Celebrating Isaac Newton's birthday

Which world changing person’s birth have you been celebrating today? On Christmas Day 1642 Isaac Newton was born. His work laid much of the foundation for our modern understanding of the universe by uncovering the force that keeps it together, and showing it’s the same as what makes an apple fall. He formulated what are known as Newton’s three Laws of Motion. He may have been the greatest scientist ever.

To divert you from the day’s excesses may I tempt you to Deborah Byrd’s Earth Sky blog where you'll find links to the laws of motion as well as Newton’s revelations about gravity.

But the most extraordinary revelation about Newton is this: that according to some, science wasn’t the biggest thing in his life. What was even more important to him was biblical textual criticism, in which he excelled, and his unitarian belief (no trinity) which he had to keep to himself, for fear of being expelled from Cambridge University.  A couple of years ago I attend a fascinating lecture on this.

An apology the world will little note nor long remember

Something I missed recently, but I'll include it here in case you missed it too:  coinciding with the 150th anniversary of the Gettysburg Address on 19th November, a retraction of an 1863 newspaper editorial dismissing the speech as “silly remarks”.

“We pass over the silly remarks of the President. For the credit of the nation we are willing that the veil of oblivion shall be dropped over them and that they shall be no more repeated or thought of.” With these stinging words did the Patriot & Union of Harrisburg, Pennsylvania achieve infamy in the annals of journalism, by panning the presidential speech that lives as one of the most treasured orations in the English language.

Three weeks ago, the successor paper Patriot-News revisited this unkind judgement, suggesting that their predecessors were perhaps under the influence of partisanship, or of strong drink - whilst wittily observing that “the world will little note nor long remember” the paper's apology.

This is all good fun, but ahistorical, of which more below.

Lincoln at Gettysburg (unknown date)

First, here's the full text of the Gettysburg address. [1]

Four score and seven years ago our fathers brought forth on this continent, a new nation, conceived in Liberty, and dedicated to the proposition that all men are created equal.

Now we are engaged in a great civil war, testing whether that nation, or any nation so conceived and so dedicated, can long endure. We are met on a great battle-field of that war. We have come to dedicate a portion of that field, as a final resting place for those who here gave their lives that that nation might live. It is altogether fitting and proper that we should do this.

But, in a larger sense, we can not dedicate - we can not consecrate - we can not hallow - this ground. The brave men, living and dead, who struggled here, have consecrated it, far above our poor power to add or detract. The world will little note, nor long remember what we say here, but it can never forget what they did here. It is for us the living, rather, to be dedicated here to the unfinished work which they who fought here have thus far so nobly advanced. It is rather for us to be here dedicated to the great task remaining before us - that from these honored dead we take increased devotion to that cause for which they gave the last full measure of devotion - that we here highly resolve that these dead shall not have died in vain - that this nation, under God, shall have a new birth of freedom - and that government of the people, by the people, for the people, shall not perish from the earth.

Now to the question of how the Patriot & Union came to overlook history being made that day. It's worth reading “Living on the wrong side of history? The Harrisburg Patriot & Union's notorious 'review' of the Gettysburg Address”  from Patriot-News website.

This deals with the issue historically, and discounts the playful suggestion that their 1863 predecessors were under the influence of strong drink. In the first place, the newspaper's own reporter described the President's speech in Gettysburg like this: "The President then arose and delivered the dedicatory address, which was brief and calculated to arouse deep feeling."  But the crux is that the Patriot & Union supported the Democratic party, and was hostile to Lincoln, his conduct of the war, and his war aims. Moreover, the paper’s editors had been in put in jail for sedition a year before. So there was stuff going on.

As a final thought, I've often wondered if Lincoln really believed that the world would little note, nor long remember, what he said that day.  He well knew he had crafted a masterpiece … surely he entertained the hope that the world would recognise this?

[1] This is the text most often reproduced. There are others, see Abraham Lincoln Online.

Of logarithms, fraudsters and exoplanets

Pristine log tables. Well-thumbed would be better.

