Einstein on Particles, Fields, and the Quantum Theory

Res Jost

Yasunari Kurita, Michikazu Kobayashi, Hideki Ishihara +1 more

We formulate particle-creation phenomena in Bose-Einstein condensates in terms of conserving gapless mean-field theory for weakly interacting Bose gases. The particle-creation spectrum is calculated by rediagonalizing the Bogoliubov--de Gennes (BdG) Hamiltonian in mean-field theory. The conservation implies that quasiparticle creation is accompanied by quantum back reaction to the condensates. Particle creation in this mean-field theory is found to be equivalent to that in quantum field theory (QFT) in curved space-time. An expression is obtained for an effective metric affected by quantum back reaction. The formula for the particle-creation spectrum obtained in terms of QFT in curved space-time is shown to be the same as that given by rediagonalizing the BdG Hamiltonian.

Seiya Abiko

Max Jammer

Paweł Caban, Jakub Rembieliński

We calculate correlation function in the Einstein-Podolsky-Rosen type of experiment with massive relativistic Dirac particles in the framework of the quantum field theory formalism. We perform our calculations for states which are physically interesting and transform covariantly under the full Lorentz group action---i.e., for pseudoscalar and vector states.