why speed of light is constant to ebery frame of reference
Answers
Answered by
1
That the speed of light should be independent of motion was most surprising. Einstein even felt the need to make it a separate postulate:
"light is always propagated in empty space with a definite velocity which is independent of the state of motion of the emitting body", adding that this is "only apparently irreconcilable with the [Principle of Relativity]”.
The reader should pause to appreciate how strange is this statement. It makes no sense for a light beam – or anything, for that matter – to travel at the same speed regardless of the motion of the observer. Suppose, for example, that you are observing a very fast train from another train. The apparent speed of the fast train would clearly depend on its direction relative to yours. If the other train is moving in the opposite direction, it would go whooshing by, but if it is moving in the same direction, it would pass very slowly. Yet Michelson, a passenger on a train called earth, found that another train called light always moves at the same speed no matter which way earth is moving.
If the M-M experiment had been performed only once, there would have been no problem. We could have simply said that this is the frame of reference in which the laws of physics hold — in which Maxwell’s equations apply and light travels with velocity c. But the result was always the same, regardless of earth’s motion. It is not possible for light to travel with the same velocity in all of these frames of reference unless “something funny” is going on.
"light is always propagated in empty space with a definite velocity which is independent of the state of motion of the emitting body", adding that this is "only apparently irreconcilable with the [Principle of Relativity]”.
The reader should pause to appreciate how strange is this statement. It makes no sense for a light beam – or anything, for that matter – to travel at the same speed regardless of the motion of the observer. Suppose, for example, that you are observing a very fast train from another train. The apparent speed of the fast train would clearly depend on its direction relative to yours. If the other train is moving in the opposite direction, it would go whooshing by, but if it is moving in the same direction, it would pass very slowly. Yet Michelson, a passenger on a train called earth, found that another train called light always moves at the same speed no matter which way earth is moving.
If the M-M experiment had been performed only once, there would have been no problem. We could have simply said that this is the frame of reference in which the laws of physics hold — in which Maxwell’s equations apply and light travels with velocity c. But the result was always the same, regardless of earth’s motion. It is not possible for light to travel with the same velocity in all of these frames of reference unless “something funny” is going on.
Answered by
0
Because it arises from the Maxwells equations of electromagnetism. From here, if you assume that the laws of physics are valid in every reference frame, you can or must see that light is everywhere.
Similar questions