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on October 19, 2016
Je donne deux étoiles à ce livre non pas pour la validité des informations scientifiques qu’il contient mais plutôt pour la qualité de la vulgarisation de cet ouvrage qui se veut manifestement destiné au grand public.
Les connaissances du lecteur cible sont mal définies ce qui amène l’auteur à changer souvent de niveau d’information: le début d’un sujet est clair et accessible, puis l’auteur survole des aspects plus précis sans les relier d’une manière explicite au sujet principal et sans fournir assez de détails pour qu’on puisse bien les comprendre et en saisir l'importance. En conséquence, on ne retire pas de cet ouvrage une image claire et organisée de l’origine et de l’évolution de l’univers comme on peut le faire à la lecture du récent livre de Christophe Galfard UNIVERS À PORTÉE DE MAIN (L') par exemple.
Il ne faut pas croire les citations sur la couverture qui déclarent par exemple: “Ree’s book is one that even the cosmologically illiterate will be able to understand...”. Je ne recommande pas ce livre comme premier ouvrage sur le sujet car il risque surtout de décourager le lecteur débutant qui pourrait être amené à se croire incapable de comprendre ce sujet trop compliqué et à abandonner sa recherche de réponses à des questions aussi fondamentales.
Il ne faut pas non plus se fier au titre puisque le livre décrit évidemment le commencement et son après. Je suppose que c’est l’éditeur qui a choisi ce titre accrocheur...
Enfin, l’avant-propos de Stephen Hawking, qui fait une petite page, n’ajoute rien au livre sauf le nom de Hawking sur la couverture afin de profiter de sa renommée. Je soupçonne d’ailleurs Rees de l’avoir écrit lui-même et fait seulement signer par Hawking, ce qui expliquerait l’(auto)-dérision à propos du “concept théorique” de Dieu.
Deux points positifs: une bonne petite bibliographie et un index.
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on December 5, 2003
Sir Martin Rees earned his degrees in mathematics and astronomy at the University of Cambridge. Currently he is a professor of astronomy and cosmology and was formerly director of the Institute of Astronomy. He sometimes writes articles for Scientific American and New Scientist magazines.
In this book, Before the Beginning, Dr. Rees touches on many topics of cosmology, established theories and highly speculative subjects such as dark matter, multiverse, and superstring theory, . The book , in my opinion, is not watered-down science as one of the reviewers complains. In his introduction, Dr. Rees informs the reader that he will abstain from using references to deity(s) that lead to more copies being sold and complicated physical formulas that decrease profits. One complaint I have is that the book has no glossary section. Although Rees does describe things like quasars, lambda, and omega, white dwarfs, steady-state theory some readers may not be satisfied with the depth of definitions given within the text.
Anyone who picks up this book must read Chapter 12 "Toward Infinity: The Far Future" in which Rees explains the most likely fate of the Solar System. "In about 5 billion years the Sun will die, swelling up into a red giant, engulfing the inner planets, and vaporizing all life on Earth; it will the settle down as a slowly fading white dwarf. At about the same time the Andromeda Galaxy , already falling toward us, will merge with our own Milky Way." He also speculates as to what would happen if the universe expands forever or collapses according the Big Crunch Theory. How life will have to adopt to this new environment...
Overall, the book is a great read for an amateur interested in cosmology. However, those with no prior experience may become stressed understanding some of the concepts laid out in the book.
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on June 27, 2003
Before the Beginning is one of Sir Martin Rees best endeavors in unraveling the concepts of cosmology for the average reader. As Royal Society Professor at King's College, Cambridge--succeeding Fred Hoyle to the privilege--and Astronomer Royal of Great Britain, his research spans the breadth of astrophysical research, including issues about cosmology, galaxy formation, black holes, and high energy processes like gravitational waves.
While his participation in the forefront of research gives Martin Rees eminent credibility, his ability as a writer gives him great accessibility as well. I am not really a math-physics person, although I enjoy this type of popular work on physics and cosmology and read extensively in the genre. I found this title to be thoroughly understandable. I was lost somewhat in the final chapters of the book especially "How Constant are Nature's 'Constants,'" but pulled more out of the material after rereading it a couple of times. I think that most readers of a skill level of high school and above will understand the material. Even precocious junior high students with an interest in the topic should be able to comprehend much of it.
