On 01/28/2010 07:26 PM, Mauro Lacy wrote: > Stephen A. Lawrence wrote: >> On 01/28/2010 03:05 PM, froarty...@comcast.net wrote: >> >>> I have a problem with the M&M experiment. They assume an aether that >>> moves with respect to space yet SR >>> >>> uses a right triangle rule where the spatial rate is assumed to be >>> perpindicular to C. Why isn't gamma considered proof of ether? >>> >> >> The 'ether' has no properties which can be measured, or so it appears at >> this time. Gamma is considered proof that the length and time >> contraction which is described the Lorentz transforms is 'legitimate' or >> 'real' or anyway 'measurable'. However, the assertion that "the >> geometry of space is pseudo-Riemannian with metric signature [-1,1,1,1]" >> is just as useful for describing the conclusion as the assertion that >> there is an ether, and it requires fewer assumptions. >> >> In short, the geometric interpretation of gamma, absent any detectable >> ether dragging, reduces the existence of the ether to an unproved and >> (theoretically) unprovable assumption. Consequently, Lorentz ether >> theory, as an alternative to special relativity, is neither testable nor >> falsifiable and can consequently be said to be not a valid theory. >> >> The ether can't be proved not to exist, of course. But it apparently >> can't be proved *to* exist, either, unless someone comes up with solid >> evidence of ether dragging (which is *not* predicted by LET, Lorentz's >> most mature version of ether theory). > > The Michelson & Morley experiment did in fact detected an ether drift.
It was within the error bars of the experiment; i.e., it was statistically insignificant. So, a "null result" conclusion was appropriate. No experiment ever gets a **zero** result, unless it's done with integer arithmetic! If you check your history you'll find that M&M themselves expected, and WANTED to see, a nonzero result. They were certainly not trying to support relativity -- they were trying to support the prevailing ether theory! They weren't about to brush a real nonzero result under the rug! Yet they interpreted their result as "null" also. One of them -- Morley, I think -- invested a lot of time and effort in redoing the experiment, hoping to see something he'd consider nonzero, with no luck. AFAIK only modern anti-relativists have tried to reinterpret the result as indicating some sort of inexplicable drift, which doesn't match any theory, happened to be statistically insignificant, and the detection of which hasn't been replicated.
