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

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might work, it is necessary to characterize the physics of the ZPF and proposed energy
extraction techniques, and to evaluate their feasibility for application to space power
and propulsion systems. In what follows, the physics of the ZPF and the experimental
investigations being pursued to address the question of extracting energy from the
quantum vacuum are summarized.
III. Origin of Zero-Point Field Energy
ELEMENTS OF QED THEORY
The basis of the ZPF is typically attributed to the Heisenberg Uncertainty Principle.
According to this principle, A and B are any two conjugate observables that one is
interested in measuring, and they obey the commutation relation [A,B] = in. 4 Their
corresponding uncertainty relation is M~B 2'. n/2, where M is the variance (aka
uncertainty) of observable A and ~B is that of the conjugate observable B. This relation
states that if one measures observable A with very high precision (that is, its
uncertainty M is very small), then a simultaneous measurement of observable B will be
less precise (that is, its uncertainty ~Bis very large), and vice versa. In other words, it
is not possible to simultaneously measure two conjugate observable quantities with
infinite precision. This minimum uncertainty is not due to any correctable flaws in
measurement, but rather reflects the intrinsic fuzziness in the quantum nature of
energy and matter. Substantial theoretical and experimental work has shown that in
many quantum systems the limits to measurement precision is imposed by the
quantum vacuum ZPF embodied within the uncertainty principle. Nowadays one would
rather see the Heisenberg Uncertainty Principle as a necessary consequence, and
therefore, a derived result of the wave nature of quantum phenomena. The
uncertainties are just a consequence of the Fourier nature of conjugate pairs of
quantities (observables). For example, the two Fourier-wave-conjugates time and
frequency become the pair of quantum-particle conjugates time and energy and the
two Fourier-wave-conjugates displacement and wavenumber become the pair of
quantum-particle conjugates position and momentum. For more on this see, for
example, Reference 13.
Classically, electromagnetic radiation can be pictured as waves flowing through space at
the speed of light. The waves are not waves of anything substantive, but are in fact
ripples in the state of a field. These waves carry energy, and each wave has a specific
direction, frequency and polarization state. This is called a "propagating mode of the
electromagnetic field." A useful tool for modeling the propagating mode of the
electromagnetic field in quantum mechanics is the ideal quantum mechanical harmonic
oscillator: a hypothetical charged mass on a perfect spring oscillating back and forth
under the action of the spring's restoring force. The Heisenberg Uncertainty Principle
dictates that a quantized harmonic oscillator (aka a photon state) can never come
entirely to rest, since that would be a state of exactly zero energy, which is forbidden
by the commutation relation outlined above. Instead, every mode of the field has hw/2
as its average minimum energy in the vacuum. 5 (This is a small amount of energy, but
the number of modes is enormous, and indeed increases as the square of the
frequency. The product of this minuscule energy per mode, multiplied by the huge
spatial density of modes, yields a very high theoretical energy density per unit volume.)
4 i is the unit complex number. n is Planck's reduced constant, 1.055 x 10-34 J-s.
5 w is the mode or photon frequency and nw is the energy of a single mode or photon.
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