What problems for example?

Decentralization problem will be sorted in RPB by mining 

Yes, but this is only a side effect. When money appeared - there was the problem of corruption. Everything has its drawbacks.

I wonder how Republia is going to solve the problem of 51 attacks?

Thank you for your question. Since Republia operates using the algorithm Delegated Proof-of-Authority (DPoA) + BFT (Byzantine Fault Tolerance) the network is protected from such a threat as an attack of 51%, because the modernization of the subsystems is influenced equally by all users, and not by those with more capacities at their disposal. When voting each participant uses his unique RepubliaID, which guarantees only one vote from one user within a voting.

It's something like your unique number, as I understand it.

maybe this is one of the reasons

I correctly understood that I can only vote if I have this Republia id?

I`m not sure about RPB...what is the best cryptocurrency in the market?