"The thing we call gravity" is a small attraction between two or more objects, all objects have there own gravity, but with a bigger mass comes a bigger gravity force. For example, if two large boats are left still in the sea, they will slowly drift together, this is not magic, it is GRAVITY! Another example, what is a black hole? A black whole was once a VERY large object, a sun, to be precise, which when lost stability due to lack of fuel imploded in on itself, literally pulling itself to to a very small size, many times what it once was, but what does this have to do with gravity? Well, because it still has the same mass (but at a much smaller size) it's gravity is much more focused, so much so that not even light can escape it. THAT is gravity.
Also, the idea that the Earth is hollow? ... Even thinking that idea is an insult to the intelligence of the human race, i'm pretty laid back in letting people believe what they like, but the Earth being hollow? That just makes no sense at all, for example, have you heard of solar wind? No? Well, solar wind is "flares" which come from the sun, that without an atmosphere and a magnetic field we would be like mars, a planet barren and destroyed. So what makes the magnetic field? Iron. And a hell of a lot of it. More than we can ever have here on the surface, so where else could it be? Yes, that's right, the only place left for it is the core.
There are many other ways to prove the existence of a core to the Earth, such as: When you mine so far down, it gets hot, it gets hot because of the molten rock the people mine close to. And: When a volcano erupts where does the magma come from? Or how about: If the Earth is hollow, wouldn't it just collapse in on itself? Or even: If the Earth was hollow, it would spin around the sun at a different rate, meaning we would be either flung into space or sucked into the sun. And also: What about the numerous meteors that have hurtled into Earth, like the one that killed the dinosaurs, wouldn't they have punched through the surface? And last but not least: The Earth was formed by molten rock grouping together so isn't it impossible that the Earth was formed hollow?
Ha, that's it, my argument. Have fun trying to disprove my facts and convince others of your rubbish. Hmm, who knew a 16yr old could know so much, eh? Well, that's what T.V. does to ya!
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