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Some historical experiments that are relevant to [[WSM]]

In 1798 Henry Cavendish conducted a torsion bar experiment to find the value of the gravitational constant. It used the effect of gravitation of masses attracting each other in twisting a wire. By knowing the gravitational constant it is then possible to determine the mass of the earth. The gravitational constant remains one of the least accurately known physics constants to this day.

http://en.wikipedia.org/wiki/Torsion''bar''experiment

Young's double-slit experiment was first performed about 1805 in an effort to resolve the question of whether light was a wave or particle. Young found clear evidence for the wave nature of light, in contradiction to Newton's view that light was made of particles. It uses two very narrow slits that are close together so that a light source coming through them will create two seperate sets of concentric waves which then interfere making a characteristic pattern of alternating dark and light lines in the regions where the waves cancel and support each other.

http://en.wikipedia.org/wiki/Double-slit_experiment

The Doppler effect was first analyzed by Christian Andreas Doppler in 1845 and is the apparent change in frequency or wavelength of a wave that is perceived by an observer moving relative to the source of the waves. For waves, such as sound waves, that propagate in a wave medium, the velocity of the observer and the source are reckoned relative to the medium in which the waves are transmitted. The total Doppler effect may therefore result from both motion of the source and motion of the observer. Each of these effects is analyzed separately.

http://en.wikipedia.org/wiki/Doppler_Shift

The Michelson-Morley experiment was first performed in 1887 and attempted to measure the motion of the earth through the aether. The use of two paths at right angles to each other which would have differently affected the speed of light enables a sensitive interferometer to detect our velocity and was sensitive enough to show at least the earth's motion around the sun, and possibly the solar system motion as well if that existed. The null result was a shocking surprise to most physicists and various aether drift theories were proposed whereby the earth dragged some aether along with it. The problem was reconciling the null result with other results such as the aberration of star light.

Eventually Einstein's special relativity was accepted as an explanation for the result and aether theories were considered to have been disproved. However subsequent to the work of Schroedinger and de Broglie, the Fitzgerald-Lorentz contraction is no longer an arbitrary function thatv attempts to fix the result, but an expected behaviour of matter that is composed of waves. Although Lorentz Ether Theory (LET) has been shown to be an equally valid interpretation of the results, the physics community has shown no interest in changing their minds again.

http://en.wikipedia.org/wiki/Michelson-Morley_experiment

The Trouton Noble experiment was first performed in 1903 and attempted to electromagnetically test the effect predicted to be caused by the absolute motion of the Earth through the aether. In the experiment, a suspended parallel plate capacitor is held by a fine torsion fiber and is charged. An electromagnetic torque is measured due to magnetic forces since the capacitor is moving through the aether. The experiment determines if the passage of the Earth through the aether could be detected using electrical means. The 1903 experiment got a null result with rather primitive equipment, and modern versions have generally had a positive result, meaning that there is a motion relative to the aether.

http://en.wikipedia.org/wiki/Trouton''Noble''experiment

The Kennedy-Thorndike experiment was first conducted in 1932 and is a modified Michelson-Morley experiment in which the path lengths of a split beam are made unequal. A null result would then not be able to be explained by Fitzgerald-Lorentz contraction. However some results are not null although the precision of the experiment is not sufficient for certainty.

http://en.wikipedia.org/wiki/Kennedy-Thorndike_experiment
http://qom.physik.hu-berlin.de/research_kt.htm

The EPR paradox arises in quantum mechanics and leads to very counter-intuitive and paradoxical consequences. It is named after Einstein, Podolsky, and Rosen, who published the idea in 1935. The EPR paradox draws attention to a phenomenon predicted by quantum mechanics known as quantum entanglement, in which measurements on spatially separated quantum systems can instantaneously influence one another. As a result, quantum mechanics violates a principle formulated by Einstein, known as the principle of locality or local realism, which states that changes performed on one physical system should have no immediate effect on another spatially separated system.

However the analysis of EPR experimental results is statistically flawed because results detected by one observer are discarded if the other observer does not have a coincident result and the resulting data is then considered representative.

http://en.wikipedia.org/wiki/EPR_paradox
http://en.wikipedia.org/wiki/Setup''of''the''EPR''experiment

The GHZ experiments are a class of experiments concerning hidden variables in quantum mechanics such as the EPR experiment. Because the experiment only includes data when all aparatus make a successful detection but assumes that the result is representative, it commits a fundamental sampling error. Results detected by one observer are discarded if another observer does not have a coincident result, so any non-locatility of the correlations are a result of statistical bias.

http://en.wikipedia.org/wiki/GHZ_experiment

Sagnac experiment (yet to do)

Silvertooth experiment (yet to do)

Compton scattering (yet to do)

Aberration of starlight (yet to do)


Proposed experiments :

* [[WsmFotondecay]]

* [[WsmFotonTest]]