Improspectives

Title: Gravity’s Kiss

Author: Harry Collins

Publisher: MIT Press

Copyright: 2017

ISBN13: 978-0-262-34003-8

Length: 416

Price: $29.95

I received a promotional copy of this book from the publisher.

Albert Einstein predicted gravitational waves as part of his theory of general relativity, with the caveat that the waves would be so weak they would be almost impossible to detect. Harry Collins, Distinguished Research Professor of Sociology and Director of the Centre for the Study of Knowledge, Expertise, and Science at Cardiff University, has closely observed gravitational wave science and its practitioners since 1972. In Gravity’s Kiss, he documents the first detection of gravitational waves and comments on the process from the complementary perspectives of sociology and physical science.

Years in the Making

Gravity’s Kiss starts by describing the initial mention of what turned out to be the first detection of gravitational waves. The Event, as it was soon known, occurred on September 14, 2015. Collins was at home, scanning through the subject lines of emails from the gravitational wave community, when he noticed a subject line mentioning an interesting occurrence during an engineering run of two new detectors. The devices were in Washington state and Texas, far enough apart that their readings could be compared, adjusted for the time to traverse the distance between the detectors, and examined for anomalies or glitches that could indicate an instrument fault or statistical coincidence that would invalidate the observation.

Collins’ method is to observe and report on science as it happens, so this message was his signal to more closely observe the process from his vantage as a trusted colleague with whom many practitioners willingly shared information. The author notes that, with one exception, he was the longest-tenured member of the gravitational wave community. He had observed years of work when everyone knew the odds of detection were vanishingly remote because their tools weren’t sensitive enough yet and been part of conversations when teams thought perhaps they had detected gravitational waves. (They hadn’t. The signal was a “blind injection” inserted by project managers to rehearse the procedures to be followed after a real detection.)

Secrets and Methods

Part of the ritual of science demands that experimenters maintain a measure of distance and detachment from their subject. As such, even knowledge of whether The Event came from real observations or had been injected into the data stream was kept secret from the researchers until it was time to “open the box” and determine whether the signal was real or the result of a glitch or blind injection. After each party to the analysis described their work, the team agreed all necessary due diligence was done, the seals on a few files were broken and the data compared to the signal. As it turned out, the signal was loud, clear, and free from mechanical glitches. Collins reports that the gravitational wave community celebrated the unveiling and turned almost immediately to the tasks of refining their analysis and writing the paper that would present their result to the world.

The paper, which everyone realized would be a landmark of the physics literature, brought the social side of science to the fore. Collins highlights two aspects of the paper writing and continuing analysis process that, in his opinion, hampered the community: secrecy and what he calls “relentless professionalism”. Not wanting to have their thunder stolen by scientists who were not part of the group, the consortium prohibited members from sharing anything about the detection with outsiders. While spouses and partners could be told, no one else was to know. This secrecy caused significant stresses within the group, particuarly as the analysis and writing process dragged on. Over the five months from the initial detection on September 14, 2015 to the press conference on February 11, 2016, the need to avoid disclosure strained relationships with colleagues and family even as bits of information leaked out. One rumor analyst was even able to piece together enough information from canceled conference attendance and similar tidbits to correctly predict the press conference’s date.

The process also suffered from “relentless professionalism”, where members asked increasingly fine-pointed questions regarding method, methodology, and results. The quest for statistical significance to claim a discovery, which in the physical sciences is measured by a severe five-sigma criterion, and the words used to describe a result take on deep meanings within the community. Collins describes the lengthy and occasionally fraught process with the eye of an experienced observer and with enough knowledge of the subject matter to comment on both the content of the paper and how it came to be. In practice, scientific endeavor is far from the detached process is often claims to be. Deciding whether to use the term “direct detection” in the paper’s title comes down to not wanting to hurt the feelings of previous researchers who, though not part of the consortium, are well-regarded and could lay claim to initial detection under certain interpretations of their work.

Conclusion

Collins’ contemporaenous narrative provides an enjoyable and relatable read. The first two-thirds of the book describe the process leading from initial detection to just after the paper was released, while the last third provides sociological context to flesh out his approach, observations, and recommendations. While he doesn’t shy away from wondering at the complexity of the detection apparatus and analytical techniques, his descriptions are delightfully free of hyperbole and treat the protagonists as good people doing the best they can to ensure their results are correct and share them appropriately. Gravity’s Kiss is the story of a monumental success brought about by a team of able researchers. Harry Collins was ideally positioned to relate the tale and made the most of his opportunity. Highly recommended.