Book Review: Why Does E=MC^2?

In the spring of 1905, a twenty-six-year-old unknown clerk (technical expert, second class) in the Swiss Patent Office named Albert Einstein produced a series of four papers in theoretical physics. The first paper was the light quantum paper. The second paper suggested a means to measure the size of atoms using diffusion and viscosity of liquids. The third paper explored Brownian motion using methods of the molecular theory of heat. The fourth paper was an analysis of the electrodynamics of moving bodies that used a modification of the theory of space and time. The whole package was astonishing, but the fourth paper, the relativity paper, challenged Isaac Newton's view of the universe, shocked physics, rattled science, and confused the public so much that Einstein soon became famous as the genius who could be understood by only six people in the whole world.

This last idea was poppycock, since most theoretical physicists understood Einstein without difficulty. The arguments and theory were not difficult to follow. Einstein, in fact, wrote clear theoretical physics, no games, no cleverness, no fancy mathematical punches. All his scientific papers are prime examples of clarity in exposition by a man with no interest in impressing you with his remarkable intelligence. Still, the public could not read the original papers because they were written for physicists who had a common technical language and common mathematical tools. Since the relativity paper essentially produced a revolution in the way science looked at the world, everyone wanted to understand it and know what it meant. During the past century, hundreds of books explaining Einstein's work have been published. Einstein himself tried to help by publishing a popular book with Leopold Infield that remains a classic.

One of the important problems with popularizations of science is that there is not one public, there are many publics, and each public has its own formal education and interest in science. Brian Cox and Jeff Forshaw, two physicists, have managed to produce an account of relativity physics accessible to a wide range of various publics. If you're not a physicist (or not yet a physicist) and you want to understand what Einstein and relativity theory are all about, you would do well to read this book. The writing is clear, sparkling in places, and totally without vanity. Relativity theory, Einstein's supreme gift to us, is at the heart of the way science currently looks at physical reality, and anyone with an adventurous mind should be intrigued by what two smart physicists say about it in plain language.

The last two sentences of this delightful little book reveal it all:

"We walk in the midst of wonders, and if we open our eyes and minds to them, the possibilities are boundless. Albert Einstein will be remembered for as long as there are humans in the universe both as an inspiration and an example to all those who are captivated by a natural curiosity to understand the world around them."

Read this book. It's your world, isn't it? [Brian Cox & Jeff Forshaw: Why Does E=MC^2? (And Why Should We Care?) (July 2009). Da Capo Press.]

Comments

[mergina]

The reason the theory is flawed is because it does NOT take into consideration the mysteries of the universe we have not even begun to fathom.

[frantaylor]

Our GPS system is proof of Einstein's relativity theory. The GPS satellites contain highly accurate atomic clocks. Your GPS receiver can actually measure the changes in the timing signals it receives from the satellites, due to their relative movement. These timing changes are predicted and calculated by Einstein's theory and are used to calculate the position of the receiver.

The Hubble Telescope has been used to measure the bending of rays of light due to the gravitational force of stars, again predicted by Einstein's theory.

The experimental results of the Michaelson-Morley experiment, first conducted in the early 1900's and easily reproduced in any high school physics lab today, cannot be explained without taking into account Einstein's theory.

You should learn more about physics before making such ignorant statements.

Einstein's theory has been verified by so many different techniques that it is one of the most well-proven theories in all of physics.

[PlaceboStudman]

Being something of an amateur arm chair theoretical physicist, my study of Einstein and the theory of relativity was made very simple by, of all things, Star Trek The Next Generation. Basically, the theory E=MC2 says that, as a particle increases speed toward the speed of light, it increases mass, and does so to the point where matter and energy can be interchangeable.


In the ST:TNG series, the Enterprise had several "holodecks" where light was projected and bounced off millions of tiny mirrors. reflected and refracted until it combined to form entities that, when used with force fields could produce a structure with real mass.

Interesting stuff when you ponder that science fiction isn't always totally fiction

[GeologyRocks]

I am more of a lazyboy theoretical physicist than an arm chair one, especially when the theoretical physics involved are ST:TNG related. But as someone who is never likely going to have to measure how long it takes two beams of light to travel from point A to B, assuming that one must pass through the windows of a moving train, while the other was astute enough to make it’s dash without having to encounter 19th century forms of conveyance, I am more likely to spend my arm chair time imagining improvements that should have been built into the holodeck you mentioned in your comment. Why was there not a way for the holodeck program to shut down when someone walked in? Considering how long some of those voyages were supposed to last, I imagine that some people’s holodeck experiences could be potentially embarrassing if others were to walk in and see what was going on.

[PlaceboStudman]

Like every mechanical or electronic device, you had to give it the command. People would often suspend or end the program when the situation warranted a pause in the action. You could delete characters, such as when Riker or Troi tried to delete the characters that Barkley created that resembled Riker and Troi...But the true genius of the holodeck came in when Data played poker with Einstien and Stephen Hawking who made a real guest appearance.

[dgmoffat]

E=MC2 not only applies to a mass speeding up. In the original experiment there was mass that emitted two identical photons in opposite directions so that the mass did not change speed. There was a problem that if you were traveling past the mass just at that time and looked at the mass and the two photons you would think that one photon had higher energy that the other due to Doppler shift which would mean that the mass should be impelled away from the higher energy photon. The paradox was that many observers passing at different speeds and different directions would all seem to see something different and they could not all be right.
The solution was to say that when the mass emitted the photons (energy) it actually lost some mass which balanced the equations for all observers. The amount of mass lost was related to the energy of the photons by E=MC2.