  However, satisfying the Lorentz transformations at the level of individual processes is not sufficient for compatibility with Minkowski spacetime; for the Lorentz transformations may also be satisfied at the level of individual processes in theories that postulate a preferred inertial reference frame (Bell 1976). Maudlin (1996, section 2) suggests that a theory is genuinely relativistic (both in spirit and letter) if it can be formulated without ascribing to spacetime any more, or different intrinsic structure than the relativistic  metrics.[35] The question of the compatibility of relativity with quantum mechanics may be presented as follows: Could a quantum theory that does not encounter the measurement problem be relativistic in that sense?  