Month: December 2014

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Quantum Immortality

Commuting days until retirement: 91

A theme underlying some of my recent posts has been what (if anything) happens to us when we die. I’d like to draw this together with some other thoughts from eight months ago, when I was gazing at the roof of Exeter Cathedral and musing on the possibility of multiple universes. This seemingly wild idea, beloved of fantasy and science fiction authors, is now increasingly taken seriously in the physics departments of universities as a serious model of reality. The idea of quantum immortality (explained below) is a link between these topics, and it was a book by the American physicist Max Tegmark, The Mathematical Universe*, that got me thinking about it.

Max Tegmark

Max Tegmark

I won’t spend time looking at the theory of multiple universes – or the Multiverse – at any length. I did explain briefly in my earlier post how the notion originally arose from quantum physics, and if you have an appetite for more detail there’s plenty in Wikipedia. There are a number of theoretical considerations which lead to the notion of a multiple universe: Tegmark sets out four that he supports, with illustrations, in a Scientific American article. I’m just going to focus here on two of them, which as Tegmark and others have speculated, could ultimately be different ways of looking at the same one. I’ll try to explain them very briefly.

The first approach: quantum divergence

It has been known since early in the last century that, where quantum physics allows a range of possible outcomes of some subatomic event, only one of these is actually observed. Experiments (for example the double slit experiment) suggest that the outcome is undetermined until an observation is made, whereupon one of the range of possibilities becomes the actual one that we find. In the phrase which represents the traditional ‘Copenhagen interpretation’ of this puzzle, the wave function collapses. Before this ‘collapse’, all the possibilities are simultaneously real – in the jargon, they exist ‘in superposition’.

But it was Hugh Everett in 1957 who first put forward another possibility which at first sight looks wildly outlandish now, and did so even more at the time: namely that the wave function never does collapse, but each possible outcome is realised in a different universe. It’s as if reality branches, and to observe a specific outcome is actually to find yourself in one of those branched universes.

The second approach: your distant twin

According to the most widely accepted theory of the creation of the universe, a phenomenon known as ‘inflation’ has the mathematical consequence that the cosmic space we now live in is infinite – it goes on for ever. And infinite space allows infinite possibilities. Statistics and probability undergo a radical transformation and start delivering certainties – a certainty, for example, that there is someone just like you, an unimaginable distance away, reading a blog written by someone just like me. And of course the someone who is reading may be getting bored with it and moving on to something else (just like you? – I hope not). But I can reassure myself that for all the doppelgangers out there who are getting bored there are just as many who are really fired up and preparing to click away at the ‘like’ button and write voluminous comments. (You see what fragile egos we bloggers have – in most universes, anyway.)

Pulling them together

But the point is, of course, that once again we have this bewildering multiplicity of possibilities, all of which claim a reality of their own; it all sounds strangely similar to the scenario posited by the first, quantum divergence approach. This similarity has been considered by Tegmark and other physicists, and Tegmark speculates that these two could be simply the same truth about the universe, but just approached from two different angles.

That is a very difficult concept to swallow whole; but for the moment we’ll proceed on the assumption that each of the huge variety of ramified possibilities that could follow from any one given situation does really exist, somewhere. And the differences between those possible worlds can have radical consequences for our lives, and indeed for our very existence. (As a previous post – Fate, Grim or Otherwise – illustrated.) Indeed, perhaps you could end up dead in one but still living in another.

Quantum Russian roulette

So if your existence branches into one universe where you are still living, breathing and conscious, and another where you are not, where are you going to find yourself after that critical moment? Since it doesn’t make sense to suppose you could find yourself dead, then we suppose that your conscious life continues into one of the worlds where you are alive.

This notion has been developed by Tegmark into a rather scary thought experiment (another version of which was also formulated by Hans Moravec some years earlier). Suppose we set up a sort of machine gun that fires a bullet every second. Only it is modified so that, at each second, some quantum mechanism like the decay of an atom determines, with a 50/50 probability, whether the bullet is actually fired. If it is not, the gun just produces a click. Now it’s the job of the intrepid experimenter, willing to take any risk in the cause of his work, to put his head in front of the machine gun.

