# What's Eating the Universe? *By Paul Davies. Subtitle: And Other Cosmic Questions. London: Allen Lane, 2 September 2021; Chicago: University of Chicago Press, 2021. UK hardcover ISBN 978-0-241-45985-0; US hardcover ISBN 978-0-226-81629-6. A theoretical physicist, cosmologist and astrobiologist at Arizona State University gives a short tour of cosmology in thirty mini-chapters, most of them titled as questions. The tour runs from the COBE map of the Big Bang afterglow and Newton's infinite universe, through the Big Bang, dark matter, dark energy, black holes and time travel, to the multiverse, fine-tuning, alien life and the fate of the universe. It ends with the question Davies cares most about: why the universe is comprehensible at all.* > **What I actually read.** The book is in copyright (© Paul Davies 2021). There is no legal free copy and no Internet Archive scan. I read the **publisher's own sample** (19 pages: title and copyright pages, the **full contents list with chapter start pages**, the **whole Preface**, **chapter 1** and **chapter 2 to p. 8**), which Penguin supplies to retailers and the Portuguese bookseller Fnac hosts. I also read the **University of Chicago Press excerpt**, which runs on to the end of chapter 2. For chapters 3–30 I did **not** read the text. Those descriptions are built from (a) reviews that describe or quote particular chapters (*Times Higher Education*, *Physics World*, *Publishers Weekly*, *Foreword Reviews*, *Forbes*, *The Wall Street Journal* and Brian Clegg's Popular Science review), (b) Davies's own interview about the book for the John Templeton Foundation, and (c) his Royal Institution lecture on the book (filmed 21 September 2021), whose YouTube transcript I read. Where the only basis for a chapter description is its title, or a talk that may not follow the chapter, I say so. Quotations are from the sample, or as the named source quotes them. Page numbers are chapter start pages from the Allen Lane contents page; I give no others. Related in this vault: the source video note [[Video Summaries/Big Think/The laws of the universe are unable to explain these origin mysteries Paul Davies Full Interview]]. The same interview put Schrödinger's [[Book Summaries/Schrödinger, Erwin/What Is Life - Erwin Schrödinger|What Is Life?]] in the queue, and Davies's *The Demon in the Machine* and *The Goldilocks Enigma* are queued next. ## 1. Book facts | | | |---|---| | Title | *What's Eating the Universe? And Other Cosmic Questions* (title page: "What's Eating the Universe? and Other Cosmic Questions") | | Author | Paul Davies (P. C. W. Davies; full name Paul Charles William Davies), Regents' Professor of Physics and director of the Beyond Center for Fundamental Concepts in Science, Arizona State University | | First edition (UK) | London: Allen Lane, an imprint of Penguin Random House UK, 2021 ("First published 2021"). Published 2 September 2021 (*Times Higher Education*; Audible). £16.99 hardcover, 192 pp. per the publisher (*Physics World*). Set in Garamond by Jouve (UK); 13 figures, with photographs courtesy of NASA, a Cardozo Kindersley inscription (fig. 9) and a Westminster Abbey image (fig. 13) ([publisher's sample](https://static.fnac-static.com/multimedia/PT/pdf/9780241459850.pdf)) | | US edition | Chicago: University of Chicago Press, 2021. Cloth ISBN 978-0-226-81629-6; paper 978-0-226-82387-4 (2022); ebook 978-0-226-81632-6; DOI 10.7208/chicago/9780226816326.001.0001. LCC QB982 .D383 2021; DDC 523.1; LCCN 2021004010 ([BiblioVault](https://www.bibliovault.org/BV.book.epl?ISBN=9780226816296); [UChicago Press](https://press.uchicago.edu/ucp/books/book/chicago/W/bo126163512.html)). Sources differ on the US date: *Foreword Reviews* gives 24 August 2021, Open Library 7 September 2021, and the US Kindle edition 22 September 2021. A catalog record gives "viii, 172 pages: illustrations; 23 cm" ([ECU Libraries](https://librarycatalog.ecu.edu/catalog/6792841)); the press lists 208 pages, 17 halftones and 1 table | | Other ISBNs | Penguin paperback 978-0-14-199372-0 (2022, 192 pp. per *Publishers Weekly*); Penguin ebook 978-0-14-199373-7; audiobook 978-0-241-52927-0 ([Open Library work](https://openlibrary.org/works/OL24490629W); [OL 2022 work](https://openlibrary.org/works/OL26772986W); [OL ebook](https://openlibrary.org/works/OL28356291W)) | | Structure | Preface (dated "Phoenix, March 2021"); 30 short chapters (about 2–11 pages each); index. The contents list shows **no notes or bibliography** | | Audiobook | Unabridged, read by Marston York, 4 h 30 min, Allen Lane, 2 September 2021 ([Audible](https://www.audible.com/pd/Whats-Eating-the-Universe-Audiobook/0241529271)) | | Translations | A Greek edition, *Τι τρώει το σύμπαν;*, was out by March 2022 ([Greek blog post](https://kostasvakouftsis.blogspot.com/2022/03/whats-eating-universe.html)); I did not identify its publisher | | Cover | [Open Library cover](https://covers.openlibrary.org/b/id/11107379-L.jpg). The US cover image is the Planck map of the cosmic microwave background | **Where it came up.** - Video: [The laws of the universe are unable to explain these origin mysteries | Paul Davies: Full Interview](https://www.youtube.com/watch?v=e41IyOlfj7I), Big Think, published 2026-11-06, at [0:15](https://www.youtube.com/watch?v=e41IyOlfj7I&t=15s). In his introduction Davies names it as the most recent of his 30-plus books, before *The Demon in the Machine*. The interview itself is about the origin of life, information and fine-tuning, not about this book. - Requested by Video Summaries on 2026-11-06. - Vault note: [[Video Summaries/Big Think/The laws of the universe are unable to explain these origin mysteries Paul Davies Full Interview]]. ## 2. Book resources **Reference and catalog pages.