SETI-related: fast radio bursts

Recently, there has been some media coverage of a recent sample of fast radio bursts (FRBs) that are an unusual regular integer spacing apart, raising the possibility of intelligent life.

The original paper:

We have noted a potential discrete spacing in DM of FRBs. Identified steps are integer multiples of 187.5cm−3

In case this would hold, an extragalactic origin would seem unlikely, as high (random) DMs would be added by intergalactic dust. A more likely option could be a galactic source producing quantized chirped signals, but this seems most surprising. If both of these options could be excluded, only an artificial source (human or non-human) must be considered, particularly since most bursts have been observed in only one location (Parkes radio telescope). A re-assessment of man-made phenomena, such as perytons (Burke-Spolaor et al. 2011), would then be required. Failing some observational bias, the suggestive correlation with terrestrial time standards seems to nearly clinch the case for human association of these peculiar phenomena.

Usefully sceptical coverage by Gizmodo:

No matter how you slice it, eleven data points is a small sample set to draw any meaningful conclusions from. A handful of deviant observations could cause the entire pattern to unravel. And that’s exactly what seems to be happening. As Nadia Drake reports for National Geographic, newer observations, not included in the latest scientific report or other popular media articles, don’t fit:

“There are five fast radio bursts to be reported,” says Michael Kramer of Germany’s Max Planck Institute for Radioastronomy. “They do not fit the pattern.”

Instead of aliens, unexpected astrophysics, or even Earthly interference, the mysterious mathematical pattern is probably an artifact produced by a small sample size, Ransom says. When working with a limited amount of data – say, a population of 11 fast radio bursts – it’s easy to draw lines that connect the dots. Often, however, those lines disappear when more dots are added.

“My prediction is that this pattern will be washed out quite quickly once more fast radio bursts are found,” says West Virginia University’s Duncan Lorimer, who reported the first burst in 2007. “It’s a good example of how apparently significant results can be found in sparse data sets.”

Who here knows more about this?