<Dl> <Dd> MWI response: Everett analysed branching using what we now call the "measurement basis". It is fundamental theorem of quantum theory that nothing measurable or empirical is changed by adopting a different basis . Everett was therefore free to choose whatever basis he liked . The measurement basis was simply the simplest basis in which to analyse the measurement process . </Dd> </Dl> <Dd> MWI response: Everett analysed branching using what we now call the "measurement basis". It is fundamental theorem of quantum theory that nothing measurable or empirical is changed by adopting a different basis . Everett was therefore free to choose whatever basis he liked . The measurement basis was simply the simplest basis in which to analyse the measurement process . </Dd> <P> We cannot be sure that the universe is a quantum multiverse until we have a theory of everything and, in particular, a successful theory of quantum gravity . If the final theory of everything is non-linear with respect to wavefunctions then many - worlds would be invalid . </P> <Dl> <Dd> <Dl> <Dd> MWI response: All accepted quantum theories of fundamental physics are linear with respect to the wavefunction . While quantum gravity or string theory may be non-linear in this respect there is no evidence to indicate this at the moment . </Dd> </Dl> </Dd> </Dl>

Ou think that everything in the world is relative