Wednesday, March 14, 2007

Quantum Graffiti





I’ve started cycling to work. It’s great, though I recently discovered my brakes don’t work in the rain. I’m lucky to have a rather pleasant route; briefly through Botanic Park, along the towpath by the river and then I have my own lane as I pedal the Ormeau Embankment. After that it gets a bit scrappy, but I’m not complaining.

Thanks to a certain questioning mural artist, every morning on my way to work I’m left considering how quantum gravity might help explain the origin of the universe. Hmmm... how could it possibly? Oh, wait a minute - what the hell is quantum gravity? This, I suspect, is part of the artist’s vision. I don’t know who the artist is, but perhaps, as a ram-pressured space rock flew through the earth’s atmosphere, she hoped that passers-by would investigate this area of physics. Or maybe she is unconvinced that quantum physics has anything to bring to the discussion of where the universe came from, and she wished upon that shooting star that we would just look up and be amazed.

Well, I went with the former. A quick search in wikipedia pointed out that quantum gravity is basically the missing link, as it were, in the well known “Theory Of Everything”; that holy grail in which physicists try to piece together the three fundamental forces of quantum mechanics (electromagnetism, and the weak and strong interactions) with general relativity’s fundamental gravitational force. You’ve heard of it before. They’re still working on it.

And, would you believe it, quantum gravity does indeed throw its tuppence into the discussion pot. As opposed to conventional Ex nihilo theories (that appeal to the traditional religious mind), M-theory, according to some of its proponents, suggests that the universe was birthed when two multidimensional membranes (often called 'p-branes', I kid thee not) collided into one another. And, if the theory is correct, the number crunching tells us that the observable universe in which we live is an 11-dimensional spacetime.

I’m lost. But it is fun, isn’t it? I like living in an 11-dimensional universe, having always felt a little constricted in the four I can name.

String theory (M-theory being big in this field as it ties five superstring theories together) is very popular, but I’ve heard some rebels are beginning to doubt its afore-assumed messianic potential of unifying quantum theory and relativity. Academia, having spent 30 years delightedly muttering “surely” to string theory, have among them doubters who propose a new tack - one of creative thinking (in the style of Einstein sitting atop a light beam, I suppose) - in an effort to crack this quantum nut because, after all this time, the sums still don‘t quite add up. Less mathematics around the assumed answer, and more guessing outside the box, suggests Smolin, for one. He likes to encourage lay folks, like myself, by confessing that physicists are as befuddled as the rest of us.

Looking back to the mural, I pause a little longer, and consider the artist’s other question. For it can be no accident that if we drop the last line the question becomes, “How can quantum gravity explain theo?” Nice touch. It already felt like we were delving into the realms of philosophy and religion as we tagged along with the outer stretches of the physicists’ minds as they searched for the impossible equation. Though not interchangeable, there are surely similarities in the two questions. For if God spoke and, (in a theoretically rather old-fashioned manner for Almighty to choose) Ex nihilo, there was, we are still left with the mystery of God‘s beginning. There is delight when answers slip perfectly into the puzzles we‘ve been working on, but the questions, too, bring a joy. Unanswerables - for now at least. I will look up and be amazed.


Thanks to the wikipedia authors :-)
click for tv shows on string theory

1 comment:

Jorgi Reus said...

Once in Belfast I saw this non-political mural...Im very happy to read it again, it was painted on a wall close to my flat...Thank U very much


JorgiReus @ FB