James Lovelock – Unlocked!

James Lovelock

James Lovelock is a true genius: an original, maverick, and influential 94 year-old British scientist, he is most famous for his Gaia hypothesis, which views the Earth as a self-regulating, single organism. When the theory was first propounded in the early 1970s, it was largely ignored by the scientific community.  I think this may have been due to the connotations of the name Lovelock chose; Lovelock himself said that naming his theory after a Greek goddess resulted in his ideas being picked up and championed by many non-scientists.  The Gaia Hypothesis appealed to hippies, freethinkers and environmentalists, and many people in search of alternative life-styles chose to latch on to his ideas, interpreting them as a kind of neo-Pagan religion.  I have nothing against hippies, greens and alternative life styles:  it just seems a shame that for a long time the Gaia Theory was associated with some whacky ideas which led to it being labelled as ‘unscientific', and attracting ridicule from other leading scientists and thinkers including Richard Dawkins.

The hypothesis  suggests that the Earth and its natural cycles can be thought of like a living organism. When one natural cycle starts to go out of balance other cycles work to bring it back, continually optimising the conditions for life on Earth. The theory helps to explain some of the more unusual features of planet Earth, such as as why the atmosphere isn't mostly carbon dioxide, and why the oceans aren't more salty.

The Gaia Hypothesis was based on Lovelock's own ideas and observations, but was originally lacking a thorough scientific explanation. Times change however, and these days it is a different story. By the time of the second Chapman Conference on the Gaia Hypothesis, held at Valencia, Spain, in June 2000, concerns about environmental and ecological issues looming large, Lovelock's ideas were being taken more seriously, and there was a huge interest in the developing science of Bio-geophysiology.   

The Earth seen from Apollo 17

Think about it: Hurricane Katrina, Tsunamis, the Fukushima Disaster, flooding in the UK, droughts, the melting of the Polar ice-caps, El Nino, the mudslide in Washington State. Global warming, climate change, rises in ocean levels and the increasing frequency of terrifying extreme weather events in recent years mean that there is now an urgent need to seriously, scientifically and holistically address issues of climate change, environmental destruction and global pollution. We have all been forced to think more deeply about our home planet and how human intervention is affecting the global environment. Gaia Hypothesis and its holistic approach to thinking about the Earth is now being taken extremely seriously and is used in subjects such as geophysiology, Earth system science, biogeochemistry, systems ecology, and climate science.

Lovelock’s huge contribution to science has been widely recognised and rewarded. As well as  being created Companion of Honour and Commander of the Order of the British Empire, he became a Fellow of the Royal Society in 1974 and in 2006 the Geological Society of London awarded Lovelock its highest honour, the Wollaston Medal, largely for his work on the Gaia theory.

Dig Deeper

You can learn more about Lovelock and his pioneering ideas at the Science Museum in London.  This year (April 2014 – April 2015) they are staging an exhibition about him. Among the highlights of the exhibition, called Unlocking Lovelock,  are his laboratory notebooks, drafts of his papers and equipment from the laboratory in his back garden, where some of his most important work was done. The exhibition also features tools used by Lovelock to build many of his inventions, including a watchmaker’s lathe and the home-made gas chromatography equipment that journeyed to the Antarctic and back and proved crucial to scientists’ current understanding of global atmospheric pollution.

http://www.sciencemuseum.org.uk/visitmuseum/Plan_your_visit/exhibitions/lovelock

Books About Gaia by James Lovelock

1979     Gaia: A New Look at Life on Earth

1988    The Ages of Gaia: A Biography of Our Living Earth

1991     Gaia: The Practical Science of Planetary Medicine,

2000     Homage to Gaia : The Life of an Independent Scientist (Independent Voices)

2006    Medicine for an Ailing Planet

2007    The Revenge of Gaia

2010    The Vanishing Face of Gaia: a Final Warning            

2014    A Rough Ride to the Future                                                     

The Mobius Strip

If you have never heard of it before this mathematical curiosity will blow your mind.To be quite honest though, maybe it only blew MY mind because of my lamentable lack of spatial awareness.  Being a typical girl, I cannot parallel park and I cannot turn a cartwheel.  (Though now in my 50s I am a rather elderly girl and have pretty much given up on that one).  I must also admit that, as a student, I was no mathematical genius.  Always more of a words than a numbers person, I only managed to scrape a reasonable GCSE grade thanks to the unbelievable patience and remedial efforts of my lovely maths teacher Miss Williams. Nearly 40 years ago she had the dubious honour of trying to instill a basic grasp of the rudiments of arithmetic, algebra, and geometry into my thick skull, and she is still receiving therapy for that today. That poor woman deserves a medal. 

