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This Defense Intelligence Reference Document from the Defense Intelligence Agency, dated 6 April 2010, is one in a series of FY 2009 advanced technology reports produced under the Advanced Aerospace Weapon System Applications (AAWSA) program. It reviews the physics of zero-point field energy in the quantum vacuum and proposed schemes for extracting it, including the Casimir effect, Forward's vacuum-fluctuation battery, and resonant dielectric spheres. It notes that no practicable extraction technique has been demonstrated in the laboratory.
UNCLASSIFIED/ ,'1"1!11'- l!ll"l"ll!lllile lal!i& i;nn,~· QED Vacuum as a Mathematical "Placeholder" for Fluctuating Matter Fields The treatment of the QED vacuum as a fluctuating plenum with (formally) infinite energy density has caused some physicists to call into question the viability of the second-quantized QED formalism. Jaynes, for example, in considering the consequences for calculation of the Lamb shift of the 2s level of the hydrogen atom under the assumption of a much more modest electron Compton frequency cutoff(~ 1021 Hz), calculates a fluctuating power flow for the Poynting vector of 6 x 10 20 MW/cm 2 - comparable in every square centimeter to the total power output of the sun - and states that "real radiation of that intensity would do a little more than just shift the 2s level by 4 microvolts" (Reference 56). However, despite alternatives to the formalism of QED that have been suggested (more on this later), second-quantized QED cannot be lightly dismissed; and this is so even though the infinities that must be dealt with by such procedures as renormalization caused even one of its founders, Paul Dirac, to remark: "This is just not sensible mathematics. Sensible mathematics involves neglecting a quantity when it turns out to be small - not neglecting it because it is infinitely great and you do not want it" (Reference 57). A second argument that can be raised against using the QED formalism to further explore vacuum fluctuation physics is that, despite the magnitude of the energy density potentially associated with vacuum electromagnetic fluctuations, observation of the cosmological constant-a measure of net vacuum energy density-has a value that is only on the order of the average energy density of (ordinary+ dark) matter in the universe"" 10-9 J/m 3 (Reference 58, 59). This leads to what is often referred to as the 120 orders-of-magnitude problem, or "cosmological coincidence." In the mainstream view, rather than the QED value being discounted, the resolution of this problem is thought to lie in the domain of infinity (or divergent integral) cancellations, requiring instead an accounting for the fine-tuning requirements of such cancellations (Reference 60, 61). Again, the root cause of the difficulties that accompany second quantization of the vacuum field is that an unbounded plenum possesses an infinite number of degrees of freedom, each with its assigned ground-state fluctuation energy. In an attempt to circumvent the difficulties associated with an unbounded, second-quantized plenum, alternative approaches to QED have been explored in the literature in some detail, a few of which are discussed in Section V. A number of these alternative viewpoints interpret the second-quantized QED vacuum with its infinite degrees of freedom as simply an over-idealized mathematical placeholder for "real" fields that originate in matter fluctuations whose number of degrees of freedom is necessarily always limited. Nevertheless, though the alternative formalisms and associated interpretations differ significantly from the canonical approach, detailed calculations yield results identical to those generated by the second-quantized field formalism. As a result, even treated as a mathematical placeholder for matter fluctuation fields, at this point in our discussion the QED value must be taken seriously. The proposed corollary concerning the potentially significant conversion of QED vacuum energy to other forms is further evaluated in the sections that follow. 23 UNCLASSIFIED//FOll OFFlfalPk llili O.ik¥
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Report, from the dia collection. The PDF is mirrored here; the original link is above. 57 pages are in the text index: search them above, or from the library's search.