** Publishers: [University of Chicago Press](https://press.uchicago.edu/ucp/books/book/chicago/W/bo126163512.html) (blurb, full contents, review quotes and a long excerpt from chapters 1–2); [Penguin UK paperback](https://www.penguin.co.uk/books/319131/whats-eating-the-universe-by-davies-paul/9780141993720); [BiblioVault](https://www.bibliovault.org/BV.book.epl?ISBN=9780226816296); [ASU Beyond Center book page](https://cosmos.asu.edu/publication/whats-eating-universe). Open Library: [OL24490629W](https://openlibrary.org/works/OL24490629W) (2021 Allen Lane and Chicago hardcovers), [OL26772986W](https://openlibrary.org/works/OL26772986W) (2022 paperbacks). Google Books: [search by ISBN](https://books.google.com/books?vid=ISBN9780226816296). The Google Books API was over its daily quota during this run, so I could not check whether a preview exists. WorldCat: [search by ISBN 9780226816296](https://search.worldcat.org/search?q=bn%3A9780226816296); I did not find an OCLC number. De Gruyter hosts the Chicago ebook chapter by chapter under DOI prefix [10.7208/chicago/9780226816326](https://doi.org/10.7208/chicago/9780226816326.001.0001) (institutional access). **Free (legal).** - **No legal free full text.** The book is in copyright (2021). Project Gutenberg: not applicable. - **Free samples:** the publisher's 19-page sample PDF (contents, Preface, ch. 1, start of ch. 2), [hosted by Fnac](https://static.fnac-static.com/multimedia/PT/pdf/9780241459850.pdf), and the [UChicago Press excerpt](https://press.uchicago.edu/ucp/books/book/chicago/W/bo126163512.html) (chs. 1–2). - **Internet Archive lending / Open Library borrow: no.** An Internet Archive search (title "eating universe", creator "davies") returns nothing, and Open Library lists no borrowable edition (every record shows "no_ebook"). - **Libby/OverDrive: yes, all three formats.** OverDrive carries the Penguin ebook ([6089420](https://www.overdrive.com/media/6089420/whats-eating-the-universe)), the Chicago ebook ([6430189](https://www.overdrive.com/media/6430189/whats-eating-the-universe)) and the Marston York audiobook ([6187518](https://www.overdrive.com/media/6187518/whats-eating-the-universe)). Whether your library has them varies; check in Libby. UK libraries also lend it through BorrowBox. - **Hoopla: not found.** A web search turned up no Hoopla listing. - **Print at your library:** widely held, for example [East Carolina University](https://librarycatalog.ecu.edu/catalog/6792841) (as an EBSCO ebook). - **Unauthorized copies:** several "read online free" and ebook-download sites carry the full text. They are pirated, and I neither used nor link them. **Paid.** - **Amazon print.** Chicago hardcover [022681629X](https://www.amazon.com/dp/022681629X); Chicago paperback [0226823873](https://www.amazon.com/dp/0226823873); Allen Lane hardcover [0241459850](https://www.amazon.com/dp/0241459850). - **Kindle.** Yes. Amazon shows two Kindle editions: [B08PP73V5K](https://www.amazon.com/dp/B08PP73V5K) and [B096L2WP51](https://www.amazon.com/dp/B096L2WP51) (the latter is the Amazon UK Kindle edition). I could not confirm which publisher's edition each one is. - **Audible.** Yes: [0241529271](https://www.audible.com/pd/Whats-Eating-the-Universe-Audiobook/0241529271), read by Marston York, 4 h 30 min. - **Other:** [Bookshop.org](https://bookshop.org/p/books/what-s-eating-the-universe-and-other-cosmic-questions-paul-davies/35431a2ff169f087?ean=9780226816296); [Penguin UK](https://www.penguin.co.uk/books/319131/whats-eating-the-universe-by-davies-paul/9780141993720). ## 3. Author biography **Paul Charles William Davies** was born in London on 22 April 1946 and grew up in Finchley. He took a first-class BSc in physics at University College London in 1967 and a PhD there in 1970, under Michael Seaton and Sigurd Zienau. His thesis was on radiation damping and a quantum theory of Wheeler–Feynman electrodynamics. He then did postdoctoral work under Fred Hoyle at Cambridge ([Wikipedia](https://en.wikipedia.org/wiki/Paul_Davies)). In his Royal Institution lecture on this book he says Hoyle "gave me my first job", and that his PhD topic had been the arrow of time ([Ri lecture](https://www.youtube.com/watch?v=08aLgCb56_w)). He held posts at Cambridge, King's College London and Newcastle from 1970 to 1990, then at Adelaide and Macquarie universities in Australia from 1990 to 2006, where he helped found the Australian Centre for Astrobiology. He then moved to Arizona State University, where he directs the Beyond Center and is Regents' Professor ([*Times Higher Education*](https://www.timeshighereducation.com/books/whats-eating-universe-paul-davies); [Wikipedia](https://en.wikipedia.org/wiki/Paul_Davies)). His research is mainly in quantum field theory in curved spacetime. Two results carry his name: the **Fulling–Davies–Unruh effect**, under which an accelerating observer sees a thermal bath, and the **Bunch–Davies vacuum**, which is used in explaining the CMB fluctuations left by inflation. He also works on black holes, the arrow of time and astrobiology. He was an early advocate of the idea that life on Earth could have come from Mars, and he has proposed searching for a "shadow biosphere". He chairs the SETI Post-Detection Science and Technology Taskgroup of the International Academy of Astronautics, and he has led an NCI-funded physics-of-cancer program at ASU ([Wikipedia](https://en.wikipedia.org/wiki/Paul_Davies); [Royal Institution](https://www.rigb.org/explore-science/explore/video/whats-eating-universe-paul-davies)). He co-authored the 2011 *Science* "arsenic life" paper (Wolfe-Simon et al.). The paper was refuted in 2012 and retracted in 2025 ([Retraction Watch](https://retractionwatch.com/2025/07/24/science-retraction-arsenic-life-nasa-astrobiology/)). He has written about 30 popular books, among them *The Mind of God* (1992), *About Time* (1995), *How to Build a Time Machine* (2001), *The Goldilocks Enigma* (2006), *The Eerie Silence* (2010) and *The Demon in the Machine* (2019). His honours include the **Templeton Prize (1995)**, the Institute of Physics Kelvin Medal (2001), the Royal Society's Faraday Prize (2002), membership of the Order of Australia (2007) and the asteroid 6870 Pauldavies ([Wikipedia](https://en.wikipedia.org/wiki/Paul_Davies); [Templeton Foundation](https://www.templeton.org/news/paul-davies-on-whats-eating-the-universe)). His