Mobius Strip with Ants, by Escher

Nonetheless, although I am no mathematician, I can safely say I am a true Geek. That is to say, I am curious about the world around me and take a keen interest in all sorts of subjects, whether or not I am any good at them. I was reminded of this intriguing phenomenon just last week when the cold English winter drove me out to the shops to look for a cosy winter scarf, and I found one in the form of a Mobius Strip. The paradox of the Mobius Strip made a big impression on me when I first learned about it, and I hope you will find it interesting too. 

Sometimes also known as the Mobius band, the Mobius Strip was discovered in 1858 by August Ferdinand Möbius and also (coincidentally and independently) by Johann Benedict Listing, both German mathematicians. Like many of the best ideas, the basic concept is simple, and childishly easy to demonstrate.  By the way, for anyone with young kids, this is a good way to get them interested in mathematics.  It’s never too early to start training a Geek!

All you need to do this is some paper and glue or sticky tape.  Start by making a long paper strip: it doesn’t particularly matter how long or how wide you make it, but say 5 cm wide by 30 cm long, for example.  Now take your glue or a bit of sticky tape. You are going to stick the two ends together, but before you do that, just put a half-twist in the band of paper, et voila!  You have a Mobius strip. 

By introducing that simple half-twist you will find that your two-sided strip of paper has now miraculously become a single-sided strip.  It is no longer possible to take two coloured pencils and colour the strip differently on either side. Don’t believe me?  Just try it. Now you have made your Mobius strip, you can start playing.  

Some Mobius Strip Experiments

First, try taking a pen and drawing a line along one side of the paper, and see what happens.  You will find that you cover the entire surface of the strip, over what used to be both sides of your paper.  This proves that it has now become a continuous one-sided band.

Now take a pair of scissors and cut along the middle of your Mobius strip     lengthways, along the line you have just drawn.  You will find that is stays in one piece, twice as long as the original.

Draw a new line on your strip, about a third along its width.  Once again, you will find the line eventually joins up to the point you started from.

Now cut along your newly drawn line. What do you think is going to happen?  I bet you didn’t guess that you would end up with two linked loops!

Mobius Strips in Literature

If you enjoy reading classic American authors and humorists like Mark Twain, Damon Runyon and Bill Bryson you should check out William Hazlett Upson.  Back in the 1940s and 1950s  he wrote a series of short stories for the Saturday Evening Post newspaper about Alexander Botts, a salesman for the Earthworm Tractor Company.  In A Botts and the Mobius Strip the eponymous hero thwarts his boss by restitching a factory conveyor belt into the form of a Mobius Strip, thus preventing the outside of the belt from being painted a different colour from the inside. TBH, I have not actually read this yet.  I got as far as visiting the Amazon store, and found a copy of the Alexander Botts Earthwork Tractors collection priced at £1,539.65.  I was naively hoping for a free download for my Kindle, but no such luck! 

Moving to the world of Sci-Fi, in The Wall of Darkness by Arthur C Clarke, the universe is re-imagined as a Mobius Strip, and in A Subway Named Mobius by AJ Deutsch the Boston underground network becomes so huge and complex that  the system starts to behave according to some mysterious mathematical principles, causing trains to disappear.  Also worthy of mention in this context are John Barth’s Lost in the Funhouse, Vladimir Nabokov's The Gift, and the movie Donnie Darko.

Finally, a Mobius Strip Joke

Why did the chicken cross the Mobius Strip? To get to the same side, of course.

FootNote: Some Related phenomena for you to Google and introduce in your geeky maths lessons:-

Cross cap

Strange Loop

Klein bottle

Paradox

The Fall and Rise of Alan Turing

He was a mathematical genius and computer science pioneer, but also a gay British man back in the days when homosexuality was against the law.  Tragically, publicly humiliated after a criminal conviction, and suffering from deep depression, he committed suicide on June 7, 1954 at the age of 41. On that day one of the most brilliant minds of the twentieth century, a patriot who had played a key role in defeating the Nazis and saving thousands of lives in the Second World War, was lost forever.

