[HPLovecraft]

Originally Posted by T@T

I didn't know that, seems every program I see they conclude the big bang started as an extremely hot and dense particle smaller than an atom that basicly blew up 13.7 billion years ago and expanded to what we see today.

I'm far from a scientist but my pea brain just can't except some of this.

Where did the dense particle come from?

How old was it before it popped?

If hubble can see a galaxy 13.7 billion L-years away surely the big bang didn't instantly create galaxys...don't they take billions of years to form themselfs? Hubble could be looking at a galaxy 13.7 L-years away that formed 20 billion years earlier.

I actually missed your post, whoops, and I think Ahsartus has already explained some of it.

The beginning of the universe wasn't a dense particle (I think you probably got this idea from Lemaitre, the Catholic priest that first came up with the idea of a "Big Bang," and proposed a kind of "superatom" made of an electron and a positron). Some scientists believe it was a singularity, some believe a fluctuation in a uniform inflaton field -- but -- no one will know for sure (or at least try to puzzle it out using science and mathematics) until a unified theory between quantum mechanics and general relativity is formed. The mathematics fail at that level at this point in time.

The Big Bang explains the evolution of the universe after whatever caused it to come into existence caused it to come into existence. Inflationary cosmology pushes this back some, and gives the bang a bang, but it still doesn't explain what brought the universe into existence in the first place. Inflationary cosmology explains how space expanded (the inflaton field -- a type of Higgs field -- got stuck on a peak in its potential energy bowl, expanded space in a manifestation of its negative pressure and thus repulsive gravity, and then created the first fundamental particles of the universe as it rolled down to a zero value), but doesn't explain why the universe was right for all that happen. The most common guess would be a statistical fluctuation, which wouldn't be such a big deal when you consider the low entropy of that stage of the early universe compared to if existence just popped into being now. But, really, that's just a guess at this time.

As for how old it was before the universe began, this might not even be a problem worth considering if time began when space inflated. If that is the case, the idea of "before" would be meaningless. There would be no before without time.

Hubble can't see all the way back to the beginning of the universe. Its successor, the James Web Space Telescope won't be able to either, though it will be able to peer back farther. The science of galaxy formation is tricky, and while scientists know many things about how it happens, there's a lot they don't. However, when they peer into space, they're able to see fairly uniform stages of galaxy formation. Like a house being built, they're able to look back and see it coming together. Of course, they can't look back all the way, and will never be able to look back to the very beginning of the universe, so there is always new loops being thrown their way, and it is possible that galaxy formation will be pushed back to have occurred at an earlier time, but that doesn't necessarily mean the age of the universe will need to be, too.