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Defense Intelligence Reference Document High-Frequency Gravitational Wave Communications

Defense Intelligence Agency · 57 pages · text from the file's own layer

This Defense Intelligence Reference Document was prepared by the Defense Intelligence Agency under its Advanced Aerospace Weapon System Applications (AAWSA) program, is dated 6 April 2010 and is part of a series of advanced technology reports produced in FY 2009. It reviews proposed laboratory generators and detectors of high-frequency gravitational waves for communications. It favors an infrared-excited molecules transmitter and the Li-Baker detector, estimating about 1.9 million bits per second over 7,000 km through the Earth. It also discusses timing standards and interplanetary navigation uses.

  • p. 3 …the FTS Devices ............................................. 30 3.4.1 Propagating Signals From Optical Lattice Clocks for Timing ................ 31…
  • p. 4 …Omni-Directional Nature of the HFGW Radiation Pattern ....................... 10 Figure 8. Predicted Relic GW Energy Density…
  • p. 5 …The Piezoelectric Approach to HFGW generation is best for the proof-of- concept test and the…
  • p. 6 …Antennas, cables, and phone lines would be things of the past. A timing standard alone, provided…
  • p. 8 …over the time interval !1t, s; that is, the jerk or shake of the two masses…
  • p. 9 …The usual difficulty with HFGWs generated by nuclear reactions is the small dimensions of their nuclear…
  • p. 22 …the initial momentum uncertainty, dt is the time of the future measurement, and m is the…
  • p. 23 …Eis the effective energy contained within the detector cavity summed over the detection averaging time, and…
  • p. 24 …The temporal quality factor in the Li-Baker detector arises from averaging the signal over time…
  • p. 28 …Another way to increase Q is to arbitrary increase sample times of the signal. This technique…
  • p. 29 …There is also a hidden integral here which occurs over the sample time, which is understood…
  • p. 30 …3.3 FREQUENCY AND TIME STANDARD The first application of HFGW to the distribution of frequency…
  • p. 31 …The arrival times of the received PPS signals could be compared via time difference of arrival…
  • p. 32 …The universal nature of the HFGW frequency and time standards are especially helpful. The following telecommunication…
  • p. 33 …the search space is reduced, speeding acquisition. • Ultra-fast acquisition allows more efficient TDMA, or Time…
  • p. 34 …For a 5 μsec acquire test time, the result is Tacq = 150 x 150 x 16…
  • p. 35 …At this precision one could measure the time delay caused by changing once centimeter in height…
  • p. 36 …the problem of mapping the positions of the Lagrangian points, which vary slightly over time. 3…
  • p. 38 …As prototypes show promise they could be transitioned to device development, the first time that industry…
  • p. 39 …For instance, if there were one GW source on Earth, and one GW source on the…
  • p. 41 …Nonlinearity improves the focusing process and h goes to one in finite time, producing a singularity…
  • p. 45 …and Stephenson, G.V. (2007), "The Value Estimation of an HFGW Frequency Time Standard for Telecommunications…
  • p. 46 …Thesis, The University of Birmingham, January. Kippenberg, T. J. and Vahala, K. J. (2008), "Cavity Optomechanics…
  • p. 49 …time of future measurement, s effective energy contained within the detector cavity summed over the detection…
  • p. 50 …The project plan and timing are described below under separate headings for each component of the…
  • p. 51 …coils that superimpose upon the constant applied magnetic field a time-varying component at low frequency…
  • p. 53 …photon events, and has very good time resolution. The disadvantage is its cost and complexity. This…
  • p. 55 …Cryogen-free (more accurately, the cryogen is completely enclosed and re-cycled each time the magnet…
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4.4 OTHER POSSIBLE HFGW APPLICATIONS
The most stunning advances in HFGW applications will probably not be in
communications, but in the remotely HFGW-generated nuclear fusion, HFGW propulsion
and HFGW surveillance. If an ultra-high-intensity HFGW flux impinges on a nucleus, it is
possible that it could initiate nuclear fusion at a remote location, or mass disruption.
Also it may be possible to create radioactive waste-free nuclear reactions and energy
reactions (Fontana, G. and Baker, R. M L, Jr. 2007). As they suggest: "At high
amplitudes, GR (Gravitational Radiation) is nonlinear, thus we might expect a departure
from geometric optics. Fortunately, the problem has been already theoretically
examined and the resulting effects are found to be advantageous. Nonlinearity
improves the focusing process and h goes to one in finite time, producing a singularity
"regardless" of the starting, non-focused amplitude of the impinging gravitational wave
(Corkill and Stewart, 1983; Ferrari, 1988a; Ferrari 1988b; Ferrari, Pendenza and
Veneziano, 1988; Veneziano, 1987; Szekeres, 1992). The effect of a 11h = 0.995 pulse
of HFGWs on the couple formed by a deuterium nucleus and its electron is the reduction
of their relative distance by a factor of 200. If this distance reduction is effective for a
few picoseconds, then the two nuclei of a deuterium molecule can fuse and give an He
atom plus energy, which is the usual nuclear-fusion process in a star."
HFGWs could theoretically be used for propulsion and control of the motion of objects
such as missiles, missile warheads, spacecraft, and asteroids, and remote control of
clouds of hazardous vapors. Gravitational field changes by one or more HFGW
generators could urge a spacecraft in a given direction, causing a lower static
gravitational field in front of a vehicle (it "falls" forward) and a higher one behind
(providing a "push"). The concept is that the mass essentially "rolls" down a "hill"
produced by the static g-field; that is, potential energy increase of a mass is provided
by the energetic HFGWs. The magnitude of the static g-field is proportional to the
square of the HFGW frequency (Landau and Lifshitz, 1975, section 108, page 349).
Specifically:
"Since it has definite energy, the gravitational wave is itself is the source of some
additional gravitational field (static g-field). Like the energy producing it, this field is a
second-order effect in the hik. But in the case of high-frequency gravitational waves the
effect is significantly strengthened: the fact that the pseudotensor t1k is quadratic in the
derivatives of the h;k introduces the large factor A· 2 . In such a case we may say that the
wave itself produces the background field (static g-field) on which it propagates. This
[static g] field is conveniently treated by carrying out the averaging described above
over regions of four-space with dimensions large compared to A. Such an averaging
smooths out the short-wave "ripple" and leaves the slowly varying background metric
(static g-field)." (Brackets and underline added for clarity and emphasis.)
Such an application must also await the future development of very high-intensity
HFGW generators.
A novel means of imaging or HFGW surveillance might be developed in future to
establish a system to allow for observing activities and materials in three dimensions,
within and below structures and within the Earth and its oceans. Gravitational waves,
including HFGWs, pass through most material with little or no attenuation; but although
they are not absorbed, their polarization (Li and Nan, 2009), phase velocity (causing
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Report, from the dia collection. The PDF is mirrored here; the original link is under it. 57 pages are in the text index: search them above, or from the library's search.