Alan Turing

Who was he?  To be honest, twenty years ago I would probably not have heard of him myself, but today he is one of my heroes.  In case you have been living on a desert island for the last ten years, perhaps I should mention that I am talking about Alan Turing, Englishman, a mathematics professor, a World War II code-breaker, and a pioneer of computer science. 

In the 1930s Turing worked at Cambridge University in the UK and at Princeton University in the US. At this time he developed the idea for a proto-computer known as a Turing Machine, a hypothetical device not intended for practical use, but which was key to helping computer scientists understand the possibilities of mechanical computation.

Enigma

 His knowledge and love of mathematics led to a fascination with cryptography, and he was recruited to work part-time for the British Secret Service at the Government Code and Cypher School. During the war he became a key member of staff at the top-secret Bletchley Park establishment, and led the team that in 1939 developed the code-breaking electro-mechanical machine known as Bombe. 

The Bombe Code-Breaker

This invention gave the British government an enormous advantage over Germany and the Axis relatively early on in the war. The German military establishment was using an ingenious machine called Enigma to encrypt their military communication. 

So confident were they that the Enigma Code could not be broken, they used it for all sorts of communications on the battlefield, at sea, in the sky and, significantly, within their secret services.   In fact, thanks to Turing’s Bombe, the British were able to read and understand these vital messages; an advantage which is thought to have shortened hostilities by years, and saved may lives.

He later played a vital role in the development of Colossus, the world’s first large-scale electronic digital computer, which was designed by engineer Tommy Flower, and also used by the Bletchley Park code-breakers.

Bletchley Park and the Official Secrets Act

The British Official Secrets Act meant the Alan Turing and Bletchley Park story was kept under wraps until many years later. At the end of the war, much of the Bombe and Colossus equipment and their blueprints was destroyed on Winston Churchill’s orders. It was only in the 1970s that its work was finally made public.  In fact, during the Second World War, Bletchley Park, near Milton Keynes in Buckinghamshire, was the site of the United Kingdom's main decryption establishment.

The people who worked there all signed the Official Secrets Act, swearing never to talk about the site and the sensitive intelligence activities which were planned there, and most of them took the secret to the grave.  At the time, to most of the staff it was simply known as ‘BP’, although the Wrens (Women's Royal Naval Service personnel) stationed there referred to it as HMS Pembroke V.  These days Bletchley Park has been turned into a museum, but one of its cover names, Government Communications Headquarters, still lives on in the present-day British intelligence centre GCHQ at Cheltenham.

The Post-War Era

In the years following the war Turing's security clearance was withdrawn: homosexuals were considered a bad security risk as they were vulnerable to blackmail, so he could no longer work for British Intelligence. Eventually, in 1952, he was arrested and tried for homosexuality, then a criminal offence. To avoid prison, he submitted to a year-long regime of oestrogen injections, a process popularly known as ‘chemical castration’, which was intended to neutralise his libido.

Then the tide began to turn.  Social attitudes changed over time, gradually becoming more liberal.   The law against homosexual acts in the UK was repealed in 1967 by The Sexual Offences Act.   Late in 2013 Alan Turing received an official royal pardon.  That is fine as far as it goes, but since homosexuality is no longer an offence, why should he be pardoned?  Surely it would be far more appropriate if Alan Turing’s family, friends and supporters could find it in their hearts to pardon the British government for unjustly criminalising him in the first place!  

Sir Alan Turing?

I know, I know, the ‘royal pardon’ is a legal formality, and maybe it does have a value in publicly ‘wiping the slate clean’.  I am only happy that we now live in a more open and enlightened society where people are not marginalised, hounded and barred from fully participating in society due to their colour, creed, gender or sexual orientation.  That’s the theory, anyway.

Now, not content with the pardon alone, many of Alan Turing’s admirers and supporters are now campaigning for him to be given a posthumous knighthood. Many years ago I worked as an Analyst Programmer, and Alan Turing is the most inspiring role model I can think of for anyone working in IT. Since 1966, the Turing Award has been given annually by the Association for Computing Machinery for technical or theoretical contributions to the computing community. It is widely considered to be the computing world's highest honour, equivalent to the Nobel Prize. I am very proud to include him here in my roll-call of honorary Geeks.

Footnote:-

Benedict Cumberbatch will play the role of Alan Turing in a forthcoming bio-pic called The Imitation Game, directed by Morten Tyldum with screenplay by Graham Moore, due to be released in 2014.