According to the theory we have been describing, he can only experience those universes in which he will survive. Before placing his head by the gun, he’ll be hearing:
Bang… Click… Bang… Bang… Click… Click… Click… Bang…  …etc

But with his head in place, it’ll be:
Click… Click… Click… Click… Click… Click… Click… Click…   …and so on.

Suppose he keeps his head there for half a minute, the probability of all the actions being clicks will be 230, or over a billion to one against. But it’s that one in a billion universe, with the sequence of clicks only, that he’ll find himself in. (Spare a thought for the billion plus universes in which his colleagues are dealing with the outcome, funerals are being arranged and coroners’ courts convened.)

Real immortality

Things become more disconcerting still if we move outside the laboratory into the world at large. At the moment of any given person’s death, obviously things could have been different in such a way that they might have survived that moment. In other words, there is a world in which the person continues to live – and as we have seen, that’s the one they will experience. But if this applies to every death event, then – subjectively – we must continue to live into an indefinitely extended old age. Each of us, on this account, will find herself or himself becoming the oldest person on earth.

A natural reaction to this argument is that, intuitively, it can’t be right. What if someone finds themselves on a railway track with a train bearing down on them and no time to jump out of the way? Or, for that matter, terminally ill? And indeed Tegmark points out that, typically, death is the ultimate upshot of a series of non-fatal events (cars swerving, changes in body cells), rather than a single, once-and-for-all, dead-or-alive event. So perhaps we arrive at this unsettling conclusion only by considerably oversimpifying the real situation.

But it seems to me that what is compelling about considerations of this sort is that they do lead us to take a bracing, if slightly unnerving, walk on the unstable, crumbling cliff-edge which forms the limits of our knowledge. Which always leads me to the suspicion, as it did for JBS Haldane, that the world is ‘not only queerer than we suppose, but queerer than we can suppose’. And that’s a suitable thought on which to end this blogging year.

*Tegmark, Max, Our Mathematical Universe: My Quest for the Ultimate Nature of Reality. Allen Lane/Penguin, 2014

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Truth and Deception

Commuting days until retirement: 94

My very first post on this blog, nearly two years ago, was about Alan Turing, and in the intervening time his public profile has continued to grow. That post still appears to be one of my most frequently read ones (which isn’t saying much) – probably because there are so many searches for his name now.  You may be aware that a dramatised film of his life was recently released – The Imitation Game – so of course I went to see it.

Warning: some spoilers follow. If you don’t want to read on, then I recommend seeing the film, but also taking a monster pinch of salt with you.

Cumberbatch as Turing

Benedict Cumberbatch as Alan Turing (still from film)

My expectations weren’t too high after seeing the trailer, and the words splashed across the screen: ‘It took a man with secrets to break the biggest one.’  This suggests elements of the Hollywood-style schlocky mindset that we are all familiar with. However it looked as if Benedict Cumberbatch’s portrayal of Turing had some studied integrity, as indeed I found it did when I saw the film. But I suspect the celluloid Turing had far more exaggerated autistic traits than the real one: there’s no doubt that he was shy and socially awkward, but hardly quite as indifferent to the emotions of others as he was made to appear.

As I wrote in that earlier post, his impulses were more often generous and considerate; perhaps an example of this was his breaking off of his engagement with Joan Clarke, his fellow cryptographer at Bletchley, feeling that as a gay man he wouldn’t be able to maintain an adequate marriage. What private conversation took place we will of course never know,  but the film version made it more abrupt and brutal than I would have imagined it to be.

Knightley as Clarke

Keira Knightley as Joan Clarke (still from film)

The real Joan Clarke

Joan Clarke from a contemporary photo

Turing’s biographer,  Andrew Hodges, has criticised the film on the portrayal of Joan – played sweetly and demurely by the willowy Keira Knightley. I thought it was a good performance, given her brief (but should someone have told her that a double-first Cambridge maths graduate is not likely to pronounce the name of the great Swiss mathematician Euler as “Yooler” rather than “Oiler”?) I’m getting pedantic – but one of Hodges’ points was that Joan Clarke was stocky and bespectacled – not the ideal of femininity, but as such someone whom Turing would have found a congenial and comfortable companion, as he undoubtedly did. There’s some insight into their relationship in an interview she gave to BBC Horizon in 1992, four years before her death (see video clip at the bottom of this post).

