Michelson Morley experiment

The question of the possible existence of a nonzero photon rest mass was raised by Einstein [42], Bass and Schrodinger [43], de Broglie and Vigier [44], and further by Evans and Vigier [5], among others. It includes such crucial points as the relation to the Michelson-Morley experiment, and the so far undetermined value of such a mass and its experimental determination. 

Consequently, there should be no noticeable departure in recorded velocity from the Michelson-Morley experiments when the photon rest mass is changed from zero to about 10-39 kg = 10 9me or less. For a photon rest mass in the range... 

Albert Michelson developed the interferometer about 1880 and conducted the Michelson-Morley experiment in 1887, in which it was found that the speed of light is independent of the motion of the source and the observer, this crucial experiment led Einstein to the theory of relativity. Michelson also used the interferometer to create the predecessor of today s length standard based on the wavelength of light. He received the Nobel Prize in 1907 for precision optical instruments and the spectroscopic and metrological investigations carried out with their aid. ... 

At the beginning of the twentieth century, there were several isolated voices claiming for a revision of the Michelson-Morley interpretation. Hicks [52] performed a theoretical analysis of the Michelson-Morley experiment and concluded that data were consistent with a somewhat larger magnitude of the difference of speeds. More importantly, he noted that the data followed a periodic curve proportional to cos 20, where angle 0 refers to a rotation of the interferometer relative to the presumed direction of orbital velocity. The functional dependence present in the results is of the form to be expected if there existed E. 

The most important critic of Michelson and Morley s interpetation was, no doubt, Dayton C. Miller. He was a collaborator of Morley in the work that followed the initial experiments. Miller applied some of the corrections suggested by Hicks [52] to the results of Michelson-Morley experiment. Miller reports that, after the corrections, the difference of speeds measured in the original experiment were 8.8 km/s for the noon observations and 8.0 km/s for the evening observations [53, p. 207] clearly, nonnull results. 

In summary, the only direct evidence against the existence of a preferred frame E is the interpretation of Michelson-Morley experiments as being a nullresult. To put it mildly, this evidence is fairly weak. On the contrary, there is mounting evidence for the existence of local anisotropies [49,59,60], which can be interpreted as motion of the earth relative to E. Additionally, a replication of Faraday induction experiments with a rotating permanent magnet yielded a positive outcome [61]. Such results may be interpreted as an indication of the existence of absolute motion, and hence of E. As usual, the final referee will be empirical evidence. Hence, there is a pressing need to carry out new... 

The photon model here refers to a photon at rest in E. The four theories just mentioned are compatible with Eq. (101). Detailed predictions of each theory are different, so that crucial tests may be designed and carried out. For instance, the Michelson-Morley experiment is conventionally interpreted as a demonstration of Einsteinian relativity, but the evidence is not convincing, as discussed in Section II. Another example, to discriminate between relativistic theories (1) and (2) and emission theories (3) and (4), it is necessary to measure with high precision the velocity of photons with energy higher than 100 keV. 

Numerous unsuccessful measurements were made to determine the motion of earth in the ether. These measurements were not able to give results compatible within the framework of classical Newtonian mechanics, even though that the earth has an orbital velocity v0 30,000 m/s (where v0 is velocity of the earth to the ether). In 1887 Michelson and Morley also determined the earth s orbital velocity by their precision interferometer [11], The updated arrangement of Michelson-Morley experiment (M-M experiment) can be seen in Fig. 1. 

Figure 1. An up-to-date arrangement the of Michelson-Morley experiment. Here LASER means the source of light, BS means beamsplitter, Ml and M2 are mirrors on the end of arms, PD is the phase detector (interferometer), and v is the earth s orbital velocity, which is regarded as the inertial motion for short time periods.

Naturally this coincidence does not mean that the geometric optics added to the classical physics could be used for the exact description of the light propagation since the Michelson-Morley experiment refuted its validity forever. It is evident that there are possible new mathematical definitions for c+ and c instead of the ordinary speed addition mle of the classical physics seen in Eqs. (9) and (11). These can be compatible with the experimental results as well. 

In the spirit of the standing-wave picture of Sagnac-type experiments, this theory needs to recalculate the result of the Michelson-Morley experiment as well. In the M-M experiment there is a new unknown hidden parameter cp, which denotes the speed of light in the direction perpendicular to the earth s velocity. The traveled path of light in the perpendicular arm Xp = 2Tcp [dim X = meter], [where cp is speed of light perpendicular to the velocity... 

The Michelson-Morley experiment is a perfect example of a null experiment, one in which something that was expected to happen is not observed. The consequences of their observations for the development of physics were profound. Having proven that there could be no stationary ether, physicists tried to advance new theories that would save the ether concept. Michelson himself suggested that the ether might move, at least near the Earth. Others studied the possibility that rigid objects might actually contract as they traveled. But it was Einstein s theory of special relativity that finally explained their results. 

The significance of the Michelson-Morley experiment was not assimilated by the scientific community until after Einstein presented his theory. In fact, when Michelson was awarded the Nobel prize in physics in 1907, the first American to receive that honor, it was for his measurements of the standard meter using his interferometer. The ether wind experiment was not mentioned... 

There has also been some controversy as to how the experiment affected the development of special relativity. Einstein commented that the experiment had only a negligible effect on the formulation of his theory. Clearly it was not a starting point for him. Yet the experiment has been repeated by others over many years, upholding the original results in every case. Even if special relativity did not spring directly from its results, the Michelson-Morley experiment has convinced many scientists of the accuracy of Einstein s theory and has remained one of the foundations upon which relativity stands. 

Luminiferous ether—hypothetical medium proposed to explain the propagation of light. The Michelson-Morley experiment made it necessary to abandon this hypothesis. 

American Institute of Physics. Michelson-Morley Experiment [cited April 2003]. . 

Today, interferometers are used widely in the alignment system of lithographic exposure tools for coordinating the movement of the exposure stage. In particular, they have found application in high-precision measurements of extremely small distances, between different objects in the exposure tool. Furthermore, interferometric lithography owes its very existence to the Michelson-Morley experiment. 

Einstein takes Maxwell s electromagnetic theory as the starting point of his analysis. He does not make any reference to the Michelson Morley experiment. 

Selective gradient experiments are model-dependent. They assume a certain possible effect and look for it. That may be a search for a gradient term, or a differential experiment. Indeed, to isolate a particular effect one should have a model and thus all such gradient terms are model-dependent and the dependence sometimes goes much further than expected naively. Due to the Lorentz invariance somewhat below the famous Michelson-Morley experiment is discussed as an experiment of this kind. 

The classical Michelson-Morley experiment and calculability of the fine structure constant... 

Here, we consider as an example a possible problem with an interpretation of a classical version of the Michelson-Morley experiment. In the experiment some pieces of bulk matter were rotated. It was expected that when rotating their linear scale would not change and comparing the light propagation in different arms of the interferometer we can judge whether the speed of light is the same in different directions. 

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