Why Does E=mc2?: (And Why Should We Care?)

Why Does E=mc2?: (And Why Should We Care?)

by Brian Cox, Jeff Forshaw


$15.98 $15.99 Save 0% Current price is $15.98, Original price is $15.99. You Save 0%.
View All Available Formats & Editions
Want it by Tuesday, November 27 Order now and choose Expedited Shipping during checkout.

Product Details

ISBN-13: 9780306818769
Publisher: Da Capo Press
Publication date: 07/13/2010
Pages: 272
Sales rank: 319,743
Product dimensions: 5.50(w) x 8.10(h) x 0.90(d)

About the Author

Brian Cox, OBE, FRS, is a Professor of Particle Physics at the University of Manchester and the Royal Society Professor for Public Engagement in Science. His many highly acclaimed BBC television documentaries include, most recently, Human Universe and Forces of Nature.

Jeff Forshaw is a Professor of Theoretical Physics at the University of Manchester, specializing in the physics of elementary particles. He was awarded the Institute of Physics Maxwell Medal in 1999 for outstanding contributions to theoretical physics.

Table of Contents

Acknowledgments ix

Preface xi

1 Space and Time 1

2 The Speed of Light 17

3 Special Relativity 37

4 Spacetime 57

5 Why Does E=mc2? 103

6 And Why Should We Care? Of Atoms, Mousetraps, and The Power of the Stars 143

7 The Origin of Mass 171

8 Warping Spacetime 219

Index 243

Customer Reviews

Most Helpful Customer Reviews

See All Customer Reviews

Why Does E=Mc2? 4 out of 5 based on 0 ratings. 55 reviews.
Ladydog More than 1 year ago
Either the equations are messed up or the symbols don't translate correctly in the electronic version. The authors say they are going to explain relativity using math no more complex than the pythagorean theorum and then claim it isn't a book about "maths" when they produce a result without explaining how they got there. At a minimum there should be an appendix showing the calculation. But that isn't the worst part. The authors add symbols without telling you what they are or where they came from. So, on p. 38, the square root of 1/ (c squared - ^ squared) becomes 1/ square root c squared ^ v squared. Huh? Where did v come from? Is it a variable, an operator, what? We don't know because the authors don't say. We know it doesn't mean velocity, because that's what ^ is defined as. Confusing enough, but then further down the same page, the square root c squared ^ v squared becomes ^squared/ c squared, again with no explanation. Thanks for the "maths" lesson guys.
Anonymous More than 1 year ago
They did an exceptional job of presenting this complex topic in down to earth language that explained it far better than any of my physics courses in college.
mumfie on LibraryThing 5 days ago
This is a very clear explanation of physics in a readable format that should be accessible to those with little prior knowledge. Unlike many of its type, it does not stop at E=mc2 but takes us forward to where physics is now, slotting a famous equation into perspective and making it part of a whole voyage of discovery.The authors' joy of physics is also conveyed in a book that bubbles with enthusiasm and excitement and sheer delight in the wonders of discovery. The last couple of pages in particular are uplifting in their celebration of achievement.
nbmars on LibraryThing 5 days ago
This book is yet another popularized explanation of Einstein¿s theory or (as the authors explain) theories of relativity. It is also one of the best available. Its special merit lies in the fact that it actually uses equations. The so-called ¿special¿ theory of relativity defines how observers moving at constant velocity relative to one another observe the same events. The theory begins with the assumption that the speed of light is a constant, no matter what the velocity of the light source. That assumption was originally derived from Maxwell¿s equations of electricity and magnetism and subsequently verified experimentally by the famous Michelson-Morley experiment. From this assumption, the theory concludes that for different observers moving relative to one another, measuring rods shrink, clocks slow down, and the mass of all object increases as their velocity increases. Moreover, these conclusions can be derived with mathematics no more complicated than college algebra and the Pythagorean Theorem. Einstein was troubled by these conclusions. He wanted to know what laws of physics were truly invariant, no matter how different observers moved relative to one another. In fact, he thought the theory of invariance was a better name for his conclusions than the theory of relativity. To make sense of these calculations, which have been verified numerous times by experiment, we must assume that space and time are not separate entities, as we formerly thought, but are inextricably meshed together in a single entity now called space-time. The authors then demonstrate the consequences of the law of the conservation of momentum, expressed in space-time. Remarkably, by teasing the relativity equations regarding length, mass, and time in light of the conservation of momentum, the famous E=mc² pops out almost like magic! The conclusion that energy and mass are equivalent and related to one another in a very precise ratio is completely unexpected and profound. To the authors¿ credit, they do