Individuation in Quantum Mechanics and Space-Time

Gregg S. Jaeger

Chandralekha Singh

We discuss student difficulties in distinguishing between the physical space and Hilbert space and difficulties related to the Time‐independent Schroedinger equation and measurements in quantum mechanics. These difficulties were identified by administering written surveys and by conducting individual interviews with students.

Sebastián Fortín, Olímpia Lombardi

Abstract Despite the successful development of quantum chemistry, the deep breakdown between the conceptual basis of standard quantum mechanics and some implicit ontological assumptions of quantum chemistry is only rarely acknowledged. In fact, in the framework of standard quantum mechanics, quantum systems are not individual objects in the philosophical sense: they cannot be individualized by their positions in space and time and, as a consequence, they have no trajectories. By contrast, the basic magnitude in quantum chemistry is the electronic density, which is commonly interpreted in terms of the definite positions occupied by the individual electron in its motion around the nucleus. In the present paper, it will be argued that Bohmian Mechanics offers an ontological picture that is much closer to the quantum chemists’ way of conceiving their research field.

Wolfram Schommers

Tim Maudlin

Horton, G, Christopher Dewdney

We demonstrate how to construct a lorentz-invariant, hidden-variable interpretation of relativistic quantum mechanics based on particle trajectories. The covariant theory that we propose employs a multi-time formalism and a lorentz-invariant rule for the coordination of the space-time points on the individual particle trajectories. In this way we show that there is no contradiction between nonlocality and lorentz invariance in quantum mechanics. The approach is illustrated for relativistic bosons, using a simple model to discuss the individual non-locally correlated particle motion which ensues when the wavefunction is entangled. A simple example of measurement is described.