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Dark Matter and the Dinosaurs: The Astounding Interconnectedness of the Universe by Lisa Randall
estheria's review against another edition
4.0
Only criticism is that at the end she doesn't circle back around and connect her theory with other observations that would support or deny it. She just finally, finally, after chapters upon chapters of already knowing what the theory will be, puts forth her numbers and ends it. Otherwise this book is a refreshing science read. Some rehashing of physics, but none of it excessive or simplistic. Also she randomly throws shade at politicos throughout the book via analogy, which is both awkward and entertaining.
shawnwhy's review against another edition
5.0
fun book about hidden gravity emmiters and how comets are launched from the keiper belt in a ordered way. the meditations on what dark matter could be( un organized thinly distributed matter maybe? or intereaction with another dimension).
astronomer's review against another edition
4.0
When I first heard about this, I thought this was rather absurd. How could you possibly tie two popular, yet completely independent ideas? But then when I began reading it, I realized the author did actually mean to relate them, and not for commercial reasons. And then, a few chapters down, the idea of a relationship between the two made a lot of sense. By the end, I loved the idea!
I think Lisa Randall has done a good job of explaining both concepts to a layman, and to explain how they could be related. I am looking rather forward to hearing about the results of GAIA's experiments
I think Lisa Randall has done a good job of explaining both concepts to a layman, and to explain how they could be related. I am looking rather forward to hearing about the results of GAIA's experiments
phileasfogg's review against another edition
4.0
You take your eye off the universe for a while and when you look back everything's changed. 80% of the stuff is dark matter now, and there's lots and lots of dark energy. And apparently nothing much about the history and structure of the universe makes any kind of sense without factoring in the dark matter and dark energy, which makes you wonder why physicists and cosmologists pre c1980 weren't all in a state of constant bewilderment. Perhaps they were.
Though I've seen it mentioned in astronomy magazines since the 1980s, dark matter is still kind of new to me, and this book contains the first comprehensive account of it that I've read. It's amazing, and exciting, that 80% of the matter in the universe is a complete mystery. Research into it has discovered lots of ways not to detect it, and lots of things that it evidently isn't. In other words, all attempts to directly detect it have failed.
It is, in a nutshell, a form of matter that doesn't interact with light or with the electromagnetic forces; the only force we know it interacts with is gravity. Physicists discovered its existence from the gravitational effect of dark matter on 'light matter', the kind of matter we and the stars and planets and so on are made of. The evidence for dark matter's existence seems fairly persuasive; the alternative is to believe we don't understand gravity as well as we think we do, which seems unlikely. Dark matter seems to congregate in haloes around galaxies, and the best evidence of its existence is the shapes that certain galaxies form after they've collided.
Learning about dark matter, I started to wonder if there could be such a thing as matter that doesn't interact with any of the forces we know, including gravity. I dub it 'ghost matter'. Such matter would seem by definition to be undetectable, even indirectly, as it wouldn't interact in any way with anything we can see. It would test definitions of 'existence'. Given that no experiment could detect such matter, it might be said to be more a subject for metaphysics than science. But if we some day understood matter at a very deep level, we might be able to deduce that it exists, or doesn't.
It also occurred to me that forces other than gravity must act on dark matter, forces that are presumably specific to dark matter and don't affect 'light matter'. Otherwise, there would be nothing to stop dark matter clumping together and forming lots and lots of black holes, which would probably have made the universe very different than it is. The author addresses the idea of 'dark forces', the utterly unknown forces that may interact with dark matter, in a fun speculative chapter which also explores the (small) possibility of dark matter elements, stars, planets and life forms.
Dark Matter and the Dinosaurs argues that periodic mass extinctions may ultimately have been caused by dark matter. The author and her team believe that there may be a thin dense disc of dark matter bisecting the galaxy at its equator. The solar system periodically crosses the galactic equator on its wobbly orbit around the galaxy. When this happens, objects in the Oort cloud are perturbed by the gravitational influence of that dark matter disc, and more Oort cloud objects than usual are redirected into the inner solar system. Thus the frequency of impacts of large objects on the inner planets increases for a time after the solar system crosses the dark disc.
To fully explain this idea to the non-scientist reader, the author has to explain the history of the universe, of the solar system, of life on Earth, and of meteoroid impacts. And of course all about dark matter. The history of the universe is an old story for anyone who's read a few popular science books, but this is a very dark matter flavoured version of that story, a version where the presence of dark matter was a crucial factor in the universe evolving as it did.
