| Topic: |
Science > Physics |
| User: |
"extremewanderer" |
| Date: |
07 Oct 2006 10:33:14 AM |
| Object: |
Collision of photons??? |
When we can see stars at night, it means that the photons [in the
visible spectrum] being emitted by the stars are able to reach our
eyes. During the day, the scattering of the sunlight does not let us
see the stars, does this mean that the photons coming from the stars
are unable to reach us because of the photons coming from the sun,
which are more numerous block them out. Or is it because, our eyes are
unable to see such a faint light during the day.
I have heard & read that on the moon, the stars will be visible during
the day, but in the moon landings the stars are not visible. The reason
given for this is that the glare of the sun is blocking out the stars.
Does this mean that the photons from the sun are actually colliding
with the photons coming from the stars?
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| User: "Sorcerer" |
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| Title: Re: Collision of photons??? |
07 Oct 2006 11:25:31 AM |
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"extremewanderer" <ewugkg@gmail.com> wrote in message
news:1160235194.259771.81720@h48g2000cwc.googlegroups.com...
| When we can see stars at night, it means that the photons [in the
| visible spectrum] being emitted by the stars are able to reach our
| eyes. During the day, the scattering of the sunlight does not let us
| see the stars, does this mean that the photons coming from the stars
| are unable to reach us because of the photons coming from the sun,
| which are more numerous block them out. Or is it because, our eyes are
| unable to see such a faint light during the day.
Your eyes are swamped. It is still possible to see stars in daylight from
the bottom of a deep well or mine shaft, I'm told, but I've never tried it.
|
| I have heard & read that on the moon, the stars will be visible during
| the day, but in the moon landings the stars are not visible. The reason
| given for this is that the glare of the sun is blocking out the stars.
| Does this mean that the photons from the sun are actually colliding
| with the photons coming from the stars?
Photons do not "collide" anymore than ripples on a pond
would collide. They pass through each other. The reason you
haven't seen stars in pictures from the moon is exactly the same
reason you do not see stars in ordinary photography on Earth,
they are not bright enough to show at ordinary shutter speeds.
http://tinyurl.com/gvb5w
See? No stars.
http://www.ius.edu/biology/fieldbiology/picfiles/pics/nightscene.jpg
I can see maybe one star in this one, but no detail of the moon,
which is far too bright. I could with the naked eye, though.
Street lights are far brighter than stars when it comes to photography.
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| User: "Jan Panteltje" |
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| Title: Re: Collision of photons??? |
07 Oct 2006 10:55:12 AM |
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On a sunny day (7 Oct 2006 08:33:14 -0700) it happened "extremewanderer"
<ewugkg@gmail.com> wrote in
<1160235194.259771.81720@h48g2000cwc.googlegroups.com>:
I have heard & read that on the moon, the stars will be visible during
the day, but in the moon landings the stars are not visible. The reason
given for this is that the glare of the sun is blocking out the stars.
Does this mean that the photons from the sun are actually colliding
with the photons coming from the stars?
There is no photon - photon collision, and the reason is simple:
A photon is a mathematical concept, and those do only collide in arguments.
There are plans for a photon-photon collision experiment to see if anything
comes out.
And there are also plans for a bigger gravity wave detector.
There are many plans, even for world peace.
In case of the moon, there are now coming digital cameras with much higher
dynamic range.
So first we have more and more pixels, so see finer detail.
But the luminance _range_ of a picture displayed on a normal PC is only 8 bits,
256 steps.
CCD sensors exist that have 16 bit depth, so 65536 steps, and in a picture
taken by such a sensor more low light objects should be visible in the moon case
(no atmosphere).
These CCD sensors are for example used to read the name on ships that do oil
spills at night (from an airplane).
You can, using special software, display a 256 steps part of the 65535 steps
luminance curve on a normal monitor.
El Pante
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| User: "BernardZ" |
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| Title: Re: Collision of photons??? |
07 Oct 2006 08:36:53 PM |
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In article <eg8il6$2ls$1@news.datemas.de>,
says...
