Quantum mechanical particles tend to be in a 'superposition' of different locations at the same time. (a) Briefly describe what a measurement looking for the particle at location 'A' will find if a particle is in an equal superposition of occupying 2 locations labeled 'A' and 'B'. (b) Why is the superposition principle essential to allow particles to also behave as waves?

21st-century physicists tend to take a hard-line view that the mathematics of quantum mechanics do not require further interpretation, and one does not need to impose additional rules to simplify what occurs in a measurement. This has the consequence that there is no longer a singular 'result' following a measurement - every possible measurement outcome will occur, each within its own branch of a massively parallel universe. (c) How does this resemble or differ from the Copenhagen interpretation, as it is described in the book? (d) Why is it difficult to distinguish between this perspective and the Copenhagen interpretation?