Title: Shut Up and Calculate: The Many Worlds of Quantum Mechanics

Speaker: Prof. Surjeet Rajendran, Johns Hopkins University

Abstract: The usual presentation of the postulates of quantum mechanics in textbooks introduces a variety of ad-hoc axioms to describe the phenomena of measurement. These axioms make little logical sense even though they accurately describe the empirical phenomenology of measurement. In this note, I will show that these ad-hoc axioms are unnecessary. There is really only one axiom of quantum mechanics - namely the Schrodinger equation. By supplementing this equation with the assumption that the Hamiltonians that exist in the world are local, I will derive the phenomenology of measurement such as the collapse of the wave-function, the emergence of probability from the deterministic Schrodinger equation and the absence of measurements of macroscopic superpositions. Further, by observing that macroscopic bodies are in coherent (or other suitably localized) states, I will also show how the Born rule emerges from this description.