How does Einstein's theory of special relativity explain MichelMorley experiment? (1 Viewer)
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the MM experiment proved that there was no relative motion to the ether
(since everyone knew the earth was moving this meant the ether didnt exist)
Einstein's Special Relativity theoreticised that the speed of light was constant
to all observers.
Straight away I dont think these two are related? But in another way, since M-M were looking for an interference pattern by 1 of the light beams travelling slower than the other. and If light has a constant speed, then no interference will ever be found even if an ether existed
can someone help out with this? im getting myself confused
(since everyone knew the earth was moving this meant the ether didnt exist)
Einstein's Special Relativity theoreticised that the speed of light was constant
to all observers.
Straight away I dont think these two are related? But in another way, since M-M were looking for an interference pattern by 1 of the light beams travelling slower than the other. and If light has a constant speed, then no interference will ever be found even if an ether existed
can someone help out with this? im getting myself confused
Mat_Aussie
Member
Yeah i see what u mean serge
if the speed of light wasnt constant, they couldnt have performed the experiment.
if the speed of light wasnt constant, they couldnt have performed the experiment.
AntiHyper
Revered Member
I think the MM experiment is tied closely in backing up Einstein's equations regarding to high speeds. To back up his thought experiments (i think it goes "If I was in a train travelling faster than the speed of light and I held up a mirror in front of me, would I be able to see myself?") since the MM experiment contradicted the aether model, Einstein's laws/equations can survive.
Equations such as TV = T0/sqrt(1 - (v2/c2))
Equations such as TV = T0/sqrt(1 - (v2/c2))
How does Einstein's theory of special relativity explain the result of the Michelson Morley experiment? (4)
this is a short answer question in HSC 2001. can someone please help out?
Einstein's theory was developed without knowledge of the MM experiment but it does help explain its results. The theory of special relativity states that the speed of light is constant and that it is self-propagating (read: needs no medium to through which propagate). As was correctly pointed out the MM experiment proved that there was no observed relative motion between the Earth and the supposed aether, Einstein's theory explains this result as it proves that no aether is needed.
this is a short answer question in HSC 2001. can someone please help out?
Einstein's theory was developed without knowledge of the MM experiment but it does help explain its results. The theory of special relativity states that the speed of light is constant and that it is self-propagating (read: needs no medium to through which propagate). As was correctly pointed out the MM experiment proved that there was no observed relative motion between the Earth and the supposed aether, Einstein's theory explains this result as it proves that no aether is needed.
hehe
thanks guyz. so basically, the gist of it is that since the aether was proven not to exist, this supported Einstein's theory of relativity, because light is regarded to be self-propagating. And because no inteference pattern was detected (with one light beam running across and the other against the aether), the speed of light being constant is confirmed to be true. RIGHT?
thanks guyz. so basically, the gist of it is that since the aether was proven not to exist, this supported Einstein's theory of relativity, because light is regarded to be self-propagating. And because no inteference pattern was detected (with one light beam running across and the other against the aether), the speed of light being constant is confirmed to be true. RIGHT?
DigitalFortress
Member
Einstein hadn't heard of the experiment, well he didn't mention it in his 1905 paper on electrodynamics yadda yadda yadda CRAP.
Anyway, isn't the answer to the question that even if the earth was moving through the ether it wouldn't change the speed of light. I don't think he disproved the ether existed he just said it doesn't matter if it DOES exist.
nfi really.
Anyway, isn't the answer to the question that even if the earth was moving through the ether it wouldn't change the speed of light. I don't think he disproved the ether existed he just said it doesn't matter if it DOES exist.
nfi really.
I am afraid not. Einstein proved that the aether did not exist when he proved that the speed of light was constant.
To demonstrate this, let us assume that the aether DID exist, and thus provided an absolute frame of reference. Light travelling in this absolute frame of reference no longer has a constant speed but rather a RELATIVE speed. This is precisely what the MM experiment was trying to measure.
As an example, suppose the Earth was travelling through the aether with speed x. Light fired from the Earth in the same direction would have speed x + c. Light travelling in the opposite direction would have speed x - c. The speed of light would no longer be constant. Another example is located in the Jacaranda textbook which parallels light travelling through the aether as boats across a river, one against the current one across the current etc.
If this still doesn't clear stuff up let me know.
To demonstrate this, let us assume that the aether DID exist, and thus provided an absolute frame of reference. Light travelling in this absolute frame of reference no longer has a constant speed but rather a RELATIVE speed. This is precisely what the MM experiment was trying to measure.
As an example, suppose the Earth was travelling through the aether with speed x. Light fired from the Earth in the same direction would have speed x + c. Light travelling in the opposite direction would have speed x - c. The speed of light would no longer be constant. Another example is located in the Jacaranda textbook which parallels light travelling through the aether as boats across a river, one against the current one across the current etc.
If this still doesn't clear stuff up let me know.
rama_v
Active Member
Actually I think what DigitalFortress was tryign to say was that just because the speed of light is constant doesnt mean that there is no ether, just that theres no need for one (i.e. light's properties can be explained without). The reason for this is because I think some scientists were arguing that the earth was travelling parallel to the ether, and hence no relative velocity change could be measured by the MM experiment. (some experiments today are still searching for the ether in fact as far as I know).Xenocide said:
I point you to this thread:
http://community.boredofstudies.org/showthread.php?t=67952&highlight=ether
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If you define aether as an absolute frame of reference then it is completely imcompatible with special relativity.
Special relativity says that the speed of light in constant. Yet if light travelled through the aether (an absolute frame of reference) its velocity would become relative to the aether and hence variable.
Naturally the aether can still exist if u remove the property of it being an absolute frame of reference, but then what is the point of the aether
This is why the aether can exist, but has now been proved to be superfluous.
Special relativity says that the speed of light in constant. Yet if light travelled through the aether (an absolute frame of reference) its velocity would become relative to the aether and hence variable.
Naturally the aether can still exist if u remove the property of it being an absolute frame of reference, but then what is the point of the aether
This is why the aether can exist, but has now been proved to be superfluous.