public writing on science and religion has drawn criticism from atheist scientists, for example the Edge.org responses to his 2007 *New York Times* op-ed "Taking Science on Faith" ([NYT](https://www.nytimes.com/2007/11/24/opinion/24davies.html)). ## 4. Author interviews and talks - **Royal Institution lecture, "What's eating the universe?" (filmed 21 September 2021, released 19 May 2022)**: [Ri page](https://www.rigb.org/explore-science/explore/video/whats-eating-universe-paul-davies); [YouTube](https://www.youtube.com/watch?v=08aLgCb56_w); [Q&A](https://youtu.be/IRHIGzWfG0Y). A one-hour tour of the book's arc: Slipher and Hubble, Hoyle, the CMB, the no-boundary proposal, Bunch–Davies fluctuations, the "botched job" anomalies, the Eridanus cold spot, dark energy, the big rip, "death by devourment", and SETI. I read the transcript; I did not watch the Q&A. - **John Templeton Foundation Q&A with Nate Barksdale (23 September 2021)**: [templeton.org](https://www.templeton.org/news/paul-davies-on-whats-eating-the-universe). Why he chose these questions, COBE and cosmology's "golden age", the absence of equations, and comprehensibility. - **ABC Radio National, *Conversations* with Richard Fidler, "The mystery of the hole in the universe" (16 September 2021)**: [ABC listen](https://www.abc.net.au/listen/programs/conversations/paul-davies-the-universe-mysteries-of-the-cosmos/13535374). What came before the Big Bang, colliding universes, and why we can understand the cosmos. Not listened to. - **Physics World Weekly podcast with Hamish Johnston (9 September 2021)**: [Physics World](https://physicsworld.com/a/pondering-cosmic-mysteries-with-paul-davies-tandem-solar-cells-could-soon-be-on-your-roof/). The book, plus tips for science writers. Not listened to. - ***The Cosmic Controversy* podcast, episode 66, with Bruce Dorminey (3 September 2021)**: [Podbean](https://brucedorminey.podbean.com/e/episode-66-the-big-questions-about-the-cosmos-and-our-existence/). Why there is something rather than nothing, and the book. Not listened to. - ***Finding Genius* podcast, "Cosmic Mysteries: From Aliens to Cancer Treatments" (2021, before publication)**: [findinggeniuspodcast.com](https://www.findinggeniuspodcast.com/podcasts/cosmic-mysteries-from-aliens-to-cancer-treatments-the-timeless-importance-of-the-study-of-physics/). Mars, life beyond Earth, and physics in cancer research. Not listened to. - **IAI TV, "What's eating the universe?"**: [iai.tv](https://iai.tv/video/whats-eating-the-universe-paul-davies) (paywalled; not watched). *Physics World* notes he debated "the fluid nature of physical laws" at HowTheLightGetsIn, London, in September 2021. - **Big Think, "The laws of the universe are unable to explain these origin mysteries" (6 November 2026)**: [YouTube](https://www.youtube.com/watch?v=e41IyOlfj7I). The source of this queue entry. He names the book at the start; the interview is about life as chemistry plus information, missing laws, a second genesis and the Goldilocks enigma. ## 5. Summary **Thesis.** Davies calls the book "a scientific detective story". In the Preface he says it "explains how age-old cosmic puzzles have recently been solved, while startling new discoveries are upending our understanding of physical reality", and that he "conceived of this book as a concise summary of our current state of understanding" (publisher's sample). He makes three connected claims. **First,** since COBE, cosmology has gone "from a speculative backwater to a precision science", and "Paradoxically, we now understand the history of the universe in its overall outline better than we understand the history of our own planet" (ch. 1). **Second,** every answer has opened new riddles: dark matter, dark energy, CMB anomalies and the Eridanus cold spot, the multiverse, and the fine-tuning of the laws for life. **Third,** the deepest mystery is that "on an unexceptional planet orbiting a run-of-the-mill star, a species of organism evolved that managed to work out how the world is put together", which "surely tells us something deeply significant about our place in the natural order. But what?" (ch. 1). He returns to this in ch. 29. In the Templeton interview he explains the design: perennial "big questions" alternate with "curious and quirky" questions, such as why it is dark at night or the speed of space, that teach the background science ([Templeton](https://www.templeton.org/news/paul-davies-on-whats-eating-the-universe)). *Nature Astronomy*'s reviewer notes that the chapters run "roughly in chronological order of the observations and theoretical advances to which they relate" (quoted by the [press](https://press.uchicago.edu/ucp/books/book/chicago/W/bo126163512.html)). **Outline (Allen Lane 2021; chapter titles and start pages from the contents page).** The book is not divided into parts. I group the chapters below by theme for readability; the grouping is mine. The source of each chapter description is noted. *Preface* (p. vii; **read**). Cosmology "weaves together the large and the small". Against the view that science strips away romance, he writes that "the deeper we probe, the more beautiful and awe-inspiring the physical world appears… It is good that we should know." He promises to examine "why the universe exists at all, why it has the form it does, why the laws of nature are as they are, and how a system of mindless, purposeless particles brought forth conscious, thinking beings". He acknowledges colleagues, including Glenn Starkman "for his inspirational lecture about the oddities in the cosmic microwave background radiation", his wife Pauline, and his Penguin editor Chloe Currens. **Setting the scene (chs. 1–3)** 1. **Journey from the Edge of Time** (p. 1; **read**). Opens on the COBE all-sky map, the "mottled red-and-blue image" that Smoot said "was like looking at the face of God" and Hawking called "one of the greatest scientific discoveries of the century, if not all time" (dated in the text to 14 January 1990; see fact-check). COBE "ushered in a golden age of cosmology". He borrows Churchill: "this is not the end of cosmology. It is not even the beginning of the end. But it is, perhaps, the end of the beginning." Cosmology answers the need once met by creation myths. The Greek word *kosmos* shares a root with "cosmetic" (beautiful, whole, ordered), in contrast to chaos. Copernicus (1543) shattered the anthropocentric model, and "Today we are poised to undergo a shift in perspective even more disruptive than that initiated by Copernicus." Brian Clegg calls this last line "frankly, hype". 