| Topic: |
Science > Physics |
| User: |
"Sam Wormley" |
| Date: |
28 Jun 2007 07:06:46 PM |
| Object: |
Two relativity tests are better than one |
Two relativity tests are better than one
http://physicsweb.org/articles/news/11/6/17/1
28 June 2007
Simultaneous tests of Einstein's special theory of relativity
performed in Europe and Australia have allowed physicists to conclude
that the speed of light is constant in all directions, without having
to make an important assumption that had limited the validity of
previous tests. The researchers performed two different types of
Michelson-Morley experiment -- one on each continent -- which allowed
them to rule out, for the first time, violations of Einstein's theory
that could affect the physical properties of the experimental
equipment and change the outcome of the measurement
(arXiv:0706.2031v1).
Einstein's 1905 special theory of relativity is based on the idea
that the speed of light is constant in all directions regardless of
the relative motion of the observer. A consequence of Lorentz
invariance, this property was first demonstrated by Albert Michelson
and Edward Morley in their famous experiment of 1887.
Michelson and Morley split a beam of light in two and sent the beams
off at right angles to two different mirrors. The beams were
reflected back and recombined to form an interferometer. If the beams
travelled at different speeds in the two directions -- as they would
if they were passing through a stationary aether through which the
Earth was moving -- then the two beams would be out of phase when
they were recombined, leading to an interference pattern. No such
pattern was revealed -- ruling out the existence of an aether -- and
over the past 120 years the Michelson-Morley experiment has been
refined and repeated to confirm that the speed of light is constant
to one part in 10^16.
However, there is one lingering doubt surrounding the
Michelson-Morley experiment, according to Holger Mueller, a physicist
at California's Stanford University. Any Michelson-Morley experiment
is also sensitive to possible changes to the length travelled by the
light, and to changes in the refractive index of the medium that the
light travels through.
Such physical changes could be caused by violations to Einstein's
theory and could prevent the Michelson-Morley experiment from
detecting changes in the speed of light. For example, if the both the
speed of light and the length travelled by a light beam changed by
the same factor, the changes would cancel each other out. Indeed,
such violations are a consequence of some theories that attempt to
reconcile gravity with quantum mechanics -- such as the standard
model extension (SME).
In the past, most physicists simply assumed that the physical
properties of Michelson-Morley experiments do not change, and have
interpreted the results as proof of the Lorentz invariance of light.
Now, however, Mueller and colleagues in Australia, Germany and France
have worked out a way to separate possible changes in the speed of
light from the variations in the physical properties of the
apparatus.
The team performed two different Michelson-Morley experiments \u2013
one in Berlin involving infrared light in optical cavities and the
other in Perth, employing microwave radiation in a pair of resonating
cavities. The research will be described in an upcoming issue of
Physical Review Letters.
The researchers used the SME to calculate possible changes to
physical properties of both experiments as well as to the speed of
light. While the SME predicts that the speed of light in both
experiments should change by the same factor, the theory says that
changes in the physical properties of the two experiments will change
by different factors. By doing two experiments, Mueller obtained sets
of equations that can be solved to separate the possible changes to
the speed of light from physical changes.
Mueller told Physics Web that the experiments were both run for over
a year, which meant his team could measure Lorentz violations that
become evident only by a modulation of the experiment's rotation
relative to an inertial frame, such as the modulation provided by the
Earth's orbit. Making the measurements in different geographical
locations meant that the experiments were sensitive to different
combinations of Lorentz violations, which would boost their ability
to separate the changes.
In all, the team was able to say that Lorentz invariance is not
violated in 14 parameters associated with SME to an accuracy of
around one part in 10^16. While the team were able to boost the
accuracy of some parameters by a factor of 50 over previous
experiments, Mueller believes the real significance of the team's
work is the ability to simultaneously confirm the Lorentz invariance
of light and matter without assuming the Lorentz invariance of the
physical properties of the other.
.
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| User: "Tom Potter" |
|
| Title: Re: Two relativity tests are better than one |
29 Jun 2007 08:53:50 AM |
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"Sam Wormley" <swormley1@mchsi.com> wrote in message
news:q2Ygi.185623$_c5.9257@attbi_s22...
Two relativity tests are better than one
http://physicsweb.org/articles/news/11/6/17/1
28 June 2007
Simultaneous tests of Einstein's special theory of relativity
performed in Europe and Australia have allowed physicists to conclude
that the speed of light is constant in all directions, without having
to make an important assumption that had limited the validity of
previous tests. The researchers performed two different types of
Michelson-Morley experiment -- one on each continent -- which allowed
them to rule out, for the first time, violations of Einstein's theory
that could affect the physical properties of the experimental
equipment and change the outcome of the measurement
(arXiv:0706.2031v1).
Einstein's 1905 special theory of relativity is based on the idea
that the speed of light is constant in all directions regardless of
the relative motion of the observer. A consequence of Lorentz
invariance, this property was first demonstrated by Albert Michelson
and Edward Morley in their famous experiment of ***1887***.
Considering that the speed of light was a constant in
the "Lorentz-FitzGerald contraction hypothesis"
which explained the
"negative result of the Michelson-Morley experiment" in ***1889,***,
it appears more like Einstein hijacked the works of
Lorentz and FitzGerald,
and pretended that he had no knowledge of the
Michelson-Morley experiment which was known by all
physicists of the day,
by asserting that the foundation of his ***1905*** theory
was that the speed of light was constant,
as it already had to be in "Lorentz-FitzGerald contraction hypothesis".
