Some musings on the beginings of things

An old-fashioned looking black and white line drawing of several men in suits and hats playing pool.

“Everything starts somewhere, although many physicists disagree.

But people have always been dimly aware of the problem with the start of things. They wonder aloud how the snowplough driver gets to work, or how the makers of dictionaries look up the spelling of words. Yet there is the constant desire to find some point in the twisting, knotting, ravelling nets of space-time on which a metaphorical finger can be put to indicate that here, here, is the point where it all began…”

– Terry Pratchett, ‘Hogfather’

Cause and effect

If a white cue ball strikes a black eight-ball on a pool table, the black ball will go flying. The white ball’s motion is the cause, and the black ball’s motion is the effect.

Cause and effect is a strange way of understanding things, when you think about it. If X caused Y, what caused X? Perhaps it can be worked out that W caused X. And perhaps W was caused by V before that, and perhaps in theory you could follow the chain of effects and causes all the way back to the Big Bang. Is this what ‘understanding things’ is supposed to mean?

Conservation

“The conservation of energy is not an option, it is a fact. This is the first law of thermodynamics. Special as we humans are, we get no exemptions from the rules. All animals eat plants or eat animals that eat plants. This is the food chain, and pulling it is the unique ability of plants to turn sunlight into stored energy in the form of carbohydrates, the basic fuel of all animals. Solar-powered photosynthesis is the only way to make this fuel. ”

– Richard Manning, ‘The Oil We Eat: Following the Food Chain Back to Iraq’

Another way of trying to make sense of the world is to focus, not on cause and effect, but on conservation. The balls on the pool table move the way they do because the total momentum is conserved. You can line up the initial and final motion vectors tip to tail and get a closed triangle, with the sum of the final vectors equal to the initial one.

A diagram showing two balls, one white and one black, on a green pool table. The white ball is struck with a pool cue and in turn strikes the black ball. Colored arrows represent the motions of the cue and the balls, and the arrows can be arranged to form the sides of a triangle.

Conservation is (arguably) the basis of all physics. There are lots of different things that get conserved; sometimes it’s mass, sometimes it’s energy, sometimes it’s mass-energy, sometimes it’s momentum, sometimes it’s electric charge, sometimes it’s something really weird like ‘quark color charge’ or ‘weak isospin’.

But at its core, all of physics relies on the conservation of something or other. That’s why physics has so many equations. An equation is just a way of saying: this stuff might move around, it might change its form, the left hand side might sneakily multiply itself by -1 and move over to the right, but stuff doesn’t just appear out of nothing, and it doesn’t just wink out of existence either.

The Big Bang

The Big Bang can never be explained by physics.

Physicists can notice how all the galaxies are flying apart from all the other galaxies, and they can work backwards from that to say that there must have been some point, just before everything started flying away from everything else, when everything was in the same place, and took up no space at all.

Yet the Big Bang itself lies outside of physics, because the Big Bang is where something* appears out of nothing. It lies outside of the most basic set of assumptions that physicists must use in order to say that something caused something else.

* The whole universe, actually.

To make something new

But, given that all the stuff in the universe has been around in one form or another since time began, how does anyone ever make something new?

The answer is simple. We make something new by converting some stuff into some other kind of stuff, and then pretending the first kind of stuff never existed. We make new wooden furniture by pretending we never saw a tree, we make new plastic goods by pretending we never heard of an oil well, or a landfill site. We make brand new clothes by forgetting about cotton farms, sweatshops, and the great container ships that cross and re-cross the oceans.

It is an idiosyncrasy of this culture and this particular point in history that almost everything in our lives appears to us to be new. We only look (we are only allowed to look) at the little bit of the world that is directly in front of us. Things appear to us without any context. We don’t see the wider processes that our stuff is a part of.

We don’t see the wider processes that we ourselves are part of. We appear to ourselves as something isolated and new, something that sprang from the ether fully formed, without debts or obligations, accountable to nothing outside itself.

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Images credits:
Men playing pool by j4p4n, public domain
Pool table momentum conservation by anarres, public domain

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