2. **The Search for the Key to the Universe** (p. 4; **read**, via the sample plus the UChicago excerpt). Ancient sky-watching had practical uses (navigation, crops, calendars), and megaliths were aligned to the sky. Then the sky came to be seen as a mechanism, culminating in Ptolemy's nested spheres (fig. 2). The "stunning conceptual pivot" of the 17th century put the key in "laws of nature that transcend the physical world", in "a kind of cosmic code". He quotes Galileo ("The great book of nature is written in the language of mathematics", dated in the text to 1632) and Jeans ("The universe appears to have been designed by a pure mathematician!"). The founders of science were "more like members of an exclusive cult". Newton invented fluxions, helped by "the need to self-isolate at home in Lincolnshire during the great plague of 1665–6", and found the inverse-square law. Davies recalls the student thrill of seeing "out popped the formula for an ellipse!" Newton then asked why an infinite cosmos does not collapse. His answer, an infinite universe in balance, was "something of an intellectual sleight of hand", and Newton conceded it was unstable ("as hard as to make not one needle only but an infinite number of them… stand accurately poised upon their points"). The chapter closes: "the answer was hiding in plain sight—right above our heads." 3. **Why is It Dark at Night?** (p. 10; not read). The chapter title and the cliff-hanger ending of ch. 2 point to **Olbers' paradox**: in an infinite, eternal, static universe of stars, the night sky should blaze. *Publishers Weekly* says the chapter "covers the brightness of stars". *Foreword Reviews* cites the "nugget" that "the combined light of the stars equates to less than a ten-billionth of the brightness of the sun", probably from this chapter (placement unverified). **The expanding universe (chs. 4–9)** 4. **The Big Bang** (p. 15; not read). At nine pages it is one of the longest chapters. To judge from the Ri lecture, the story covers Slipher's redshifts at Lowell Observatory, Hubble, Lemaître's "cosmic egg", Hoyle's steady state and his coining of "big bang", and the discovery of the CMB with its blackbody spectrum. Brian Clegg complains that the chapter does not even name Penzias and Wilson, and that "the infamous pigeon droppings get such a passing mention" ([Popular Science](https://popsciencebooks.blogspot.com/2021/09/whats-eating-universe-paul-davis.html)). 5. **Where is the Centre of the Universe?** (p. 24; not read). The answer, as the Ri lecture gives it, is that the expansion is of space itself, with "no center and no edge". *Foreword Reviews* describes a classroom analogy for the expansion, probably from this chapter (placement unverified): students holding hands in a circle around their teacher all take five steps back. 6. **Why the Cosmos is Actually Fairly Simple** (p. 28; not read). *Foreword Reviews*: "Paul Davies argues that the universe is simple, operating in accordance with the universal laws of physics." The Ri lecture stresses the near-perfect smoothness of the CMB once the Earth's motion is removed. 7. **What is the Speed of Space?** (p. 31; not read). In the Templeton interview Davies names this as one of the background questions that "set out the conceptual framework". In the Ri lecture he says that "somewhere in the book" he works out how many litres of new space appear in the universe every day. This chapter is the likely place, but that is unverified. 8. **What is the Shape of Space?** (p. 37; not read). Title only: at nine pages, presumably about the geometry and curvature of the universe. Unverified. 9. **Explaining the Cosmic Big Fix** (p. 46; not read). Probably the "fine-tuned" expansion rate and its explanation by inflation. The Ri lecture: "the rate of expansion matches the gravitating power of the universe almost precisely. And that mystery is explained by the inflation theory." Mapping this to ch. 9 is unverified. **The dark side and matter (chs. 10–12)** 10. **Most of Our Universe is Missing** (p. 49; not read). Dark matter. Cait MacPhee notes that Davies introduces it by analogy with Neptune, "one of a long list of unseen, unseeable or just plain dim entities that were discovered by the way they tug on their more visible neighbours". She warns that this may mislead readers into thinking dark matter is just an unseen object ([*THE*](https://www.timeshighereducation.com/books/whats-eating-universe-paul-davies)). Clegg objects that "dark matter is stated as if its existence were a known fact… nor a single mention of modified gravity theories." 11. **What is Dark Energy?** (p. 53; not read). The accelerating expansion found in the late 1990s, and Einstein's 1917 cosmological term, recast as "the weight of empty space" (Ri lecture). Why the vacuum energy is so small remains, in the Ri lecture, "one of the great unsolved problems of cosmology". 12. **Where Does Matter Come From?** (p. 59; not read). Title only, at nine pages. *Physics Today* says the book covers antimatter, and in the Templeton interview Davies cites antimatter as something found only through theory. A photo of Dirac's Westminster Abbey memorial (with his equation) appears in the book, per Templeton. Placing these in this chapter is unverified. **Gravity, time and black holes (chs. 13–17)** 13. **Gravity Conquers All** (p. 68; not read). Title only: presumably gravitational collapse, from stars to black holes. Unverified. 