AAWSAP DIRD, Concepts for Extracting Energy from the Quantum Vacuum, April 2010

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vacuum and its related spacetime physics (for example, "emergent" spacetime/gravity
theories (Reference 109-111)), New materials or combinations of materials, such as
condensed matter (superconductors), semiconductors or metamaterials, would also be
an important game changer because of the unique ways that quantum fields would
interact with them to produce phenomena of interest.
In going forward to the potential demonstration of continuous energy extraction from
the vacuum, one should consider the following additional action items for further R&D:
•
The quantum vacuum electromagnetic effects outlined in Section IV were computed
to scale with Planck's constant and are therefore very small. In order to have a
practical device based on quantum vacuum properties, it would be preferable that
the vacuum effects the scale, meaning that the effects are essentially independent
of Plank's constant and consequently may be much larger . By itself this requirement
does not guarantee a large enough magnitude, but it certainly helps.
Electromagnetic Casimir effects are typically small and difficult to measure. In fact,
measurements have only been made for simple geometries such as the parallel
plate or the sphere-plate geometries. This fact raises a question: Is it possible to
amplify these effects and bring them into a useful range? This is certainly one of the
challenges of vacuum engineering. The experiment described in Section IV could
address this question.
•
Experiments are needed to explore some of the issues that are beyond the present
computational ability of QED; for example, the effect of complex geometries on
vacuum forces, or the effect of interacting or externally applied fields or dense,
moving nuclear matter on the quantum vacuum. Is it possible to make a stable
vacuum field that has a large variation in energy density? Can energy density
gradients be found on a length scale that is useful for technological applications?
One needs to greatly increase our knowledge of the quantum vacuum. The
development of a very sensitive small probe that provides a frequency
decomposition of the local vacuum energy density would very useful.
-
A first step in this direction was recently proposed by Marecki (Reference 112)
who generalized the analysis of the output of balanced homodyne detectors
(BHDs). The most important feature of these devices is their ability to quantify
the quantum vacuum fluctuations of the electric field because the output of BHDs
provides information on the one- and two-point functions of arbitrary states of
quantum fields. Marecki computed the two-point function and the associated
spectral density for the ground state of the quantum electric field in Casimir
geometries, and predicts a position- and frequency-dependent pattern of BHD
responses if a device of this type is placed inside a Casimir cavity. The proposed
device allows for the direct detection of quantum vacuum fluctuations and
provides a spatial mapping of the vacuum energy contained inside the cavity.
This offers a potential new characterization of ground states in Casimir
geometries, which would provide an understanding of the vacuum energy
densities present in some regions in these geometries.
•
From the status of current research in Casimir forces, it is clear that one is at the
cusp of describing the properties of the quantum vacuum for real systems with real
material properties. For example, there is no general agreement regarding the
calculations of static vacuum forces for geometries other than infinite parallel plates
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