IQI Weekly Seminar

  It is often assumed that the clash between Quantum Mechanics (QM) and  General Relativity (GR) happens only as one approaches the Planck  energy. I will show through simple thought experiments that there is  also a severe conflict at laboratory energy scales. I will then argue  that the only reasonable way to fix this is in a  correlated  worldline  theory wherein gravity creates correlations between  different Feynman paths for the SAME PARTICLE (or same Quantum  Field). The basic structure of this theory is explained, and the  modifications it implies for our ideas about spacetime.      For laboratory tests one only requires the low-energy version of this  theory, and controlled calculations can be done with no adjustable  parameters. I describe how such calculations can be done, and then  what sort of effects they predict for  2-path  experiments. The  deviations from QM will be hard to see, since gravity is a weak force    but they are by no means beyond current experimental techniques.