A Brief History of Time, Communication, The Cloud and Everything

In the beginning there was a cloud. Slowly, over aeons of time, bits of this huge cloud clumped together and consolidated. Then suddenly one day - bang! It  got hot enough to trigger a nuclear reaction. The sun appeared and blew away most of the cloud.  Some bits of cloud remained, and these turned into the planets. After a bit of violent upheaval, they finally settled down into the configuration we have today, with the Earth situated at a very pleasant distance from the sun and at a nice moderate temperature. Under these conditions it was inevitable that life formed and eventually evolved into animals, plants and the human race.

 

In the Beginning There Was a Cloud

If you look at the literature on the history of the human race, it is obvious that human beings and their ancestors never actually communicated at all for the first two and a half million years. That's rather a long time to just sit and stare at your neighbour. No wonder they developed stone axes and decided to hit each other with them. They must have been absolutely fed up with the sight of each other.

Eventually however, someone came up with the bright idea that it might be nice to talk, so language came into being. This seems to have happened somewhere around 50,000 years ago, and it was an instant hit. It was like a virus, with everybody now chattering away to everybody else.  The Earth, totally silent for the previous 4.5 billion years after it coalesced out of the primordial cloud, suddenly became a noisy place.  It was full of conversations like  "I heard Mrs Ugg talking to the Oggs the other day.  Terrible people, those Oggs, their cave is always filthy, full of old dinosaur bones. I wouldn't deign to speak to them myself".  But other people would speak to them, and they continued to do so for millennia.

Stories were invented so that people could pass them on and others could learn from what had happened before.  These stories turned into lengthy sagas, and the amount to remember became huge. As time went on, the sagas turned into entire encyclopedias, and it all started to get a bit difficult. Eventually everybody got fed up. This stimulated the human brain to suddenly cross another size threshold, and to invent WRITING. What a day that was!  The only problem was this: what on earth to write on?

They tried a few things. Sand: no problem writing, but the words tended to get obliterated quite quickly.  Rock: could scratch this a bit, but it was hard work to get any amount of information down. Then somebody thought about animal skins. This seemed to be fine with just two minor problems. The animals objected rather a lot to being skinned, so the ones chosen tended to be the smaller ones.  This meant that you either had to write very small or stitch a lot of them together. The other problem was that these started to smell after a few days and then rotted shortly afterwards, once again defeating the object of the exercise.

The human brain must have hit another huge technological breakthrough  about 7,000 years ago, when somebody thought it would be a good idea to go and pick a few reeds and stick them together, strip off the outside and use the sticky bit in the middle. Bash it all together with a hammer, making an even stickier mess, and  finally weight it all down and  leave to dry. So papyrus was born, and the Egyptians loved it. At this point it seems that the capacity of the human brain started to know no bounds, and in no time at all (c 2,000 years), paper was invented. This could be written on with ease, didn't disintegrate, and it could be copied again and again. What's more, it could be put together to make books. Libraries soon came into being, holding all the wisdom of human history.  There was a minor blip when the library of Alexandria went up in flames taking about three quarters of the world's knowledge with it, but it didn't take long to go and work it all out again.

In the 19th Century a man called Babbage invented something called a 'Difference Engine', the world’s first computer. At first computer data were saved on paper, but this method required a lot of trees, took up masses of storage space, and nobody ever got round to reading it anyway. So somebody invented paper tape.  Not a great advance, as this was even more difficult to read than print-out, but you could at least feed it back in to your computer.  After that came reel-to-reel tapes. Marvellous! Now you could retrieve any information you wanted; you just had to remember which tape it was on, and hope that the machine operators weren't on a coffee break.

Finally we move into the 21st Century, and somebody has invented a way of storing data in a cloud. Just look up above you and you can see what a great advance this is.  In the UK there is certainly plenty of storage space. This is the future! Unlimited on-line document storage, right up there in the sky. Your plans are safely stored in a nice big cloud hanging over Manchester.  No danger of ever losing that data: there is always a cloud over Manchester.

There are more clouds on Earth than anybody can possibly use, but if we do ever run out of them, just look up a little higher into the heavens.  Venus is covered in them, and Jupiter, with a surface area over 120 times that of Earth, has an inexhaustible supply. Is there another technological advance beyond Cloud Computing? Maybe so, but it isn't needed just yet. There is plenty of cloud space to store all the world's knowledge for many hundreds of years to come. So we can all live happily ever after, safe in the knowledge that it is all secure, accessible, and constantly backed up.

The Hidden Power of the Algorithm

What is an Algorithm?