There is no photon - photon collision, and the reason is simple:
A photon is a mathematical concept, and those do only collide in arguments.
There are plans for a photon-photon collision experiment to see if anything
comes out.
If there are plans for a photon-photon collision experiment to see if
anything comes out then there must be some arguments that it can occur.
--
The people that believe that the world is flat are proof that heaps of
time, huge amounts of scientific evidence, plenty of eyewitness
accounts, numerous experts opinion and mountains of photographs are not
enough to convince some people! What is particularly frustrating is
that there are many such people on the Usenet.
Observations of Bernard - No 104
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| User: "Raymond Yohros" |
|
| Title: Re: Collision of photons??? |
07 Oct 2006 10:53:31 PM |
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|
BernardZ wrote:
If there are plans for a photon-photon collision experiment to see if
anything comes out then there must be some arguments that it can occur.
particles with no mass dont collide with each other.
they simply get absorbed by matenergy.
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| User: "RP" |
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| Title: Re: Collision of photons??? |
07 Oct 2006 11:21:26 PM |
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Raymond Yohros wrote:
BernardZ wrote:
If there are plans for a photon-photon collision experiment to see if
anything comes out then there must be some arguments that it can occur.
particles with no mass dont collide with each other.
they simply get absorbed by matenergy.
Particles that don't exist can't collide with each other.
In the case of electron/positron pair production, the positronium atom
was already there. It has only one energy state, and as an atom it is
virutally undectable and virtually indestructable, being net neutral in
the far field, which begins at about 0.000000000000001 meters from its
barycenter. Only high frequency radiation, with wavelengths in the
vicinity of its diameter, can converge to split that atom apart. It is
probably one and the same as the neutrino.
I've calculated the orbital radius to be on the order of the classical
electron radius. I didn't use conventional elecromagnetic theory
however, which is one of the reasons that I don't have the particles
spiralling all the way in to anhillate each other. The minium radius
can be calculated directly by expanding the equation E=mc^2, where E is
the electromagnetic binding energy of the pair and m is one half the
total rest mass of the two particles.
kQQ'/d = mc^2
d = kQQ'/mc^2
m is the mass of the electron in kg and k is Coulomb's constant.
radius = d/2
Richard Perry
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| User: "FrediFizzx" |
|
| Title: Re: Collision of photons??? |
08 Oct 2006 12:36:49 AM |
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|
"RP" <no_mail_no_spam@yahoo.com> wrote in message
news:1160281286.605691.221390@e3g2000cwe.googlegroups.com...
Raymond Yohros wrote:
BernardZ wrote:
If there are plans for a photon-photon collision experiment to see
if
anything comes out then there must be some arguments that it can
occur.
particles with no mass dont collide with each other.
they simply get absorbed by matenergy.
Particles that don't exist can't collide with each other.
In the case of electron/positron pair production, the positronium atom
was already there. It has only one energy state, and as an atom it is
virutally undectable and virtually indestructable, being net neutral
in
the far field, which begins at about 0.000000000000001 meters from its
barycenter. Only high frequency radiation, with wavelengths in the
vicinity of its diameter, can converge to split that atom apart. It
is
probably one and the same as the neutrino.
Can't be. Spin is wrong for it to be a neutrino.
I've calculated the orbital radius to be on the order of the classical
electron radius. I didn't use conventional elecromagnetic theory
however, which is one of the reasons that I don't have the particles
spiralling all the way in to anhillate each other. The minium radius
can be calculated directly by expanding the equation E=mc^2, where E
is
the electromagnetic binding energy of the pair and m is one half the
total rest mass of the two particles.
kQQ'/d = mc^2
d = kQQ'/mc^2
m is the mass of the electron in kg and k is Coulomb's constant.
radius = d/2
Gooblygook. Look up positronium in a particle physics textbook. It has
been experimentally researched to death. ;-) You seem like such a smart
guy. Take the leap and study this stuff better.
