From condensed matter to quantum gravity: the gravitational Casimir-Polder force

by Johanna Karouby (Tufts University)

Monday 9 Jan 2017, 14:15 → 15:15 Europe/Berlin

Main-2-313 (MPI Meeting rooms)

Since general relativity is a consistent low energy effective field theory, it is possible to compute quantum corrections to classical forces. I will present the computation of a quantum correction to the gravitational potential between a pair of polarizable objects. I will show the case of two distant bodies and compute a quantum force from their induced quadrupole moments due to two graviton exchange. The effect is in close analogy to the Casimir-Polder and London-van der Waals forces between a pair of atoms from their induced dipole moments due to two photon exchange. The new effect is computed from the shift in vacuum energy of metric fluctuations due to the polarizability of the objects. I will present the computation for the potential energy at arbitrary distances compared to the wavelengths in the system, including the far and near regimes. In the far distance, or retarded, regime, the potential energy takes on a particularly simple form. Finally, I will provide estimates of this effect when applied to astrophysical objects such as neutron stars.