that's what their observations of the night sky suggested. Needless to say, this view

clashed with the "origin" or "creation" stories of most major religions, which hold that the

universe had a beginning.

So it's not surprising that it was a Catholic priest, Georges Lemaître, who was one of

the first major proponents of a new scientific viewpoint - that the universe DID have a beginning.

Lemaître, of course, was also an excellent mathematician and scientist and based this

conviction not (just) on his religious beliefs but upon new experimental evidence from Edwin

Hubble that showed the universe was expanding. This evidence, combined with the mathematics

of general relativity allowed Lemaître to "rewind" cosmic history and calculate that

the farther back in time you go, the smaller the universe had to be. The natural conclusion

is that everything we can currently see in the universe was at one point in time more

or less at one point in space. Lemaître called this idea the "primeval atom", but of course

today we know it as "the big bang theory".

Except "big bang" is a horrible name - it would be much more accurate to call it "the

everywhere stretch". Because one of the most common misconceptions about the big bang is

that it implies that the entire universe was compressed into a single point from which

it then somehow expanded into the surrounding... nothingness? It is true that the observable

universe, that is, the part of the whole universe we can see from earth, WAS indeed shrunk down

to a very very small bit of space, but that bit of space was NOT a single point, nor was

the rest of the Universe also in that same bit of space.

The explanation for this is the magical power of infinity. The whole universe is really

big - current data show it's at least 20 times bigger than the observable universe, but that's

just a lower bound - it might be infinite. And if you have an infinite amount of space,

you can scale space down, shrink everything to minuscule proportions, and still have an

infinite amount of space. Kind of like how you can zoom out as much as you want from

a number line, but it'll still be an infinite number line.

Essentially, space doesn't need anywhere to expand "into" because it can expand into itself

and still have plenty of room. In fact, this is possible even if space turns out not to

be infinite in size, though the reasons are complicated and have to do with the infinite

differentiability of the metric of spacetime...

But anyway, the event unfortunately known as the big bang was basically a time, long

ago, when space was much more squeezed together, and the observable universe, that is, everything

that we see from earth, was crammed into a very very small piece of space. Because the

ENTIRE early universe was dense and hot everywhere, spacetime was curved everywhere and this curvature

manifested itself as a rapid expansion of space throughout the universe. And although

people call this "the big bang", it wasn't just big, it was everywhere. And it wasn't

really an explosion - it was space stretching out. It's really quite unfortunate that "the

Everywhere Stretch" isn't nearly as catchy as "the Big Bang".

Which brings us to the "big bang singularity", which is an even horribler name because every

single word is misleading. I mean, "singularity" seems to imply something that happened at

a single point. Which isn't at all what it's referring to - it SHOULD be called "the part

of the Everywhere Stretch where we don't know what we're talking about." Basically, our

current physical models for the universe are unable to properly explain and predict what

was happening at the very very beginning when the universe was super SUPER scaled down.

But rather than call it the "time when we don't have a clue what was happening, ANYWHERE",

for some reason we call it a "singularity".

This ignorance, however, does conveniently answer the question What happened BEFORE the

big bang? Because it tells us the question isn't well defined - back when space was so

incredibly compressed and everything was ridiculously hot and dense, our mathematical models of

the universe break down SO MUCH that "time" doesn't even make sense. It's kind of like

how at the north pole, the concept of "north" breaks down - I mean, what's north of the

north pole? The only thing you can say is that everywhere on earth is south of the north

pole, or similarly everywhen in the universe is after... the beginning.

But once time began, whenever that was, space expanded incredibly quickly all throughout

the universe - for a little while. Then expansion slowed, the universe cooled, stuff happened,

and after a few billion years, here we are.

One thing we still DON'T know is why this Everywhere Stretching happened - that is,

why did the universe start off in such a funny, compressed state, and why did it follow the

seemingly arbitrary laws of physics that have governed its expansion and development ever

since?

For Georges Lemaître, this might be where God finally comes into the picture to explain

the things science can't. Except that experimental evidence doesn't actually rule out the possibility

that there may indeed be a time "before" the beginning, a previous age of the universe

that ended when space collapsed in on itself, getting quite compressed and dense and hot,

but not enough to mangle up our ideas of what time is. It would have then bounced back out,

stretching in a fashion similar to what we call the big bang, but without the "we don't

know what we're talking about" singularity part. So, physics may actually be nudging

us back to the view that the Universe is eternal and didn't begin after all. In which case

Professor Lemaître might have to rethink his interpretation of the words "in the beginning."