14. **Warped Time and Black Holes** (p. 72; not read). *Publishers Weekly*: Davies "describes antimatter, warped time, and black holes in a conversational tone". 15. **Is Time Travel Possible?** (p. 78; not read). *Publishers Weekly*: it "explains relativity (and offers 'maybe' as an answer)". *Foreword Reviews*: "time travel is possible in principle, according to the theory of relativity." 16. **What is the Source of Time's Puzzling Arrow?** (p. 83; not read). This was the subject of Davies's PhD. In the Ri lecture he says "the source of time's arrow can be traced back to the origin of the universe." 17. **The Black Hole Paradox** (p. 88; not read). Title only: presumably Hawking radiation and the information paradox. Templeton notes a photo of Hawking's Westminster Abbey memorial stone, which carries his black-hole temperature formula. Unverified as to chapter. **Unification and origins (chs. 18–22)** 18. **A Theory of Everything?** (p. 93; not read). At eleven pages, the longest chapter. Title and reviews suggest unification of the forces and the Standard Model. Clegg's complaint that "quantum spin is described as if it were literally a matter of particles spinning around" may refer to this chapter (unverified). 19. **Fossils from the Cosmic Dawn** (p. 104; not read). The Ri lecture fits the title: inflation stretched quantum vacuum fluctuations into the CMB hot and cold spots ("the fossils of quantum fluctuations"), which grew into galaxies. Davies describes his own part with Tim Bunch, who worked out the relevant vacuum state at King's College in the 1970s. Mapping to ch. 19 is unverified. 20. **Can the Universe Come from Nothing?** (p. 111; not read). Bruce Dorminey (*Forbes*) reports that Davies divides the answers into two: that 13.8 billion years ago "the cosmos really popped into existence from nothing at all", or that "'something' has always existed". In the Ri lecture the same material covers Augustine's world made "with time and not in time", Hawking's "north of the North Pole" analogy, and the Hartle–Hawking no-boundary proposal. 21. **How Many Universes Are There?** (p. 117; not read). The multiverse of bubble universes. In the Ri lecture, "the picture that is favored among the type of people I have coffee with is that our universe is just one bubble among many", with laws that may differ from bubble to bubble. An Amazon reader review says Davies does not mention Penrose's conformal cyclic cosmology (unverified). 22. **The Goldilocks Enigma** (p. 123; not read). Fine-tuning for life, the subject of his 2006 book. In the Ri lecture's version you have a "designer machine with 30-something knobs", and tiny twiddles "would be lethal". The multiverse offers a "cosmic lottery" explanation. **Threats to the universe (chs. 23–24)** 23. **What's Eating the Universe?** (p. 127; not read; the best-documented chapter). It is four pages long (MacPhee: "all discussed within four pages"). It starts with the CMB **Cold Spot** in Eridanus, "as if something has taken a huge bite out of the universe" (blurb). The suspects are a supermassive black hole, a collision with another bubble universe (Dorminey: Davies credits Laura Mersini-Houghton with popularizing colliding bubbles; such a collision should leave gravitational waves and a distinctive CMB polarization pattern, and searches have so far come up empty), and **vacuum decay**. In vacuum decay, our not-quite-lowest quantum vacuum tunnels to a lower state, and a bubble wall expands at nearly light speed and destroys everything; the idea has "been around since the 1970s". A stranger variant is Witten's 1982 **bubble of nothing**: "It would be a hole in space, not a black hole, but a bubble of no-space, expanding uncontrollably, sweeping all before it and eventually gobbling up the entire universe, leaving only nothing: space totally engulfed by spacelessness" (quoted by [*Forbes*](https://www.forbes.com/sites/brucedorminey/2021/08/30/5-takeaways-when-considering-the-cosmos-remaining-mysteries/)). In the Ri lecture he adds that black holes are eating the universe "from the inside out". *Physics World*: "If you can bear to contemplate such scary prospects, this book is a fun way of making sure you're all caught up". 24. **Is the Universe Actually a Botched Job?** (p. 131; not read; two pages). In the Ri lecture the "botched job" is the CMB's large-angle discrepancies: "Blemishes in an otherwise perfect universe", such as a slight hemispheric lopsidedness. MacPhee's remark that the question of whether tweaked laws could give "something 'better'" is "covered in a couple of pages" probably refers here too. Both readings are unverified against the text. **Life and observers (chs. 25–27)** 25. **Are We Alone?** (p. 133; not read). Astrobiology and the Drake equation. The Ri lecture version: the astronomical terms are now well known, but f_l, the fraction of Earth-like planets on which life emerges, is unknown because nobody knows how life began. He quotes Crick's "almost a miracle" and Darwin's "mere rubbish" line on origins. Davies says he is "personally very skeptical" of intelligent life elsewhere, "out of step with my colleagues". 26. **Is ET in Our Backyard?** (p. 136; not read). *Publishers Weekly*: it "suggests humans are more likely to discover 'robotic surrogates than biological organisms'". MacPhee explains why: alien intelligence may have arisen and died out billions of years ago, leaving only durable machines. Finding them is "the ultimate needle in a fathomless haystack" (MacPhee's words). 27. **Why Am I Living Now?** (p. 141; not read). Title only from sources I could use. The title points to the "why now?" coincidences of cosmic timing, such as observers appearing just when dark energy and matter are comparable, or Dirac's and Dicke's large-number arguments. **Unverified.** **Ends and meaning (chs. 28–30)** 28. **The Fate of Our Universe** (p. 147; not read). *Publishers Weekly* quotes: "Although the idea is currently out of fashion, it remains possible that the universe will eventually collapse to a big crunch." The Ri lecture runs through the older open, closed and critical futures, then acceleration, a cold, dark, empty end, and the **big rip** if dark energy grows. 