Now for my whacko concept. ;-) "Positronium" is part of the fundamental
structure that supports EM radiation. But it "lives" all bound up in
another "spacetime", so to speak, intersecting with ours. When it
annihilates in our spacetime, it isn't really destroyed but just goes
back to where it "lives". Energy has to stay here. We are like living
on the event horizon of a extremely giant black hole. However, somehow
this "black hole" is special and we can't fall into it. Nor does it try
to suck us into it. So not really a black hole but don't really know
what else to call it. Well, actually it is partially trying to suck us
in. But can't because electrons, neutrons and protons are blocked from
entering. Unless they find a complementary "hole".
FrediFizzx
Quantum Vacuum Charge papers;
http://www.vacuum-physics.com/QVC/quantum_vacuum_charge.pdf
or postscript
http://www.vacuum-physics.com/QVC/quantum_vacuum_charge.ps
http://www.arxiv.org/abs/physics/0601110
http://www.vacuum-physics.com
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| User: "RP" |
|
| Title: Re: Collision of photons??? |
08 Oct 2006 09:56:19 AM |
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|
FrediFizzx wrote:
"RP" <no_mail_no_spam@yahoo.com> wrote in message
news:1160281286.605691.221390@e3g2000cwe.googlegroups.com...
Raymond Yohros wrote:
BernardZ wrote:
If there are plans for a photon-photon collision experiment to see
if
anything comes out then there must be some arguments that it can
occur.
particles with no mass dont collide with each other.
they simply get absorbed by matenergy.
Particles that don't exist can't collide with each other.
In the case of electron/positron pair production, the positronium atom
was already there. It has only one energy state, and as an atom it is
virutally undectable and virtually indestructable, being net neutral
in
the far field, which begins at about 0.000000000000001 meters from its
barycenter. Only high frequency radiation, with wavelengths in the
vicinity of its diameter, can converge to split that atom apart. It
is
probably one and the same as the neutrino.
Can't be. Spin is wrong for it to be a neutrino.
I've calculated the orbital radius to be on the order of the classical
electron radius. I didn't use conventional elecromagnetic theory
however, which is one of the reasons that I don't have the particles
spiralling all the way in to anhillate each other. The minium radius
can be calculated directly by expanding the equation E=mc^2, where E
is
the electromagnetic binding energy of the pair and m is one half the
total rest mass of the two particles.
kQQ'/d = mc^2
d = kQQ'/mc^2
m is the mass of the electron in kg and k is Coulomb's constant.
radius = d/2
Gooblygook. Look up positronium in a particle physics textbook. It has
been experimentally researched to death. ;-) You seem like such a smart
guy. Take the leap and study this stuff better.
Now for my whacko concept. ;-) "Positronium" is part of the fundamental
structure that supports EM radiation. But it "lives" all bound up in
another "spacetime", so to speak, intersecting with ours. When it
annihilates in our spacetime, it isn't really destroyed but just goes
back to where it "lives". Energy has to stay here. We are like living
on the event horizon of a extremely giant black hole. However, somehow
this "black hole" is special and we can't fall into it. Nor does it try
to suck us into it. So not really a black hole but don't really know
what else to call it. Well, actually it is partially trying to suck us
in. But can't because electrons, neutrons and protons are blocked from
entering. Unless they find a complementary "hole".
FrediFizzx
Different brand of Gooblygook? :)
Very many things have been researched to death, but it doesn't
necessarily follow that correct conclusions have been drawn. When you
get into the seriously abstract notions involved in particle phsyics,
you should keep in mind that assumptions increase the likelyhood of
incorrectness logarithmically as more assumptions are piled upon each
other. I know just enough about particle physics to see that it's based
entirely upon wild assed conjecture. The epicyclic expansion is
accelerating logarithmically too, which is the only thing keeping the
venture profitable. More funding for development of newer and better
epicycles.
What's your definition of spin?
Richard Perry
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| User: "RP" |
|
| Title: Re: Collision of photons??? |
08 Oct 2006 09:47:30 AM |
|
|
FrediFizzx wrote:
"RP" <no_mail_no_spam@yahoo.com> wrote in message
news:1160281286.605691.221390@e3g2000cwe.googlegroups.com...
