I believe the big bang is the event where every single bit of matter we see today came from. What I don't believe it is is that it is the absolute beginning of the universe as we know it. The reason I don't believe that it is the absolute beginning is because for the singularity to explode ,or even for the elements inside the singularity to collide with each, other there must laws dictating how the particles interact with each other and other things such as gravity and pressure. To say the laws are a consequence of the big bang is illogical. So they must have came before the big bang? Most people would say that they are universal constants and have always been but in the multiverse theory there are universes (infinite) that have different laws of physics. They are also very fine tuned (especially the mathematical constants). I'm not saying anything about intelligent design as that would be very unscientific. I also think that it would be impossible (today) to answer the laws of physics question because science observes and uses the laws of physics to answer questions.
The reason for pondering this is because I write lots of simulation programs. These programs are pretty much artificial universes in which laws are put in place. Although, that would point to some kind intelligent design (not a god or anything like that) if you are not willing to think outside of the box and outside of the current laws of physics. If I were to think outside of the box I would say that outside of our laws of physics anything and everything can happen. AKA things can come about from nothing, which again sounds impossible but that is because you can't make something from nothing within our laws of physics. But, to say that this is the answer to the problem would be unscientific due to there being not a single shred of evidence of anything like this happening.
Just to clarify, I'm not religious in anyway and am very open minded to ideas; Although, I will probably criticize the ideas but that is what science is all about
Also, I'm not a physicist so if I got anything wrong please tell me.