29. **Is There a Meaning to It All?** (p. 155; not read). The comprehensibility of the universe. *Forbes* quotes: "There is no absolute reason for nature to have a straightforward mathematical subtext in the first place. And even if it does, there is no reason why humans should be capable of comprehending it", and the natural world is linked by "a network of coded mathematical relationships". MacPhee liked best "that the universe has somehow evolved not just awareness but also comprehension of itself." In the Templeton interview, Davies contrasts curve-fitting with understanding (Kepler versus Newton) and says the universe "brings forth comprehension". 30. **What's New on the Cosmic Horizon?** (p. 160; not read). Open problems and prospects. An Amazon reader review lists the Eridanus cold patch, the Hubble-constant discrepancy and physics beyond the Standard Model (unverified). Dorminey reads the ending as a call for "another young Einstein" to unify the theories (Dorminey's words). *Index* (p. 167). **Key ideas.** - **Golden age, new mysteries.** Precision cosmology has explained the universe's history in outline, but it has also exposed riddles: dark matter, dark energy, CMB anomalies. - **Teaching through odd questions.** Short "quirky" chapters (dark night sky, speed of space, centre of the universe) build the concepts that the big questions need. - **The universe may not be safe.** Black holes, bubble collisions, vacuum decay and bubbles of nothing are each, in different ways, "eating" the universe. Davies adds that it has lasted 13.8 billion years without incident. - **Origins without a cause.** Quantum cosmology, as in the no-boundary proposal, lets time "emerge" rather than switch on, which sidesteps "what came before?" - **Multiverse versus fine-tuning.** Many universes with varying laws would explain why ours suits life. Davies presents this as the coffee-room favourite, not as established. - **Comprehensibility is the deepest puzzle.** The universe produced beings who can decode its mathematical laws, and Davies treats this as significant. **Reception.** The reviews broadly agree. The book is accessible, conversational and breathtakingly fast, and it is a good gateway: "a great introduction for readers new to physics" (*Publishers Weekly*), "a good place to start" (*THE*), "a fun way of making sure you're all caught up" (*Physics World*). It is also thin. MacPhee found it "a little unsatisfying" and warned that the "light touch may also give rise to misconceptions". Clegg gave it three stars: it "could have been so much better with just a little work", and some condensation is "so extreme that we lose a considerable amount of accuracy". He also objected to the treatment of dark matter and spin, and to the "hype" about a post-Copernican shift. ## 6. Fact-check Claims are from the sample I read, unless marked as reported by a reviewer or said in the Ri lecture. | Claim | Verdict | Evidence | |---|---|---| | The COBE all-sky map, with Smoot's "face of God" and Hawking's "greatest… discovery" remarks, made the world's press on **14 January 1990** (ch. 1) | **Disputed (date).** COBE's DMR anisotropy map and both remarks date from **23–24 April 1992**. COBE's first headline result, announced at the AAS meeting in January 1990, was the CMB's blackbody **spectrum**, not the anisotropy map. The ch. 1 date appears to conflate the two | [AIP Physics News, 24 Apr 1992 (via Wikipedia COBE)](https://en.wikipedia.org/wiki/Cosmic_Background_Explorer); [NYT, 24 Apr 1992](https://www.nytimes.com/1992/04/24/us/scientists-report-profound-insight-on-how-time-began.html); [Lineweaver, "Inflation and the CMB" (Smoot and Hawking quotes, 1992)](https://ned.ipac.caltech.edu/level5/March03/Lineweaver/Lineweaver7_2.html); [Mather et al. 1990, ApJ 354, L37 (spectrum)](https://ui.adsabs.harvard.edu/abs/1990ApJ...354L..37M) | | Galileo wrote "The great book of nature is written in the language of mathematics" **in 1632** (ch. 2) | **Disputed (date and wording).** The passage is from *Il Saggiatore* (*The Assayer*), **1623**; 1632 is the *Dialogue*. Galileo's wording is "Philosophy is written in this grand book… It is written in the language of mathematics… without these, one is wandering around in a dark labyrinth"; Davies's version is a paraphrase | [Wikipedia: The Assayer](https://en.wikipedia.org/wiki/The_Assayer) | | Jeans: "The universe appears to have been designed by a pure mathematician" (ch. 2) | **Supported in substance; wording paraphrased.** Jeans's words in *The Mysterious Universe* (1930) are "the Great Architect of the Universe now begins to appear as a pure mathematician"; the version Davies gives is a common paraphrase | [Wikiquote: James Jeans](https://en.wikiquote.org/wiki/James_Jeans) | | Copernicus declared in 1543 that the Earth goes around the Sun (ch. 1) | **Supported.** *De revolutionibus*, 1543 | [Wikipedia: De revolutionibus](https://en.wikipedia.org/wiki/De_revolutionibus_orbium_coelestium) | | Newton developed fluxions and the inverse-square law of gravity in his early twenties, partly while at home in Lincolnshire during the plague of 1665–6 (ch. 2) | **Supported.** Newton's *annus mirabilis* at Woolsthorpe, Lincolnshire, while Cambridge was closed by the plague | [Wikipedia: Isaac Newton](https://en.wikipedia.org/wiki/Isaac_Newton) | | Newton conceded an infinite static star system would be unstable: "as hard as to make not one needle only but an infinite number of them… stand accurately poised upon their points" (ch. 2) | **Supported.** Newton's letter to Richard Bentley of 17 January 1692/3 | [Newton Project, THEM00255](https://www.newtonproject.ox.ac.uk/view/texts/normalized/THEM00255) | | The universe is 13.8 billion years old (WSJ review; Ri lecture) | **Supported.** Planck 2018: 13.787 ± 0.020 Gyr | [Planck 2018 results VI](https://arxiv.org/abs/1807.06209) | | There is an anomalously cold, large spot in the CMB toward Eridanus (ch. 23) | **Supported.