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freshnfree
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I am getting confused as to which experiment proved that the speed of light was invariant in a vacuum. At first I thought it was the Michelson-Morley experiment but that does not have a moving observer.
Hi, I have gone to the top of this forum but I am not sure of which sticky thread you are referring to.Dale said:The MM experiment was attached to the earth, so it was moving at some point during the day and year. However, the MM experiment only detected the Isotropy of c. For a more complete account of the relevant experiments you should read the sticky thread at the top of the forum.
Oops, I thought this was in the relativity forum. I have moved the thread. I was referring to the "experimental basis of relativity" thread, but here is a direct linkfreshnfree said:Hi, I have gone to the top of this forum but I am not sure of which sticky thread you are referring to.
We pull a vacuum and do experiments.freshnfree said:how we do we know what light is doing in a vacuum
This is described in detail in the link above.freshnfree said:What kind of experiments?
what type of a scenario?freshnfree said:we cannot create very large vacuums and light travels incredibly fast. i cannot see any specific experiment that refers to this type of scenario.
The scenario I am referring to is one which would show that the speed of light is invariant. So we would have a vacuum and a moving observer and a light wave. Could you please tell me of a known experiment of that type of scenario.Dale said:what type of a scenario?
There are many listed experiments done in vacuum. I don't know what being large or small has to do with anything. Just search with the word vacuum.
freshnfree said:The scenario I am referring to is one which would show that the speed of light is invariant. So we would have a vacuum and a moving observer and a light wave. Could you please tell me of a known experiment of that type of scenario.
Every experiment performed on Earth involves a moving observer, as every point on the surface of the Earth is moving. Do you mean an observer moving relative to the source of the light wave?freshnfree said:The scenario I am referring to is one which would show that the speed of light is invariant. So we would have a vacuum and a moving observer and a light wave. Could you please tell me of a known experiment of that type of scenario.
All of the experiments in sections 3.1-3.4 do that.freshnfree said:The scenario I am referring to is one which would show that the speed of light is invariant.
The phrase "a moving observer" doesn't mean anything because every observer is at rest in one frame and moving in all other frames. I think that you mean "an observer moving relative to the source". This would include all of the experiments in 3.3. Be sure to read the explanation of "optical extinction", which is the key criticism regarding whether an experiment has a good enough vacuum.freshnfree said:So we would have a vacuum and a moving observer and a light wave.
The speed of light invariant in vacuum refers to the constant speed at which light travels in a vacuum, which is approximately 299,792,458 meters per second. This means that the speed of light in a vacuum is the same for all observers, regardless of their relative motion or the direction in which the light is traveling.
The speed of light invariant in vacuum was first determined through the famous Michelson-Morley experiment in 1887. Since then, numerous experiments have been conducted to confirm the constant speed of light in a vacuum, including the Kennedy-Thorndike experiment and the Ives-Stilwell experiment.
The speed of light invariant in vacuum is a fundamental constant in physics and plays a crucial role in many theories and equations. It is the maximum speed at which any energy, information, or matter can travel, and is a key factor in understanding concepts such as special relativity and the relationship between space and time.
Yes, there is overwhelming evidence from various experiments that support the speed of light being invariant in vacuum. In addition to the Michelson-Morley experiment, other experiments such as the Fizeau experiment and the Airy disk experiment have also confirmed the constant speed of light in a vacuum.
According to the theory of special relativity, the speed of light is always constant in a vacuum. However, it can change when traveling through a medium, such as water or glass. In these cases, light can be slowed down due to interactions with the particles in the medium, but it still remains constant within that medium.