when they say "13.7bn" years they talk about our known universe from the bing bang until now .. there is no need to talk about "before" the bing bang..nobody knows what was before the big bang as a fact. so yes.universe is infinite so is the age of the universe.

there was and is and will be always something.

See my other comment in response to binary solo, about the fact that there's indeed ongoing work on the foundations of QM.

I wanted to make clear one fact: our intuitive idea of a chain of causation comes from observation of macroscopic events. Masses and inertia and forces being needed to cause acceleration in linearly moving objects above all.

QM provides a layer under that, and a very different one. It's a world of probability functions, superimposed states and EPR paradoxes. Through mechanisms that are only partially understood, and somehow connected with the so called quantum measure problem, this layer averages out to macroscopic phenomena that are very well described by classical mechanics -obviously, since we knew it was a good theory in a great breadth of applications. It averages out to a world where the chain of causation is evident.

Now the problem is that we can't just assume that some axioms we inferred from classical mechanics have an absolute validity.

We don't observe, in the averaged out macroscopic world, a superposition of elephants. But we do observe superpositions of microscopic atomic states in QM.

We don't observe action-at-a-distance in the macroscopic world, but Aspect's experiment proved that there's something like that (thought not violating general realtivity) at the level of QM. And the invalidated local hidden variable theories that solve the action-at-distance problem are not too dissimilar from saying "maybe there's a cause, but we still can't see it"

Now, it could be that we're still missing microscopic causes for the collapse of a quantum superposition, or a whole new layer under QM, but it might as well be that our intuition only brings us so far, and that in QM the world actually -simply- works differently. Right now, QM works very well numerically and it doesn't appear to need such an axiom.

You know that the reason it's called science fiction is because it is inspired by science, and not the other way around.

Simple answer: Nobody knows whatsoever how old the Universe is or exactly how it started. There's some theories out there that could be right but no one actually knows.

A good chunk of "science" is like that. Just endless theories without definitive answers.

god did it 6000 years ago

That's all that God is? Nearly all interpretations of God assign more characteristics than those two. There's also the God having consciousness which is present in nearly every interpretation, and many religions have very specific characteristics too, like being all-loving, having a plan for humanity, designing humanity in his "image", etc.

A few objections to your post:

(A) You base your reasoning on the fact that everything needs a cause to come to existence. This "law" has only been observed in our universe. How do you know this law applies outside of our universe and/or before the existence of our universe? In fact, it's pretty much gauranteed that this principle doesn't exist outside of our universe. Even if you believe in God, you believe the principle of cause and effect doesn't exist outside of our universe since God has existed forever. In any theory, when you go back far enough, eventually you reach a point where something just "happened", or you'll discover that something always existed. 

(B) Let's assume our universe does need a cause. The only necessary characteristic of that cause would be to have more power than our universe (and even this is kind of shaky, but I'll assume it for the sake of the argument). It wouldn't need to be conscious or loving or even intelligent. These are just unjustified assumptions. Therefore, the theory that the universe had an unknown very powerful cause (with no further assumptions on its characteristics) is more likely than the God "theory" which brings many unjustified assumptions such as the cause having consciousness, existing for an eternity, being all-loving, etc. 

(C) Please explain why the God theory is more satisfactory than the multiverse theory and explain why the multiverse theory is ridiculous. 

Watch this and you'll hopefully get it ;)

The key point here is that only observed phenomena follow the principle of cause and effect (i.e. nothing outside of our universe). We have no way of knowing if this prinicple is in effect outside of our universe. 

In fact, it's pretty much gauranteed that this principle doesn't exist outside of our universe. Even if you believe in God, you believe the principle of cause and effect doesn't exist outside of our universe. In any theory, when you go back far enough, eventually you reach a point where something just "happened", or you'll discovered that something always existed. Neither of which match what we've observed in our universe.

Oh yes.

This clearly explains why the mass of the Higgs Boson means that everything will be destroyed by an alternate universe.

If  anyone actually answered his question they are probably god.