Defense Intelligence Reference Document Quantum Tomography Of Negative Energy States In The Vacuum

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case of dielectric media. These particular cases will not be considered further since
there are technical subtleties involved that complicate the calculations and application
of the different approaches.
As a final note, negative energy can be created by a single moving reflecting
(conducting) surface (a.k.a. a moving mirror) via the dynamical Casimir effect. A
mirror moving with increasing acceleration generates a flux of negative energy that
emanates from its surface and flows out into the space ahead of the mirror [23, 52].
This is essentially the simple case of an infinite plane conductor undergoing acceleration
perpendicular to its surface. If the acceleration varies with time, the conductor will
generally emit or absorb photons (i.e., exchange energy with the vacuum), even
though it is neutral. This is an example of the well-known quantum phenomenon of
parametric excitation. The parameters of the quantum electromagnetic oscillators
(e.g., their frequency distribution function) change with time owing to the acceleration
of the mirror [53]. However, this effect is known to be exceedingly small, and it is not
the most effective way to produce negative energy for our purposes. We will not
consider this scheme any further.
QUANTUM OPTICAL HOMODYNE TOMOGRAPHY
Observing Negative Energy in the Lab
Negative energy should be observable in lab experiments. A generic, non-optical
scheme for detecting negative energy in experiments was recently reported by Davies
and Dttewill [54] who studied the response of switched particle detectors to static
negative energy densities and negative energy fluxes. Their model is based on a free
(massless) scalar field in flat 4-dimensional Minkowski spacetime and utilized a simple
generalization of the standard monopole detector, which is switched on and off to
concentrate the measurements on periods of isolated negative energy density (or
negative energy flux). The detector model includes an explicit switching factor whereby
five different switching functions (based on data windowing theory) are defined and
evaluated.
In order to isolate the effects of negative energy, a comparison is made for the
response of a detector switched on and off during a period of negative energy density
(or negative energy flux) and that switched on and off in the vacuum. The results shed
light on the response of matter ( detectors) to pulses of negative energy of finite
duration, and they showed that negative energy should have the effect of enhancing
de-excitation (i.e., induce cooling) of the detector. This is the opposite of our
experience with detectors that undergo excitation when encountering "normal" matter
or energy, and isolated detectors placed in a vacuum naturally cool due to the usual
thermodynamic reasons. But Davies and Ottewill point out that the enhanced cooling
effect they discovered cannot be used to draw a thermodynamic conclusion because
their modeling was restricted to first order in perturbation theory. It is not possible at
first order to determine whether the enhanced cooling effects are due to the small
violation of energy conservation expected in any process in which a general quantum
state collapses to an energy eigenstate, or whether they predict a systematic reduction
in the energy of the detector which has serious thermodynamic implications. However,
Davies and Ottewill point out that their results are model dependent and they found for
their standard monopole detector model that there is not always a simple relationship
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