She covers the familiar idea that mass extinctions are periodic, and that they are caused by space objects hitting the Earth. This idea, it turns out, is not as certain as I'd believed: only the extinction event that killed the dinosaurs is known for sure to have coincided with a large object hitting the Earth. The fossil record and the meteoroid impact record are both fairly fuzzy. We're pretty sure there have been five mass extinctions, with a sixth in progress; but at this time we can't be sure of the causes of the first four.
I wonder if thorough exploration of the Moon could help solve the question? The meteoroid impact record there is almost perfectly preserved, as the only thing that erases old lunar craters is later craters forming in the same place. If lunar craters can be accurately aged, it should be possible to determine if impacts periodically increase in frequency.
It wasn't a fast read. There was a lot to think about. And I spent too much time trying to unravel sentences committing some error of grammar or usage that garbled their meaning, and railing against the standards of modern publishers unwilling to spend money on proofreaders. When the acknowledgements indicated the book had been proofread, I wondered if the Kindle edition I read might, due to some accident, have been created from a pre-proofread version. Probably this annoys me more than it would other readers, because part of my job is to proofread the often surprisingly unliterate writings of engineers. I can't help but harp on it.
It seems a shame to end on a negative note when this was such a good, thought-provoking, informative book on the cutting edge of exciting science. It's made me want to read more like it.
Though I've seen it mentioned in astronomy magazines since the 1980s, dark matter is still kind of new to me, and this book contains the first comprehensive account of it that I've read. It's amazing, and exciting, that 80% of the matter in the universe is a complete mystery. Research into it has discovered lots of ways not to detect it, and lots of things that it evidently isn't. In other words, all attempts to directly detect it have failed.
It is, in a nutshell, a form of matter that doesn't interact with light or with the electromagnetic forces; the only force we know it interacts with is gravity. Physicists discovered its existence from the gravitational effect of dark matter on 'light matter', the kind of matter we and the stars and planets and so on are made of. The evidence for dark matter's existence seems fairly persuasive; the alternative is to believe we don't understand gravity as well as we think we do, which seems unlikely. Dark matter seems to congregate in haloes around galaxies, and the best evidence of its existence is the shapes that certain galaxies form after they've collided.
Learning about dark matter, I started to wonder if there could be such a thing as matter that doesn't interact with any of the forces we know, including gravity. I dub it 'ghost matter'. Such matter would seem by definition to be undetectable, even indirectly, as it wouldn't interact in any way with anything we can see. It would test definitions of 'existence'. Given that no experiment could detect such matter, it might be said to be more a subject for metaphysics than science. But if we some day understood matter at a very deep level, we might be able to deduce that it exists, or doesn't.
It also occurred to me that forces other than gravity must act on dark matter, forces that are presumably specific to dark matter and don't affect 'light matter'. Otherwise, there would be nothing to stop dark matter clumping together and forming lots and lots of black holes, which would probably have made the universe very different than it is. The author addresses the idea of 'dark forces', the utterly unknown forces that may interact with dark matter, in a fun speculative chapter which also explores the (small) possibility of dark matter elements, stars, planets and life forms.
Dark Matter and the Dinosaurs argues that periodic mass extinctions may ultimately have been caused by dark matter. The author and her team believe that there may be a thin dense disc of dark matter bisecting the galaxy at its equator. The solar system periodically crosses the galactic equator on its wobbly orbit around the galaxy. When this happens, objects in the Oort cloud are perturbed by the gravitational influence of that dark matter disc, and more Oort cloud objects than usual are redirected into the inner solar system. Thus the frequency of impacts of large objects on the inner planets increases for a time after the solar system crosses the dark disc.
To fully explain this idea to the non-scientist reader, the author has to explain the history of the universe, of the solar system, of life on Earth, and of meteoroid impacts. And of course all about dark matter. The history of the universe is an old story for anyone who's read a few popular science books, but this is a very dark matter flavoured version of that story, a version where the presence of dark matter was a crucial factor in the universe evolving as it did.
She covers the familiar idea that mass extinctions are periodic, and that they are caused by space objects hitting the Earth. This idea, it turns out, is not as certain as I'd believed: only the extinction event that killed the dinosaurs is known for sure to have coincided with a large object hitting the Earth. The fossil record and the meteoroid impact record are both fairly fuzzy. We're pretty sure there have been five mass extinctions, with a sixth in progress; but at this time we can't be sure of the causes of the first four.