** Found in WMAP data in 2004 and confirmed by Planck: about 70 μK below average, roughly 5° in radius | [Wikipedia: CMB cold spot](https://en.wikipedia.org/wiki/CMB_cold_spot) | | The Cold Spot's cause is unexplained; a supervoid is one candidate (blurb, ch. 23) | **Supported (open question).** Mackenzie et al. 2017 found no supervoid large enough and suggested a primordial origin. The Dark Energy Survey (Kovács et al., December 2021, after the book) found more support for the Eridanus supervoid link. Still debated | [Mackenzie et al. 2017](https://arxiv.org/abs/1704.03814); [Kovács et al. 2021](https://arxiv.org/abs/2112.07699) | | Laura Mersini-Houghton popularized the idea that the cold spot could come from a collision with another bubble universe (ch. 23 per *Forbes*; Ri lecture) | **Partly disputed (attribution).** Mersini-Houghton's own proposal (with Richard Holman, 2006–08) attributes a giant void to quantum **entanglement** of our universe with others, not to a bubble collision; her 2008 review claims the 2007 void as a confirmed prediction. The bubble-collision interpretation of the Cold Spot is from Chang, Kleban & Levi (2009) and others. She has been the leading public voice for "imprints of other universes", so the shorthand is loose rather than wrong | [Mersini-Houghton 2008, "Birth of the Universe from the Multiverse"](https://arxiv.org/abs/0809.3623); [Chang, Kleban & Levi 2009](https://arxiv.org/abs/0810.5128) | | Searches for bubble-collision imprints in the CMB have come up empty (ch. 23 per *Forbes*) | **Supported.** No statistically compelling detection. Feeney et al. found WMAP features consistent with, but not evidence for, collisions | [Feeney et al. 2011](https://arxiv.org/abs/1012.1995) | | Vacuum decay to a lower-energy state is an idea from the 1970s; a bubble of true vacuum would expand at nearly light speed (ch. 23 per *Forbes*/blog) | **Supported** as theory. Coleman 1977; Coleman & De Luccia 1980. Whether our vacuum is metastable is unknown | [Coleman 1977](https://doi.org/10.1103/PhysRevD.15.2929); [Coleman & De Luccia 1980](https://doi.org/10.1103/PhysRevD.21.3305) | | Edward Witten proposed the "bubble of nothing" in 1982 (ch. 23 per *Forbes*) | **Supported.** Witten, "Instability of the Kaluza-Klein vacuum", *Nucl. Phys. B* 195 (1982) 481. Note that it is a Kaluza–Klein instability, not a feature of ordinary 4-D space | [Witten 1982](https://doi.org/10.1016/0550-3213(82)90007-4); [Wikipedia: Bubble of nothing](https://en.wikipedia.org/wiki/Bubble_of_nothing) | | Neptune was found through its gravitational tug on Uranus (ch. 10 per *THE*) | **Supported.** Predicted by Le Verrier and Adams; found by Galle in 1846 | [Wikipedia: Discovery of Neptune](https://en.wikipedia.org/wiki/Discovery_of_Neptune) | | Dark matter exists and is about five times as abundant as ordinary matter (ch. 10 per reviewers; Ri lecture) | **Supported (mainstream)**, but not settled. ΛCDM fits CMB and structure data (Planck), but the particle is undetected, and modified-gravity alternatives (MOND) have a minority following. Clegg faults the book for not mentioning them | [Planck 2018 results VI](https://arxiv.org/abs/1807.06209); [Wikipedia: Modified Newtonian dynamics](https://en.wikipedia.org/wiki/Modified_Newtonian_dynamics) | | The expansion of the universe has been accelerating, as found in the late 1990s (ch. 11; Ri lecture) | **Supported.** Supernova results of 1998–99; Nobel Prize 2011 | [Nobel Prize in Physics 2011](https://www.nobelprize.org/prizes/physics/2011/summary/) | | Einstein called the cosmological constant his "biggest blunder" (Ri lecture; likely ch. 11, unverified) | **Disputed (attribution).** The remark is known only through George Gamow's later recollection, and historians doubt it | [O'Raifeartaigh & Mitton 2018](https://arxiv.org/abs/1804.06768) | | Time travel is possible in principle according to relativity (ch. 15 per *Foreword*/*PW*) | **Supported with caveats.** Travel to the future through time dilation is established. Some GR solutions allow travel to the past (Gödel 1949; traversable wormholes, Morris–Thorne–Yurtsever 1988), but Hawking's chronology-protection conjecture argues physics forbids it, so "maybe" is fair | [Morris, Thorne & Yurtsever 1988](https://doi.org/10.1103/PhysRevLett.61.1446); [Hawking 1992](https://doi.org/10.1103/PhysRevD.46.603) | | Combined starlight is "less than a ten-billionth of the brightness of the sun" (per *Foreword Reviews*) | **Unverified.** The comparison is ambiguous. Integrated starlight in the night sky is roughly 10⁻⁸ of sunlight at Earth, while the sky's surface brightness relative to the Sun's disc is far smaller still. Without the text I cannot tell which Davies meant | [Foreword Reviews](https://www.forewordreviews.com/reviews/whats-eating-the-universe/) | | We understand the history of the universe in outline better than the history of our own planet (ch. 1) | **Unverified (judgement).** This is a defensible rhetorical claim, not a testable fact | — | | Contact with ET is more likely to be with robotic surrogates than with biological beings (ch. 26 per *PW*) | **Unverified (speculation).** A view Davies has argued since *The Eerie Silence* (2010); there is no evidence either way | [*THE* review](https://www.timeshighereducation.com/books/whats-eating-universe-paul-davies) | | Today's shift in perspective will be "even more disruptive" than Copernicus's (ch. 1) | **Unverified (opinion);** Clegg calls it hype | [Popular Science review](https://popsciencebooks.blogspot.com/2021/09/whats-eating-universe-paul-davis.html) | Overall, the book's science is mainstream and broadly accurate for a popular primer. I found two dating slips in the chapters I could read: the COBE map's date and the Galileo quotation's year. Two quotations there (Galileo, Jeans) are paraphrased rather than given in the original wording. There is also a loose attribution in the title chapter. Reviewers flag oversimplification of dark matter, spin and the Neptune analogy rather than outright errors. ## 7. Citations and references **The book's own apparatus.