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Reinventing Gravity

A Physicist Goes Beyond Einstein

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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.

From Publishers Weekly

Jul 21, 2008 – Gravity has long been the problem child of physics, creating difficulties in finding a Theory of Everything. To complicate matters, most scientists believe that there is a mysterious, unidentified “dark matter” that makes up most of the universe, and that an equally baffling “dark energy” is pushing the universe apart. Moffat, an affiliate member of the cutting-edge Perimeter Institute for Theoretical Physics in Canada, has developed a new theory that he calls Modified Gravity (MOG). Moffat says that both Newton and Einstein were wrong, and that Newton’s gravitational constant is not constant across distances as large as galaxies and galaxy clusters. Scientists haven’t been able to find dark matter because it doesn’t exist: MOG values help account for rates of galaxy rotation. Perhaps more revolutionary is Moffat’s claim that black holes don’t exist either. His theory predicts a “grey star,” a massive object with many but not all of the properties of a black hole. Moffat’s theory thus far has withstood many objections. If MOG stands the test of time, Moffat will have created a paradigm shift not seen since Newton. Illus.

Customer Reviews

Great read

I read this book a couple years ago. Not being a fan of dark matter being the complete answer to the current problems we have with the theory of gravity I jumped on the chance to read this book. This is still on of my favorites to go back to again and again. Mr. Moffat writes an advanced look at the other possibilities for a complete theory of gravity. Some of which paralleled my own studies. He tries to simplify his work as much as possible, without loosing the complexity of his research. A must read for anyone who wants a deeper understanding of the possibilities and wonder that this single force contains.

Reinventing Gravity
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  • $7.99
  • Available on iPhone, iPad, iPod touch, and Mac.
  • Category: Physics
  • Published: Oct 06, 2009
  • Publisher: HarperCollins e-books
  • Seller: HarperCollins
  • Print Length: 288 Pages
  • Language: English
  • Requirements: To view this book, you must have an iOS device with iBooks 1.3.1 or later and iOS 4.3.3 or later, or a Mac with iBooks 1.0 or later and OS X 10.9 or later.

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