Philosophizing at the Death of the Universe

I've just completed the fourth week of my excellent and highly thought provoking Futurelearn course "Gravity", and we've been discussing the supremely headscratchy topics of dark matter - matter that we wouldn't notice if we walked into a room stuffed with it despite the fact there's 5 times more of it than normal matter in the universe - and also dark energy, energy that drives the expansion of the universe, and forms nearly 70% of the Universe despite the fact we've never detected it.

Dark energy in particular is a concept to put your brain through a blender. It corresponds, it is theorised, to the vacuum energy permanently blazing away in space time, an energy produced when a particle and its anti matter equivalent are produced FROM NOTHING and then annihilate each other back into nothingness so fast that we can never possibly detect them.

At the quantum level, creating matter and energy from nothing is allowed. Providing it goes back into nothingness faster than fast can be, this is allowed. Whereas light and gravity act as a brake on the expansion of the universe, vacuum energy does the opposite. It sucks space-time away from itself. And it is doing so at a faster and faster rate.

The expansion of the Universe is accelerating. It will never stop, contract, fall back on itself in a big crunch. The Universe will go on forever.

This sounds fabulous, but it isn't really. It doesn't mean that life will go on forever. Space-time will expand forever, but the Universe will die. Fundamental particles like protons will all decay; the atoms that make up you and me, many of which were around at the time of the big bang, will all splutter out into massless ghosts. As the Universe expands faster and faster, we will see less and less of it as it disappears over a kind of cosmic horizon provided by the speed of light. The longest living stars, red dwarves, will eventually peter out and the universe will be dark and cold, apart from black holes spinning silently in the blackness. And even they too will waft away bit by bit, trillions upon trillions of years hence. No life. No light.

I find it distressing, from a philosophical point of view. In a sense, it means that life is pointless, no matter it does anywhere in the universe to improve itself, it is doomed to fail. There's no point to anything. We cannot defy the laws of particle decay.

Yet I still wonder what hope there could be for life? The only hope that I can see would be to start another universe, a universe with renewed matter and vigour, and leave our ageing protons behind and transfer to a new vessel, within the new universe. Shades of "Being John Malkovich", I realise! Anyone who knows how to start a Universe, your Nobel prize awaits.

Or we could hope that the multiverse theory of everything is correct, that our Universe is merely one of many universes floating around within an 11 dimensional membrane, occasionally triggering new Big Bangs when they brush up against themselves. Here, life could find a way of tunnelling from one universe into an other, or a newly created one, and continue to do so as energy potential runs out in each Universe it colonises on a timescale that makes eternity look like the blink of an eye.

For I do no want life to fizzle out, in a cold sweep of darkness' cloak.

Si

All text copyright CreamCrackeredNature 19.11.15