Raymond Yohros wrote:
BernardZ wrote:
If there are plans for a photon-photon collision experiment to see
if
anything comes out then there must be some arguments that it can
occur.
particles with no mass dont collide with each other.
they simply get absorbed by matenergy.
Particles that don't exist can't collide with each other.
In the case of electron/positron pair production, the positronium atom
was already there. It has only one energy state, and as an atom it is
virutally undectable and virtually indestructable, being net neutral
in
the far field, which begins at about 0.000000000000001 meters from its
barycenter. Only high frequency radiation, with wavelengths in the
vicinity of its diameter, can converge to split that atom apart. It
is
probably one and the same as the neutrino.
Can't be. Spin is wrong for it to be a neutrino.
I've calculated the orbital radius to be on the order of the classical
electron radius. I didn't use conventional elecromagnetic theory
however, which is one of the reasons that I don't have the particles
spiralling all the way in to anhillate each other. The minium radius
can be calculated directly by expanding the equation E=mc^2, where E
is
the electromagnetic binding energy of the pair and m is one half the
total rest mass of the two particles.
kQQ'/d = mc^2
d = kQQ'/mc^2
m is the mass of the electron in kg and k is Coulomb's constant.
radius = d/2
Gooblygook. Look up positronium in a particle physics textbook. It has
been experimentally researched to death. ;-) You seem like such a smart
guy. Take the leap and study this stuff better.
Now for my whacko concept. ;-) "Positronium" is part of the fundamental
structure that supports EM radiation. But it "lives" all bound up in
another "spacetime", so to speak, intersecting with ours. When it
annihilates in our spacetime, it isn't really destroyed but just goes
back to where it "lives". Energy has to stay here. We are like living
on the event horizon of a extremely giant black hole. However, somehow
this "black hole" is special and we can't fall into it. Nor does it try
to suck us into it. So not really a black hole but don't really know
what else to call it. Well, actually it is partially trying to suck us
in. But can't because electrons, neutrons and protons are blocked from
entering. Unless they find a complementary "hole".
Different brand of Gooblygook? :)
Very many things have been researched to death, but it doesn't
necessarily follow that correct conclusions have been drawn. When you
get into the seriously abstract notions involved in particle phsyics,
you should keep in mind that assumptions increase the likelyhood of
incorrectness algorithmically as more assumptions are piled upon each
other. I know just enough about particle physics to see that it's based
entirely upon wild assed conjecture. The epicyclic expansion is
accellerating logarithmically too, which is the only thing keeping the
venture profitable. More funding for developement of newer and better
epicycles.
What's your definition of spin?
.
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| User: "Jan Panteltje" |
|
| Title: Re: Collision of photons??? |
08 Oct 2006 05:30:22 AM |
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|
On a sunny day (Sun, 8 Oct 2006 11:36:53 +1000) it happened BernardZ
<bernardZ@Nospam.com> wrote in <MPG.1f93013e71a9f058989bce@news>:
In article <eg8il6$2ls$1@news.datemas.de>,
says...
There is no photon - photon collision, and the reason is simple:
A photon is a mathematical concept, and those do only collide in arguments.
There are plans for a photon-photon collision experiment to see if anything
comes out.
If there are plans for a photon-photon collision experiment to see if
anything comes out then there must be some arguments that it can occur.
Well, here is a link that explains some more, and links to current experiments.
http://www.answers.com/topic/two-photon-physics
The problem I have with this is, that at these _very high_ energy levels, and
with space not being empty, and likely non linear, you _could_ see something.
And from a wave perspective at high energy levels in a non linear
medium 'mixing' (multiplication) so other 'color' photons _could_ occur.
So 'how empty is the space they try it in' is perhaps an issue.
As a physics amateur I would say if you use enough energy _always_ something
will happen.