I did enjoy the film, although the beautifully realised period settings were marred – as so often – by a cloth ear for the language and idioms of the time. Would a fairly patrician Englishman in the 1940s (Commander Denniston/Charles Dance) have said “You’re fired” rather than something like “I’m sacking you”? And would Joan Clarke have talked about “fixing” Turing’s lamb in an imagined future marriage, rather than “cooking” it?

I seem to be turning into one of those people who get their biggest kicks from looking for mistakes in movies; but what the hell – it’s fun, and these are the sorts of things that irritate me. And indeed I became increasingly impatient with the more serious departures from reality. For a start, there’s no evidence at all that anyone attempted to fire Turing – this was just a ladle of dramatic tension clumsily poured in to spice things up. And so it went on.

“Based on a true story”, we were told at the start. So there’s an expectation of some invented scenes and dialogue, and minor deviations from fact to help the story work as a film. If I had known nothing about Turing or his Bletchley work before seeing film I would now believe that:

  • Apart from some clerical help by the Wrens, the entire wartime decryption operation was down to four men,  one woman and a single machine which Turing built almost single-handed as well as designing it.
  • He named the machine ‘Christopher’ after his close school friend who had died, and that the machine was a sort of emotional substitute after this loss (as was a computer he later designed in Manchester).
  • Turing was effectively blackmailed by the Soviet spy John Cairncross into keeping quiet about Cairncross’s activities.
  • At the time of his arrest for gross indecency in 1951 he threw the Official Secrets Act to the wind and told the interrogating officer all about his wartime work. (This is used in the narrative as a framing device.)

These range from the absurd, through the highly improbable, to the patently false; and I have only picked out a few of the most egregious examples. Just to examine one of them: it’s true that the spy Cairncross was at Bletchley and passed details of decrypts to Stalin’s Russia. But these were not Enigma decrypts, but those of the later, more complex naval code known as ‘Tunny’, broken by Bill Tutte and decrypted by the ‘Colossus’ computer designed by Tommy Flowers – an operation which of course owed much to Turing. It’s unlikely that Cairncross would have met Turing or had any significant contact with him; but how the thought of livening up the dull old truth with a bonus spy gets those film writers’ pulses racing! According to the film, the good old Brits of course know what Cairncross is up to, and only let him release the material that suits their purposes. (How on earth they manage this without his knowledge, given that the character in the film has full access to the Enigma decrypts, is never explained.) In reality, Cairncross’s activities were not discovered until the 1950s.

Rebuilt Turing Bombe

The replica bombe in the Bletchley museum (Ted Coles / Wikimedia)

And of course there wasn’t just one machine (they were actually known as ‘bombes’) but eventually some 200 of them were installed, at Bletchley and elsewhere, to get through all the work. I don’t think any of them was called ‘Christopher’.

As is customary with fictionalised true stories,  we get the ‘what happened afterwards’  follow-up facts on the screen before the credits – but even these are sloppily inaccurate: the Bletchley code breaking activities, we are told, were kept secret for more than 50 years. The makers have apparently failed to notice that the Hodges biography on which they claim to base the film, and which describes Enigma in great detail, was published in 1983, less than 40 years after the war. And the existence of the Bletchley code breaking operation was in fact made public in the 1970s, nearly a decade before that.

There I go again; but the point at issue is whether all the distortions of the truth can be justified. The film’s producer Teddy Schwartzman has been quoted as saying that, while the makers did not want to fabricate events, there are some ‘creative liberties’. Well, that’s one way of putting it. More, I would say, that many important truths were distorted in the hope of pushing up box office receipts. I haven’t attempted to count the fabricated events,  but I doubt whether the fingers of both hands would be sufficient.

I don’t imagine that Turing himself, with his mathematician’s love of detail, would have been very happy with this portrayal. The truth of Turing’s life contained drama enough – it was unnecessary to daub the picture with splotches of gaudy dramatic invention and make such clumsy attempts to drag in a spurious emotional subtext. In a different way,  the film was as disobliging to his memory as the account by his prejudiced brother John which I described in my first blog post.

