awww, ya did.

Hmm. Solid is the right word, and what you say seems reasonable.

 

What about if you could somehow open a gateway into a black hole....

 

Well, if OP is drawn to a black hole (which I'm not sure about, it isn't drawn to the ground either. But light also seems not to be after all...), then the gateway would immediately disappear. If not, you have a problem, because it would draw in earth and you until you died, and the gateway disappeared.