Reinventing Gravity: A Physicist Goes Beyond Einstein |  | Author: John W. Moffat
Publisher: Smithsonian
Category: Book
List Price: $27.95
Buy Used: $6.47
as of 9/6/2010 06:48 CDT details
You Save: $21.48 (77%)
New (37) Used (20) from $6.47
Seller: Goodwill BookWorks
Rating:  20 reviews
Sales Rank: 96592
Media: Hardcover
Pages: 288
Number Of Items: 1
Shipping Weight (lbs): 0.9
Dimensions (in): 9 x 5.9 x 0.9
ISBN: 0061170887
Dewey Decimal Number: 530.143
EAN: 9780061170881
ASIN: 0061170887
Publication Date: October 1, 2008
Availability: Usually ships in 1-2 business days
| |
| Also Available In:
|
| Similar Items:
| |
| Editorial Reviews:
Product Description
Einstein's gravity theory—his general theory of relativity—has served as the basis for a series of astonishing cosmological discoveries. But what if, nonetheless, Einstein got it wrong? Since the 1930s, physicists have noticed an alarming discrepancy between the universe as we see it and the universe that Einstein's theory of relativity predicts. There just doesn't seem to be enough stuff out there for everything to hang together. Galaxies spin so fast that, based on the amount of visible matter in them, they ought to be flung to pieces, the same way a spinning yo-yo can break its string. Cosmologists tried to solve the problem by positing dark matter—a mysterious, invisible substance that surrounds galaxies, holding the visible matter in place—and particle physicists, attempting to identify the nature of the stuff, have undertaken a slew of experiments to detect it. So far, none have. Now, John W. Moffat, a physicist at the Perimeter Institute for Theoretical Physics in Waterloo, Canada, offers a different solution to the problem. The capstone to a storybook career—one that began with a correspondence with Einstein and a conversation with Niels Bohr—Moffat's modified gravity theory, or MOG, can model the movements of the universe without recourse to dark matter, and his work challenging the constancy of the speed of light raises a stark challenge to the usual models of the first half-million years of the universe's existence. This bold new work, presenting the entirety of Moffat's hypothesis to a general readership for the first time, promises to overturn everything we thought we knew about the origins and evolution of the universe.
|
| Customer Reviews:
Showing reviews 1-5 of 20
 Do not buy the Kindle edition! March 17, 2009
vivere (Detroit Metro, MI USA)
20 out of 21 found this review helpful
The kindle edition of this book, like all the other science books with math or other symbols offered in the kindle format, leaves much to be desired. There is no indication for superscripts, so that "ten to the power of forty" is presented as 1040, obscuring the context.
It is surprising to me that nobody checks this and the other science books when they are offered in kindle edition. No quality control whatsoever.
In terms of content, the book is wonderful (see other reviews). I also bought the paper version, because of the errors in the kindle version.
A Fabulous Review of Modern Cosmology November 11, 2008
Philip J. Lillies (Moncton, New Brunswick Canada)
18 out of 19 found this review helpful
For amateurs interested in modern cosmology, this book is a fabulous treat. It poses all the problems and offers solutions that are empirically testable. No more dark matter. No more big bang. Wow!
Moffat's solutions derive from "MOG," or Modified Gravity theory. MOG, as Moffat explains, is similar to MOND, a modification of Newton's theory to accommodate observational data, such as the rapid rotation of galaxies. However, where as MOG has background independence as required by Einstein's theory of relativity, MOND does not. String theory does not have background independence either. So in this respect MOG is superior to both of these theories.
MOG eliminates the singularity at the centre of black holes. Hence, there is no event horizon surrounding the final state of a collapsed start, and no singularity at its centre. This nicely solves the black hole information-loss problem treated extensively in a recent book by Leonard Susskind.
MOG neatly handles the miracle of creation problem. No need to posit a big bang that defies the second law of thermodynamics. At the beginning of the MOG universe, both negative and positive time evolve with increasing entropy and cancel out.
MOG does not have dark matter, but instead posits a stronger gravity at the beginning of time than the standard model. The CMB does not need to arise from a big bang at all. In addition, the flatness and uniformity problem is solved by suggesting that the speed of light is not constant, but rather the ratio of G to c is. Hence, if G is stronger, c is faster, allowing all parts of the early universe to communicate.
