In France during the later half of the 1700's, chemists Monsieur Antoine Lavoisier and his wife Madame Lavoisier made great contributions to the study of matter. Most importantly, they demonstrated that in any transformation, no amount of matter is ever lost and no amount of matter is ever gained. While this law of the conservation of mass did not have the same meaning at the time of its discovery that it did after the discovery of the relationship between matter and energy, it is an essential principle of matter that is used to this day by modern chemists and physicists.
Emilie du Chatelet was an aristocratic French scientist who lived during the first half of the 18th century. She pursued her interests in science and math, and followed the latest developments in physics. One particularly interesting development of her time was the dangerous belief that Newton had a flaw in his studies. By conducting a simple experiment, a Dutch scientist had determined that an increase in the speed of an object would not create an equal increase in the amount of distance it took that object to stop. Rather, an increase in the speed of an object would require a stopping distance equal to the square of that increase. For instance, a car traveling at 20 miles per hour will have a particular stopping distance, x. A car traveling at three times that speed, or 60 miles per hour will have a stopping distance nine times as long, or 9x. This use of squaring to describe the relationship between and object's mass and its velocity was an extremely important development in physics. It became a useful way for scientists to understand the energy of an object and it provided some founding for the squaring in Einstein's equation E=mc².
Michael Faraday was a British scientist who practiced during the 19th century. His contribution to E=mc² is one of the most important because he discovered the connection between electricity and magnetism. Faraday believed that electricity did not simply flow through a wire as was thought at the time. Instead, he proposed that a current of electricity created magnetic forces around a wire. Likewise, when forces of magnetism were moved, they created a flow of electricity. Faraday also theorized that light consisted of this flow of electricity and magnetism. The connection that Faraday found between electricity and magnetism was remarkable. First, it could be used to create kinetic motion, which led to the idea of the motor. Even more remarkably, James Clerk Maxwell, a 19th century British mathematician, performed calculations on electromagnetism that proved that Faraday's suspicions about light were correct. He found mathematically that electromagnetic radiation traveled precisely at the speed of light. This was an incredible discovery because it created a model of electromagnetic radiation.
Einstein took all of the knowledge that scientists before him had gained about matter, energy, and light, and synthesized them into one small formula with huge implications. He made the assumption that no object can travel faster than 670 million miles per hour, or the speed of light. He then theorized that any more energy fueled into an object traveling at the speed of light would not make it go faster, but make up its mass. This means that matter (an atom, for instance) is a dense packet of a tremendous amount of energy. The amount of energy it contains can be calculated by multiplying its mass by the square of the speed of light. In other words, mass can be converted into energy, and energy can be converted into mass. To modern physicists, matter and energy are one and the same.
With Einstein's big idea published, it was ready to be put to use. Lisa Meitner, a Jewish woman living in Germany under the Nazi regime, would do just that. While she faced many hardships and had to leave her university position in Germany to escape the Nazis, her contribution to modern science is significant. She and her colleagues in Germany knew that an atom of uranium had the biggest nucleus yet known. Attempting to make an even bigger nucleus by bombarding a uranium atom with neutrons, their discoveries yielded a strange fact. Barium seemed to be contaminating the sample, yet barium had an even smaller nucleus than uranium. It was Meitner who realized that in fact, the large and unstable uranium nucleus was splitting, and as a result energy was being released that could be predicted with Einstein's equation E=mc². Immediately, and in time for WWII, scientists around the world dedicated themselves to the creation of the atomic bomb.
Einstein's Big Idea was an excellent film. One particularly good quality of the documentary was that it provided a great deal of information in a clear and understandable way. The use of visuals and interviews with scientists and physicists were very informative and helped the viewer understand the ideas in the movie. The film was fairly well organized. While it did jump around a bit chronologically, it provided a thorough break-down of the equation E=mc². The acting was beautifully done. The actors did a great job of giving life to the scientists and their discoveries without overwhelming the documentary's factual message.
The equation E=mc² is a remarkable step in our understanding of the natural world. Its implications are so incredible that even Einstein wasn't sure if it could be true. Yet we have been able to use the energy of matter for better and for worse. Einstein's genius in relating matter, energy, and light certainly earns him the title of the Father of Modern Physics. Einstein's Big Idea is a film that I would recommend to anyone interested in understanding the meaning of the world's most famous equation.
