AAWSAP DIRD, The Space Communication Implications of Quantum Entanglement and Nonlocality, March 2010

This Defense Intelligence Reference Document, dated 30 March 2010, was prepared by the Defense Intelligence Agency's Defense Warning Office under its Advanced Aerospace Weapon System Applications Program. It reviews quantum entanglement, nonlocality and EPR experiments, and asks whether nonlocal quantum effects could carry observer-to-observer signals faster than light. The paper describes proposed experiments and an example of real-time Earth control of a Mars rover. It concludes that there is no compelling answer yet and that experimental tests are needed.

From the source:Release of 2026-09-18 Incident: 3/30/10, Las Vegas, Nevada. Released with redactions. This document is a Defense Intelligence Reference Document (DIRD), a technical reference format used by the Defense Intelligence Agency (DIA) to capture baseline knowledge on a specific topic for later analytic use. DIRDs are best understood as reference and synthesis products rather than as original research. It is one of 38 DIRDs produced under the Advanced Aerospace Weapon System Applications Program (AAWSAP) between 2009 and 2011. Because AAWSAP’s scope permitted a broad range of supporting topics, not every DIRD in the series directly concerns aerospace systems or future threat assessment. The following summary reflects the DIRD’s scope and framing at the time of writing and should not be read as implying current validation of the concepts discussed. This DIRD reviews quantum entanglement and nonlocality with a focus on whether those phenomena might be usable as a means of faster-than-light communication between observers, especially for real-time space operations over interplanetary distances. The report surveys the relevant quantum experiments and no-signal theorems, then examines proposed communication schemes based mainly on momentum-entangled photons, including scenarios involving superluminal and retro-causal signaling. However, it repeatedly acknowledges that the central question remains unresolved experimentally, and it gives substantial attention to the coherence-versus-entanglement tradeoff and other features of standard quantum mechanics that may prevent usable signaling even if non-local correlations are experimentally validated. Overall, the document is an exploratory analysis of whether quantum nonlocality could conceivably support a practical communications application rather than a demonstration of prospective utility.

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time standing wave (w•) between the locations (for example, a photon source and a
photon detector). After an initial exchange of offer and confirmation waves, a particular
transaction is selected probabilistically from all that are possible, based on the \Jf\/1*
values of the alternatives. The offer/confirmation exchange continues until all the
conserved quantities (energy, momentum, angular momentum, and so forth) have
been transferred.
For the nonlocal communication test system described above, we will consider two
cases:
• Case 1: The switch is positioned so that each fiber from the slits is routed to one
detector, producing a "which-way" measurement of the slit through which the VLP
photon passed. In this case, the HLP photon as detected by the camera should have
a recorded position that falls on a broad single-slit-diffraction-pattern distribution,
(not a two-slit interference pattern).
• Case 2: The switch is positioned so that light from the two fibers is combined before
detection. Therefore, the detection produces no information on the path of VLP
photon, which could have passed through either slit. In this case, the HLP photon
detected by the camera should be in a position that falls on a two-slit interference
pattern distribution.
Figure 8 shows the transaction that forms for the nonlocal communication test system
in the Case 1 configuration. Here, as in the Ghost Interference experiment, we have
treated the nonlinear crystal source of entangled pairs as an effective "reflector" and
have represented the rays with straight-through paths to "unfold" the system,
duplicating the lens for each photon and representing the system as two-lens optical
imaging, with nearly parallel rays between the two lenses. Slit systems S1 and S2 are
located one focal length f away from the lenses. The left-going photon is assumed to
arrive at the upper slit of S2 and to be detected by the upper detector (circled). The
momentum-entangled right-going photon must then go to S1, which is the optical
image of S2, and be diffracted by the slit and detected by the camera. If Figure 8 were
vertically inverted, it would provide a similar diagram for the equally probable arrival of
the left-going photon at the lower slit of S2 and detection by the lower detector. The
three stages of transaction formation are shown.
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