To start with the basics, let’s look at a definition of an algorithm.  I like this one from Whatis.com?

An algorithm (pronounced AL-go-rith-um) is a procedure or formula for solving a problem. The word derives from the name of the mathematician, Mohammed ibn-Musa al-Khwarizmi, who was part of the royal court in Baghdad and who lived from about 780 to 850. Al-Khwarizmi's work is the likely source for the word algebra as well.

A computer program can be viewed as an elaborate algorithm. In mathematics and computer science, an algorithm usually means a small procedure that solves a recurrent problem.

Another way of looking at it is to say an algorithm is a series of logically ordered instructions, rather like a recipe for baking a cake.  If you are sensible, and use a Delia Smith recipe, you will probably end up with a beautiful cake.  If you are foolish enough to go to a Keith Floyd recipe book, it will probably turn out to be a culinary disaster.

A Mathematical Genius at Work

In itself, an algorithm is neither good nor evil.  As a problem-solving tool it could be effectual or it could be useless; it all depends on the quality of the human mind that creates and programmes the algorithm in the first place it, and the appropriateness of the human response to the algorithm results.

The War on Terror

Thanks to revelations reported in The Guardian by ex American intelligence analyst Edward Snowden, data-gathering techniques by government security organisations have been hitting the headlines across the globe. The US intelligence organisation known as the National Security Agency or NSA has been widely reported to be covertly collecting colossal quantities of data from our phones, computers, and social networks.  Thanks to advances in communications techniques and the ease and cheapness of current-day data storage, it is now physically and economically feasible for them to create, maintain and interrogate these mammoth databases as they search for terrorist conspiracy activities.

The other reason for the existence of these data monsters is that modern computing techniques make it feasible to trawl through them.  It would not be possible for human beings to read all of that information (and it would no doubt be an incredibly boring task, too), but algorithms can search it, analyse it and report back to the government security agencies. These techniques are a major weapon in the state’s armoury for the so-called war against terrorism.  We know that algorithms are deployed by the NSA and GCHQ (the UK equivalent listening centre, General Communications HQ at Cheltenham), but we can only take an educated guess at the rules used by the algorithms, and hope that they are being used wisely.

Big Brother is Watching You

Algorithmic techniques have also been used in recent years to facilitate ‘predictive policing’ and in some instances they have achieved dramatic successes.  The idea here is to harness the power of the algorithm to provide data to enable police to deploy their resources in the right place at the right time.  This is sometimes known as ‘Minority Report Policing’, after the Steven Spielberg  sci-fi movie with Tom Cruise, where "PreCrime", a specialized police department, stops crime before it actually happens, using information provided by three psychics called "precogs". 

In the real world the technique is more correctly known as CRUSH, or ‘Criminal Reduction Utilising Statistical History".  The earliest example of this I could find was ‘Operation Blue Crush’, a pilot Crush operation staged in Memphis, Tennessee back in 2005, and during which 1,200 people were arrested over the course of just three days.  Have a look at this link to find out more: http://www.memphispolice.org/blue%20crush.htm

Algorithms, Quants, and the City

As a reader of this blog you are already well aware of the power of  The Geek.  Did you know that, in the city, highly-paid geeks known as ‘Quants’, or Quantitative Analysts, are employed to create algorithms to formulate trading strategy?  The traditional picture of the stock market trading floor peopled by traders in suits and ties making frantic telephone calls and yelling ‘Sell, sell!’ has now largely been superseded by computer servers running ‘algos’ to predict market fluctuations.

Most financial institutions, including banks and pension funds, now rely on algorithms. Sometimes competing algorithms have been known to clash, and, on occasion they have been blamed for speeding up trading to the extent of destabilizing the market and causing a meltdown.  It’s not only the big rollers in the city that can be affected: the ‘algo’ is also impacting ordinary people by influencing the way their savings and pension funds are invested.

Algorithms in Everyday Life

It doesn’t stop there. The power of the algorithm extends way beyond the rarefied world of investment and trading. Think about dating websites, credit checks, online retailing, retailer loyalty schemes, tailored and targeted discount  vouchers, online insurance quotations and internet search engines: they all use the same principles to analyse our personal interests and our buying habits.

Algorithms are being used extensively now simply because of the explosion in the quantity, quality, and availability of data spawned by the era of global mass communications.  The technique is now so widespread and industrialised that it is commonly known as ‘Data Mining’.

