Before the big bang there was a small ‘singularity’ (this is what physicists call it). The big bang occured and this singularity expanded very rapidly to create the universe and matter. I don’t know when light appeared i am afraid.
I think the problem with time is that it is something that humans have assigned. Before the big bang there was the singularity afterwards there was the universe and when humans came along we worked out how long ago this was based on years. Light years is another human invention based on the amount of time it takes for light to reach earth from another object in space. this light would have still travelled before humans and long after we have gone, but will it still be a light year or a year if we are not here to watch it pass by?
Sorry, got a bit philosophical then!!! really good question though 🙂 i really want to know what is outside the universe. what is the universe expanding into….? this really messes with my head! do you know?
Hello again Samuel. I’m a geneticist, so this is a little outside of my area of expertise, but here’s what (little) I know:
I don’t know if we can ever know what happened “before” the big bang. I don’t know if the question even makes any sense. Physicists think that the big bang was the start of everything in our universe, and that includes time. It’s something I’ve struggled to get my head around (there’s lots of bits of physics I struggle to get my head round), but apparently there was no “time” before the big bang. Time as we know it was created with the universe – that’s the answer St Augustine gave way back in the 5th century and it seems that modern physics backs that up. Except without neccearily involving God.
I’m not too sure about light either. At it’s simplest, light is a form of electromagnetic radiation. I don’t know how, or when that came to be.
Sorry if that didn’t make things any clearer. I’ll see if I can find a physicist who knows more. 😀