Archive for June, 2012

Was Alan Turing’s death an accident?

Posted in Uncategorized on June 23, 2012 by quantummoxie

On the 100th anniversary of the birth of Alan Turing, a new analysis of the evidence surrounding his death by Prof. Jack Copeland, suggests that it may actually have been accidental and not a suicide by cyanide poisoning as the official inquest had ruled.  Prof. Copeland points to Turing’s penchant for experimentation that once resulted in his receiving several severe electrical shocks.  At the time of his death, he was electrolyzing solutions of cyanide and electroplating spoons with gold, a process that requires potassium cyanide.  The experiment was actually wired into the ceiling light socket (yikes!).  At any rate, Copeland’s arguments are based entirely on the evidence and the evidence actually suggests an accident and not suicide.  It should be noted that both his mother and brother apparently had always felt that the death was accidental (see Hodges’ biography for more, though Hodges himself has suggested the accident scenario was a ruse created by Turing to spare his mother the pain and humiliation).

This, of course, does not excuse the absolutely horrific treatment he had received in the time leading up to his death over his homosexuality.  In fact, he had agreed, a year prior to his death, to chemical castration in an effort to “curb” his homosexual tendencies.  Personally, I find this ironic (not to mention repugnant) given the long history of homosexuality in Britain’s public boarding schools (notably at Eton).  The one problem I have with a lot of commentary on Turing is that it tends to be fairly standard practice to bemoan the injustice of his treatment while noting his extraordinary contributions to mathematics, computer science, and the British war effort, as if those were the reasons he should have been treated differently.  The way in which Alan Turing was treated was reprehensible regardless of who he was.

For example, consider this statement by Lord McNally when denying the petition to posthumously pardon him earlier this year:

A posthumous pardon was not considered appropriate as Alan Turing was properly convicted of what at the time was a criminal offence. He would have known that his offence was against the law and that he would be prosecuted. It is tragic that Alan Turing was convicted of an offence which now seems both cruel and absurd—particularly poignant given his outstanding contribution to the war effort. However, the law at the time required a prosecution and, as such, long-standing policy has been to accept that such convictions took place and, rather than trying to alter the historical context and to put right what cannot be put right, ensure instead that we never again return to those times.

The emphasis is mine.  Even now, in 2012, his conviction is viewed in the light of his contributions.  But, then, that is the type of society we live in and, in some ways, have always lived in.  People who are wealthy, famous, powerful, or otherwise stand out from the crowd, apparently deserve better treatment than the rest of humanity (and that doesn’t make me a socialist, by the way – true capitalism doesn’t play favorites).  In 2009, then-PM Gordon Brown apologized for the government’s treatment of Turing.  But, as gay rights activist Peter Tatchell pointed out that nearly 100,000 British men received similar treatment and that “[s]ingling out Turing just because he is famous is wrong.”

There is quite a bit that we can learn from Alan Turing’s life and death, both scientifically and socially.  One can only hope that we pay attention to the latter in addition to the former.

The Venus Transit in multiple wavelengths

Posted in Uncategorized on June 6, 2012 by quantummoxie

I missed the very beginning of the transit of Venus last evening, most notably the first and second contacts, due to my daughter’s dance recital.  But immediately afterward, the sun poked its nose out and we raced to a pre-determined meeting spot for my local club (ASNNE).  Everyone was taking down their scopes by the time we arrived since the sun had gone behind the trees across the street, but we were streaming it indoors and some of my friends managed to get some pretty cool shots.

Instead, we headed home and I found the absolutely outstanding feed provided by The Exploratorium who had a telescope set up at around 11,000 ft. on Mauna Loa in Hawaii.  It was far better than the feeds that provided nothing but endless chatter and very little in the way of actual views.  The Exploratorium’s stream moved between three different filters – hydrogen-alpha, calcium (I don’t know if it was the H or the K line) and white – and moved around a bit so as to pick up views of some of the sunspots, prominences, and flares (quantum phenomena at work!).  Commentary was intelligent but not overly technical (so my kids could understand it) and only lasted a few minutes every half-hour.  Plus, in the 20-25 minutes between commentary they streamed spontaneously composed (likely by computer) ambient music in surround sound.  So I hooked up my computer to my home theatre system and we watched for a couple of hours on the wide screen with ambient music surrounding us!  It was rather Floydian, I must say…

At any rate, I stayed up late to catch the end and was able to witness some really interesting things.  In particular, take a look at the image I created below using a partial screen capture (I’m not sure about the rights to these images since they came from The Exploratorium’s telescope via the Internet, but as I’m using them in an ostensibly educational manner, I am hoping they will forgive me!):

Notice that “third contact” (the point at which Venus’ disk reaches the edge of the Sun’s disk after crossing the latter) occurs in white light before it does in H-alpha.  This is because, in a sense, the hydrogen-alpha filter allows us to look “deeper” into the atmosphere.  Or, rather, there are portions of the Sun’s atmosphere that are not visible in the white light filter image.  In fact, third contact in H-alpha didn’t occur for another few minutes (this is a tad bit later than third contact in H-alpha, but close):

Looking deeper still (and about 30 seconds earlier) into the atmosphere, here is roughly third contact in calcium:

What’s interesting is that the contact points in the transits of 1761, 1769, 1874, and 1882 were used to calculate the astronomical unit based on a suggestion made in 1663 by future St. Andrews University (my alma mater) professor James Gregory.  If any of these data values were undertaken using different filters (which they were not, since nothing of the kind existed then), a different value for the AU (or perhaps just a greater uncertainty, depending on how the data was taken) would have been reached.  Keep in mind that when Lalande calculated the value of 153 million kilometers (±1 million kilometers) in 1771, the precision was apparently less than what had been hoped.  When Newcomb calculated the value of 149.59 million kilometers (±0.31 million kilometers) after the 1882 transit, this approximately 2% increase in precision was enough to nail down the value (and thus eliminate the need for parallax calculations).

Now, I seriously doubt there is a 2% difference between the H-alpha and the white light third contact points.  Nevertheless, the difference might have a measurable effect on the calculation of the AU.  Of course, these days we use more sophisticated techniques to measure the AU that don’t rely on a transit.  But it is nevertheless interesting to think about.

Incidentally, there were also a number of huge sunspots (larger than Earth) and a prominence on the lower portion that was bigger than the disk of Venus which means it was way bigger than Venus in actuality.  In fact it was likely larger than Neptune.

All in all, an amazing, once-in-lifetime (actually twice, since they come in pairs separated by eight years) event!