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Sue...
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 Posted: Thu Jul 10, 2008 6:09 pm Post subject: Re: massless or massive photon? |
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On Jul 10, 1:51 pm, "Juan R." González-Álvarez
<juanREM...@canonicalscience.com> wrote:
| Quote: |
Sue... wrote on Thu, 10 Jul 2008 09:17:08 -0700:
On Jul 10, 11:55 am, "Juan R." González-Álvarez
juanREM...@canonicalscience.com> wrote:
Sue... wrote on Thu, 10 Jul 2008 08:18:23 -0700:
On Jul 10, 10:59 am, "Juan R." González-Álvarez
juanREM...@canonicalscience.com> wrote:
Sue... wrote on Thu, 10 Jul 2008 07:30:44 -0700:
So you then have an imaginary mass that won't couple to a real
gravito-inertial field.
And your proof that m is imaginary for H = pc is?
In sci.physics.foundations Charles said that mass would be zero
for (2), but neither he offered any proof.
When an atom emits light quanta it loose mass.
When an atom absorbs light quanta it gains mass.
But the quanta absorbed is seldom 100 percent causaly related to
the emission. You have to consider all the other EM disturbances
that could contribute to absorbtion and subtract them out. Longer
paths involve more participants to be subtracted so the mass
approaches zero quicly. Zero is close enough for me.  )
In the subatomic realm the certainty
of a causal link is much higher and
surely worth accounting for.
http://en.wikipedia.org/wiki/Feynman_diagram#Motivation_and_history
Sue...
No proof presented.
You will be my proof when you spend 10 years avoiding
electromagnetism when you could learn it in three.
[...]
But you continue without presenting any proof...
Some authors are developing electrodynamic theories where the photon
has a small mass and still the theory is compatible with high-precision
tests of QED:
E.V. Stefanovich,
Quantum Field Theory without Infinities Ann. Phys. 292 (2001),
139-156.
I explained earlier how that can work. Disroving a theory is the
author's burden, certainly not mine.
"Cargo Cult Science"
http://wwwcdf.pd.infn.it/~loreti/science.html
See also discussion on massive photons on "S9c. What about relativistic
QFT at finite times?" on
http://www.mat.univie.ac.at/~neum/physics-faq.txt
There is an excellent discussion of the issue of experimental bounds on
massive photons in
http://arxiv.org/abs/hep-ph/0306245
Therefore your links, whereas interesting, are not addressing the issue
of this thread: Is (2), in my original post, representing same particle
than (1) or some other massive particle?
It seldom qualifies as a particle at all.
http://nobelprize.org/physics/articles/ekspong/index.html...So anybody
that cares what its mass is has already defined it by the interaction it
participates in.
??
Perhaps the refugees from EM-101 need to know?
http://farside.ph.utexas.edu/teaching/em/lectures/lectures.html
http://web.mit.edu/8.02t/www/802TEAL3D/visualizations/light/index.htm
http://www.ee.surrey.ac.uk/Personal/D.Jefferies/antennas.html
Sue...
Well, I already remarked that theories with massive photon are giving the
same experimental answers that classical electrodynamics in the
corresponding limit.
And also pointed to one example of quantum theory with massive photon
gives the same scattering amplitudes that computed using Feynman diagrams
for QED
|
If you have a keen eye you may notice that only
three of the four forces on this web page has
a summary explanation.
http://hyperphysics.phy-astr.gsu.edu/hbase/forces/funfor.html
*Mass* is very relevant to what is absent from the page.
Can you write the missing material in terms of
your massive photon?
Sue...
| Quote: |
Your links continue to be interesting but of no help. You continue
avoiding to reply a simple question I did.
--
Center for CANONICAL |SCIENCE) http://canonicalscience.org |
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Sue...
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Eric Gisse
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| Posted: Thu Jul 10, 2008 9:20 pm Post subject: Re: massless or massive photon? |
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On Jul 10, 10:58 am, "Pmb" <physics_wo...@yahoo.com> wrote:
| Quote: |
"Juan R. González-Álvarez" <juanREM...@canonicalscience.com> wrote in
messagenews:pan.2008.07.10.17.56.09@canonicalscience.com...
Dono wrote on Thu, 10 Jul 2008 09:52:26 -0700:
No one confused the hamiltonian with the lagrangian (not even you,
(...)
Eric confounded both, wrote H = L in previous message and did incorrect
claims about a blog article. You also did :-)
Eric isn't a physicist so don't expect him to be precise as one.
|
Yea but I'm smarter than both of you. By such a wide margin it boggles
the mind.
Exactly _neither of you_ are physicists which makes the snipe that
much more lolful. No, pete - sending complaints to a graduate school
doesn't count. No, Juan - lying about going to a conference doesn't
count.
Hell, you guys aren't even very good scientists. In fact, neither of
you are really that good of persons now that I think about it. Pete
has his whining bitchfits, and Juan has his compulsive intellectual
dishonesty.
I was going to make a point before I remembered how much I don't like
the two of you. Oh yea - the Lagrangian and Hamiltonian are equal when
there are no potentials under consideration. I figured between the two
of you quotemining classical mechanics textbooks, one of you would
have figured that out.
| Quote: |
The Hamiltonian is identical to Jacobi's integral (sometimes called the
"energy function") in value. The former is expressed in terms of position
and canonical momentum whereas the later is expressed in terms of position
(q) and its first time derivative (dq/dt)
Pete
|
Congratulations Pete - you opened a classical mechanics textbook at
some point in your life. Skip to the chapter that discusses the
Hamiltonian and how it relates to the Lagrangian.
