Friday, January 30, 2015

'The 'Imitation Game': A Shoo-In To Win "Best Picture" (Some Minor Spoilers)

The Imitation Game poster.jpg
Do you own a computer? Do you work with one in any kind of capacity? Then, it is incumbent on you to see  the Weinstein Company's  'The Imitation Game', starring Benedict Cumberbatch, Keira Knightly and Charles Dance (from the 'Game of Thrones'). This film had us gripping our seats for two hours as we watched the goings on at an obscure place called Bletchley Park, during World War II . According to Wikipedia:

"Bletchley Park, in Milton Keynes, Buckinghamshire, was the central site of the United Kingdom's Government Code and Cypher School (GC&CS), which during the Second World War regularly penetrated the secret communications of the Axis Powers – most importantly the German Enigma and Lorenz ciphers."

But left unsaid is the torturous, years long effort to crack the Enigma machine's ciphers which daily set new U-Boat and bombing targets and which the British were at a loss to stop using archaic methods. None of the usual cipher-busting methods work because well, you were talking about a machine that could create over 170  million permutations of the letters. At a dead end, the War Office had no choice except to try a new approach, and that is where Alan Turing (played by Cumberbatch) enters. Turing, then a Mathematics professor, told the war authorities: "The only thing that can beat a machine is another machine, and that is what I intend to build." And that led to the original "Turing Machine" and the basis for modern digital computers.

Turing and his team (including Keira Knightly's character) then set out to crack ENIGMA, though at the beginning Turing is isolated - all by himself in a side room - fiddling with his rotors and circuits, lacking the social skills to entice cooperation. Indeed, the other four members of his team (before Knightly arrives) continue their old ciphering methods and regard Alan's machine as a more or less useless waste of time, even costing lives every day.

To test the success of ongoing efforts, the Bletchley team had its own German ENIGMA machine (seized during one op)  so that if they believe at any point they've cracked the code for the day - they can run it through the German  machine to see if the result matches actual events, e.g. U-Boat attacks. Once recruited for their task, they aim  -each day - to crack the ENIGMA code to be able to stave off attacks the next day.

None of this works, and ultimately the War Office loses patience, threatening to close down  the Cipher squad unless they can get results in one month. They're already miffed at having shelled out over 100,000 pounds for Turing's  machine.

I will not relate the critical breakthrough, but in many ways the "Eureka" moment - captured when Turing is hobnobbing at a party (after finally developing some rudimentary social skills) - reminded me of John Nash's solution of his game theory breakthrough  in a key scene in 'A Beautiful Mind' . That occurred while in a Princeton, NJ bar with his buddies,  trying to decide which of 4 coeds they'd approach.

At Bletchley, the solution was now in sight,, which amounted to an input.  As the team raced back to check it they're delighted by the success. The ENIGMA machine spit out actual latitudes and longitudes for future U-Boat attacks with the dates. Some members of the team demand an immediate phone call to alert commanders of when and where the attacks will occur, but Turing won't have it. "You can't do that!" he screams. One team member with a brother on a ship due to be attacked is so vexed he punches him in the face.

The reason? If the Germans see that the attacks are neutralized, they will know the ENIGMA code has been cracked and therefore  re-design new codes and new machines.  The only solution? The Cipher bunch comes up with a new program in conjunction with the War Office called "Ultra".  The basis of Ultra is - having seen which attacks are coming up - to compute statistically (using the Poisson distribution of 'expected events') the accepted number of  interventions (hence saved lives) which are below the random threshold - so as not to arouse suspicion.

In the last part of the film we see the team at work computing 'saves' that are acceptable and within the bounds of the "randomly expected"  statistics.  It is brutal, thousands still die, but it is vastly more important to preserve the cracked existing code to ensure the D-Day success.

Of course, this Bletchley Park plot  runs in parallel with Turing's own life situation and being hounded by a nosey detective - determined to open his high security war file. When the snoop meets impediments he gets suspicious and ultimately his  persistence pays off. It is at this point, Turing's homosexuality is exposed and he's given the brutal choice of either spending his years in prison - or taking hormone treatments which remove the sex drive (but also wreak havoc on one's brain.)

To my mind this is the best movie of the year, and I would be amazed if it didn't win the Academy's "Best Picture". See the movie and then decide whether you agree!

To read more about ENIGMA and Enigma machines:

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