[Benzenelover]

What was before existence? How did it start? What do you think the first second was like? How could there have been anything before existence if existence didn't exist back then? 

[vmelkon]

The current theory is that everything has always existed. Everything in the universe was at a single point and the 4 forces were one. Outside the point, there was no existence. The point expanded (big bang), and the forces separate (gravity, electro-magnetic, weak force, strong force).
You might also want to read about dark matter and dark energy.

I don't know of any theories about things coming out of non-existence.

[Borek]

The current theory is that everything has always existed.

Do you have any reference for that?

[vmelkon]

The current theory is that everything has always existed.

Do you have any reference for that?

You can do a search on the Big Bang theory and you'll find different models. Some models describe the beginning as time = 0 and that before that, we(they) don't know the state of the universe.
Some models talk about a cyclic event of Big Crunch and Big Bang that runs continuously.
http://arxiv.org/abs/hep-th/0205259

I haven't yet seen the model that describes the Big Bang singularity coming out of non-existence.

However, the Big Bang singularity coming out of non-existence is often mentioned by Christians since logically (their logic), you need a God.

[Borek]

Some models describe the beginning as time = 0 and that before that, we(they) don't know the state of the universe.

I haven't yet seen the model that describes the Big Bang singularity coming out of non-existence.

OK, perhaps that's where the confusion comes from - you assume "we don't know the state of Universe before Big Bang" to mean "there was something, we just don't know what". I assume it means "there either was something, or not".

From what I understand both approaches are purely speculative.

[vmelkon]

I assume it means "there either was something, or not".

Why do you assume that? (1)Are cosmologies saying before time = 0, we don't know that the universe existed or not?
(2) Or are they saying "we don't know the state of the universe"?
(3) Or are they saying "we don't know the state of existence of the universe"?

Are (1), (2) and (3) the same?

In terms of the universe coming out of non-existence (the subject of this thread), I'm just saying that no one is pushing this one forward.
Is it the OP point of view? Is it some theory from someone?

[Borek]

As far as I know cosmologies say "we have no idea what was before t=0". You wrote

The current theory is that everything has always existed.

which is quite a bold statement in this context. There is a huge difference between "we have no idea" and "we know it existed".

[juanrga]

What was before existence? How did it start? What do you think the first second was like? How could there have been anything before existence if existence didn't exist back then? 

Time?
From nothing except time?
The first second is covered by the Lepton epoch of the standard model of cosmology
Time exists in time?

[hirdscemicals]

why does it even matter! we are never going to figure this out and if we did we would still question it lol

[vmelkon]

why does it even matter! we are never going to figure this out and if we did we would still question it lol

It matters to some people even if you end up with an explanation that is not guaranteed to be exact. It is better to work on the problem instead of not doing anything at all.

[Dan]

Funny, I just saw a BBC documentary bout this. It is an episode of Horizon: 2010-2011 episode 3.

If you are in the UK you can watch it for free this week here (and if not perhaps you can find another source):

http://www.bbc.co.uk/iplayer/episode/b00vdkmj/Horizon_20102011_What_Happened_Before_the_Big_Bang/