In recent years, a handful of scientists have been racing to explain a disturbing aspect of our universe: only 4 percent of it consists of the matter that makes up you, me, our books, and every star and planet. The rest is completely unknown.
Richard Panek tells the dramatic story of how scientists reached this cosmos-shattering conclusion. In vivid detail, he narrates the quest to find the "dark" matter and an even more bizarre substance called dark energy. The scientists involved in this search--Saul Perlmutter, Brian Schmidt, and Adam Riess--shared the 2011 Nobel Prize in Physics for their efforts.
But these scientists were not all working together. The 4% Universe offers an intimate portrait of the bitter rivalries and fruitful collaborations, the eureka moments and blind alleys that fueled their search, redefined science, and reinvented the universe. Drawing on in-depth, on-site reporting and hundreds of interviews, Panek does for cosmology what others have done for biology, sports, and finance: He tells a fascinating story that illuminates the inner workings of a particular (and in this case, particularly unfamiliar) world.
The stakes couldn’t be higher. Our view of the cosmos is profoundly wrong, and Copernicus was only the beginning: not just Earth, but all common matter is a marginal part of existence. Panek’s fast-paced narrative, filled with behind-the-scenes details, brings this epic story to life for the very first time.
Q: What is the "four percent universe"?
Panek: It’s the universe we’ve always known, the one that consists of everything we see: you, me, Earth, Sun, planets, stars, galaxies.
Q: What’s the other 96 percent?
Panek: The stuff we can’t see in any form whatsoever. At a loss for words, astronomers have given these missing ingredients the names "dark matter" and "dark energy."
Q: What are dark matter and dark energy?
Panek: If you find out, book yourself a flight to Stockholm.
Q: So nobody knows? We're not talking about "dark" as in black holes?
Panek: No. This is "dark" as in unknown for now and possibly forever.
Q: Well, then, what do astronomers mean by "dark matter"?
Panek: A mysterious substance that comprises about 23 percent of the universe.
Q: And dark energy?
Panek: Something even more mysterious that comprises about 73 percent of the universe.
Q: Okay, 73 and 23 add up to 96 percent, which does leave a four percent universe. But if we don’t know what dark matter and dark energy are, how do we even know they’re there?
Panek: In the 1970s, astronomers observed that the motions of galaxies, including our own Milky Way, seem to be violating the universal law of gravitation. They’re spinning way too fast to survive more than a single rotation, yet we know that our galaxy has gone through dozens of rotations in its billions of years of life. Galaxies are living fast but not dying young—a fact that makes sense only if we say that there’s more matter out there, gravitationally holding galaxies and even clusters of galaxies together, than we can see. Astronomers call this substance dark matter.
Q: And the mysterious dark energy?
Panek: In the 1990s, two independent teams of astronomers set out to discover the fate of the universe. They knew the universe was born in a big bang and has been expanding ever since. Now they wanted to know how much the mutual gravitation among all this matter—dark or otherwise—was affecting the expansion of the universe. Enough to slow it down so that the universe would eventually grind to a halt, then collapse on itself? Or just enough that the expansion would grind to a halt and stay there? In 1998 the two teams came to the same conclusion: the expansion of the universe isn’t slowing down at all. In fact, it’s speeding up. And whatever force is counteracting gravity is what they call dark energy.
Q: Do astronomers have any clue as to what dark matter and dark energy might be?
Panek: Yes and no. As for dark matter, they think it might be one of two subatomic particles, but physicists have been looking for these particles for thirty years and still haven’t found them. As for dark energy, they don’t even have an idea of what it might be. They’re still trying to figure out how it behaves. Does it change over space and time or not? If they can answer that question, then they can start to worry about what dark energy is.
Q: If astronomers themselves don’t know what dark matter and dark energy are, why should people believe that they exist?
Panek: Scientists like to quote a saying of Carl Sagan’s: "Extraordinary claims require extraordinary evidence." Many astronomers in the 1970s strongly resisted the idea of dark matter until the evidence became overwhelming. And even the two teams of astronomers that discovered the evidence for dark energy in 1998 resisted the idea until they could no longer come up with another explanation.
Q: Sounds like science is a pretty straightforward process of discovery and follow-up.
Panek: Straightforward, maybe. Pretty, no. As I show in The Four Percent Universe, the discoveries involved a lot of behind-the-scenes rivalries that sometimes turned ugly—rivalries that continue to this day. But in a way, these rivalries have been good for the science. When scientists who would like nothing more than to prove one another wrong wind up agreeing on a weird result, their peers can’t help but take the result seriously. Astronomers hate to say it—they’re as superstitious as anyone else, and they think they’ll jinx their chances—but there are Nobel Prizes at stake here.
Q: So this is real. Astronomers actually believe that 96 percent of the universe is "missing"?
Panek: Yes. They call it the ultimate Copernican revolution. Not only are we not at the center of the universe, we’re not even made of the same stuff as the vast majority of the universe.
Q: What now?