I propose to hijack the Special Theory of Relativity
by stating that the only thing that exists,
and the only thing that can be measured,
between a cause and an effect,
is an interaction time,
and that when the paths between
observers and a specific cause and effect event
are taken into account, that the time interval
associated with a specific cause/effect event
is the same for all observers.
Hmmm!
Come to think about it,
maybe I've also hijacked General Relativity?
http://en.wikipedia.org/wiki/Length_contraction
"The Lorentz-FitzGerald contraction hypothesis, the more formal name for
length contraction was proposed by George FitzGerald and independently
proposed and extended by Hendrik Lorentz to explain the negative result of
the Michelson-Morley experiment, which attempted to detect Earth's motion
relative to the luminiferous aether.
After reading a paper by Heaviside in which was shown that electric and
magnetic fields are deformed by motion, FitzGerald inferred that similarly,
when a body moves through space it experiences a deformation due to motion,
and that this may explain the "null result". FitzGerald suggested the
contraction in an 1889 letter to Science, which remained unnoticed until
Lorentz in 1892 showed how such an effect might be expected based on
electromagnetic theory and the electrical constitution of matter. "
Here's a tip for those who want to
be acknowledged as the genius of the 21st Century,
hijack a common model, and
form a tight friendship with Rupert Murdock.
--
Tom Potter
*** Time Magazine Person of the Year 2006 ***
*** May 2007 Anti-Bigot Award ***
http://home.earthlink.net/~tdp
http://tdp1001.googlepages.com/home
http://no-turtles.com
http://www.frappr.com/tompotter
http://photos.yahoo.com/tdp1001
http://spaces.msn.com/tdp1001
http://www.flickr.com/photos/tom-potter
http://tom-potter.blogspot.com
--
Posted via a free Usenet account from http://www.teranews.com
.
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| User: "Uncle Al" |
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| Title: Re: Two relativity tests are better than one |
28 Jun 2007 08:39:46 PM |
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Sam Wormley wrote:
Two relativity tests are better than one
http://physicsweb.org/articles/news/11/6/17/1
28 June 2007
Simultaneous tests of Einstein's special theory of relativity
performed in Europe and Australia have allowed physicists to conclude
that the speed of light is constant in all directions, without having
to make an important assumption that had limited the validity of
previous tests. The researchers performed two different types of
Michelson-Morley experiment -- one on each continent -- which allowed
them to rule out, for the first time, violations of Einstein's theory
that could affect the physical properties of the experimental
equipment and change the outcome of the measurement
(arXiv:0706.2031v1).
[snip]
In all, the team was able to say that Lorentz invariance is not
violated in 14 parameters associated with SME to an accuracy of
around one part in 10^16. While the team were able to boost the
accuracy of some parameters by a factor of 50 over previous
experiments, Mueller believes the real significance of the team's
work is the ability to simultaneously confirm the Lorentz invariance
of light and matter without assuming the Lorentz invariance of the
physical properties of the other.
Metric gravitation is perfectly predictive within experimental error
in all venues at all scales. So too all theories that wholly contain
it - affine, teleparallel, and noncommutative gravitation. The only
truly interesting experiments observe the disjunction where said
theories conflict: Equivalence Principle, vacuum isotropy, angular
momentum - all in the mass sector *only.* Photons are not diagnostic,
identical composition opposite parity mass distributions *are*
diagnostic.
There are two defining classes of experiments:
1) Relativistic spin-orbit coupling in neutron star binary pulsar
PSR J0737-3039A/B. ~20 years observation.
http://en.wikipedia.org/wiki/Einstein-Cartan_theory
the Boojum
http://arxiv.org/abs/astro-ph/0609417
http://www.oakland.edu/physics/mog29/mog29.pdf
the test bench
2) EP parity violation,
http://www.mazepath.com/uncleal/qz4.pdf
Technicalities; 90 days, ~$350,000.
http://www.mazepath.com/uncleal/lajos.htm#a2
Same rules; two days; about $5000.
Somebody should look. The apparatus is currently furiously doing
nothing instructive other than measuring default null net outputs.
--
Uncle Al
http://www.mazepath.com/uncleal/
(Toxic URL! Unsafe for children and most mammals)
http://www.mazepath.com/uncleal/lajos.htm#a2
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| User: "hanson" |
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| Title: Re: Two relativity tests are better than one |
29 Jun 2007 09:44:33 AM |
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"Uncle Al" <UncleAl0@hate.spam.net> wrote in message
news:468462E2.A4E05A80@hate.spam.net...
Sam Wormley wrote:
http://physicsweb.org/articles/news/11/6/17/1
[Al]
... [for] gravitation ... identical composition opposite parity mass
distributions *are* diagnostic.
There are two defining classes of experiments:
2) EP parity violation,
http://www.mazepath.com/uncleal/lajos.htm#a2
two days; about $5000.
Somebody should look. The apparatus is currently furiously doing
nothing instructive other than measuring default null net outputs.
--
Uncle Al
[hanson]
ahahaha.... So, why aren't any (nor all) of those many NG Einstein
Dingleberries here showing any interest to "look"?... According
to you a miserly $5000 ought to keep them secure in their cozy
warmth near their idol's sphincter. - What are they afraid of?... Or is
that field such a hunger-cloth endeavor that no-one wants to look?
BTW, is "identical composition opposite parity mass distribution"
your new word for Chirality?... ahahaha... Good one! & good luck
Al... and thanks for the laughs.
ahahaha... ahahanson
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