Can any binary problem be solved by a QUBO?

Question

As far as I know, if a computing problem can be solved by the quantum annealing approach, it also means the solution space should be binary, e.g., a vector that only contains either 0 and 1. Otherwise, there are no further conditions, correct? Since the rest to do is to transform the problem to a QUBO matrix, correct?

That means, if I am sure that the answer to my computing problem can be encoded in binary form and the problem can be presented in a QUBO matrix form, this implies that the problem can always be solved by quantum annealing approach.

Do I understand correctly? Thank you for your answer.

Answer 1

Any computing problem that can be solved on an ordinary classical computer can be solved by QUBO by using one of various transformation techniques, but this doesn't mean that it will be efficient to solve the problem using QUBO. Sometimes it's more efficient to solve the problem in a different way.