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In 1905 Albert Einstein was 26 years old. He had a new family and a job as a government patent clerk in Barron Switzerland. It was here that his ideas about physics began to gel and he started to examine questions of light and motion. It's not difficult to analyze motion on earth. And his friend or for reference the juggler on the shore is standing still. While his twin in the boat is moving away from shore at 5 mph. The juggler on the boat also thinks of himself as standing still while the shore and his twin on the shore. Move away at 5 mph. But both twins can describe the movement of the pins in the same way. Motion of juggling is the same for the twins standing on the shore as it is for the twin moving with the boat. And that's the first postulate of relativity. But the laws of physics are the same and all uniformly moving frames of reference. Now Einstein threw light into the equation. He was convinced that no matter how

fast the structure was moving relative to the other each one would still measure the speed of light passing by had to be one hundred eighty six thousand miles per second. But how could that be given their different frames of reference. Simply put speed is the measure of distance traveled in a unit of time. If the speed of light is constant. Einstein thought something else must change. In a flash of brilliance. Einstein asked. What if the speed of light doesn't change. But time does. It was a radical thought and one that was very difficult to accept even for Einstein thought. Could it be that time runs differently for someone moving than for someone standing still. Einstein set out to prove that this could be true. Can we all agree he asked. The two events are simultaneous as they occur at precisely the same time for one of us. They have to occur precisely the same time for all of us. His answer

no. To prove it. Einstein conducted a thought experiment. He imagined placing two poles alongside a train track measuring the distance between them and then marking the center. Using a right angle mirror an observer standing at the center mark beside the train would be able to see both poles at the same time. Now he imagine lightning striking the pole. In the thought experiment. The observer on the ground sees the lightning hit both poles at the same time. To him the events are simultaneous because light travels toward them. From both directions the same distance at the same speed. But how are the same events perceived by the observer moving with the train. He also has a right angle mare. The lightning strikes just as it did before but during the time it takes the light to reach the Observer his frame of reference.

Is closer to the forward pole. This observer sees the lightning strike the pole he is moving toward first. Because the beam of light coming from that pole. As a shorter distance to travel in the beam of light coming from the pole he is moving away from. This would not be surprising by itself. And even be explained by any new theory. But Einstein took the thought experiment further. He took the point of view of the man on the train and figured out how it could have been that the man on the ground received the light from the poles at exactly the same time. In this frame the man in the train is not moving. It's the man on the ground in the polls which are moving along together. The man on the train concludes that the man on the ground would only have seen the lightning strike at the same time if it actually hit the pole. The train is moving toward the forward struck the other pole only then with a light have had time to catch up. With the man on the ground. In time. The two poles were not struck simultaneously in this frame of reference.

Since both frames of reference are equally useful and valid in describing the world Einstein concluded that two events are not simultaneous to all observers. Even if they are to some. And this confirmed Einstein's thought. Time is relative. Just five weeks later on the 30th of June 105 Einstein submitted his findings to a leading German physics journal in a paper entitled On the Electrodynamics of Moving Bodies. In his theory we now call the special theory of relativity. Einstein showed that the faster you move the slower time moves compared to that of a stationary observer he immediately realized and says So already in his first paper the clocks which are moving relative to me must appear to go slower. From my viewpoint. And he even says that if you took a clock round the equator and you had a clock clock at the pole of the earth the one that went round the equator would be going slower than the one at the Pearl you already said that in 1985 as hard as it is to believe.

If you were able to discern the difference you would find the time actually passes more slowly on the drive to school than it does while sitting at your desk. And at greater speeds. Say that 90 percent of the speed of light. The results would be truly remarkable. Time would slow down. And you would shrink to 40 percent of your usual length. From the point of view of the person watching from the side. And here at last was the answer to the question Einstein asked 10 years earlier what would happen if you could ride a beam of light. Nothing. It could never happen because at the speed of light length Rinke to zero. And time stands still. Which at the first glance seems absolutely crazy you would say he's cheating. He couldn't do it that way. And yet when you look at it it is totally and beautifully consistent and it works. That was it. That was the discovery of the Special Theory

of Relativity. Later that same year Einstein applied special relativity to mass and energy and found that E equals MC squared. Which means that the energy contained in any object is equal to the mass times the speed of light squared. And an enormous number. And of mass contains energy. Then Energy has mess every second. The earth is struck by four and a half pounds of sunlight. Who could have thought that a 26 year old patent clerk who worked on physics in his spare time would change forever. Our understanding of the universe.