Podcast Summary: New Books Network
Episode: Jonas Enander, "Facing Infinity: Black Holes and Our Place on Earth" (The Experiment Press, 2025)
Host: Gregory McNiff
Guest: Jonas Enander
Date: September 23, 2025
Overview
This episode features a detailed interview with science writer and cosmologist Jonas Enander about his book Facing Infinity: Black Holes and Our Place on Earth. The book explores the science, history, philosophy, and cultural implications of black holes, blending rigorous astrophysical research with accessible explanations and broader reflection on humanity’s quest to understand the cosmos.
The conversation covers the history of black hole theory, recent breakthroughs in observation, the role of mathematics, cultural intersections in astronomical research, and how black holes influence not only our understanding of the universe but also technologies and knowledge here on Earth.
Episode Breakdown & Key Discussion Points
1. Why Write About Black Holes? (04:00–05:10)
- Jonas Enander was inspired by the first published image of a black hole in 2019 and the wonder it evoked.
- Intended the book for a general audience interested in space, including philosophical, cultural, and political aspects.
"The starting point for this book was the image, the first ever published image of a Black Hole in 2019... I was really awestruck."
— Jonas Enander [04:05]
2. What Is a Black Hole? (05:40–06:27)
- Defined as a region in the universe where gravity is so strong that not even light can escape.
- For a long time, their existence was purely theoretical.
3. Historical Context: The Early Thinkers (06:27–09:15)
- Early ideas date back to John Michell (an English clergyman) in 1783, who speculated about celestial bodies with gravity strong enough to trap light.
- The concept resurfaced with Einstein’s general relativity and was formally described by Karl Schwarzschild in 1915.
"It was, rather surprisingly, a clergyman... named John Michell."
— Jonas Enander [06:49]
4. Theory Before Discovery (09:15–10:50)
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Black holes were a mathematical prediction for decades before direct evidence appeared.
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Einstein himself doubted their physical existence for years.
"...for black holes, it was pure mathematics. That was the way they appeared first."
— Jonas Enander [09:54]
5. The Mathematics of Curved Space (15:13–18:59)
- Non-Euclidean geometry (Bolyai, Gauss, Lobachevsky) was crucial for Einstein’s work and black hole theory.
- Collaboration was key: "Einstein was a very collaborative person who sought help from other people to solve the problems he wanted to solve."
— Jonas Enander [17:55]
6. The Modern Black Hole: Event Horizon & Singularity (19:35–21:58)
- Modern view focuses on the event horizon (the point of no return) and the singularity (where space-time curvature becomes infinite).
"The surface of a black hole is not made out of anything. It's pure space and time that kind of has curved so much that it closes in on itself." — Jonas Enander [19:35]
7. Black Holes in Our Galaxy — Sagittarius A* (23:55–28:14)
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The Milky Way’s center holds a supermassive black hole, Sagittarius A*, with a mass of 4 million Suns.
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Observations by Andrea Ghez and Reinhard Genzel established its presence (Nobel Prize, 2020).
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Other matter—including stars and gas—also influences the galaxy’s dynamics.
"Sagittarius A has a mass of about 4 million suns compressed into a volume that's a bit smaller than the orbit of Mercury..."
— Jonas Enander [24:33]
8. The Critical Role of Mathematics (29:03–29:37)
- Mathematical analysis remains the only way to understand the interior of black holes:
"...if you want to know what happens inside a black hole, the only thing we can send there is our mathematics, is our equations..."
— Jonas Enander [29:03]
9. Chandrasekhar and Stellar Collapse (29:56–33:46)
- S. Chandrasekhar discovered the mass limit (about 1.4 solar masses) beyond which a white dwarf collapses, leading eventually to black holes; this was foundational to understanding dying stars.
- He was initially ridiculed but ultimately awarded the Nobel Prize.
10. How Many Black Holes? (34:09–34:49)
- The Milky Way could contain over 100 million stellar-mass black holes, but only one supermassive black hole (Sagittarius A*).
11. Formation and Evolution of Black Holes (35:08–41:11)
- Stellar-mass black holes form from collapsed massive stars. If the mass is sufficient, the collapse proceeds past the neutron star stage to a black hole.
- Supermassive black holes present a mystery: they formed very early and grew rapidly, possibly through merging or collapsing large gas clouds.
"It's like looking at photos from kindergarten, and you see that everyone looks like an adult..."
— Jonas Enander [37:39]
12. Roy Kerr and Rotating Black Holes (41:42–45:04)
- Roy Kerr discovered the solution for rotating (Kerr) black holes, introducing the concept of the ergosphere, where space-time itself rotates.
- Black holes can produce powerful jets of energy and matter outside the event horizon, larger than their parent galaxies.
"When they eat, they kind of eat like babies. Like, things just end up all over the place."