The author is very methodical in his approach to his topic, introducing it from the point of view of the history of original thinking and research in the field. He gives credit to each participant in that history, even those whose failed attempts have put others on the right path to discovery. He is especially complimentary to Fred Hoyle, who while he helped to create and thoroughly supported the concept of the Steady State Universe, was open minded enough to actually supply some of the tenants of the Big Bang as well. Much is made of the collective contributions of workers in the field, even those who "almost ran." Most important, credit is given to Russian contributions that had been ignored, minimalized, or denied during the Cold War years. By approaching his topic from an historical vantage point, Rees helps the reader to think much the way the discoverers did as they added each additional piece of information to the body of cosmological research as it stands today. While much of actual physics is a plethora of numbers and intricate mathematics even more of it, especially in cosmology, involves logical and creative thought.
From an instructional stand point, the book might be a good way of introducing high school science students to the manner of thought of scientists, to the ideal professional relations between them, to the step by step cumulative logic of this type of thought, and to the actual product of scientific effort.
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This fascinating book deals with inter alia pregalactic history, black holes, dark matter, time in other possible universes, ecology of universes, omega and lambda, great attractors, pulsars, neutron stars and anthropic reasoning, which the author defends. It represents a drastic enlarging of our cosmic perspectives - the cosmos is more spectacular by far than we could have imagined. He also believes that the apparent fine-tuning that our existence depends on cannot be a coincidence. What we call the universe is likely to be just one member of an ensemble, but ours may be in an unusual subset that permits complexity and consciousness to develop. Our universe could be an atom in an infinite collection, a cosmic archipelago in which impassable barriers prohibit communication between the islands. Quoting scientists like Hawking, Chandrasekar and others throughout, the author broadens our understanding of cosmology and quantum science while offering unique and interesting new perspectives on our views of consciousness and existence. Highly recommended.
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on September 6, 2002
The first chapters of the book are a summary of 'The first three minutes' by Steven Weinberg and 'A brief history of time ' by Steven Hawking.
Thereafter, this work becomes a very exciting read.
It deals with the origin of the universe that was created ex nihilo (zero energy), the evolution of the universe (with a first millisecond as an eventful era, and the first 10-36 seconds as an inflationary expansion).
Like John Barrow, he is pessimistic that a 'Theory of Everything' will be found. We don't know the physical laws that prevailed at the Planck time. More, the particles and forces in our universe could be inherently arbitrary. He states that the multiverse may be governed by some unified theory, but each universe may cool down in a fashion that has 'accidental' features ending up ruled by different laws and different physical connstants. His hope to find it lays with the theory of superstrings.
A fundamental question remains the nature of black matter (90 % of the matter in the universe).
On the quantum level, he explains that some processes in the microworld 'know' the direction of time and that there could be a link between consciousness and quantum mechanics.
Importantly,he also states that there is more than one chance in one million that, within the next 50 years, the Earth will be hit by an asteroid large enough to cause worldwide devastation.
A must read for everybody interested in what happened 'before the beginning'.
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on June 21, 2002
This is a terrific book, which covers a whole range of astronomical phenomena. Black holes, the big bang, the big crunch, the multiverse, dark matter, etc. Interestingly, dark matter isn't as spooky as it sounds - it only refers to things in the universe we can't see because they aren't bright enough - objects such as planets.
Although I accept the astronomical evidence for the expansion of the <known> universe, this man will tell you that the whole universe was originally the size of a single pea. I'd like to know how these people can have the audacity to extrapolate to the extreme like this. If my professor saw me doing that with one of my graphs, he'd scream! How can they know PRECISELY what happens in the first yoctosecond after the big bang?! They can only do that if they know everything. Real scientists will admit that they don't know everything. A true scientist will tell you that once you're in extrapolation territory, you're also in uncertain territory. What will most likely happen is that people will discover that the current model of condensed matter physics was merely an approximation, and suddenly the whole notion of a universe the size of a pea will be outdated.
For all those out there that think everything can and will be determined, you might like to know that there is such a thing as the "n-body problem". It states that for more than 3 bodies (be it planets or stars), with an initial position and velocity, it becomes extremely difficult to know their subsequent motion, because of the gravitational influence that each of the bodies exerts on all of the other bodies. Basically, it takes the greatest supercomputers on Earth just to predict the eventual motion of the nine planets in our own solar system. And you know there are approximately 10,000 billion billion stars in this universe.
