Conjectured properties of interstellar communication signals

Establish whether interstellar communication signals satisfy the following seven conjectured properties: (1) high information capacity; (2) energy efficiency; (3) occupation of a wide bandwidth; (4) measurements approaching those of Additive White Gaussian Noise (AWGN); (5) exceptional transmission of high Signal-to-Noise Ratio (SNR) narrow-bandwidth pulse pair components that are readily discoverable in random noise; (6) minimal interference with known and likely communication systems; and (7) repetition at celestial pointing directions during long-duration experiments.

Background

The paper investigates methods to detect extraterrestrial communication signals using a two-element radio interferometer, focusing on narrow-band At=0, Af pulse pairs and differential angle-of-arrival measurements. To frame expectations about detectable technosignatures, the authors explicitly list several "salient conjectures" about the properties intentional interstellar transmitters might exhibit.

These conjectures guide the experimental design and interpretation of observations, including assumptions about signal capacity, efficiency, spectral characteristics, similarity to AWGN, discoverability via narrow-band pulse pairs, non-interference with terrestrial systems, and celestial repetition. Confirming or refuting these conjectured properties is central to assessing the nature of the observed anomalies and informing subsequent hypothesis testing.