— Jonas Enander [46:21]
13. Gravitational Waves: LIGO and Beyond (47:17–52:13)
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LIGO detected gravitational waves from black hole collisions, validating Einstein’s prediction and providing new tools for studying extreme cosmic events.
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The LISA mission will target gravitational waves from supermassive black hole mergers from space.
"The precision required is insane. They need to monitor displacements of the mirrors... less than 1 10,000 of the size of a proton."
— Jonas Enander [49:18]
14. Black Holes, Society, and Culture (53:08–55:42)
- The construction of telescopes, like Hawaii’s Thirty Meter Telescope, raises questions about indigenous rights and the cultural significance of observation sites.
- These debates reflect broader societal issues inherent in astronomical research.
"It became quite a crisis for astronomy... the question of where the telescopes stand and how they're built and who has access to them and what happens to the local communities..."
— Jonas Enander [54:14]
15. Black Holes and Earth Science (55:42–59:14)
- Black holes and their bright environments (quasars) serve as cosmic beacons, helping scientists precisely measure continental drift and the Earth’s rotation via the International Celestial Reference Frame.
"We actually use black holes to learn more about how the Earth rotates and how the continents move. And how's that even possible?"
— Jonas Enander [56:16]
16. Black Holes and the Origins of Life (59:29–61:07)
- Speculation exists that black holes and their jets may help distribute essential elements, possibly fostering life elsewhere in the universe.
17. Stephen Hawking, Hawking Radiation, and the Information Paradox (61:07–63:24)
- Stephen Hawking theorized that black holes emit Hawking radiation, making them not entirely black.
- This process raises profound questions about the fate of information falling into black holes.
18. Duality: The Essence of Black Holes (63:13–64:47)
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Enander concludes that the best word for black holes is duality—they are both simple and complex, destructive and creative, cosmic and intimately connected to Earth.
"Black holes are a kind of unity of opposites, in a sense. So they are black, but they create some of the brightest phenomena in the universe..."
— Jonas Enander [63:24]
19. The Future of Black Hole Research (64:47–66:23)
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Advances in imaging (movies from the Event Horizon Telescope), further gravitational wave observations, and resolving the information paradox represent the next frontiers.
"We live in the age of black hole astronomy, and I think that's really true."
— Jonas Enander [66:20]
Notable Quotes & Memorable Moments
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On the first black hole image:
"I was really awestruck... I decided that I wanted to kind of learn more about our current state of knowledge about black holes."
— Jonas Enander [04:05] -
On Einstein's skepticism:
"Einstein himself doubted one of the most profound predictions from his own equations. And that kind of shows you how weird and complicated the mathematics was..."
— Jonas Enander [13:40] -
On technological marvels:
"The precision required is insane. They need to monitor displacements... less than 1 10,000 of the size of a proton..."
— Jonas Enander [49:18] -
On the social dimension of science:
"It turned out that... the question of where the telescopes stand and how they're built and who has access to them... that's a huge question and has a huge societal impact."
— Jonas Enander [54:14] -
On the paradoxical nature of black holes:
"They are black, but they create some of the brightest phenomena in the universe... there's a lot of this interplay between opposites all the time."
— Jonas Enander [63:24]
Timestamps for Key Segments
- 04:00 — Inspiration for the book & intended audience
- 05:40 — Defining black holes
- 06:49 — John Michell and the 18th-century idea of "dark stars"
- 13:40 — Einstein's skepticism, the role of mathematics
- 15:13 — Non-Euclidean geometry's role in understanding space-time
- 19:35 — Modern concept: event horizon, singularity
- 23:55 — Sagittarius A*: The Milky Way’s black hole
- 29:56 — Chandrasekhar’s limit and stellar collapse
- 34:09 — Number and types of black holes in the Milky Way
- 35:08 — How black holes form from dying stars
- 37:39 — The mystery of early supermassive black holes
- 41:42 — Roy Kerr, the spinning black hole, and jets
- 47:40 — Gravitational waves: LIGO and LISA
- 53:08 — Astronomy, indigenous rights, and cultural context
- 55:42 — Navigational uses of quasars and black holes
- 59:29 — Black holes' possible role in origin of life
- 61:07 — Hawking radiation and information paradox
- 63:24 — The "duality" of black holes
- 64:47 — The future: imaging, gravitational waves, paradoxes
Tone & Language
The conversation is enthusiastic, accessible, and thoughtful, blending deep scientific explanation with anecdotes, biography, and philosophical reflection. Enander and McNiff maintain an inviting tone, keen to make complex ideas digestible and to draw connections between cosmic phenomena and earthly, even personal, experience.
Conclusion
The episode offers not just a primer on black holes but a sweeping narrative of how science, culture, and the human search for knowledge are intertwined. Facing Infinity—both the book and the discussion—invites awe at the cosmos and curiosity about our own place within it, highlighting how black holes, the darkest objects in space, illuminate new paths in human understanding.