26 August 2017

Eating weetbix at the speed of light

You’re not sure how it happens, but one day you’re assembling your breakfast — bran flakes, a couple of spoonsful of rolled oats, raisins — and you reach into the giant packet of Weetbix you’re sure you bought just a week or two ago, all seventy-two biscuits, which you’ve been crumbling into your bran flakes and rolled oats and raisins at the rate of just one a day just two or three times a week, and you realise that suddenly, unexpectedly, you’re several layers down in the packet, approaching the halfway mark, and the maths just doesn’t add up.

The only explanation is that you must have bought the packet months ago, not weeks ago, but surely time can’t be passing that quickly? Maybe your breakfasts — your breakfast times, that is — have been too enjoyable. Einstein once explained relativity in relatively simple terms by pointing out that when you’re with a beautiful woman, time flies past, but when you’re sitting on a red-hot cinder, the moment goes on forever [1]. It’s an analogy most of us can relate to, at least in part and adapted to personal preference and experience.

But, had I really been having that much fun during the course of my Weetbix-depleting dawns? If time had speeded up as I sat at the kitchen table, reading what had happened overnight in the world, or — if I’d risen late enough — looking out the window at the violet dawn  and the blackbirds tugging their breakfasts in long, elastic, resisting threads from the soggy pasture, then who had been eating the missing Weetbix? Had another parallel version of me been crumbling Weetbix while I looked out the window and thought of birds and beautiful women?

If I wanted my life and my Weetbix to last longer, would I have to find a red-hot cinder to sit on?

Another thought crossed my mind. If I could eat breakfast faster than the speed of light, time would start to move backwards and, presumably, my Weetbix box would begin to fill up. With sufficient practice, I could eat at the speed of light, in which case time would stand still and I could survive on just one Weetbix until, … well, the end of Time.

None of it made any sense, which is such a common feeling for anyone trying to understand pretty much anything about modern physics that it was a completely unsurprising feeling. Besides, I’ve always been the slowest eater I’ve ever met, and the only way I was ever going to eat at the speed of light was if I existed in a parallel universe. That might have made perfect sense to Richard Feynman, whose theories were instrumental in developing the idea of parallel universes and was probably the only person who could explain them intelligibly [2], but two things meant I was unlikely to be able to get my head around the concept that I might meet myself somewhere, sometime parallel to where I happened to be. First, Feynman was a genius and I’m not. Second, and sadly, Feynman died many years ago [3], so I’d never get the chance to sit down and talk with him and hear him explain incomprehensible concepts comprehensibly — unless, of course, I met him in a parallel universe in which he hadn’t died.

Modern physics isn’t something most of us can pick up easily. For a start, you need to know the maths, and that’s a long and arduous apprenticeship. The effort might be worthwhile, though —advanced maths is, by all accounts, an end in itself, a reward in itself. Bertrand Russell described mathematics as having a ‘supreme beauty’, ‘sublimely pure’ — but he, too, was a genius. A different kind of genius, admittedly, but he shared Feynman’s genius at mathematics, so he was well placed to pass that kind of judgement. I’m not, so I have to rely on belief that he was right, and belief, as any competent scientist will tell you, is dangerous and not to be trusted.

But, if you don’t have the mathematical training and flair, you have to rely on translations from mathematics to everyday language, and only a handful of writers have those twin skills of advanced mathematical competence and great facility with written language. Thank the cosmos that we have at least a few of those — Brian Greene is a great example, as is Stephen Hawking (although some will disagree with that assessment [4]) — but when you’ve finished reading their works and you still have questions, it’s not like you can figure it out for yourself. The analogies those interpreters have to use do a good job of explaining what they’re trying to translate, but here’s the problem: ordinary mortals like you and me can’t confidently extrapolate the analogies. In other words, we can’t know whether our extrapolations are valid. You’d have to ask the translator, and because few of us will ever get the chance to query Greene or Hawking, we’ll never know whether they’d nod and agree or shake their head and say, ‘No, the analogy doesn’t work for that.’

So, for the time being, I’m forced to keep wondering why my Weetbix are disappearing faster than apparently explained by the Laws of Physics, and I guess I’ll just have to enjoy them while they last — while, that is, I have time.

1. I’ve taken liberties with the phrasing of what Einstein said, but because the quotation appears to have been indirect, I’m comfortable with my liberties.
2. OK, I’m taking serious liberties with the history of the Many-Worlds Interpretation, mainly because I don’t understand it, but the main point is that if anyone could comment sensibly on it, that person was probably Feynman.
4. Until Thomas Piketty published ‘Capital in the 21st Century’, Hawking’s ‘A Brief History of Time’ was considered the least-read best-selling book.

I had no idea about what photographs to include (there's a challenge for better photographers than me: make weetbix look interesting), but then I thought, well, birds don't wonder about these things. They just get on with it, and if there's maths to be done, they just do it without a fuss.
1. On the other hand, maybe tui are solving complex abstract mathematical problems when they're singing. Their songs are so astonishingly complex that anything might be possible. And yes, that's its tongue.
2. Sparrow getting on with its day.
3. At Massey University, the waxeyes and other birds have been feasting on the spring nectar.

Photos and original text © 2017 Pete McGregor