One thing about this project that I’m really pleased about is the fact that I read ‘A Briefer History of Time’ by Stephen Hawking and thoroughly enjoyed it. It made my head go a bit funny. It had never really occurred to me but apparently space and time began with the big bang. They’re both entirely relative. That fact in itself is pretty mad. Time moves more slowly when closer to a strong gravitational force. This is part of how a hypothetical astronaut who travelled through the universe at light speed would be younger than their twin on their return to earth.
Apart from this, I’ve been getting quite excited by the Large Hadron Collider and the things they’re trying to find out from those experiments. I’m fascinated by the fact that, in order to recreate the first milliseconds of the universe scientists have to look at things on such an infinitesimally small level, and that that’s how our universe began. Before the big bang there was nothing. I’d always thought that meant there was an infinite expanse of nothingness, but I was wrong. The truth is so much less comprehensible than that. In fact there was nothing at all. Nothing. Apart from perhaps an infinitely dense particle, though as of yet we can’t know because this is one of the things this experiment was built to discover. The very first miliseconds after the big bang we’re still in the dark about. With space and time being relative to gravity, though, and there being no gravitational fields to speak of, before the big bang, there was, presumably, quite simply no such thing as time. Though again, this is conjecture. We just can’t know. Yet.
Hawking has this to say about it:
…at some point in the past (about 13.7 billion years ago), the distance between neighbouring galaxies must have been zero. In other words, the entire universe was squashed into a single point with zero size, like a sphere of radius zero. At that time, the density of of the universe and the curvature of space-time would have been infinite. It is the time that we call the big bang. All our theories of cosmology are formulated on the assumption that space-time is smooth and nearly flat. That means that all our assumptions break down at the big bang. That means that all our theories break down at the big bang: a space-time with infinite curvature can hardly be called nearly flat! Thus even if there were events before the big bang we could not use them to determine what would happen afterward, because predictability would have broken down at the big bang.
I figure this means that space and time had a beginning. Year dot. And further to that, outside of the universe there is no space-time*. Does this really mean then that there’s nothing outside of the universe, at least in the space-time sense? And when the universe was that point of zero size, was the void what was outside of it? Just to clarify, what I’m getting at isn’t about God. I’m just trying to imagine something without space-time. I can’t because something without space-time simply isn’t something. Though I could be wrong and probably am. So I try to imagine what this nothingness might feel like. Would it be heavy? Obviously this isn’t relevant. What is? How can I represent it? Every empty thing looks full, as perhaps that actual nothingness was in itself. I suppose it must have been. Look at what came from it. I’m also trying to get my head around what might be beyond the universe. More nothing? What could more nothing be? Can you even have more of something that doesn’t exist? Though, saying that, if you could go out in to the nothingness surrounding the universe(?) it would then become part of the something that is the universe. What is nothing then? Is it nothing? I think I might consult the oracle about this. The oracle being my friend Dave who knows about these things. Or at least he knows more about them than anyone else I know. There are so many things here that I’m struggling to understand. I’m repeating myself at certain points in this blog but I kind of have to. I’m unsure how I can’t not repeat myself.
Though looking back at what I’ve written here, there are other questions that confuse me even more. The void outside of the universe is nothing. Which means exactly what it says. The universe isn’t expanding into nothing because there’s nothing there in to which to expand. And what is infinite curvature? How can infinity be contained in a sphere of zero size? Was there an infinity of inwardness in that zero point sphere? On a personal or spiritual level this all looks like it makes perfect sense. I click with it fairly easily. On a more intellectual level I really don’t get it. That’s probably not too unusual.
One other thing that confuses me about the quote form Hawking is the way he describes the distance between neighbouring galaxies as being zero. My understanding is that galaxies didn’t exist and couldn’t because the point of zero size was (thought to have been) infinitely hot. They only came into being when the universe had had a bit of time to spread out, cool down and so on. I think he’s just speaking figuratively though. The seconds and then years and millennia that follow the big bang are incredible; all of the quantum fluctuations and helium/hydrogen explosions. Hawking offers a timeline of events for the first hundred seconds of the universe after the big bang, not including the very first milliseconds. They’re the bit the LHC is investigating. The picture it presents us with is one of immense change, of things rapidly coalescing and shifting. It’s all a bit nuts. And in the midst of those explosions were the beginnings of our galaxy, and our solar system, our planet, our newspapers, our desire for new kinds of coffee, our ability to reflect on all of the above. If I had a time machine that would have to be one of the moments to go see, even if it would be impossible on so many levels.
There’s an amazing dichotomy here, between nothing and everything. But what is everything? The tension between the two excites me. Did the explosion create more space the further outwards it moved? What was gravity like in those first seconds? How fast was time moving? Does that even make sense? If time is relative to gravity, does that mean the perception of time for a person in a different gravitational field remains the same? Would that astronaut traveling at light speed perceive time differently to when he was on earth? If time is such a relative concept, are completely different conceptions of it possible? Are there parallel universes in which the idea of time is completely different? And how much of this post has consisted of me ranting about things of which I know almost nothing? I’ll probably talk to Dave and realise everything I’ve written here is totally irrelevant. Maybe I’ll write a shorter summary post in a few weeks that clarifies any confusion in this one.
* – Interesting how they call it space-time instead of space and time, or space time. They’re condensed into one entity, almost, by the hyphen. One can’t exist without the other so they come close to being one word. One entity. Can we have time without space? Or space without time? I like the fact that the hyphen stops them from becoming one entity as well. It’s also a wall between them.