A conflict of realism and determinism

TYPETheor./Math. Physics Seminar
Speaker:Daniel Terno
Affiliation:Macquarie University, Australia
Location:Lewiner Seminar Room (412)
Abstract:Wave-particle duality, superposition and entanglement are among the most counterintuitive features of quantum theory. These puzzling quantum aspects clash with our classical intuition and are the main motivation behind the construction of hidden-variables (HV) theories.
With the development of quantum technologies we can now test experimentally the predictions of quantum theory vs. HV theories and, consequently, put strong restrictions on several key assumptions of HV theories. Here we study a quantum delayed-choice experiment and show that, in the absence of superluminal communication, realism (defined as a property of photons being either particles or waves, but not both) is incompatible with determinism.
This failure is internal to the model and is not based on the conflict with quantum mechanics. When confronted with the entanglement-assisted experiment our result holds for arbitrarily low entanglement and does not use Bell-type inequalities. We propose and discuss an experiment to test our conclusions.