Professor Brian Cox told us all about the universe in Nottingham last night. It wasn’t a lecture because we were drinking cosmic beer and no-one fell asleep, but an awful lot of information poured out in fast-flowing Mancunian, devoid of pauses and punctuated by lots of smiles. At one point half way through I thought I understood Einstein’s General Theory of Relativity. But this morning I realise that with every passing second more of that knowledge is slipping away into the space-time continuum and so I need to get this blog down fast.
It’s all about time and space, you see. They are sort of woven together into a big inter-galactic blanket. I could definitely time-travel into the future (theoretically and relatively speaking), as long as I moved my second mirror to a more obtuse angle while yours stayed in the same place. But I can’t go back in time because my light cone doesn’t extend backwards and even if I could swivel it round I might get torn to pieces on the journey. To be honest, I don’t know why I’d want to go back in time anyway, except perhaps to discover where I left my glasses, or avoid missing that train on Tuesday.
We can see back to the past, however, even if we can’t travel there. At least we could if the council would turn off the street lights at night. Every time we look at the stars we see the universe as it was millions of years ago, because of the time it takes light to travel. The Hubble Space Telescope, which doesn’t have to cope with light pollution or atmospheric distortion, has looked back as far as only a few hundred thousand years after the universe came into being. If, indeed, there was a starting point (Prof. Cox seemed sceptical).
We don’t need to ‘see’ everything to know how the universe, all its galaxies, stars and planets were formed, because Einstein’s beautiful theory allows Brian Cox to calculate it for us. Except that relativity can’t explain exactly what happened in the very first hundredths of a second after the Big Bang. Careless that, but it creates the opportunity for Brian to speculate.
Human beings are very, very small and insignificant in all this. There are a two, or possibly, four hundred billion stars in our galaxy (astro-physicists don’t seem to worry too much about size if the differential is only a factor of two), and there are a billion-odd galaxies in our universe, and quite possibly lots more universes in the multiverse. So it is very probable that there is other intelligent life out there. Indeed, as our solar system is quite young, some of alien civlisations may have been and gone before human beings learned to walk and play the guitar. But it is also theoretically possible that life elsewhere never progressed beyond the single-cell stage. We don’t know to be honest.
In fact, we might never know because lots of information gets lost into black holes, like the way boarding cards disappear in the moments before they start calling my name on the airport tannoy. I don’t know why facts and figures would stray into the gravitational pull of the a black hole in the first place, but I suppose some data just has a risk-taking personality, like Icarus getting cocky and flying too close to the sun. But maybe it’s because they read the same books as Prof. Cox and trusted that it is possible to get into the orbit of a black hole without getting sucked in.
Even once you cross the black hole Event Horizon it is apparently all fun and games from your perspective. You would barely notice being stretched out like a piece of spaghetti as different parts of your body struggled to exist in multiple time zones. I suppose things can only get better from that point on. Sorry.
So life might go on in a black hole, but from the perspective of someone observing your journey from a safe distance, you would be standing still for eternity. That’s because no light can travel back across the event horizon because the angle between your first and second mirror will have become so acute as to be essential infinite.
We need to know about event horizons because there’s a black hole at the centre of every galaxy and we are basically floating in a swarm of galaxies, all of which look indescribably beautiful on the big screen at the Motorpoint Arena. At this point (it may not actually have been at this point in the show in a strictly chronological sense, but space-time is all curvy so linear narratives are unnecessary) Prof. Cox reveals a penchant for astro-poetry, re-utilising passages from Erasmus Darwin and Wordsworth which opened the show, and reminding me just how much I am looking forward to getting back to the dark skies of Wales the following day. But he doesn’t get carried away with the artsy stuff for long and is soon bringing it back to physics.
This is when Robin Ince, in his guise as a human attention-deficit barometer, bounces back on to the stage (Coxy just magically appears, like the store-keeper in Mr Ben) to deal with the danger of the audience getting overwhelmed by the torrent of information, and re-energises us with tales of den-building in the woods, or reads out questions from impossibly well informed eleven year olds. Coxy knows all the answers, of course, and even throws in that he has ejected more photons (or was it protons?) in the time we have been listening to him than there are stars in the galaxy.
There was lots more, including about the time Jupiter nearly crashed into an infant Earth but was dragged away by bezzy-mate, Saturn; the probability of microbial Martians; and the impossibility of travelling faster than the speed of light, which we all have to agree about at the start before Professor Cox is willing to tell us about the rest of life, the universe and everything.
Mostly, however, I remember that we can’t turn back time. But is that true? My sister gave me these Brian Cox tickets as an Xmas present in 2017, not noticing that the show wasn’t until February 2019, so in some parallel universe it was 2018 last night and so maybe I know something Brian Cox doesn’t know after all?