Panek: Nobody knows! And for astronomers, that’s the exciting part. Again and again, at conference after conference and in interview after interview, I’ve heard astronomers say that they can’t believe how fortunate they are to be scientists at this point in history. Four hundred years ago, Galileo turned a telescope to the night sky and discovered that there’s more out there than the five planets and couple of thousand stars that meet the eye. Now astronomers are saying that there’s more out there, period—whether it meets the eye or not. Lots more: the vast majority of the universe, in fact.
Q: If this revolution is such a big deal, why haven’t we heard about it?
Panek: Because it’s just beginning. Only in the past ten years have scientists reached a consensus that what we’ve always thought was the universe is really only four percent of it. Now they feel that figuring out the missing 96 percent is the most important problem in science.
Q: Will finding answers make our lives better? What’s the payoff?
Panek: On an immediate, day-to-day, price-of-milk level, nothing. But Galileo’s observations starting in 1609 completely changed the physics and philosophy of the next four hundred years in ways nobody could have anticipated. As I argue in The Four Percent Universe, this new revolution is going to have the same kind of effect on civilization. The fun is just beginning.
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Most Helpful Customer Reviews
I was aware of the conundrum of the missing matter in the universe; it's a deep puzzle that still has cosmologists trying to figure out where the missing matter is (we know that the universe has to have a certain mass to explain the behavior of objects such as galaxies and galaxy clusters). It seems that ordinary matter (protons, electrons, neutrons and the whole panoply of the wave particles that we are familiar with) represents only about four percent of the matter that must be present in the universe.
Where, or what, is the missing 96%? That's the subject of this fascinating look at the current efforts to understand exactly what is going on. There are a variety of theories; so-called dark matter that we can't detect, dark energy, an even more mysterious hypothetical substance. Lately, there has been some evidence to show that contrary to what we used to believe, neutrinos do actually have a bit of mass. Given their relative abundance, this may help explain the missing mass.
The book is written by Richard Panek,a science writer for the popular press. He's written for magazines such as Discover, and he keeps his easy-to-understand writing style here. He highlights many of the scientists involved, how they've made their discoveries, and what they are doing to get to the bottom of the 21st century's greatest cosmology puzzle.
Highly recommended. This is a breezy, well-written book that will appeal to those lay persons who have an interest in the the large (galactic and otherwise) structures around us. Four-and-one-half stars.
In the first fifty-odd pages, the author introduces scores of scientists, gives their academic history, summaries of the projects they worked on before getting to whatever project they worked on that is actually relevant to the book, the conferences they attended, the papers they published, when they got married, how many kids they had, and so on. Oh, also, it mentions the discoveries that the universe is about 3 Kelvin, and that galaxies don't spin the same way solar systems do, but that's almost tangential.
After the first few chapters, it picks up a little, but not much.
In all, this is a book about people who do scientific research, not a book about science. It goes beyond the pop-science books that make sure to ground the discoveries in the social context straight through to being almost a compendium of mini-biographies. And even if that's what you like, the dry writing style makes it a chore to slog through.
I see that there are a number of reviews here on Amazon, which I think is great. It shows that people care about the big questions-- what's the Universe made of? How do we know?
The review by Paul Preuss is particularly interesting. "Snarky" "virulent" "rancorous" Wow! Who knew science was so much fun?
Preuss doesn't reveal until the 27th paragraph that he is the Press Officer at the Lawrence Berkeley Lab whose job over the past decade has been to press the case for recognition of the work on dark energy done by scientists at his institution. There's nothing dishonorable about putting the best face on the work done by people at the Lab, whether it involves super-heavy elements, the Cosmic Microwave Background, or cosmic acceleration. After all, somebody has to make the case for science in a media atmosphere of Lady Gaga and the cat in the dumpster. But it would be asking too much for a person in his position to give a completely balanced account of a scientific discovery, like the discovery of cosmic acceleration, that took place over time and at many places, as described in the spellbinding new book by Richard Panek, The 4% Universe .
To avoid a similar gaffe, I should tell the reader right up front that I am the same Robert Kirshner referred to in Panek's excellent book. Not always with admiration, but he's not perfect and neither am I. The important thing is that all of the people in this book, and many left out, got to discover something big and wonderful about the universe in which we live. Panek is an excellent guide to that adventure.Read more ›
Most Recent Customer Reviews
I'm only through the first chapter. The book is definitely written for a general audience. I went to high school in the 1960s, so this covers relatively new (for me) territory. Read morePublished 1 month ago by Bureaucrat
This book is remarkable: by far one of the best popular science books I've ever seen, and I've been studying and teaching physics and astronomy for thirty years. Read morePublished 1 month ago by white gold wielder
Good review of the work leading up to the current understanding of the universe.Published 4 months ago by Graham M. Smith
I thought it was pretty good, although I have read some recent books on cosmology Iliked better.Published 5 months ago by Tilden Atwell
Recipient was very pleased with the book. Service was prompt as usual. Thank you very much.Published 7 months ago by Fred Owens
This book really illuminates the persons and personalities of the growth of modern cosmology. I wonder when we will figure out where all the missing matter in the universe is... Read morePublished 7 months ago by Iain A. Brown