Martin Rees talks of a multiverse, which is kind of like a load of bubbles, and we exist inside one of them and the edge of our known "universe" is the wall of the bubble. That would mean that we aren't even aware of the other bubbles. If something like a big crunch happens to our bubble, then there are still all those other bubbles that will continue to exist. I think this idea is sensible, because humans have always underestimated the size of "their" universe.
Overall a great introduction to cosmology.
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on April 1, 2002
Sir Martin Rees is Astronomer Royal. How he managed to obtain this lofty position while maintaining his ability to speak English is beyond me. Like Carl Sagan and Lynn Margulis, Sir Martin is able to explain some rather complicated and complex ideas in small, easily managed chunks. He has the ability to entertain us, like Michio Kaku, while at the same time, imparting us with a lasting understanding of many of life's really big questions. I have read perhaps 3,000 books (mostly science based) in my tenure as resident of this planet and have written several. I have also written dozens of book reviews for various media. However, the concepts put down in Rees book flow quite eloquently, positively, and manageably---which is indeed rare. The difference between this book's take on such things as life in the universe, black holes, and the beginning of time are easily set part from their Pseudoscientific counterparts---they make perfect sense. I would like to say that "if you buy one book on cosmology this year--buy this one." But I wont. Simply pick up a copy, thumb through a few chapters and it will sell itself. This book is a must read for any high school student who believes physics or science are boring. Or, for the adult non-scientist that has a desire to know. I gave this book "5 stars" because "6" was not an option. Even I gleaned a bit of education-and that's never a bad thing. A definite MUST own.
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on August 26, 2001
This book is very well written, but to get the actual Planck time value of 5.3906*10^-44 seconds, I had to do a web search. The formula of Sqrt(G*hbar/c^5) wasn't in the book either... in fact the book almost entirely lacks formulas of any kind. I suppose this is very good if you are writing for 6th graders who have to look up the big words, but that makes this not an adult book at all, no matter how well written and how eminent the scholar that wrote it. Cosmology is a subject where all of science comes together in a �big picture�, but the details are very important as Dr. Rees explains. Just how they are important seems to be beyond our understanding? Only in a world where papers by Cambridge scholars are either totally unreadable with jargon or dumbed down beyond any real use! Dr. Wheeler still includes mathematics in his books, thankfully!
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on March 30, 2001
This book is a strong introduction to several major astronomical concepts. It covers a lot and is at times a little disorganized but is well written, clear and stimulating. It is accessible to the novice but its preciseness and density enables to acquire more advanced than just basic knowledge. It could use a 2nd edition by now though, as some of the topics have been the subjects of recent discoveries such as the theory of "brown dwarves". What the reader will definitely not learn is what happened "before the beginning". Nobody knows that and the title is deceptive in that way. I believe Rees meant it as opposed to the biblical "In the beginning...". In the absence of evidence, Rees seems to refuse to even consider that Humanity might have been planned before or at the big bang. To his credit, he seems perfectly content to study and write books about the multiverse in a world before there was a bible, before there was a "In the Beginning...". Hence the title. Rees makes too much of a point of it though, probably to differentiate himself from other popular astronomers.
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on March 5, 2001
Martin J. Rees presents us with a biography of our home, the cosmos. He shows us the coincidence that has happened for the complexity of our life to evolove on this planet. He seems also doubtful that it has happened anywhere else, but that this might be explained naturally by the multiverse, (chances are greater with more universes evolving) rather than the Anthropic Principle. Well, he thinks that we should properly term it "Anthropic Reasoning." And this is a theory he seems a bit regretful of. (doesn't think interface with philosophers and theologians is, in principle, and different from what it was in Newton's day) "It would be a pity if theoretical physicists took anthropic ideas too seriously, as it might diminish their motivation for seeking unified theories." And he does talk a good deal about these unified theories, the relationship with quantum effects and general relativity, and even briefly introduces the reader to super-strings. Also educates us on the niche of other empyreal phenomena like dark matter and black holes, and how every one of the things I'm mentioning relates one to another. He discusses the Big Bang, why we are sure of its validity, and its other implications, which includes the future, our universe's Eschaton. This book is a decent look at the state of Cosmological studies and some of the methodologies of observing this grand and bizarre place that emerged almost ex nihilo.
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