Absolutely empty — that is how most of us envision the vacuum. Yet, in reality, it is filled with an energetic flickering: the quantum fluctuations. Experts are currently preparing a laser experiment intended to verify these vacuum fluctuations in a novel way, which could potentially provide clues to new laws in physics. A research team from the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) has developed a series of proposals designed to help conduct the experiment more effectively — thus increasing the chances of success. The team presents its findings in the scientific journal Physical Review D.
The physics world has long been aware that the vacuum is not entirely void but is filled with vacuum fluctuations — an ominous quantum flickering in time and space. Although it cannot be captured directly, its influence can be indirectly observed, for example, through changes in the electromagnetic fields of tiny particles.
However, it has not yet been possible to verify vacuum fluctuations without the presence of any particles. If this could be accomplished, one of the fundamental theories of physics, namely quantum electrodynamics (QED), would be proven in a hitherto untested area. Should such an experiment reveal deviations from the theory, however, it would suggest the existence of new, previously undiscovered particles.
The experiment intended to accomplish this is planned as part of the Helmholtz International Beamline for Extreme Fields (HIBEF), a research consortium led by the HZDR at the HED experimental station of the European XFEL in Hamburg, the largest X-ray laser in the world. The underlying principle is that an ultra-powerful laser fires short, intense flashes of light into an evacuated stainless steel chamber. The aim is to manipulate the vacuum fluctuations so that they, seemingly magically, change the polarization of an X-ray flash from the European XFEL, i.e., rotate its direction of oscillation.
“It would be like sliding a transparent plastic ruler…