All asteroids should have already been destroyed if the universe was billions of years old ( I don't know if this is some creationist invention though )
I don't see how this is a problem with the big bang model. Why? Our universe is roughly 14 billion years old. Our solar system, though, is like 4.5 billion years. All the asteriods in our solar system were created with the solar system.
And it's a pretty big claim to say that all should have been destroyed. The universe is a very big place. It's quite concievable that an asteroid would not collide with something, and even that collision would not necessarily destroy it (look at our asteroid belt, many many collisions, and they are still there).
A problem with the big bang is going to rest with the actual physics, I would think.
As to your limitation on discussing the singularity, I think that might be very difficult, seeing as how it's important with the Big Bang.
And good luck with keeping rob from posting about morality.
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