;-)
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| User: "" |
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| Title: Re: Collision of photons??? |
07 Oct 2006 11:05:02 AM |
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extremewanderer <ewugkg@gmail.com> wrote:
When we can see stars at night, it means that the photons [in the
visible spectrum] being emitted by the stars are able to reach our
eyes. During the day, the scattering of the sunlight does not let us
see the stars, does this mean that the photons coming from the stars
are unable to reach us because of the photons coming from the sun,
which are more numerous block them out. Or is it because, our eyes are
unable to see such a faint light during the day.
I have heard & read that on the moon, the stars will be visible during
the day, but in the moon landings the stars are not visible. The reason
given for this is that the glare of the sun is blocking out the stars.
Does this mean that the photons from the sun are actually colliding
with the photons coming from the stars?
It means that optical detectors (eyes, cameras) have finite dynamic
range and bright things swamp out dim things.
How bright do car headlights appear in the middle of the night compared
to during the day?
--
Jim Pennino
Remove .spam.sux to reply.
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| User: "srp" |
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| Title: Re: Collision of photons??? |
08 Oct 2006 10:14:38 AM |
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extremewanderer a écrit :
When we can see stars at night, it means that the photons [in the
visible spectrum] being emitted by the stars are able to reach our
eyes. During the day, the scattering of the sunlight does not let us
see the stars, does this mean that the photons coming from the stars
are unable to reach us because of the photons coming from the sun,
which are more numerous block them out. Or is it because, our eyes are
unable to see such a faint light during the day.
I have heard & read that on the moon, the stars will be visible during
the day, but in the moon landings the stars are not visible. The reason
given for this is that the glare of the sun is blocking out the stars.
Does this mean that the photons from the sun are actually colliding
with the photons coming from the stars?
It only means that light from the stars is so weak with respect to that
coming from the much closer Sun that it is lost in the more intense
background.
You have a nice example of such a case with the space shuttle taking
off. On close ups of lift offs you can hardly make out the flames
coming from the shuttle boosters, so much so that if you don't pay
attention you may think they are not on, despite the fact that they
are operating full blast, because the light coming from them is
insignificant compared to the many orders of magnitude more intense
glare of the main boosters.
Photons do interact however. This was experimentally demonstrated
as recently as 1997 by a team led by Kirk McDonald, at the Stanford
Linear Accelerator (SLAC) that it is possible to produce
electron/positron pairs by converging towards a single point in
space sufficiently concentrated streams of sufficiently energetic
photons, one of the stream having to be made up of photons of
energy 1.022 MeV or more.
If you look up SLAC archives, you should be able to trace info
on that experiment.
André Michaud
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| User: "Sam Wormley" |
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| Title: Re: Collision of photons??? |
07 Oct 2006 11:31:37 AM |
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extremewanderer wrote:
When we can see stars at night, it means that the photons [in the
visible spectrum] being emitted by the stars are able to reach our
eyes. During the day, the scattering of the sunlight does not let us
see the stars, does this mean that the photons coming from the stars
are unable to reach us because of the photons coming from the sun,
No
which are more numerous block them out. Or is it because, our eyes are
unable to see such a faint light during the day.
Our eye receive the stellar photons, but are flooded with others.
Related URLs:
http://www.jesus.cam.ac.uk/college/flamsteed.htm
http://www.weatherman.com/wxastro6.htm
"Exactly what magnitude stars can be seen by day? Apparently the limit
runs from 1st to 4th magnitude, depending on the brightness of the sky.
The closer to sunrise, and sunset, the dimmer the stars that can be
detected. Indeed, several minutes before sunset [last fall, you could]
see many of Jupiter's moons through your scope! Can you see a shadow
crossing as well? I haven't tried it, but I bet you could!"
http://www.google.com/search?q=observing+stars+daytime
I have heard & read that on the moon, the stars will be visible during
the day, but in the moon landings the stars are not visible. The reason
given for this is that the glare of the sun is blocking out the stars.
Does this mean that the photons from the sun are actually colliding
with the photons coming from the stars?
The film simply didn't have the dynamic range to record both the
sunlit surface and the faint stars simultaneously.
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