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"Art Unwin" wrote
...
On May 6, 7:05 pm, Cecil Moore wrote:
Art Unwin wrote:
I don't know about waves but my understanding is that all colors come
from the mixing of the three basic colors, or is it four?

That's the RGB standard designed for fooling human
eyes into seeing more than just red, green, and blue.
Photons in nature come in *all* EM frequencies.
--
73, Cecil, IEEE, OOTC, http://www.w5dxp.com

Cecil
Seems like this thing called photon is the magic article that created
the big bang.
You attribute everything to the photon but I don't think physics as
got a proper handle on it! Heck, only a few years ago they said a
particle could exist without mass.If a particle emitted from the Sun's
boundary( lepton?) deaccellerated in a particular medium
and broke apart into many electrons, then would not heat or light be
emitted as kinetic energy contained in the particles of different
sizes representing the spectrum
of a particular color with respect to potential energy contained in
the various sized particles? Does your photon come in different sizes,
color and potential energy?
My understanding is that there are about seven leptons that break away
from the Sun's boundary, three of which contains color attributes
along with other flavours which is indicative of temperature and
change in momentum.
I think it is to early to argue about such a subject.

May be it is time to return to the beginning. To the Hertz experiment. See:
(http://people.seas.harvard.edu/~jone...Hertz_exp.html

What and from radiated?
1. Maxwell's waves from the big sparks (the big sparks are in full analogy
to lightning which also radiate radio waves),
2. Electric waves from the two plates (there appear and disappear a huge
charges - electrons are compressible and have mass),
3. Photons
S*

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Szczepan Bia³ek wrote:
Heck, only a few years ago they said a
particle could exist without mass.

Photons have zero *rest* mass. If they had mass at
rest, they could not travel at the speed of light.
The mass of a photon is due to its velocity, c in
free space. When a photon slows to less than the speed
of light in a medium, it gives up its energy to another
particle, e.g. an electron, and disappears.

3. Photons

EM radiation from amateur radio antennas is photonic.
RF energy is supplied to the antenna system by our
transmitters. Free electrons are accelerated and
decelerated. Photons are emitted and absorbed by
those free electrons. Some of the photons escape
into space as coherent radiation.

One can learn a lot about EM waves by understanding
the nature of photons. For instance, standing waves
consist of photons that cannot stand still. The
illusion of a "standing" wave is just two waves of
photons moving in opposite directions at the speed
of light. Photons are not like mashed potatoes.
--
73, Cecil, IEEE, OOTC, http://www.w5dxp.com

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In article ,
Szczepan Bia³ek wrote:

Sometimes the screen on TV or cinema is perfectly white. This in cinema
reflect. This reflected light splitted with the prism has only three
frequences?

They're likely to be three bands of frequencies rather than three
narrow single-frequency lines, because the technologies used to create
the frequencies aren't narrow-band. But, yes, what you are seeing as
"perfectly white" under these circumstances is often *not* a smooth,
continuous spectrum.

In the case of a TV screen, you're seeing either:

- The mixed emissions of a set of red, green, and blue phosphors,
individually excited by electron beams [for CRT displays], or

- The emission from the phosphors of a cold-cathode fluorescent
backlighting lamp (a complex spectrum with multiple peaks) filtered
through red, green, and blue pixel-sized filters (for most LCD
tubes).

In traditional film cinema, you're seeing the emissions of an
incandescent or halogen bulb (fairly continuous spectrum) filtered
through three colors of dye in the film print.

The fact that these complex mixtures of overlapping color spectra can
look "pure white" to our eyes, is due in large part to our complex
nervous systems. Our eye/brain systems adapt to the mix of colors
present under differnet lighting conditions, and interpret different
combinations as "pure white" depending on what's available at the time.

This is why, for example, indoor fluorescent lighting can actually
look half-decent to our eyes once we get used to it (we "see" a fairly
complete range of colors there) but what looks "white" to use under
fluorescents will actually have a distinctly greenish cast to a film
or digital camera.

It's also why a rather curious phenomenon can be demonstrated. The
*exact* same mix of color emissions may look very different to us,
under different ambient lighting conditions... what might look
greenish outdoors will look pure white or even slightly pinkish under
indoor fluorescent lighting, because our brains *interpret* that input
differently due to the different surroundings.

--
Dave Platt AE6EO
Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!

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"Cecil Moore" wrote
...
Szczepan Bia³ek wrote:
Heck, only a few years ago they said a
particle could exist without mass.

It wrote Art.

Photons have zero *rest* mass. If they had mass at
rest, they could not travel at the speed of light.
The mass of a photon is due to its velocity, c in
free space. When a photon slows to less than the speed
of light in a medium, it gives up its energy to another
particle, e.g. an electron, and disappears.

3. Photons

EM radiation from amateur radio antennas is photonic.
RF energy is supplied to the antenna system by our
transmitters. Free electrons are accelerated and
decelerated. Photons are emitted and absorbed by
those free electrons. Some of the photons escape
into space as coherent radiation.

One can learn a lot about EM waves by understanding
the nature of photons. For instance, standing waves
consist of photons that cannot stand still. The
illusion of a "standing" wave is just two waves of
photons moving in opposite directions at the speed
of light. Photons are not like mashed potatoes.

Are photons like transverse wave or like longitudinal?
S*

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On Sat, 16 May 2009 20:11:34 +0200, Szczepan Bia?ek
wrote:

One can learn a lot about EM waves by understanding
the nature of photons. For instance, standing waves
consist of photons that cannot stand still. The
illusion of a "standing" wave is just two waves of
photons moving in opposite directions at the speed
of light. Photons are not like mashed potatoes.