I found that Moffat's book was best read in conjunction with Lee Smolin's recent book, "The Trouble with Physics." In his book, Smolin praises Moffat as a friend whom he respects for his boldness and originality. Perhaps they will write their next book together.
Fascinating Book November 10, 2008
T. Ohlendorf (New York)
5 out of 5 found this review helpful
I'm loving this book...in plain language, John Moffat writes about the discovery of gravity...the search for alternative gravity theories and for dark matter...he explains dark energy...and writes about the development of MOG (Modified Gravity Theory). The book is also subversive because by telling the story of gravity theory he demonstrates how close-minded the establishment of physics has been (and still is?), and how physicists come to believe ideas just because they are reiterated for decades rather than being proved. Very interesting.
The later sections of the book are somewhat more demanding technically than the early ones (but if you want more challenges Moffat offers footnotes at the back too...). But even if you miss some of the technical details, a sweep of the book allows a fascinating overview of the sociology of science, especially how difficult it is to shift established paradigms. No one yet wants to believe that Einsteins' theory of gravity could be wong! ...Well, this book is a perfect primer for what just might be the future of physics.
The book got me asking questions about some basic ideas that we all have absorbed regarding gravity and the universe. If Moffat's MOG theory continues to stand the test of time, it has a strong chance of replacing Einstein's theory of gravity, which is incredible. This is so exciting and a must read for anyone interested in science.
Alternative to Dark Matter November 15, 2008
J. Waid Baker (Grayling, MI USA)
7 out of 8 found this review helpful
Reinventing Gravity by Moffat is a "must read" for anyone who is thinking about modern physics and the role of gravity in it. To put it simply, Moffat gives a very compelling alternative to dark matter. At the time of this review dark matter is said to compose at least 23% of the universe. However; this substance has yet to be directly detected in any lab and its existence is inferred by the application of General Relativity. In a nutshell; Moffat's book presents what could very well be an answer to the "galactic rotation problem" and a myriad of other conundrums in astrophysics. Further; his revolutionary theory is quite sound and takes a much needed step into a review of the overall correctness of Einstein's General Theory of Relativity.
Other physicists such Milgrom (MOND) and Bekenstein (TeVeS) have proposed changes in the theory of gravity. Moffat's addition of modified gravity (MOG) is another important concept that should not be over looked.
Too many physicists are wedded to the concept of dark matter and refuse to contemplate that just as Newton's theory had to be modified by Einstein that Einstein's theory cannot be the last word. MOG by Moffat is a carefully crafted theory that just might make dark matter obsolete. Dark matter is beginning to appear more ad hoc as time passes and clearly the standard theory of gravity may be at fault. I for one encourage both physicists and non-physicists alike to read this book. MOG, as Moffat presents it in Reinventing Gravity, can be understood by the layman as well as the specialist. It is a theory that makes testable predictions and presents a sound alternative to our present understanding of gravity. Moffat also emphasizes that we must buck the trend" in modern theoretical physics of "indulging in speculations that can never be proved or falsified by reality" by once again developing theories that can be tested.
Reasonable Dissent February 11, 2009
Adam Rourke
4 out of 4 found this review helpful
Einsteins's General Theory of Relativity is one of the crown jewels of human thought. Created in 1915 it quickly became the standard model for understanding gravity. Within the last few years, however, data has begun to accumulate that the theory cannot account for. As an example the speed of the rotation of galaxies is much greater than the theory predicts. To try and fit these latest findings into the present theory scientists have postulated the existence of such things as dark matter. The hunt for dark matter has become the cause celeb of physics and yet to date no one has been able to find it. Within the pages of this book Dr. Moffat argues that the reason that dark matter hasn't been found is that it doesn't exist and that instead it is the theory that is wrong.
This book is Dr. Moffat's way of presenting his ideas to the general public. If he is right in his modified gravity ideas then many things we now take for granted just aren't so, i.e. the speed of light can vary under certain circumstances, there are no black holes, and dark matter and dark energy do not exist. He did his best to keep it simple but remember that this is a physicist's idea of simple. Still all in all he did a pretty creditable job. For science history buffs his recap of the history of gravitation theory is worth a look all by itself. In defending his theory he takes you through all the latest findings, experiments, and theories. If you are interested in physics but know little about it this book is a nice place to start. Weather his modified gravity theory has any merit I am not qualified to say. But in raising the question he reminds us that nothing in science is sacrosanct and that the quest for knowledge never ends.
Showing reviews 1-5 of 20
|
|
|