Suppose you need to multiply 263.4 by 351.2 you would nowadays use a calculator, but when I was at school in the 1960’s we used logarithms.  Logs to their friends.  In a book of log tables we would look up the log of 263.4 and the log of 361.2, add the two logs together, then look up the result in an antilog table, and bobs your uncle. Not as quick as a calculator but easier than multiplying.  We each carried around a well-thumbed book of log tables, yet one thing we all failed to notice was that the pages for numbers beginning with 1 were more well-thumbed than pages for numbers beginning with 9.  Or if we noticed we never asked ourselves why. But a character called Newcomb did, in 1881. For he it was that discovered Benford’s law and in the process proved Stigler’s law (Stigler’s law being that in science, laws are always named after the second person to discover them; and in this case the second person to discover the law was Benford.) 

Benford's law states that in most lists of data, the first digits of the numbers follow a pattern of probability, where 1 is the commonest first digit, and 9 the least common.  Take for example a list giving the heights of the tallest buildings. Almost one third of the buildings in the list will have a height whose leading digit is 1. Next most frequent in the leading position is the digit 2. And so on, till you come to 9 which is likely to be found as the leading digit in only 4.6 per cent of buildings.

Or rivers. Look at Wikipedia’s list of world rivers longer than 1000 km. You'll find a table giving length in km, length in miles, drainage area in km², and average discharge in m³/s. At my rough count, it contains five hundred numbers, of which only 18 start with a 9.

Fraudsters

Benford's law also applies to financial data, a fact unknown to most fraudsters, who tend to suppose that the best way to insert phoney entries into a list of expenses or transactions, is to make up numbers at random, with as many starting with 9 as starting with 1. But Benford’s law soon finds them out. And the spooky thing is, it matters not whether the transactions are in pounds, euros or dollars.

Exoplanet with two suns and an exomoon. But is it real?

I've read the Wikipedia article on Benford’s law which purports to explain why this should be so,  and I can't follow it as it involves high level maths.  But no matter, all this is by way of working out how many exoplanets have been discovered.

I recently mentioned that the Kepler mission found over two thousand planets orbiting other stars. Now it's important to note that these haven't actually been seen in the usual sense of the word. They have been seen in strings of data, indicating very slight periodic dimmings in the brightness of a star. From this data scientists have inferred size of a planet, distance from the star, and other factors.

But inferences can be wrong. In some cases the data could perhaps result from another phenomenon entirely, and have nothing to do with a planet at all.

And according to this week’s New Scientist, that’s where Benford’s law comes in. 

Thomas Hair at Florida Gulf Coast University wondered if Benford's law would hold true even beyond the solar system, and examined data from an online catalogue that lists 755 confirmed exoplanets and nearly 3500 planet candidates. Planet masses are given in multiples of Earth's or Jupiter's mass. He found that whichever of these two units is used, the figures closely fit Benford's law, making it highly likely the supposed planets really are out there. "The close fit with Benford's law gives a confirmation to experts' belief that most of the candidates are valid," he says. 

I wish I still had my log tables so I could check that well-thumbed business for myself. I looked in vain on the web for an image of a used copy to put at the top of this post. For fun, I've spent the last half hour reminding myself how to use logs. If you too last used them in the 1960’s take a look.

Of Little Red Riding Hood and horses' hooves

Horse's rear hoof.
It evolved from the middle toe.

Evolution has supplied horses with limbs modified for running,  as well as a special feature for locking their knees allowing them to stand for long periods, and a hoof which evolved from an extruded middle toe.  These features enabled the horse to survive on open grassland by successfully fleeing from predators.   Now here's the crux. All this is equally true of a hoofed South America mammal called a litoptern, which went extinct between two and five million years ago, and is unrelated to the horse. It too, lived on open grassland and in order to successfully flee from predators evolved those very same features, even including that middle toe which evolved into a hoof. This I learnt some years ago at a lecture about convergent evolution.  The point being that evolution, when confronting similar challenges, has an uncanny knack of arriving at similar solutions, even at widely separated times and places.

Which brings me to folk tales about wolves.

“The Wolf and the Kids" is a tale popular throughout Europe and the Middle East. A nanny goat warns her kids not to open the door while she is out in the fields, but is overheard by a wolf. When she leaves, the wolf impersonates her and tricks the kids into letting it in, whereupon it devours them. Versions of this tale occur in collections of Aesop's fables, in which a goat kid avoids being eaten by heeding the mother's instruction not to open the door, or seeks further proof of the wolf's identity before turning him away.