Are photons like transverse wave or like longitudinal?

Do two trolls' imaginary contributions resonate at the interface?

73's
Richard Clark, KB7QHC

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"Dave Platt" wrote ...

In article ,
Szczepan Bia³ek wrote:

Sometimes the screen on TV or cinema is perfectly white. This in cinema
reflect. This reflected light splitted with the prism has only three
frequences?

They're likely to be three bands of frequencies rather than three
narrow single-frequency lines, because the technologies used to create
the frequencies aren't narrow-band. But, yes, what you are seeing as
"perfectly white" under these circumstances is often *not* a smooth,
continuous spectrum.

I was thinking that some transparent and semitransparent substances are
phosphorescent (some time in dark) but ALL are less or more fluorescent
(rework frequency). Rube in laser rewoork into one. But in laser are many
passes. But what happens in one pass?
May be that it rework also but only a little.

Raman discovered that some substances can rework one frequency into many
(also in higher).
May be that a cotton screan also rework.

In the case of a TV screen, you're seeing either:

- The mixed emissions of a set of red, green, and blue phosphors,
individually excited by electron beams [for CRT displays], or

- The emission from the phosphors of a cold-cathode fluorescent
backlighting lamp (a complex spectrum with multiple peaks) filtered
through red, green, and blue pixel-sized filters (for most LCD
tubes).

In traditional film cinema, you're seeing the emissions of an
incandescent or halogen bulb (fairly continuous spectrum) filtered
through three colors of dye in the film print.

The fact that these complex mixtures of overlapping color spectra can
look "pure white" to our eyes, is due in large part to our complex
nervous systems. Our eye/brain systems adapt to the mix of colors
present under differnet lighting conditions, and interpret different
combinations as "pure white" depending on what's available at the time.

Yes. But for me is interesting the phenomenon at reflecting, scatering and
refraction. May be that "polarisation" is an effect of that.

This is why, for example, indoor fluorescent lighting can actually
look half-decent to our eyes once we get used to it (we "see" a fairly
complete range of colors there) but what looks "white" to use under
fluorescents will actually have a distinctly greenish cast to a film
or digital camera.

It's also why a rather curious phenomenon can be demonstrated. The
*exact* same mix of color emissions may look very different to us,
under different ambient lighting conditions... what might look
greenish outdoors will look pure white or even slightly pinkish under
indoor fluorescent lighting, because our brains *interpret* that input
differently due to the different surroundings.

Is the light polarisation the hard prove that light vaves are transversal?
S*



--
Dave Platt AE6EO
Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!

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Szczepan Bia³ek wrote:
Are photons like transverse wave or like longitudinal?

The EM fields embodied by photons are transverse.
--
73, Cecil, IEEE, OOTC, http://www.w5dxp.com

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Cecil Moore wrote:

EM radiation from amateur radio antennas is photonic.

EM radiation from anything is both particles and waves.

For instance, standing waves
consist of photons that cannot stand still.

As opposed to consisting of photons that _can_ stand still? :-)

Interference is an example of the wavelike nature of light.

ac6xg

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"Szczepan Bialek" wrote in message
...
Raman discovered that some substances can rework one frequency into
many (also in higher).
May be that a cotton screan also rework.


This is a subject I have considerable experience in. My group at Eastman
developed a process Raman spectrometer that used communications grade
fibers to transmit both the excitation wavelength and the anti-Stokes
Raman scattered light. Chalcogenide fibers, at around $1K per foot,
would be needed to transmit the IR wavelengths needed for the analysis we
were doing. The communication grade fibers cost less than one foot of
the expensive fibers for the entire several hundred feet needed to
separate the analyzer from the chemical process. Our patents were
eventually licensed to the Rosemount division of Emerson Electric.

Raman spectroscopy is based on the _non-linear_ (inelastic) scattering of
photons. It is quite weak; more than 100 million photons are reflected
by the linear (elastic) Rayleigh scattering for every photon reflected by
Raman scattering.

I am convinced now that Szczepan Bialek is nothing more than an offensive
troll. It is best to ignore him as the physics newsgroups seem to have
done. May he bask in his own stupidity! Or perhaps he and Art and the
gays and the gay bashers could form their own "alt.troll" newsgroup.

--
73, Dr. Barry L. Ornitz WA4VZQ




--
73, Dr. Barry L. Ornitz WA4VZQ

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Jim Kelley wrote:
For instance, standing waves
consist of photons that cannot stand still.

As opposed to consisting of photons that _can_ stand still? :-)

Some people will argue that EM standing waves are
actually standing still which implies that photons
can stand still which they cannot. This is easy
to see if one visualizes standing waves of light
in free space as Hecht does in "Optics". There's
no voltage or current to muddy the issue. One is
forced to deal with photonic E-fields and H-fields
in free space.

It's the same old misconception. If net energy
transfer is zero, some believe that means the
energy carriers are not moving. But as Hecht
says, it is the *profile* of the standing wave
that doesn't move. The standing wave profile
is a human abstraction and according to Hecht,
standing waves do not deserve to be called waves
at all: "They might better not be called waves at
all, since they do not transport energy and momentum."
"Standing waves" is a misnomer, i.e. they don't stand
still and they do not meet the definition of "wave".

On another newsgroup, I pointed out the above
concept of EM waves just standing there is similar
to the idea that since the number of northbound
vehicles on the Golden Gate Bridge equal the number of
southbound vehicles, there is no net traffic flow and
therefore no maintenance of the bridge is required.
--
73, Cecil, IEEE, OOTC, http://www.w5dxp.com