C= Celeritas (The Speed of Light)
“In light of knowledge attained, the happy achievement seems almost a matter of course, and any intelligent student can grasp it without too much trouble. But the years of anxious searching in the dark, with their intense longing, their alterations of confidence and exhaustion and the final emergence into the light — only those who have experienced it can understand it.”
Einstein’s theories sprang from a ground of ideas prepared by decades of experiments. One of the most striking, in retrospect, was done in Cleveland, Ohio, by Albert Michelson and Edward Morley in 1887. Their apparatus, shown above, was a massive stone block with mirrors and crisscrossing light beams, giving an accurate measurement of any change in the velocity of light. Michelson and Morley expected to see their light beams shifted by the swift motion of the earth in space. To their surprise, they could not detect any change. It is debatable whether Einstein paid heed to this particular experiment, but his work provided an explanation of the unexpected result through a new analysis of space and time.
The deep connection Einstein discovered between energy and mass is expressed in the equation E=mc² . Here E represents energy, m represents mass, and c² is a very large number, the square of the speed of light. Full confirmation was slow in coming. In Paris in 1933, Irène and Frédéric Joliot-Curie took a photograph showing the conversion of energy into mass. A quantum of light, invisible here, carries energy up from beneath. In the middle it changes into mass — two freshly created particles which curve away from each other.
Want to listen Einstein explain the equation? Click here
Or just read the explanation :
“It followed from the special theory of relativity that mass and energy are both but different manifestations of the same thing — a somewhat unfamiliar conception for the average mind. Furthermore, the equation E is equal to m c-squared, in which energy is put equal to mass, multiplied by the square of the velocity of light, showed that very small amounts of mass may be converted into a very large amount of energy and vice versa. The mass and energy were in fact equivalent, according to the formula mentioned above. This was demonstrated by Cockcroft and Walton in 1932, experimentally.”