This fascinating book on cosmology straddles the worlds of science and science fiction, addressing questions like the nature of time, e.g. Can it run backwards?, multiple realities and the possibility of the multiverse or infinite universes. Part One, The Nature Of Reality, considers regions of the universe where time may run backwards, infinite realities, wave functions and matterwaves plus a stuff or entity called ortho-positronium. Part Two, The Nature Of The Universe, considers invisible galaxies, stars and planets, mirror matter, the interaction between ordinary and mirror matter, black holes and their significance in the model of the universe, the possibility of intelligent life creating a universe and even how to build a universe. Relativity, quantum physics, the ideas of Hoyle and Chandrasekhar and many others are involved in the speculations. Part Three discusses the likelihood of life on earth having been seeded from space, the comet connection, life as a cosmic phenomenon and the strong possibility of finding alien artefacts on the earth and the moon. The book concludes with a glossary of terms, a reading list with separate headings for Fiction and Non-Fiction and a thorough index. It is a stimulating and thought provoking read written in a manner that everyone can understand. I highly recommend it.

It's hard to decide which idea is stranger--parts of the universe where time runs backward, several different varieties of multiple universes, wandering planets teeming with life, alien garbage piling up on earth . . .. Still, every one of the dozen mind-bending theories Chown describes has been proposed by serious scientists and has at least some scientific value. Chown has interviewed many cutting-edge (and perhaps some over-the-edge) scientists, and presents their findings clearly and entertainingly. Every chapter will make you stop, think and wonder.

Chown is a superb science writer. He's a long-time contributor to the British science weekly, New Scientist, and author of several previous books. He reminds me of Steven Hawking. Both are terse, crystal clear, and are able to explain complex ideas lucidly. Chown is particularly good at coming up with elegant metaphors that cut through to the core of an idea.

It's a quick, informative and exciting read. It deserves two thumbs up in many different universes.

Robert Adler
Science writer, author of Science Firsts: From the Creation of Science to the Science of Creation (Wiley, 2002)

Wow, a fantastically fun book. I'm not sure that I agree with all of the theories it contains-I'm not sure the author even does-but they're certainly astounding and the thought processes that went into creating them is truly awe-inspiring. Some of them are not new to me. What is new, however, is the approachable style of the composition. Although formerly a radio astronomer at Cal Tech, at present Marcus Chown is primarily a professional science journalist. His approach to the topic of modern physics and its newer concepts is one of a writer and broadcaster. As he discusses each topic, he quotes the primary researchers in the field like a writer for Discover magazine would, asking pertinent questions and where necessary, explaining the answers. Through these dialogues with renowned scientists, he allows the reader to become more familiar with the personalities of the individuals at the leading edge of theoretical physics as well as with their ideas. He functions as a very knowledgeable and lucid interface between the professional scientist and the curious lay person.

Each chapter is primarily dedicated to a specific concept having to do with "reality" and with the nature of the universe. Each chapter reads like a well written novel in that the last paragraph serves as a hook to draw the reader on to the next amazing concept in the succeeding chapter. I found that I couldn't just set aside the book. I read it cover to cover in one sitting and loved every minute of it. For those with an interest in but less of a background in physics, there is a fairly detailed glossary in the back of the book which should help with terms, although most are adequately explained in the body of the text. I think that most individuals can understand the concepts as they are explained. It might be a nice place for the junior high student with a strong interest in a science career to become familiar with physics and physicists.

For those who find their appetites wetted for "more,"the bibliography at the back of the book is probably not a very helpful source. Most of the listings are either journal articles that might not be approachable for the average student of the topic or science fiction. Certainly the latter are very good, should one wish to take ones science in a more narrative form. This cast of writers is stellar-no pun intended-and includes Asimov, Clarke, Gunn, Heinlein, and Hoyle, among others. For those who prefer expository style, I'd suggest they check "Just Six Numbers" by Sir Martin Rees, Michio Kaku's "Hyperspace," "Matter Myth" by Gribbin and Davies, and "About Time" by P. C. W. Davies. Each of the latter texts deals more thoroughly with topics addressed in Chown's book by individual chapters.

