Big Bang/Something doesn't add up

[ManInTheMiddle]

(Or, teach me 101)

OK, I was looking at this: http://www.newscientistspace.com/art...d=space_rss091

And I began thinking ( ). How do they know they're looking in the right direction? Hey, the "Big Bang" was supposed to start at some specific point in seething mass/energy form. Conversely, it doesn't matter what direction one looks with yon Hubble to see back in time. I assume that if, it was in the wrong direction- all one would see is darkness.

Is this correct?

(Probably, a really dumb question)

[Nacho]

ManInTheMiddle,

How do they know they're looking in the right direction?

Because, susposedly, any direction you look you see the same thing. And that is because of a couple of things:

1) Inflation .. if you believe it .. This happened in the first few instants of the BB. The Universe expanded by many more powers of magnitude than it does now, and many more powers of magnitude greater than the speed of light, then settled down to our "normal" expansion. Light would not have had time to reach us yet from the furtherest reaches of the Universe that were "stretched" out by Inflation, and might never. What we are able to observe now may be but a miniscule of the extent of the Universe, and what "Inflation" stretched out was to make all of space to have relatively equal parts of matter/energy.

2) All 3 spatial dimensions of space are expanding, and at the same rate .. or at least I've never heard an argument yet that 1 or more of the 3 spatial dimensions are expanding at a different rate than the other(s). Thinking of it as a balloon expands into 3 dimensional space is a good analogy, but it can't be taken too far. You can't consider yourself in the "inside" of the balloon, closer to 1 side of the surface than to the opposite, and think: "Hum, there are places in here that I am farther apart from than others." That stretches the analogy too far. It would be better in that instance to think of yourself as a 2 dimensional creature on the surface of the balloon, and realize the balloon surface is 2 dimensions, but using the 3rd dimension in which to expand its surface area. Anywhere you look you see the same thing. Every point on the surface can be considered the "center of expansion", as you only know about two dimensions, and as the balloon expands (inflates), more space is introduced between you and what is standing around you .. everything on the surface moves apart .. and every place looks to be the center of expansion. The "true" center of expansion though is at the center of the balloon, in that 3rd dimension that you, a 2 dimensional being, know nothing about.

Now, even the analogy I used falls apart too. Our 3 dimensions are expanding, like the 2 dimensions on the surface of the balloon, but there is no evidence that our 3 dimensions are utilizing/using a 4th spatial dimension to expand within.

[ManInTheMiddle]

Nacho, thanks for the great answer!

I had a hunch that someone around here would have the cure for my "perceptual problem".