Reading through the paper in (3) above. If I understand the text on page 26 correctly, you predict that quantum computers will not be more efficient than classical computers:
"The class of problems that can be solved efficiently by quantum computers should be identical to the class of problems that can be solved efficiently by classical computers: More precisely, we predict in this appropriately coarse-grained case that P=BQP, where P and BQP denote the complexity classes of polynomial time and bounded error quantum polynomial time, respectively."
And:
"In other words, in order to maintain a causal invariant representation, the observer must perform a sufficient level of coarse-graining to ensure that any apparent advantage obtained through the use of a quantum computer over a classical one is effectively lost."
Am I missing something fundamental (most probably)? Are you predicting that quantum computers will not be able to, for example, factor RSA keys much faster than todays non-quantum machines?
"The class of problems that can be solved efficiently by quantum computers should be identical to the class of problems that can be solved efficiently by classical computers: More precisely, we predict in this appropriately coarse-grained case that P=BQP, where P and BQP denote the complexity classes of polynomial time and bounded error quantum polynomial time, respectively."
And:
"In other words, in order to maintain a causal invariant representation, the observer must perform a sufficient level of coarse-graining to ensure that any apparent advantage obtained through the use of a quantum computer over a classical one is effectively lost."
Am I missing something fundamental (most probably)? Are you predicting that quantum computers will not be able to, for example, factor RSA keys much faster than todays non-quantum machines?