The title is an allusion to the dream of the alchemists of old who sought a magic kiln in which to transform base metals into gold. That dream remained intact until the discovery in the twentieth century of how the elements are actually built up from hydrogen and exactly what kind of "magic furnace" would be required to turn base metals into gold. In a most engaging narrative, science writer Marcus Chown tells that fascinating story through the lives and ideas of the scientists who made the discoveries.

Chown begins, as one must, with the Greeks and Democritus who opined, "...in reality there are only atoms and the void." Chown shows how it was impossible for the Greeks without the scientific method to go any further than Democritus's intuition. But Chown does not dwell on the alchemy but ratchets us directly to modern science and the growing realization that "Atoms Are Not the Smallest Things" (Chapter Two), and that therefore "it must be possible to transform an atom of one element into an atom of another." (p. 21)

And with that, the race was on to account for how hydrogen became helium which became, through crucibles unimaginable to man, carbon, iron and eventually the heaviest elements. The story culminates in the work of Fred Hoyle, Margaret and Geoffrey Burbidge, and Willy Fowler who explained the nuclear processes operating inside stars and supernovae. Chown finishes with a chapter on the discovery of the cosmic background radiation, the "afterglow of creation" which confirmed how helium was manufactured in the Big Bang, and a chapter on how the elements are strewn into space and end up in Population I stars and eventually in our bodies. There is a Glossary and a Selected Bibliography.

The value of this book lies not only in the fascinating story told but in the magical way that Chown is able to painlessly teach us a little chemistry and physics along the way. I learned more about the nature of atoms and the various forces in nature in these pages, almost incidentally, than I have in any other single book. So intrigued was I in learning more that I turned to the Periodic Table of the Elements as I read the text.

But Chown's style is not didactic. Instead he illuminates the personalities and the flow of ideas. We see Marie Currie with her radiation swollen fingers and Fred Hoyle truant at the back of the local cinema teaching himself to read. We see how the vision of meteorites falling into the sun became the vision of the sun falling in upon itself, shrinking and, as the elements got closer and closer together, heating up, and how that idea coursed after some meandering into the discovery of atomic energy. But perhaps the most beautiful "turn" (as in a poetic change of perception, as in a sonnet) in the book is on page 107 where Chown's writes about the sameness of all the atoms of an element, and then suddenly asks, thinking about the mysterious behavior evidenced by the phenomenon of the half-life: "How could radium atoms all be the same yet behave differently?" This question leads to the uncertainty principle and quantum mechanics.

There is an implicit sense of warning in the book about the limitations of humans doing science. Thus the American geologist Thomas Chamberlain is quoted on page 54 as saying, "There is perhaps no beguilement more insidious and dangerous than an elaborate and elegant mathematical process built upon unfortified premises." He was critiquing Lord Kelvin, but might his words not apply to more recent theories, such as that of one-dimensional strings? And on page 65 it is recounted that Auguste Comte "deemed it self-evident that we would never be able to study" the chemical composition of the stars. Two years after his death in 1857 thanks to the unlikely technique of spectroscopy we were doing just that. Indeed, as Chown reports on page 67, helium was discovered on the sun through a reading of its spectrum before it was discovered on the earth! By the way, Chown's material on spectroscopy is fascinating and helped me to a better understanding of how the process works and how the black lines in spectrums of light reveal the composition of the stars.

Chown has the ability to engage the reader in scientific ideas, perhaps in part because of the unique way he sometimes puts things. For example on page 79 he writes about the resistance encountered by an object as it approached the speed of light. He states, "The only conceivable source of such resistance was a body's mass." However, what I thought was, mass cannot find resistance by itself. There must be something in the very fabric of spacetime that is providing the resistance. It is not enough to posit "inertia" since that really explains nothing. I believe there is still something fundamental that we do not understand about the relationship between the speed of light and the nature of matter and energy.

