Uncomputable Insight

May 11, 2009

My Turing Test post turned out more interesting than I expected. Playing iGod was fun, and just that; but Steve’s link to a musical Turing Test really surprised me. Looks like speech is more quintessentially human than music … this is a challenge to those who see Mozart as a higher art form than Metal. Bach may be easier to fake than Beatle’s lyrics.

Meanwhile I finally finished “The Emperor’s New Mind”. As various folk said, here and privately, although its a fantastic overview of various parts of science, the “consciousness as quantum gravity” line does not end up being convincing. However .. the basic idea that human minds do something uncomputable is intriguing. Its closely linked to an issue that bugs me about mysticism, and especially Taoism and Zen Buddhism.

There are some aspects of Zen/Tao that fit well with the scientific outlook. Mysticism is not misty and vague, but rigorously insistent on the physical world, as opposed to the mental constructs we mistake for the world. (Including the fairy tales the West calls “religion”.) A classic Zen lesson is to hold up a book and ask the pupil what it is. “A book” says the pupil. “No” says the Master, “book is a noise.”. He plants it firmly in the pupil’s hand. “This is what this is”.

Anyway, what Zen and Science have in common is the belief that there is a real concrete world, and that there is a route to knowledge of the world. In both cases we carefully observe the physical world. But beyond this the (official) methods of Science and Zen diverge. In Science the route to truth is a kind of loop around guessing, testing, and refining, together with eternal scepticism. In Zen, there is first a kind of Brechtian alienation, to shock the mind out of false assumptions; but this goes with a belief that once you do that deconstruction, you already know the answer. You meditate on the flower until “The Flower” fades from your mind and your eyes see … the real flower.

Hopefully you get the link back to Penrose. Zen says that you can know the truth all-at-once, that the mind can do this. Science ..or at least textbook scientific philosophy – says you can’t. But of course many scientists also place great stock on insight, intuition, creativity etc. And push a little harder and scientists split into positivists (its meaningless to ask about essential truth; you can only know what works) and Platonists (we may be wrong at any stage, but our aim is to describe reality).

Can we know the world, or is our knowledge ever provisional ?


Stone Lions and the End of Particle Physics

September 22, 2008

On Thursday I attended a meeting of the SLAC User’s Organisation (SLUO). Half the talks were about astrophysics, and even some about light sources, but the tone and the worry was dominated by particle physics and its position in the US. There were talks from suits at DOE, the NSF, and the OMB, all of whom had warm words and encouragement, but also barely coded hints about the scepticism in Washington. “Why does it have to be so all or nothing ?” and “does the US really need to lead this area ?'” and of course “whats the economic impact” ? Its very frustrating because the people in power do believe its gripping stuff – thats not the problem –  and with the LHC switching on the next few years will be very exciting  .. but they don’t see where its going, why it has to cost so much, or why anybody needs a big machine in the US, as opposed to some postdocs analysing data. Strikingly, the afternoon had several talks from particle physicists who were re-training themselves as astrophysicists, who explained how much fun it was. More of them later …

Two days later I was catching a flight from San Francisco to London, for a two week stint of back-to-back meetings in the UK. I am typing this about thirty hours later, still only mid-Atlantic, having been booked at various times on seven different flights (involving five different cities) only three of which I have actually been on … This sort of thing hasn’t happened to me too often I am glad to say, but periodically every traveller hits a nightmare journey like this. At first you get real tense, and your adrenalin rises as you try to calculate the options and optimise .. but eventually you just figure what the heck, when I get there I’ll be there, and you start joking with the flight attendants stuck in the same situation.

Suddenly I remembered a poem I read many many years ago. I can’t remember the title or the author, so if the the poet happens to read this blog one day, please forgive me for stealing your idea uncredited. It was in a magazine called Crabgrass. So here is my clumsy prose rendering …

… one morning the citizens of London wake up to find the streets entirely filled with stone lions. Motion is impossible. Half the workforce get on the phone, try to figure out a way round it, register complaints, send apologies to bosses and instructions to underlings, and so on, but all to no avail. The other half stare for a few minutes, then go back inside, make some coffee, read a book, and have an unexpectedly pleasant day.

You join the dots.


Quantum Mysticism : not as good as Pooh

March 28, 2007

I am trying to get to grips with David Bohm and failing utterly, as much through boredom as stupidity..

The low-l anomaly in the cosmic microwave background, discussed by Andrew Jaffe in his seminar here last week, gets people excited because it hints at a violation of causality. Long distance quantum entanglement excites people for much the same reason. You spit out a pair of particles that must have opposite spins, but the spin of either one is not determined until it is measured. So then you measure one, and instantaneously force the other, distant, particle to have a specific spin. The laws of physics, some say, are in a deep sense non-local. Everything is connected. Err…

If you google “everything is connected” you mostly get lots of wishy washy mysticism, with the odd bit of quantum mechanics thrown in. Well, as you will see from some of my posts, while I am vaguely antagonistic to Western religions, I find Eastern mysticism very interesting, while trying to stay healthily sceptical. This sort of interest is of course quite normal for someone of my age whose hair used to be much longer and who still has some pink loon pants somewhere in the attic, and who occasionally plays his crackly Steve Hillage albums on his Rega Planar. (Now we’re all reality gypsies).

So there I was in the bookshop and found myself picking up “Wholeness and the Implicate Order” by David Bohm. The blurb says he is not only famous for his hidden variables interpretation of quantum mechanics, but was inspired by Eastern Philosophy, and blended the two to arrive at a new way of looking at the Universe, including consciousness. Wow. Can’t wait.

A week later I have managed a few dozen turgid pages per night. The bits of physics in it do look really interesting, but I’d have to read the real papers to be sure, and my brain hurts already. But the philosophy seems to be vapid gibberish. Its full of pointless neologisms, repetition, obscure phrasing, and a kind of Vedic philosophy muddled and watered down to a sort of murky soup.

I’d hate to think anybody would think this is what Eastern philosophy is really like. Better to go straight to the Tao Te Ching. Or possibly even better, the Tao of Pooh.

Or maybe just read The House at Pooh Corner. Alternated with chapters from the Feynman Lectures.