Podcaster: Host : Fraser Cain ; Guest: Dr. Kevin Croker, Dr. Kimberly Cartier, Dave Dickinson

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Title: Weekly Space Hangout – Dr. Kevin Croker Explains “Cosmological Coupling”

Link: Cosmoquest:


Today’s story:

  •  JWST!
  • Planets gone rogue?
  • What’s coming up in 2022.

[Editor Rich: I’m not sure that there’s anything we can do about the audio dropout problem till Fraser can move into his new house/studio next summer. Please bear with us while we try to be flexible. Thank you!]

Host: Fraser Cain ( @fcain )

Special Guest: This week marks the final episode of 2021, and we are excited to welcome Dr. Kevin Croker from University of Hawai’i at Mānoa! Kevin led a team that compared data from simulated black hole mergers with that from gravitational waves detected by the LIGO–Virgo collaboration. This comparison led to a surprising conclusion: ignoring the expansion of the universe may be limiting the scientific understanding of black-hole physics. The team hypothesizes that that as the universe expands outward following the Big Bang, all objects with mass grow as well – and Black Holes are no exception. This new process has been dubbed “Cosmological Coupling.”

Kevin Croker is a theoretical astrophysicist in the Department of Physics and Astronomy at the University of Hawai`i at Manoa. He received his PhD in Hawai`i under the supervision of Dr. John Learned, with guidance from Dr. Joel Weiner in the Department of Mathematics and members of the Institute for Astronomy.

Kevin’s research focuses on formal aspects and observational consequences of Einstein’s theory of gravitation, General Relativity.

Prior to graduate training in physics, Kevin worked as lead engineer for the underground radio station KWUR 90.3FM at Washington University in St. Louis, where he received an undergraduate degree in Computer Science.

He is a Fulbright program alumnus and enjoys living, working, and exploring in any place that will have him.

You can read about Kevin’s research in articles at PhysicsWorld: and LiveScience:

The research is also described in The Astrophysical Journal Letters:

Regular Guests:

Today’s sponsor:  Big thanks to our Patreon supporters this month: Rob Leeson, David Bowes, Ron Diehl, Brett Duane, Benett Bolek, Mary Ann, Frank Frankovic, Michael Freedman, Kim Hay, Steven Emert, Frank Tippin, Rani Bush, Jako Danar, Joseph J. Biernat, Nik Whitehead, Semyon Torfason, Michael W, Cherry Wood, Steve Nerlich, Steven Kluth, James K Wood, Katrina Ince, Phyllis Foster, Don Swartwout, Barbara Geier, Steven Jansen

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End of podcast:

365 Days of Astronomy

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After 10 years, the 365 Days of Astronomy podcast is poised to enter its second decade of sharing important milestone in space exploration and astronomy discoveries. Join us and share your story. Until tomorrow! Goodbye!