make it more believable, though, in my opinion.

 Posted by at 3:35 pm
Mar 222014
 

I looked out my window this morning, and this is what I saw:

I keep thinking that this is how Ice Ages start: spring arrives later and later, winter arrives sooner and sooner, until one year, there is no summer… the snow never completely melts. The next year, more snow arrives and soon (in a few decades) there is a glacial layer of compacted ice that will eventually thicken to a depth of a kilometer or more. And then, it’s here to stay for the next hundred thousand years or so.

No, I don’t expect an Ice Age to arrive on our doorstep just yet, but maybe this view explains why Canadians appear less concerned than they should be about global warming.

 Posted by at 9:17 am
Mar 182014
 

So the big announcement was made yesterday: r = 0.2. The inflationary Big Bang scenario is seemingly confirmed.

If confirmed, this discovery is of enormous significance. (Of course, extraordinary claims require extraordinary evidence.)

So here is the thing. In gravity, just as in electromagnetism, outside of a spherically symmetric body, the field will be indistinguishable from that of a point source. So for instance, if the Earth were a perfect sphere, simply by looking at the orbit of the Moon, you could not possible tell if the Earth was tiny and superdense, or large and less dense… only that its total mass is roughly six quadrillion kilograms.

A consequence of this is that if a spherically symmetric body expands and contracts, its (electrical or gravitational) field does not change. In other words, there is no such thing as monopole radiation.

In the case of electromagnetism, we can separate positive and negative charges. Crudely speaking, this is what a transmitting antenna does… and as a result, it produces dipole radiation. However, there is no such thing as negative mass: hence, there is no such thing is dipole gravitational radiation.

The next thing happens when you take a spherically symmetric body and squeeze it in one direction while allowing it to expand in the other. When you do this, the (electric or gravitational) field of the body will change. These changes will propagate in the form of quadrupole radiation. This is the simplest form of gravitational waves that there is. This method of generating radiation is very inefficient… which is one of the reasons why gravitational waves are both hard to produce and hard to detect.

To date, nobody detected gravitational waves directly. However, we did detect changes in the orbital periods of binary pulsars (superdense stars orbiting each other in very tight orbits) that is consistent with the loss of kinetic energy due to gravitational radiation.

Gravitational radiation was also produced when the Universe was very young, very dense, expanding rapidly. One particular theory of the early expansion is the inflationary theory, which suggests that very early, for a short time the Universe underwent extremely rapid expansion. This may explain things such as why the observable Universe is as homogeneous, as “flat” as it appears to be. This extremely rapid expansion would have produced strong gravitational waves.

Our best picture of the early Universe comes from our observations of the cosmic microwave background: leftover light from when the Universe was about 380,000 years old. This light, which we see in the form of microwave radiation, is extremely smooth, extremely uniform. Nonetheless, its tiny bumps already tell us a great deal about the early Universe, most notably how structures that later became planets and stars and galaxies began to form.

This microwave radiation, like all forms of electromagnetic radiation including light, can be polarized. Normally, you would expect the polarization to be random, a picture kind of like this one:

However, the early Universe already had areas that were slightly denser than the rest (these areas were the nuclei around which galaxies later formed.) Near such a region, the polarization is expected to line up preferably in the direction of the excess density, perhaps a little like this picture:

This is called the scalar mode or E-mode.

Gravitational waves can also cause the polarization of microwaves to line up, but somewhat differently, introducing a twist if you wish. This so-called tensor mode or B-mode pattern will look more like this:

We naturally expect to see B-modes as a result of the early expansion. We expect to see an excess of B-modes if the early expansion was governed by inflation.

And this is exactly what the BICEP2 experiment claims to have found. The excess is characterized by the tensor-to-scalar ratio, r = 0.2, and they claim it is a strong, five-sigma result.

Two questions were raised immediately concerning the validity of this result. First, why was this not detected earlier by the Planck satellite? Well, according to the paper and the associated FAQ, Planck only observed B-modes indirectly (inferred from temperature fluctuation measurements) and in any case, the tension between the two results is not that significant:

running_rvsnsThe other concern is that they seem to show an excess at higher multipole moments. This may be noise, a statistical fluke, or an indication of an unmodeled systematic that, if present, may degrade or even wipe out the claimed five sigma result:

speccomp

The team obviously believes that their result is robust and will withstand scrutiny. Indeed, they were so happy with the result that they decided to pay a visit to Andrei Linde, one of the founding fathers, if you wish, of inflationary cosmology:

 What can I say? I hope there will be no reason for Linde’s genuine joy to turn into disappointment.

As to the result itself… apparent confirmation of a prediction of the inflationary scenario means that physical cosmology has reached the point where it can make testable predictions about the Universe when its age, as measured from the Big Bang, was less than one one hundredth of a quintillionth of a second. That is just mind-bogglingly insane.

 Posted by at 10:08 am
Mar 162014
 

Is history thumbing its nose at us? The parallels between the events unfolding between Russia and Ukraine today vs. Germany and Czechoslovakia in the 1930s are unmistakable.

No, I am not going to evoke the hyperbole, comparing Putin to Hitler. (I’ll leave it to Russian propagandists to talk about “fascists” taking over Ukraine.)

But the actual events are another matter.

Consider the parallels between the 1936 Berlin olympics and Sochi.

The parallels between the Third Reich’s prosecution of homosexuals and Russia’s.

The parallels between the Crimea and the Sudetenland.

The parallels between German cries of outrage about the maltreatment of ethnic Germans abroad, and Russia’s.

The parallels between a post WWI Germany, destined to be a Great Power but humiliated by defeat and a vindictive peace treaty, and Russia, destined to be a superpower but humiliated by the collapse of its Soviet empire and encroachment by NATO, Russia’s former arch-enemy.

The analogy is not perfect. Nonetheless we better smarten up before it’s too late. Ironically, the “war to end all wars” started exactly 100 years ago this year… and far from being a deliberate war, it broke out as a result of a series of deadly miscalculations, which in the end caused the deaths of tens of millions, the end of an unprecedented half century of prosperity, the collapse of the existing world order, and guaranteed instability and upheaval (not to mention another, even more devastating World War) in the coming decades.

I spent the first 50+ years of my life in peace and prosperity. I want to live out the rest of my (hopefully long) natural life the same way, not become a civilian casualty of a war more devastating than anything in history.

 Posted by at 6:41 pm