its like asking what is the sky blue!
there is no centralized authority in bitcoin because it is designed that way and it is supposed to be that way. meaning a decentralized or "a peer to peer digital cash" as the bitcoin original paper calls it. and people are interested in bitcoin, investing in it, and the price is rising because of this!
in other words being decentralized is one of the main aspects of bitcoin which gives it the power it has, otherwise we already have centralized currencies which we call fiat. if you want them then continue using the old systems that you know and use fiat.
thanks