not insulate the reader from the relatively simple math used to derive the theory. The reader¿s appreciation of the profundity of the theory is greatly enhanced by following its mathematical derivation. When it comes to the general theory of relativity, which deals with systems accelerating relative to one another and explains the phenomenon of gravity as the localized curvature of Minkowski space-time, the math becomes much more difficult¿it took Einstein ten years of intense effort to figure it out. I¿ve seen the math in technical journals, and it is far too daunting for the average reader such as me. The authors mercifully omit that math, but point out that the theory ultimately was derived from the observation that objects fall at the same speed (unless differentially affected by air friction). The book also includes a chapter on the origin of mass, which takes us away from relativity theory into the realm of quantum mechanics. The math here is very difficult, but the authors simplify matters as much a possible by using Feynman diagrams. This is a well-written book for the curious layman with a mathematical bent who wants to explore modern physics.(JAB)
travelster on LibraryThing 5 days ago
It is awful to read because the authors speak to you as if you were a child. Find another book on relativity!
gopfolk on LibraryThing 5 days ago
This was a great book for anyone that wants to understand physics just a little bit better. The author takes you through most of the detail of how Einstein came to the conclusion of E=mc^2 without having to walk through the âtough mathâ.Iâve read tons of books like this one but this is worth the read. I was most impressed with the fact that they really did walk you through the concepts without having math harder than the Pythagorean Theorem. If you understand that you can understand this book.The book had took you to the brink of the universe and brought you back to the inner workings of the atomic nucleus. I will be keeping this hard cover book on my bookshelf for years to come.
IslandDave on LibraryThing 5 days ago
Cox and Forshaw have presented a streamlined, focused popular science book aimed at teaching relatively new science readers the basics and history of the famous equation in the title. While experienced physics readers will not likely learn new information, the book offers an approachable description of relativity, how we know it works, and why it is important in the modern world and beyond.While I personally didn't gain much new from this book (as an experienced non-professional physics reader), I believe new readers could be in for a treat. I'd certainly recommend starting a discovery of relativity with this book if the concept seems difficult. The authors take time to explain various concepts and make solid efforts to present reasonable analogies to aid in the explanation. Combined with a singularly-focused subject, the book is an excellent starting point for curious, intelligent readers wishing to know more details about E=mc2. Four stars.
darrow on LibraryThing 5 days ago
A very good introduction to a fascinating subject, worthwhile for novices or experienced readers. In most cases when I found myself asking "... but why?" they provided the answer. My only quibble is that the narrative seems to go off in many different directions; all interesting but not all relevant to the chapter's topic.
Anonymous More than 1 year ago
Anonymous More than 1 year ago
Anonymous More than 1 year ago
Anonymous More than 1 year ago
Anonymous More than 1 year ago
Yes, i DO care, but ppl are saying 'pray for all the lost souls'. Dont get me wrong, i totaly agree, but then OTHER ppl are saying 'shame to the bombers!' And 'i hope the bombers go to h**l!' But please do this: pray for the people of Boston as WELL as the ppl who set off te bombs. U need to forgive them because of the terrible things they did. They were probably innocent alchoholics or something who need to be forgiven. God always forgivs everyone.
Anonymous More than 1 year ago
My aunt uncle and cousins live in boston. Luckily they werent there. People died for no reason AT ALL!~Neon Flash
Anonymous More than 1 year ago
I care A LOT, but as I've said a lot, it's not gun control we need, it's gun owner control. And we don't know if it was North Korea. And peopoe from all over the world come to the Boston marothon, so it's hard to tell who's responsible. I'm wearing purple today, beause I care. The best thing we can do is pray. Prayer is a strong thing. ~In God, ~Your fellow American
Anonymous More than 1 year ago
Anonymous More than 1 year ago
I care because two other tragic things happened this week. There was a shooting in Watertown, MA and some people shot down two MIT police officers. Also, some of my aunts friends and some of my dads collegues were at the finish lie and got hurt. I care because ive been mourning since New Years Eve about death. If you heard about the Watertown and MIT incidents put this symbol somewhere in your post: $. ~Rainbow Dash, Rainbowpaw, and Mintpaw /)(\
Anonymous More than 1 year ago
Anonymous More than 1 year ago
Anonymous More than 1 year ago
Anonymous More than 1 year ago
Anonymous More than 1 year ago
Anonymous More than 1 year ago
Anonymous More than 1 year ago
Anonymous More than 1 year ago