I wonder if thorough exploration of the Moon could help solve the question? The meteoroid impact record there is almost perfectly preserved, as the only thing that erases old lunar craters is later craters forming in the same place. If lunar craters can be accurately aged, it should be possible to determine if impacts periodically increase in frequency.
It wasn't a fast read. There was a lot to think about. And I spent too much time trying to unravel sentences committing some error of grammar or usage that garbled their meaning, and railing against the standards of modern publishers unwilling to spend money on proofreaders. When the acknowledgements indicated the book had been proofread, I wondered if the Kindle edition I read might, due to some accident, have been created from a pre-proofread version. Probably this annoys me more than it would other readers, because part of my job is to proofread the often surprisingly unliterate writings of engineers. I can't help but harp on it.
It seems a shame to end on a negative note when this was such a good, thought-provoking, informative book on the cutting edge of exciting science. It's made me want to read more like it.
jaclynday's review against another edition
4.0
I am uniquely unqualified to review this book in any substantial way. So, I’ll say then that I loved it, found it fascinating and eye-opening, and enjoyed learning about science and astrophysics from Randall’s conversational, highly-intelligent voice. It’s a dense read—no CliffsNotes—but I appreciated Randall raising the bar for us peasants.
leftylucyprivateeye's review against another edition
4.0
Whew, this book is a lot of fairly dense material for a non-physicist. I'm pretty sure she threw dinosaurs in the title because it sounded cool and more people would pick it up (like me). However, I do know 100% more about dark matter, the standard model of physics and general cosmology than I ever expected!
quigonchuy's review against another edition
4.0
A good book by someone at the forefront of dark matter research. It dragged a bit for me at times, mostly because she goes over things I am already familiar with, but that's not her fault or a shortcoming of the book.
ameliaholcomb's review against another edition
4.0
It took me over a year to read this because I kept putting it down and picking it up again. Some of the content was very dense, making it less appealing to read. However, the book was very well-written, informative, and intriguing.
panthor's review against another edition
3.0
Dark matter: phlogiston/caloric/aether for the modern age. Or possibly the substance in the Ark of the Covenant. Whatever it is (if it exists), apparently nobody (including the author) knows what it is.
socraticgadfly's review against another edition
1.0
Too much science fiction with an icing of scientism
This probably should be filed under science fiction. I didn't realize before I started to read that Randall believes in the periodicity idea of mass extinctions. I know, and have long known, that that's been debunked. Friend Donald Prothero, in his 1-star review at Amazon, has the details.
Beyond Nemesis having been debunked, most of her ideas and claims about the Oort cloud are highly speculative at best.
That's all bad enough for a pretty heavy ding. Then, I saw this clear scientism-type dismissal of philosophy on page 27, and that was the icing on the cake:
"Philosophy, to a scientist at least, concerns questions we expect we will never reliably answer."
Prof. Randall, scientists who actually understand philosophy would cringe at such a definition. That's part of why philosophy of science exists, too.
Even worse? She's a member of the American Philosophical Society.
Finally, there's the subtitle: "The Astounding Interconnectedness of the Universe." Sounds a bit too "breathless," even quasi-New Agey, for me. Yes, book publishers have the final call (theoretically) on titles, but she could have pushed for something different had she wanted.
Suffice it to say I'll not be reading her in the future, either.
This probably should be filed under science fiction. I didn't realize before I started to read that Randall believes in the periodicity idea of mass extinctions. I know, and have long known, that that's been debunked. Friend Donald Prothero, in his 1-star review at Amazon, has the details.
Beyond Nemesis having been debunked, most of her ideas and claims about the Oort cloud are highly speculative at best.
That's all bad enough for a pretty heavy ding. Then, I saw this clear scientism-type dismissal of philosophy on page 27, and that was the icing on the cake:
"Philosophy, to a scientist at least, concerns questions we expect we will never reliably answer."
Prof. Randall, scientists who actually understand philosophy would cringe at such a definition. That's part of why philosophy of science exists, too.
Even worse? She's a member of the American Philosophical Society.
Finally, there's the subtitle: "The Astounding Interconnectedness of the Universe." Sounds a bit too "breathless," even quasi-New Agey, for me. Yes, book publishers have the final call (theoretically) on titles, but she could have pushed for something different had she wanted.
Suffice it to say I'll not be reading her in the future, either.