What Are White Holes?

But I might be wrong since I'm only 12, and trying to figure an answer to what white holes are...

Also the people in the other dimension would be just like us; where they know how white holes form but don't know what's on the other end like us

I feel like the concept of a white hole is simple it's just a reverse black hole that pushes things out word instead of pulling in; but since white holes probably don't exist, they might in another dimensio

Also the gravitation pull of a super massive black hole 12 billion times the size our sun must be very strong. Why doesn't such a gravitation force pull all objects close to it into it. It must have a gravitation pull of billions and billions of miles. And as time goes on and the black hole gets even larger, maybe all matter would stop expanding and then start moving towards this black hole? Yes, I am asking about the Big Crunch.

Has mathematician been able to predict at what size a super massive black hole might explode? And if a black hole exploded could this explosion be a "Big Bang"?

Check this out: <a href="http://www.space.com/30749-the-martian-faster-way-to-mars.html" rel="nofollow noopener" target="_blank">http://www.space.com/30749-the-martian-faster-way-to-mars.html</a>