On Sun, 24 Aug 2003 11:28:21 GMT, "Painius" wrote:
"Benoit Morrissette" wrote...
in message ...
"Painius" wrote:
"G=EMC^2 Glazier" wrote in message...
...
Ho Painius What reason is given for the photons waves getting shorter
coming towards us,and longer going away from us. I have an idea why this
is reality for light. Bert
Similar to the Doppler effect for sound, Bert . . .
. . .
What i have not figured out yet is how we can make the seemingly
huge assumption that light waves will behave in this manner similar
to sound waves. Any ideas?
Because waves behaves like waves...
In the beginning, Isaac proved that light travels as waves. Problem is that
Albert Einstein proved that light travels as photons. They cannot both be
right, no? Yes, they are, thanks to "mind boggling" quantum dynamic theory...
Sometimes, light behave like waves and other times it behave like photons, just
make sure you don't mix the two together at the same time!
BTW, i am not sure but i think it is Doppler who got the idea for light waves
and Fizeau who got it for sound waves.
Benoît Morrissette
Thanks, Benoît!
Actually, Christian Doppler (1803-1853) *did* get the idea...
for sound *and* for light, yet it was Armand Fizeau (1819 -
1896) who proved Christian Doppler's theory as it applied to
light waves. Here is the story in a nutshell from one of many
similar websites...
Christian Doppler:
The Austrian physicist who developed the famous "Doppler
Effect."
Christian Doppler was an Austrian physicist famous for
devising the "Doppler Effect." Doppler theorized that sound
waves from a moving source would be compressed or
expanded, or that the frequency would change.
The Doppler Effect was used to confirm the Universe was
expanding, also serving an important role in the world of
astronomy.
In 1842, Doppler made the equation about frequency and
relative movement of sound source and observer. Doppler
conducted a unique experiment to prove his theories. For
two days, Doppler had a train pull repeatedly at different
speeds a freight car with trumpeters playing on top of it.
He then had a musician capable of understanding the
differences in sounds record the height of the notes played
as the train moved closer or further away. This effect proved
Doppler's theory superbly. Doppler later tried to prove that
his theory also applied to light but was unable to fulfill his
goal.
Instead, another scientist, Fizeau, generalized Doppler's
work and discovered that the Doppler Effect also applied to
light. This discovery contributed greatly to proving the
Universe was expanding and allowed Doppler's work to
have an important influence on astronomical studies.
-------------------------------------------------------
Now, Benoît... just to say that Fizeau was right simply because
"waves behave like waves" doesn't seem to me to be enough
of an explanation. I like reading your articles because you
usually take the time to make things as clear as possible. So
could you explain how transverse radiation (light, etc.) waves
can be proved to behave just like longitudinal sound waves?
Especially in light of what Odysseus and Bert had to say?
Thanks in advance for your help!
happy days and...
starry starry nights!
Unfortunatly, i am not a quantum physicist so i cannot go further than "waves
behaves like waves"... maybe if we can find the original paper of Fizeau?
One thing i am sure of: we must always be very carefull when we talk about the
dual nature (wave-particle) of light because then we are talking about a
mathematical MODEL, not about light itself. We don't know what light is. No
ones knows. We will never knows. All what we have is a model that describes
adequately all the observations we have so far on the behaviour of light. As
new observations will come by, new models will be built.
We are currently on the verge a a new era in astrophysic: the discovery of dark
energy. Here we have observations that cannot be explained by ANY theory we
have so far. This is the case where a new model of gravitation will have to be
conceived. Some people says that Einstein is right, others says he is wrong.
The real scientist says: I do not know how gravitation works, but it works LIKE
this (so far).
Now, what do we do with dark energy? First, get more observations, a lot more!
Second, create a new model or modify an old one to describe these new
observations. An absolute must for this new model to be accepted by the
scientific community: it must not invalidate any previous observations! Just
like relativity: at low mass low speed, it gives exactly the same results than
newtonian law of gravitation.
Remember: a model do not explain how the universe works, it just describe it.
For the short answer: i cannot prove that transverse light waves behave like
longitudinal sound waves. I don't even know if waves exists really after all...
Benoît Morrissette
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