Anthony Mato**** wrote:
> TMA wrote:
>> The only example of perpetual motion in nature is the
>> electro-magnetic wave.
>
> Maybe not even that. A physical object, such as a speeding
> bullet, loses energy and slows down due to friction in the
> atmosphere. Perhaps electro-magnetic waves experience a
> kind of ether friction and lose energy as they pass through
> space. Light waves losing energy would show as red-****fted
> so the more distant an object (star or galaxy) is in space
> the more energy the light would have lost getting here and
> the more red-****fted it would appear.
>
> Anthony
Actually they don't.... however photons can lose energy
to to the cosmic expansion of the universe.
Tired light --- has just failed two crucial tests
Ref: Volume 292, Number 5526, Issue of 29 Jun 2001, p. 2414.
Copyright © 2001 by The American Association for the Advancement of
Science
ASTROPHYSICS: 'Tired-Light' Hypothesis Gets Re-Tired
Charles Seife
The "tired-light" hypothesis, mainstay of a dwindling band
of contrarians who deny the big bang and its corollary, the
expanding universe, has suffered a one-two punch.
Observations of supernovae and of galaxies provide the best
direct evidence that the universe is truly expanding and
promise to shed light on the evolution of galaxies to boot.
"The expansion is real. It's not due to an unknown physical
process. That is the conclusion," says Allan Sandage, an
astrophysicist at the Carnegie Observatories in Pasadena,
California, and leader of the galaxy study.
It's a conclusion that most astronomers reached long ago. In
1929, Edwin Hubble announced that light from distant
galaxies is redder than light from nearby ones. Hubble and
others took the red****fts as evidence that the universe is
expanding, causing distant galaxies to speed away faster
than nearby ones. To an observer on Earth, they reasoned,
this would appear to stretch the wavelength of their light,
just as the sound of a police-car siren seems to drop in
frequency as it speeds away. However, within a few months of
the publication of Hubble's paper, astrophysicist Franz
Zwicky came up with an alternative explanation: that
galaxies' light reddens because it loses energy as it p*****
through space. In Zwicky's tired-light scenario, the
universe doesn't expand at all. Distant galaxies are red not
because they are moving, but because their light has
traveled farther and gotten pooped along the way.
Beyond the fringe. "Tired light"--a radical alternative to
the standard expanding-universe model of the cosmos--has
just failed two crucial tests.
When experimenters first measured the cosmic microwave
background more than 30 years ago, they found that the
radiation was too dim to be explained by Zwicky's
hypothesis. That realization relegated "tired light" firmly
to the fringe of physics, but scientists still sought more
direct proofs of the expansion of the cosmos.
Two new papers provide the best direct evidence yet. The
first, slated to appear in Astrophysical Journal, measures
the brightening and dimming of a certain type of supernova.
Thanks to Einstein's theory of relativity, if distant
supernovae are speeding away from us, they will appear to
flare and fade at a more leisurely pace than close-by ones.
A team of scientists led by Gerson Goldhaber of the Lawrence
Berkeley National Laboratory (LBNL) in Berkeley, California,
has shown that this is, indeed, the case with 42 recently
analyzed supernovae. "It's such a clean-looking curve," says
Saul Perlmutter, a member of the LBNL team. "It's very
unambiguous."
In the second study, Sandage and Lori Lubin of Johns Hopkins
University in Baltimore analyzed space-based measurements of
the surface brightness of galaxies. Both the standard
expanding-universe and the tired-light theory, they
realized, agree that red****fted light should make distant
galaxies look dimmer than they really are. In an expanding
universe, however, time dilation and other relativistic
distortions will also dim distant galaxies, making them
appear much fainter than tired-light theory dictates. What's
more, young stars--and thus young galaxies--tend to be
considerably brighter than old ones. When that extra
brightness is taken into account, the observations match
expanding-universe predictions, as Lubin and Sandage will
re****t in Astronomical Journal. For the tired-light theory
to be correct, young galaxies would have to be dimmer,
rather than brighter, than old ones. "There's no way to
explain that," says Lubin.
Although not surprising in themselves, the results are
useful for "tidying things up in our cosmology," says
Michael Pahre, an astronomer at the Harvard-Smithsonian
Center for Astrophysics in Cambridge, Massachusetts, who
performed a similar surface-brightness experiment in the
mid-1990s. By comparing the expanding-universe theory's
predictions with observed values of the surface brightness
of distant galaxies, scientists can work backward and figure
out how much brighter those galaxies must have been earlier
in the history of the universe.
Even so, researchers doubt whether the results will convert
tired-light diehards. "I don't think it's possible to
convince people who are holding on to tired light," says Ned
Wright, an astrophysicist at the University of California,
Los Angeles. "I would say it is more a problem for a
psychological journal than for Science."
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