All this is nothing new, of course.  Alan Turing and his team of Bletchley Park code-breakers used algorithms to powerful effect back in the 1940s, and they were instrumental in victory against the Nazis in World War II.  This is a perfect example of an algorithmic tool being harnessed to good effect.  In the wrong hands, and wielded unwisely, there is also the potential for it to become an instrument of the powerful and unscrupulous who seek to dictate, repress, control and censor.

The Mystery of the Antikythera Mechanism

This is an intriguing story I first heard a few weeks ago, when my boss Steve, a keen amateur astronomer and general all-round geek in his own right, suggested that the Antikythera Mechanism would make a good subject for a blog posting.  I have kept the story in reserve since then, until a couple of nights ago, when BBC 4 broadcast a documentary programme about it, The Two-thousand-Year-Old Computer, which reawakened my interest. Researching a little further,  I found that some pretty exotic and exaggerated claims have been made about the Antikythera Mechanism, including

• It is the oldest known analogue computer
• It was made by aliens
• It can predict the future
• It proves the existence of time travel

Heady stuff indeed, and much too fascinating to be left on the back-burner any longer, so here it is.

The Antikythera Wreck Site

The story began in the Mediterranean back in 1901, when a sudden and violent storm forced sponge divers to make an unscheduled stop near the island of Antikythera, on the edge of the Aegean between mainland Greece and Crete.  Whilst stranded there they decided they may as well try a dive, and discovered not sponges, but a 2000 year-old Roman shipwreck.  The first impression was of human corpses and dead horses scattered across the sea-bed.  Closer inspection revealed them to be the remains of a cargo of priceless antiquities including some rare and exquisite bronze statures, most of which are now housed in the National Archaeological Museum in Athens.

A Fragment of the Antikythera Device

Among the hoard of beautiful art works, which included such treasures as The Philosopher’s Head, and  full-size statues of Hercules, The Ephebe, a discus thrower, a marble bull and a bronze lyre, another, less prepossessing  artefact was found.  Broken into 82 pieces and badly corroded by its long sojourn at the bottom of the sea, the Antikythera Mechanism looked like a piece of old junk.  It clearly was some kind of antique machine, however, and an initial archaeological study carried out in 1902 revealed a gear wheel embedded inside.  This led historians to believe the object to be an astrolabe or astronomical clock:  its true purpose and significance was not discovered for another hundred years.

The main problem for scholars has always been the sheer depth and inaccessibility of the wreck site.  The sponge divers who discovered the wreck back in 1901 were only able to venture down so far thanks to their heavy diving suits, with their bulky copper and brass helmets and weighted shoes.  Even with this equipment (which remained the standard diving kit from the late 19th Century through most of the 20th Century) one of the divers died trying to salvage the wreck, and two others were paralysed by the bends.

By the 1970s, the story had moved on and, after decades of careful conservation and cleaning and in-depth study, the mystery of the Antikythera Mechanism began to unravel. Modern techniques such as X-ray and gamma scanning allowed scholars to shed more light on its internal workings, revealing a more complex system of gearing than was previously recognised.

In 1974 Derek de Solla Price of Yale University published the results of years of intensive research, demonstrating that the device was constructed along mathematical principles for astronomical purposes.  For example, it would probably have been used to calculate the position of the Sun and Moon, the phases of the Moon, eclipse cycles, and the locations of the planets.

Professor de Solla and his Reproduction of the Device

Professor de Solla discovered that it was probably made as early as 87 BC, and although no other similar devices from that period have ever come to light, the sophistication of the design led him to believe that it cannot have been the first one of its type. Such is the complexity of the design that it is commonly referred to as the first analogue computer.  A reproduction of the mechanism created by Professor de Solla, along with other reconstructions  created by other scholars, is currently on display in the Athens Museum in a special exhibition about the Antikythera shipwreck.

By the 1970s deep-sea the design of deep sea diving equipment had also been modernised and improved, allowing famous TV personality and undersea explorer Jacques Cousteau to visit the Antikythera wreck.  A few more minor finds were brought up by Cousteau’s team, but, even with their sophisticated scuba equipment, they could only spend limited time on the sea bed.  For many years afterwards, nobody visited it at all, but in the last couple of years there has been fresh interest in studying the mechanism, and permission is being sought from the Greek government to send some new expeditions to the site.

So, the mystery of the Antikythera Mechanism continues to baffle and intrigue. Who knows, there may be other undiscovered fragments still down there. There may even be another mechanism down there!