** The contents list shows a Preface, 30 chapters and an index (p. 167), with **no endnotes or bibliography**. Figures credit NASA, the Cardozo Kindersley Workshop (fig. 9) and Westminster Abbey (fig. 13). Sources named in the pages I read: Smoot and Hawking on COBE; Churchill; Ptolemy; Galileo (1632 as given); Sir James Jeans; Newton (fluxions; letter on balanced needles); Leibniz. Acknowledged helpers: Cecilia Lunardini, Rich Lebed, Charley Lineweaver, Glenn Starkman, Simon Mitton, Lucy Hawking, Christopher McKay, Pauline Davies, Chloe Currens. **Links used in this dossier.** - Publisher's sample (Allen Lane), via Fnac: https://static.fnac-static.com/multimedia/PT/pdf/9780241459850.pdf - University of Chicago Press book page (blurb, contents, reviews, excerpt): https://press.uchicago.edu/ucp/books/book/chicago/W/bo126163512.html - BiblioVault: https://www.bibliovault.org/BV.book.epl?ISBN=9780226816296 - Penguin UK: https://www.penguin.co.uk/books/319131/whats-eating-the-universe-by-davies-paul/9780141993720 - ASU Beyond Center: https://cosmos.asu.edu/publication/whats-eating-universe - Open Library: https://openlibrary.org/works/OL24490629W ; https://openlibrary.org/works/OL26772986W ; https://openlibrary.org/works/OL28356291W ; cover https://covers.openlibrary.org/b/id/11107379-L.jpg - Google Books (ISBN search): https://books.google.com/books?vid=ISBN9780226816296 - WorldCat (ISBN search): https://search.worldcat.org/search?q=bn%3A9780226816296 - De Gruyter / DOI: https://doi.org/10.7208/chicago/9780226816326.001.0001 - ECU Libraries catalog: https://librarycatalog.ecu.edu/catalog/6792841 - OverDrive: https://www.overdrive.com/media/6089420/whats-eating-the-universe ; https://www.overdrive.com/media/6430189/whats-eating-the-universe ; https://www.overdrive.com/media/6187518/whats-eating-the-universe - Audible: https://www.audible.com/pd/Whats-Eating-the-Universe-Audiobook/0241529271 - Amazon: https://www.amazon.com/dp/022681629X ; https://www.amazon.com/dp/0226823873 ; https://www.amazon.com/dp/0241459850 ; https://www.amazon.com/dp/B08PP73V5K ; https://www.amazon.com/dp/B096L2WP51 - Bookshop.org: https://bookshop.org/p/books/what-s-eating-the-universe-and-other-cosmic-questions-paul-davies/35431a2ff169f087?ean=9780226816296 - Reviews: *Times Higher Education* (Cait MacPhee, 14 Oct 2021) https://www.timeshighereducation.com/books/whats-eating-universe-paul-davies ; *Physics World* (Laura Hiscott, 30 Aug 2021) https://physicsworld.com/a/an-inventory-of-cosmological-mysteries/ ; *Publishers Weekly* (25 May 2021) http://www.publishersweekly.com/9780226816296 ; *Foreword Reviews* (Rebecca Foster) https://www.forewordreviews.com/reviews/whats-eating-the-universe/ ; *Forbes* (Bruce Dorminey, 30 Aug 2021) https://www.forbes.com/sites/brucedorminey/2021/08/30/5-takeaways-when-considering-the-cosmos-remaining-mysteries/ ; Popular Science (Brian Clegg, 3 Sep 2021) https://popsciencebooks.blogspot.com/2021/09/whats-eating-universe-paul-davis.html ; *The Times* review (paywalled, not read) https://www.thetimes.com/culture/books/article/whats-eating-the-universe-by-paul-davies-review-00s9bh89m ; *Wall Street Journal*, "A Pocket Guide to the Cosmos" (paywalled; quoted only via the press page) https://www.wsj.com/articles/whats-eating-the-universe-review-a-pocket-guide-to-the-cosmos-paul-davies-dark-matter-11631292599 ; *100% Rock* (Steph O'Connell, 20 Sep 2021) https://100percentrock.com/2021/09/book-review-whats-eating-the-universe-by-paul-davies/ ; Greek blog (Κ. Βακουφτσής, 15 Mar 2022) https://kostasvakouftsis.blogspot.com/2022/03/whats-eating-universe.html - Interviews and talks: https://www.templeton.org/news/paul-davies-on-whats-eating-the-universe ; https://www.rigb.org/explore-science/explore/video/whats-eating-universe-paul-davies ; https://www.youtube.com/watch?v=08aLgCb56_w ; https://youtu.be/IRHIGzWfG0Y ; https://www.abc.net.au/listen/programs/conversations/paul-davies-the-universe-mysteries-of-the-cosmos/13535374 ; https://physicsworld.com/a/pondering-cosmic-mysteries-with-paul-davies-tandem-solar-cells-could-soon-be-on-your-roof/ ; https://brucedorminey.podbean.com/e/episode-66-the-big-questions-about-the-cosmos-and-our-existence/ ; https://www.findinggeniuspodcast.com/podcasts/cosmic-mysteries-from-aliens-to-cancer-treatments-the-timeless-importance-of-the-study-of-physics/ ; https://iai.tv/video/whats-eating-the-universe-paul-davies - Source video: https://www.youtube.com/watch?v=e41IyOlfj7I - Biography: https://en.wikipedia.org/wiki/Paul_Davies ; https://retractionwatch.com/2025/07/24/science-retraction-arsenic-life-nasa-astrobiology/ ; https://www.nytimes.com/2007/11/24/opinion/24davies.html - Fact-check evidence: https://en.wikipedia.org/wiki/Cosmic_Background_Explorer ; https://www.nytimes.com/1992/04/24/us/scientists-report-profound-insight-on-how-time-began.html ; https://ned.ipac.caltech.edu/level5/March03/Lineweaver/Lineweaver7_2.html ; https://ui.adsabs.harvard.edu/abs/1990ApJ...354L..37M ; https://en.wikipedia.org/wiki/The_Assayer ; https://en.wikiquote.org/wiki/James_Jeans ; https://en.wikipedia.org/wiki/De_revolutionibus_orbium_coelestium ; https://en.wikipedia.org/wiki/Isaac_Newton ; https://www.newtonproject.ox.ac.uk/view/texts/normalized/THEM00255 ; https://arxiv.org/abs/1807.06209 ; https://en.wikipedia.org/wiki/CMB_cold_spot ; https://arxiv.org/abs/1704.03814 ; https://arxiv.org/abs/2112.07699 ; https://arxiv.org/abs/0809.3623 ; https://arxiv.org/abs/0810.5128 ; https://arxiv.org/abs/1012.1995 ; https://doi.org/10.1103/PhysRevD.15.2929 ; https://doi.org/10.1103/PhysRevD.21.3305 ; https://doi.org/10.1016/0550-3213(82)90007-4 ; https://en.wikipedia.org/wiki/Bubble_of_nothing ; https://en.wikipedia.org/wiki/Discovery_of_Neptune ; https://en.wikipedia.org/wiki/Modified_Newtonian_dynamics ; https://www.nobelprize.org/prizes/physics/2011/summary/ ; https://arxiv.org/abs/1804.06768 ; https://doi.org/10.1103/PhysRevLett.61.1446 ; https://doi.org/10.1103/PhysRevD.46.603