The tale may be new to you, but you doubtless know by heart the tale of Little Red Riding Hood. She sets out for her grandmother’s house with a basket of goodies, but a big bad wolf finds out about her itinerary, gobbles up grandma and disguises itself to lure the little girl to her doom. "What big teeth you have!" Little Red Riding Hood remarks before the wolf devours her.

 Little Red Riding Hood at the
door to Grandma's house.
Late 19th century trade card.

Lets look at the parallel between the two stories.  In each we have a wolf who gets dinner by impersonation – of the nanny goat in the first story, and of the grandma in the second.  “The Wolf and the Kids" probably originated in the 1st century AD. “Little Red Riding Hood” arose about a thousand years later. Durham University anthropologist Dr Jamshid Tehrani borrows evolutionary analysis from biology to study similarities among folktales, and claims to show that “Little Red Riding Hood” is descended from “The Wolf and the Kids”. Moreover, “Little Red Riding Hood” evolved from this root once in Europe, and again, quite independently, in Africa.  So, like the horse’s hoof, Little Red Riding Hood has it seems evolved twice.  Dr Tehrani himself draws the parallel with convergent evolution: “The fact that Little Red Riding Hood 'evolved twice' from the same starting point suggests it holds a powerful appeal that attracts our imaginations” he says. 

His article appeared in the open access journal PLOS ONE. If you can follow it all, you're a better man than I am, but luckily there’s a press release, and a very readable account from NBC News.

The best-known version of Little Red Riding Hood was published by the Brothers Grimm 200 years ago, based on a 17th-century story by the Frenchman Charles Perrault who distilled it from oral retellings in France, Austria and northern Italy.  You'll find both on the University of Pittsburgh site along with six other related stories,  which folklorists group together and classify as tales of type 333 in the Aarne-Thompson-Uther system.

Dr Tehrani traces the ancestry and development of Little Red Riding Hood by observing features such as: is the victim single or a group of siblings, goat or human, eaten in their own home or a relative’s.  I found out a bit about classifying folktales when I researched the story of King Midas and his asses ears, a couple of years ago.

That's all I want to say about wolves, but I should have told you more about the lecture on convergent evolution.  One of the first I ever attended in Cork, in December 2005, it was by the Cambridge Professor Simon Conway Morris and his talk explored the heretical suggestion that  evolution has a destination, or even a destiny.  He had recently published his book Life’s Solution – Inevitable Humans in a Lonely Universe,  and argued that in the light of what we know about convergent evolution we should expect intelligent extraterrestrial life, if we ever come across it, to be strikingly similar to ourselves.
 

Are we poised for a jaw dropping discovery?

In my bones I feel that searching for extra-terrestrial intelligence is slightly loopy. Yet many leading scientists, especially at the SETI Institute, engage in the search and sustain their hopes that a sign of intelligent life will one day manifest itself. Radio signals are the usual target, but the lights of alien cities have also been canvassed.

The foregoing is only a digression, since I really wanted to talk about the prospects of finding any sort of life in the universe. An editorial in last week’s New Scientist suggested that if life is common in the universe, we will have found signs of it by the middle of the next decade, “a truly jaw-dropping discovery”.

This prediction of finding signs of life within 12 years or so is based on the NASA Kepler spacecraft’s hunt for habitable exoplanets. These are defined as rocky planets, roughly Earth-sized, orbiting other stars in the habitable zone where water is likely to be liquid.  For three years (finishing last May when the camera malfunctioned) Kepler surveyed a tiny patch of the Milky Way. Even though using an inefficient detection method, it found over two thousand planets, a handful of which seem Earth-like. 

Optimists, extrapolating these results to the whole sky, say it looks certain that our galaxy is home to billions of Earthlike planets.  There are pessimists though. One posted a comment to the New Scientist website claiming Kepler has not found a single earth size planet in the habitable zone.