Chown sometimes uses the language and assumptions of the times he is writing about. For example on page 96 he speaks of "the electrons which flitted about an atomic nucleus like planets round the sun," an analogy now considered somewhat misleading (a "cloud" is preferred, I believe), but in recalling it, we are again forced to imagine what an atom might look like if we could somehow "see" it.

Most amusing story: Austrian physicist Fritz Houtermans making up dreams to tell Sigmund Freud! (p. 110)

Best stream of consciousness leading to insight: Fred Hoyle musing on the atomic bomb project about which he had only second-hand and circumstantial evidence. (pp. 159-160)

Best speculation: In answer to "Where are they?", Fermi's famous question about extra-terrestrials, Chown proposes that they came and went long before the sun even shone. (p. 215)

Probably the clearest exposition of the history of modern nuclear physics. In addition, he ponders some of the great philisophical questions in a realistic way.

I'd recommend it to anyone interested in what we're all actually made of.

I have owned a copy of this book for some time before I got around to reading. And when I did I could not put it down. Marcus Chown spins an enthralling historical account of how we learned about the cosmic synthesis of elements.

My favorite account is about Fred Hoyle's pursuit to solve the riddle of how carbon - the stuff of life - was manufactured in the bowls of stars. The problem was that the thermonuclear fusion of hydrogen to heavier elements could not bridge the gap from beryllium-8 to carbon-12. But Hoyle knew it had to happen because humans existed!

We are carbon-based beings and Hoyle argued that after two helium-4 atoms fused to beryllium-8, a third helium-4 quickly fused to give carbon-12. He calculated that in the bowls of a red giant star the energies of beryllium-8 and helium-4 matched a resonance energy that produced carbon-12. Tests by Willy Fowler confirmed Hoyle's prediction: carbon-12 has indeed the predicted energy resonance! Never, according to Chown, has an anthropic argument been used to make a scientific prediction.

When you start reading this book, make sure you have no other pressing engagements. You won't want to stop reading. Chown has a wonderful, lucid style.

Very little math, but very carefully written. This is the first place to start if you want to get a perspective on the whole range of experiments that led up to the Cobe data. I am particularly impressed with the quality and clarity of the writing. This book is so carefully written that you can actually understand much of the physics involved

This is an excellent book for laypeople about the Cosmic Background Explorer (COBE) satellite, and its discovery of ripples in the radiation from the Big Bang.

Electrons jiggling around generate radio waves. Temperature is just a measure of the average speed with which the atoms of a body are moving, vibrating and spinning. So any body, at any temperature above absolute zero, emits radio waves. Cool!

Why tell you this? Well, when they say the Background radiation is at a temperature of 3 degrees what they mean is, it's of the type of radiowaves that are emitted by a body at a temperature of 3 degrees.

-- and that's something I didn't know, before I read the book.

It's the least of what you'll get:

1. You get a history of the theory.

2. Details about radioastronomy, and how astronomers work around their problems (since everything -- the ground, the air, the dust in the galaxy, the cables on a balloon carrying a detector -- glows with radio waves, it's a bit tricky seeing the backround radiation of the Big Bang)

3. Peeks into how science works: you propose a theory, and then chuck it if it doesn't fit the data, except that sometimes it's the data that's at fault not the theory

4. The importance of confirming your results, so that scientific discovery's a community effort despite all the pushing to get there first

5. The importance of looking at all the ramifications of a theory: gas clouds in interstellar space are warmed by the background radiation, and people measured their temperature, and wondered why they weren't stone cold, long before the radiation itself was observed

6. Why that famous photo of pink and blue patches is both the truth and not

7. Interesting tidbits on cosmology

8. the personalities involved

... and more, and more, in only 170 pages.

Students doing London A Level Astrophysics will find this an exceedingly useful read. (Though no mathematical equations at all, you get a load of physics, painlessly)

And to top it all, some neat rhetoric:

" ... COBE had reached its orbit 900 kilometres above the Earth. It was now circling the Earth every 72 seconds as it turned on its axis. It could be seen in the night sky, going from south to north a little after sunset, or from north to south a little before dawn.

COBE awakened, opening its eyes to the microwave Universe. "

The bit at the end's the best, though.

Read, enjoy, learn.