The Origins Podcast with Lawrence Krauss

Searching for Aliens. The Wrong Way? A dialogue with John Gertz

The Origins Podcast with Lawrence Krauss

Summary

Lawrence Krauss engages in a thought-provoking discussion with John Gertz, former chairman of the SETI Foundation and author of "Reinventing SETI." Gertz challenges the traditional methods of searching for extraterrestrial intelligence, arguing that the current approach, which relies heavily on listening for signals from stars, is fundamentally flawed. He posits that the search for extraterrestrial life should focus on more practical strategies, such as sending robotic probes to explore our solar system and beyond, rather than expecting to receive signals from distant civilizations.

Gertz emphasizes the limitations of the Drake Equation, which attempts to estimate the number of communicative civilizations in the galaxy. He argues that many of its parameters are based on assumptions that may not hold true, such as the idea that intelligent life will develop in similar ways across different planets. Instead, he suggests that advanced civilizations may choose to remain silent or hidden, and that the best strategy for humanity is to prepare for potential contact by developing a robust framework for communication and understanding.

The conversation delves into the implications of sending signals into space and the risks associated with revealing our presence to potentially hostile extraterrestrial civilizations. Gertz advocates for a cautious approach, urging humanity to consider the consequences of its actions in the search for extraterrestrial life. Ultimately, the discussion highlights the need for a reevaluation of SETI's goals and methods, encouraging a more innovative and thoughtful approach to understanding our place in the universe.

Show Notes

John Gertz is a Renaissance Man. One might think that the President of Zorro Productions might be the last person to talk with about the Search for Extraterrestrial Intelligence (SETI), and the last person to chair SETI’s governing board. But as is clear from our discussion, and from the material in his recent book, Reinventing SETI, John has not only mastered all of the relevant technical issues, he has thought deeply about the motivation for SETI, and the likelihood of its success. Treating the issue as a businessman rather than a scientist, he has tried to anticipate what signals other civilizations might send, and what we might listen for. He also takes a realistic view of what we might actually be able to detect. The net result of our conversations is that the prospects are not good for detecting anything out there. Distant aliens are likely not broadcasting in a way we could be sensitive to. And as he points out, we should probably do the same. His great hope is that alien civilizations have instead installed probes in other solar systems, including ours. However, this possibility too, as I emphasized with him, is also rife with difficulties. I have thought a lot about SETI since I wrote The Physics of Star Trek. I don’t think anyone has affected my thinking on the issue since then more than John. I was pessimistic before. Now I think the whole effort is probably misguided. Though, if someone other than the government is willing to pay for it, what the heck. As I often tell experimentalists. Do what you can do, no matter what us theorists say. We may be wrong. I hope you find our discussion as informative and provocative as I did. I will be interested to hear if it changes your perspective on SETI as well. As always, an ad-free video version of this podcast is also available to paid Critical Mass subscribers. Your subscriptions support the non-profit Origins Project Foundation, which produces the podcast. The audio version is available free on the Critical Mass site and on all podcast sites, and the video version will also be available on the Origins Project YouTube.

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More from The Origins Podcast with Lawrence Krauss

Oct 19, 2026

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Sep 23, 2026

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Aug 18, 2026

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Aug 3, 2026

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Jul 29, 2026

I remember when my friend, journalist Claire Berlinski, first contacted me about a tragic situation regarding a family trapped in Afghanistan after the Taliban takeover. She knew that I had helped a young girl interested in physics escape to the US to study years earlier and hoped that I might assist in this case. If ever one imagined a family appropriate to bring to safety, this would be the one. The mother was a women’s rights lawyer before the takeover, and the husband worked for a French firm. The Taliban had broken into the Bar Association Office and found records of lawyers, who were being sought for arrest. One older son, and five young daughters in danger of being married off if they were discovered. Their original escape plan was foiled when the airport was bombed just before their planned departure. Because Claire lives in Frances the older boy had reached out to her for help, and she sent out a call to her followers to provide financial assistance to help the family. Claire contacted me because she knew I now lived in Canada, which has a well-established refugee program. In spite of this, for two years I was not able to find a single sponsoring agency who had a sufficiently large slot allocation to assist. Finally, after over a year, with five generous individuals who agreed to act as guarantors, Jewish Immigrant Aid Services in Toronto indicated they had the slots and would sponsor a refugee application for the family, provided we raised the necessary funds to guarantee support for family for their first year in Canada—a government requirement. After five months of fundraising, we achieved the goal, and the full application was submitted to the government of Canada. I have always found it poetic that the organization in Canada that has been willing to help save this Muslim family is a Jewish organization. Perhaps, in the midst of all the horrible antisemitism that has blossomed in the world over the past years, this provide a useful example that religious differences need not always be a source of discord and hatred. That was 18 months ago. In spite of having fulfilled at the requirements, the backlog of cases is such that we knew it could take up to two years for the application to be processed. In the interim the family was able to travel to Pakistan. But their visas have expired and Pakistan is now deporting Afghan refugees back to Afghanistan. The family is in hiding in Pakistan, not able to leave their house. The girls are growing and one of them managed to learn enough English to get a prized scholarship to study online at a US university abroad, where she is studying psychology, as the law degree that she really wants is not available. The family agreed to be interviewed for this podcast. Their images have been washed out for their protection, and their names have been changed as well. We are hoping this podcast will help spur some of you to provide support through Claire’s online site to help provide essentials for the family while they are in hiding, and that it might also help motivate some of you who might live in Canada to help us lobby the government to ensure that their case is resolved as quickly as possible. Thanks for watching, or listening, and for any help you can provide. Here is a gofundme link to help support them. https://www.gofundme.com/f/please-help-five-afghan-girls-get-to-safety

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