Paul Davies: life on earth
may have been a fluke

Kepler's successor, the Transiting Exoplanet Survey Satellite, is due to launch in 2017. It's being designed to search for the most promising exoplanet targets for next-generation studies. Restricting its search to nearby stars, it will scour the sky for small rocky worlds, and is expected to find hundreds. Future instruments such as the James Webb Space Telescope and the proposed StarShade mission will follow up these discoveries, probing the planets' atmospheres for signs of life. For example, to an alien astronomer, the oxygen, ozone and methane in Earth’s atmosphere would be a giveaway, because these gases are unstable, so their abundance here would indicate their being continually replenished by life.  So these gases, if present in an exoplanet’s atmosphere, would be an indicator of life as we know it; whilst certain other unstable gases could, by the same logic, be evidence of weird life.

A few comments about New Scientist’s expectation of a truly jaw-dropping discovery. First, notice their caveat “if life is common in the universe”. Many argue that life is probably very rare in the universe. If so, most (perhaps all) of those billions of Earthlike planets could be completely sterile.

Paul Davies (a guru of mine) is fond of saying that fifty years ago scientists used to say life was very unlikely; and now the fashion is to say it's very likely … yet nothing has changed: we're just as ignorant now about what causes life to arise as ever we were.  Here's a review of his 2010 book The Eerie Silence.

Next, if scientists succeed in analyzing a planet’s atmosphere and conclude “wow, life!” they won't, from that data alone, be able to tell intelligent life from microbes. But no matter, to me that would be jaw dropping enough.  Of course you can be sure that the SETI radio antennae will immediately be trained on any such planet. That may be loopy but it has to be done. 

The banality of evil

From a photographic exhibition depicting Nazi terror during my Berlin visit a couple of weeks ago  [1]. There were atrocity photos too, but the image that spooked me most was this ... …

The caption was : SS female auxiliaries (“SS Maids”) and SS men from Auschwitz concentration camp at the SS retreat Sola-Hütte 30 kilometers south of the camp in an idyllic mountain landscape, undated (probably July 22, 1944). At center is Karl Höcker, adjutant to camp commandant Richard Baer.

I look at the date, July 1944, and I ask myself: didn't these people see that in less than a year the war would be lost and they would be called to account?  Well they weren't of course so maybe that’s not such a good question, but what would they say in later years when their children saw this photo? “I was just doing my job, it seemed important at the time”, I suppose. The banality of evil [2].

The American museum director who now curates this and similar photographs says they “vividly illustrate the contented world they enjoyed while overseeing a world of unimaginable suffering. They offer an important perspective on the psychology of those perpetrating genocide."

I see from Der Spiegel's website that the SS female auxiliaries photo came from an album belonging to Karl Höcker, who took the pictures as personal keepsakes. Prior to its liberation by the Allies, Höcker fled Auschwitz, and after the war worked for years in a bank, unrecognized. In 1963 he went to trial, claimed he “had no possibility in any way to influence the events”, was sentenced to seven years in prison, and was released after serving five. He died at the age of 88 in 2000.

The next photo is a bit fuzzy I'm afraid. It's just a snap I took as I went round the exhibition, and I haven't been able to find a better copy on the web.

The caption here is : SA men publicly humiliate Hermann Weidemann, a local council member from the SPD who had been taken into “protective custody”. Hofgeismar, May 2, 1933. Sitting on an ox with a cardboard sign hung round his neck, Weidemann was led through Hofgeismar by the SA in a pillory procession. The victim, a Social Democrat councillor in the town, was followed by a crowd of curious spectators.

I think that in mentioning the curious spectators the caption has it about right. There seems to be a party atmosphere. What would the two girls in the foreground tell their children 20 years later if this photo came to light? “I didn't understand politics, I was too young” …  “My parents told me the Social Democrats were destroying Germany and had lost us the war in 1918, something had to be done” … “It seemed like a carnival, I didn't really know what was going on” …  “Back then Hitler seemed to have the right idea but in the end he took it too far” … "Is that me? I'm ashamed ... " ?? 

By the way I see from Wikipedia that from 1933 and 1944 Weidemann was held in Sachsenhausen concentration camp, and for three years after the war, from 28 April 1945 to 1948, he was mayor of Hofgeismar, whose streets the Nazis had paraded him through on the ox (though the Wikipedia article fails to mention this event).

