Expert: Ed - 6/7/2007

Question
I can't seem to wrap my brain around the thought that space did not exist at some point in the past. Maybe I don't understand what is meant by the use of the word "space". I think of space as infinite in every direction, and every other thing that exists has to exist in space. I hear about space being curved or spherical or expanding, and I can't understand how space in general can have any boundaries. For example if you come to the “edge of space” doesn’t there have to be something (at least space) beyond that? I’m sorry if this question seems odd; but I was hoping you could help me understand this thing called space.

Thank you
Burt  

Answer
Burt,

Yes, this kind of thing drives me insane too.  Here is my two cents worth.

You might want to try thinking of "spacetime" as the thing that is curved, not just "space."  That is more proper, and it should help alleviate some of your stress.

Spacetime is thought to have mathematically existed since the Big Bang, or about 13 and a half billion years.  If you think of it in this way, you will see that it doesn't make sense to ask what existed BEFORE spacetime, because for something to predate the "time" part of spacetime implies that time exists in a larger chronological context.  

The idea is that time itself began at a particular point, a point in both time and in space, at the beginning of each.  This was the Big Bang, which created spacetime as we know it.

Here is a related concept, which I think might be useful for you to ponder.  Have you ever wondered if you could see, when you look up in the sky, the exact point where the Big Bang happened?  When I was little, it always seemed like there ought to be some direction that I could look in, and see where the universe began.  Well, that is incorrect.  The whole idea of spacetime beginning means that ALL of space and time originated together.  The Big Bang did not happen at a point that you could look up and see, in Orion's Belt, for example.  It happened everwhere, all at once.  It was, by definition, the beginning of all places, all space, and of all time.  So, when you look at the sky, every direction you look in, you are always, always looking in the direction of the Big Bang.

If you think it over, you will agree with me that that should help you think about your question.

Having said this, I should point out that physicists Steinhardt and Turok are currently trying to question the underpinnings of this framework, by positing the idea that time and space keep starting and restarting every few billion years, like the beating of an enormous heart.  This might just confuse you more, so I leave it up to you whether to click on the link:
http://www.spacedaily.com/news/cosmology-02c.html

Here is a good link to check out sometime:
http://www.astro.ucla.edu/~wright/cosmology_faq.html

Keep Looking Up!
--Ed