Proposal for Observing the Unruh Effect using Classical Electrodynamics.

Although the Unruh effect can be rigorously considered as well tested as free quantum field theory itself, it would be nice to provide experimental evidence of its existence. This is not easy because the linear acceleration needed to reach a temperature 1 K is of order 10^{20} m/s^{2}. Here, we propose a simple experiment reachable under present technology whose result may be directly interpreted in terms of the Unruh thermal bath. Instead of waiting for experimentalists to perform it, we use standard classical electrodynamics to anticipate its output and fulfill our goal.

Awaking the vacuum in relativistic stars.

Void of any inherent structure in classical physics, the vacuum has revealed to be incredibly crowded with all sorts of processes in relativistic quantum physics. Yet, its direct effects are usually so subtle that its structure remains almost as evasive as in classical physics. Here, in contrast, we report on the discovery of a novel effect according to which the vacuum is compelled to play an unexpected central role in an astrophysical context. We show that the formation of relativistic stars may lead the vacuum energy density of a quantum field to an exponential growth. The vacuum-driven evolution which would then follow may lead to unexpected implications for astrophysics, while the observation of stable neutron-star configurations may teach us much on the field content of our Universe.

Overspinning a nearly extreme charged black hole via a quantum tunneling process.

We examine a nearly extreme macroscopic Reissner-Nördstrom black hole in the context of semiclassical gravity. The absorption rate associated with the quantum tunneling process of scalar particles whereby this black hole can acquire enough angular momentum to violate the weak cosmic-censorship conjecture is shown to be nonzero.