The Bletchley operation was one of the greatest examples in history of overcoming barriers to discovering the truth, as well as in helping to deceive an enemy. Unfortunately what we were given here was too little truth, and a generous helping of deception

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Another Antiversary

Commuting days until retirement: 100

I thought I had invented the word,  but on googling, I find there’s nothing new under the cybersun. Antiversary, according to my search, has been adopted to mean the anniversary of a split-up, or a divorce, rather than a wedding. Well I’m going to stick with the meaning I coined back in March 2013 at the time of my 500 day antiversary: it’s the celebration of an event a given time before it happens, rather than after*. And here I am at my 100th. Days, of course, not years; the prospect of another hundred years of commuting would find me under the train rather than in it.

Napoleon

Napoleon at the start of his ‘100 days’

“100 days” always reminds me of a prime minister who,  in 1964, before the start of my working career, gave himself that time for ‘dynamic changes to get Britain moving again’. This was Harold Wilson, in 1964, whom I am old enough to remember quite well.  I expect he was consciously taking a leaf out of the book of previous politicians – but presumably not the one who was originally associated with the phrase. This, it seems, was Napoleon, who returned from exile in Elba to rule France again, on 20 March 1815. His last cent jours as Emperor ended after defeat at the Battle of Waterloo.

It was in the USA that the yardstick of 100 days was taken up as a way of measuring the effectiveness of presidents on taking up office, and the first, and most successful, was Franklin D. Roosevelt, whose ‘New Deal’ began America’s recovery from the depression. Inevitably, later presidents, and indeed Harold Wilson in Britain, did not bask in such widespread approval after their own inaugural 100 days. Fortunately I don’t have to fight a battle or put a country back on its feet, but just coast gently towards the day when the work really begins: house and garden to be taken in hand, years of accumulated debris to be cleared, vegetables to be, grown, blog posts – and perhaps other things – to be written. How much time I will have for all that is, you might say, yet to be determined. And at almost the same time as my 100 days ends, that of another government in the UK will start. What sort of government that will be, and whether indeed it will last that long, is anyone’s guess at the moment.)

So now the much-anticipated moment has moved closer, and become certain; we’ve taken the financial advice and started to make the arrangements, and I have made my intentions public at work. I mentioned in a recent post how broaching the subject of retirement might be a bit of a conversation-stopper in terms of company culture. When I made my announcement at an informal meeting, I felt a sort of collective frisson shiver through the room, as younger colleagues suddenly sensed the proximity of something thought of as remote and unreal. “Congratulations!”, said one, with a sort of well meant awkwardness.

I’m not sure whether I deserve to be congratulated on anything, but it’s obvious to any reader of this blog how much I savour the prospect of retiring.  However after nearly fifty years of working life, with few breaks, there’s a rather uncomfortable feeling of cutting myself adrift from my source of sustenance. The only time I have known the branch I was sitting on to have been sawn off was when the company I was working for folded; but now here I am, busy doing the sawing myself. Can that be sensible?

Safety net

My pension, seen as I hurtle towards it
(Ed Berg/Wikimedia)

It’s as if I’m together with fellow workers in a building (as of course I literally am) but in the metaphorical building I’m thinking of, some, leaving for other jobs, simply take the lift down to the ground floor and walk sensibly out of the main door into another building. I’m a bit concerned about the way these suicide-related images keep occurring to me, but here’s the only retirer I’m aware of at my workplace – me – gaily jumping out of the office window on the assumption that his pension safety net is held,  stretched out, by strong hands far below.

Maybe it’s the prospect of doing nothing while being paid – it doesn’t seem real to me. Yes, I know it’s more that I’ve actually built up a fund over time by making contributions, etc etc – but there’s still an eerie unreality about the thought of spending the day doing as you please and still getting money, even if rather less than before.

So a hundred more commuting days left, which I celebrate here with strangely mixed feelings. No snatch of doggerel to celebrate this antiversary, as there was for the 500th – for one thing, I exhausted all the possible rhyme words for ‘antiversary’. For a while now I haven’t been inspired to express myself more seriously in poetry, either; but perhaps retirement will give me a chance to look out that muse from wherever she’s hiding. But I am planning to revive one poem for the New Year.

And I’ll only add that, while engrossed in tapping this into my tablet on the train, I failed to notice the station I should have changed at, and had to get out at the next stop to go back and catch a later connection. I’m not even a competent commuter any more. Definitely time to think about stopping.

*My son suggests that the word should be ‘anteversary’ (ante = before). So there we are. I can have my word and the divorcees can keep theirs.