Obviously you mean guarantee by a central authority. That's not going to happen ever because bitcoin don't wants that to happen.
You see bitcoin with fiat currency standards thats why you can't understand basic things.
No. Thats one form of backing (dollar).
Gold/Silver have backing (inherent).
Bitcoin has NO backing.
Bitcoin has that other backing that you talk about. It's the massive value of it's network and the thousands of people's that are strengthen that network.