I'll close with my most disappointing Berlin photo. Hitler’s bunker. I imagined a conducted tour showing the bedrooms, the kitchen, Hitler’s office, the garage full of staff cars, all as in the 2004 film Downfall (if you haven't seen it you must). But it was not to be. This picture of me looking glum in a car park is as good as it got.

It seems that after the war the Soviets levelled the Chancellery buildings; though despite some attempts at demolition the underground complex remained largely undisturbed until the two halves of the city were reunited in 1989. During reconstruction of that area of Berlin, those sections of the old bunker complex that were excavated were for the most part destroyed. The site remained unmarked until 2006, when a small tourist information board was put up.  Some of the corridors of the bunker still exist today, but are sealed off from the public.  I wonder why this cavalier attitude to an important piece of archaeology?  To prevent it becoming a neo-Nazi shrine perhaps?

[1] At the Topography of Terror – the present-day name for the site on which the most important institutions of the Nazi apparatus of terror and persecution were located between 1933 and 1945. The buildings are all gone, replaced by a modern exhibition hall.

[2] Banality of evil : the idea that evil occurs when ordinary individuals are put into corrupt situations that encourage their conformity. The phrase was coined by philosopher Hannah Arendt after witnessing the 1962 trial of high-ranking Nazi Adolf Eichmann who seemed, at least to Arendt, to be the most mundane of individuals whose evil acts were driven by the requirements of the state and orders from above.
`

I visit Berlin and puzzle

Just back from Berlin where I couldn’t resist posing at the local metro station under a sign indicating the exit for Karl Marx Alley (boulevard really), Peace Street and The Street of the Paris Commune. Or what about the inscription on the back wall of this regrettably dark photo of the main staircase of Humboldt University:

Die Philosophen haben die Welt
nur verschieden interpretiert,
es kommt aber darauf an,
sie zu verändern

Not even attributed, you're meant to know it's from Marx's Theses on Feuerbach. Cool.  “The philosophers have only interpreted the world, in various ways. The point, however, is to change it.”

The building [1] stands on Bebelplatz, at the right of this panoramic view:-

On 10 May 1933, Bebelplatz made history in an inglorious manner. It was the site of the most notorious of the book burnings organized by the Nazis, in which important works of world literature were thrown into the flames.  Karl Marx's Theses on Feuerbach first amongst them no doubt. The 20,000 volumes burnt included Heinrich and Thomas Mann, Erich Kästner, Stefan Zweig, Heinrich Heine, and Kurt Tucholsky. Don't worry I haven’t heard of some of them either but you get the idea.  A monument to this outrage has been created in the square, consisting of a glass panel opening onto a white underground room with empty shelf space for (supposedly) all 20,000 volumes. A plaque bears an epigraph from an 1820 work by Heinrich Heine: Das war ein Vorspiel nur, dort wo man Bücher verbrennt, verbrennt man am Ende auch Menschen (That was only a prelude; where they burn books, they end burning people).

I say supposedly because my rough estimate of the shelf space was 6,000 volumes. My friend Vincent got a slightly higher figure but nowhere near 20,000. 

The books all came from the university building with the Karl Marx inscription. Though the inscription wasn’t there then of course. And we are told the ignorant thugs who did this deed were mainly “students”. I feel sorry for the librarian. I visualise him being charged with the duty of identifying all the offending volumes, which doubtless included many rare first editions. My sympathy might be misplaced of course, maybe he was a Nazi and revelled in the work. But I imagine not. A rector with Nazi tendencies, Eugen Fischer, was appointed in 1933 but I haven’t discovered if he was yet in place at the time of the book burning.

I want to comment on all those old buildings you see in the panoramic view of the square. They are, from the left, the State Opera, St. Hedwig's Cathedral straight ahead and the Humboldt University building. Now I haven't found an image of Bebelplatz in 1945 but here’s a fairly typical image of Berlin in that year.

So what I puzzle over is, when I was in an old church, the Humboldt University, various 19th century museum buildings, what was I actually in? A repaired pre-war building? Or a modern replica?  On a four day visit to Berlin I encountered a fair mix of modern buildings and old ones, but how old were the old ones really? 18th and 19th century? Or 1960’s? I came away without a feel for the answer to this question.  I've plenty more to say about Berlin but I'll stop here for now.

[1] Now known so far as I can tell as the old law library