Postscript

The Antikythera Mechanism was the inspiration for and a central plot device in a  2010 TV film called  Stonehenge Apocalypse, in which it saves the world from an impending catastrophe.

The Invisibility Man Wins Prestigious Scientific Award

As a self-confessed and hopeless geek, I am, of course, obsessed with the incomparable Sir Isaac Newton. If you have visited this blog before you may have read about Isaac Newton and the Cat Flap, a tongue-in-cheek but nonetheless respectful homage to the great man. I was therefore extremely interested to hear about the recent award of the Institute of Physics’ prestigious Newton medal to Professor Sir John Pendry.   This award is made annually for outstanding contributions to physics, and Sir John has won it for  pioneering  the concept of the 'invisibility cloak' and developing a new class of 'metamaterials'.

The human race has always been fascinated by the idea of invisibility, and our literature  is full of it. Probably the first and most interesting instance occurred in 1897 in HG Wells' science fiction novella (or, as Wells styles it, ‘grotesque romance’) The Invisible Man.  In this story Griffin, the anti-hero, stumbles upon an invisibility formula during his time as a medical student, and uses his invisibility to commit crimes.

Other famous invisibility plot devices occur in Star Trek, in which the Starship Enterprise protects itself from attack by means of a ‘cloaking device’ using technology stolen by Captain Kirk from a Romulan ship, and Harry Potter, where the ‘invisibility cloak’ is a magical garment which renders the wearer invisible. For all those of you who would not classify Star Trek and Harry Potter as literature, I can only apologise for mentioning them in the same breath as the great HG Wells, who is another one of my personal heroes.

In the 21st Century real scientific knowledge is starting to catch up with the predictions of science fiction. How close is current scientific knowledge to achieving true invisibility?   In HG Wells' story, invisibility was achieved chemically, with the use of 'special pigments'. Nevertheless his ideas are uncannily similar to Sir John Pendrys’s metamaterial discoveries. In chapter 19 of The Invisible Man, CERTAIN FIRST PRINCIPLES, Wells offers this scientific explanation:

 But consider, visibility depends on the action of the visible bodies on light. Either a body absorbs light, or it reflects or refracts it, or does all these things. If it neither reflects nor refracts nor absorbs light, it cannot of itself be visible. You see an opaque red box, for instance, because the colour absorbs some of the light and reflects the rest, all the red part of the light, to you. If it did not absorb any particular part of the light, but reflected it all, then it would be a shining white box. Silver! A diamond box would neither absorb much of the light nor reflect much from the general surface, but just here and there where the surfaces were favourable the light would be reflected and refracted, so that you would get a brilliant appearance of flashing reflections and translucencies—a sort of skeleton of light. A glass box would not be so brilliant, nor so clearly visible, as a diamond box, because there would be less refraction and reflection. See that? From certain points of view you would see quite clearly through it. Some kinds of glass would be more visible than others, a box of flint glass would be brighter than a box of ordinary window glass. A box of very thin common glass would be hard to see in a bad light, because it would absorb hardly any light and refract and reflect very little. And if you put a sheet of common white glass in water, still more if you put it in some denser liquid than water, it would vanish almost altogether, because light passing from water to glass is only slightly refracted or reflected or indeed affected in any way. It is almost as invisible as a jet of coal gas or hydrogen is in air. And for precisely the same reason!

Compare this with Sir John’s proposal for creating an ‘invisibility cloak’ by using metamaterials.  These are substances defined not by their chemical constitution, but by their internal structures on the smallest scale, which allow them to guide light around objects and render them invisible to the human eye. Altering the nano-scale structure of a metamaterial causes directional changes in its electromagnetic waves.  Light waves flow around objects covered in metamaterial and – hey presto – they are invisible!

I must admit that I am only a geek with no real scientific credentials, and I apologise for the inadequacy of my technical explanation. For a fuller explanation of the properties of metamaterials, why not have a look at Professor Pendry’s website? http://www.cmth.ph.ic.ac.uk/photonics/Newphotonics/

More about the Newton Medal   

This year's Newton award will be presented at a ceremony in London on November 15.  Professor Pendry will give the Institute's Newton Lecture in October. Previous winners of the Newton medal include Martin Rees, Leo Kadanoff, Edward Witten, Alan Guth and Anton Zeilinger.

From the website of the Institute of Physics:

http://www.iop.org/about/awards/newton/page_60376.html