That way you won't freak the fuck out when I use a trivial fact that's
obviously true but not explicitly written in your textbooks. |
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Eric Gisse
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| Posted: Thu Jul 10, 2008 9:27 pm Post subject: Re: massless or massive photon? |
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On Jul 10, 9:54 am, "Juan R." González-Álvarez
<juanREM...@canonicalscience.com> wrote:
| Quote: |
Dono wrote on Thu, 10 Jul 2008 09:52:26 -0700:
No one confused the hamiltonian with the lagrangian (not even you,
(...)
Eric confounded both, wrote H = L in previous message and did incorrect
claims about a blog article. You also did 
|
Oh I'm sorry, are the big words and complicated symbols confusing you?
Here - Eric will help you past those little stumbling blocks that make
science so difficult.
The Lagrangian for a classical system is defined to be T - V.
Are you following me? Good.
The Hamiltonian for a classical system is defined to be T + V.
Now take a minute to relax, because this is where the magic happens
and you don't want to miss it!
When V = 0 ... H and L are the same. Isn't that fuckin' amazing?
And where did I get the value for L? Well - it was right there on your
blog. Sure I could have referenced Goldstein, Symon, Jackson, Misner /
Thorne / Wheeler, Carroll, or even Wiki-fucking-pedia.
However those references just lacked the certain something extra I get
by shoving your micro thought back in your face.
Alert readers: Given Juan's recent history of deleting posts on google
groups, who wants to take a guess how long his micro thought [sooo
apt] will stay up for the world to see?
| Quote: |
--
Center for CANONICAL |SCIENCE) http://canonicalscience.org |
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Eric Gisse
Guest
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| Posted: Thu Jul 10, 2008 10:33 pm Post subject: Re: massless or massive photon? |
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On Jul 10, 2:14 pm, "Pmb" <physics_wo...@yahoo.com> wrote:
| Quote: |
"Eric Gisse" <jowr...@gmail.com> wrote in message
news:41d28527-f39e-4ea6-9977-fcfa73c66f1b@e53g2000hsa.googlegroups.com...
On Jul 10, 9:54 am, "Juan R." González-Álvarez
juanREM...@canonicalscience.com> wrote:
Dono wrote on Thu, 10 Jul 2008 09:52:26 -0700:
No one confused the hamiltonian with the lagrangian (not even you,
(...)
Eric confounded both, wrote H = L in previous message and did incorrect
claims about a blog article. You also did \
Okay. Enough is enough. You've provided more than adequate reason to be
killfiled. Plonk!
|
....and here Pete realizes I'm right. Whoops! |
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Pmb
Guest
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| Posted: Thu Jul 10, 2008 11:54 pm Post subject: Re: massless or massive photon? |
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|
"Juan R. González-Álvarez" <juanREMOVE@canonicalscience.com> wrote in
message news:pan.2008.07.10.17.53.02@canonicalscience.com...
| Quote: |
Sue... wrote on Thu, 10 Jul 2008 09:17:08 -0700:
On Jul 10, 11:55 am, "Juan R." González-Álvarez
juanREM...@canonicalscience.com> wrote:
Sue... wrote on Thu, 10 Jul 2008 08:18:23 -0700:
On Jul 10, 10:59 am, "Juan R." González-Álvarez
juanREM...@canonicalscience.com> wrote:
Sue... wrote on Thu, 10 Jul 2008 07:30:44 -0700:
So you then have an imaginary mass that won't couple to a real
gravito-inertial field.
And your proof that m is imaginary for H = pc is?
In sci.physics.foundations Charles said that mass would be zero
for (2), but neither he offered any proof.
When an atom emits light quanta it loose mass.
When an atom absorbs light quanta it gains mass.
But the quanta absorbed is seldom 100 percent causaly related to
the emission. You have to consider all the other EM disturbances
that could contribute to absorbtion and subtract them out. Longer
paths involve more participants to be subtracted so the mass
approaches zero quicly. Zero is close enough for me. )
In the subatomic realm the certainty
of a causal link is much higher and
surely worth accounting for.
http://en.wikipedia.org/wiki/Feynman_diagram#Motivation_and_history
Sue...
No proof presented.
You will be my proof when you spend 10 years avoiding
electromagnetism when you could learn it in three.
[...]
But you continue without presenting any proof...
Some authors are developing electrodynamic theories where the photon
has a small mass and still the theory is compatible with high-precision
tests of QED:
E.V. Stefanovich,
Quantum Field Theory without Infinities Ann. Phys. 292 (2001),
139-156.
I explained earlier how that can work. Disroving a theory is the
author's burden, certainly not mine.
"Cargo Cult Science"
http://wwwcdf.pd.infn.it/~loreti/science.html
See also discussion on massive photons on "S9c. What about relativistic
QFT at finite times?" on
http://www.mat.univie.ac.at/~neum/physics-faq.txt
There is an excellent discussion of the issue of experimental bounds on
massive photons in
http://arxiv.org/abs/hep-ph/0306245
Therefore your links, whereas interesting, are not addressing the issue
of this thread: Is (2), in my original post, representing same particle
than (1) or some other massive particle?
It seldom qualifies as a particle at all.
http://nobelprize.org/physics/articles/ekspong/index.html ...So anybody
that cares what its mass is has already defined it by the interaction it
participates in.
??
Perhaps the refugees from EM-101 need to know?
http://farside.ph.utexas.edu/teaching/em/lectures/lectures.html
http://web.mit.edu/8.02t/www/802TEAL3D/visualizations/light/index.htm
http://www.ee.surrey.ac.uk/Personal/D.Jefferies/antennas.html
Sue...
Well, I already remarked that theories with massive photon are giving the
same experimental answers that classical electrodynamics in the
corresponding limit.
And also pointed to one example of quantum theory with massive photon
gives the same scattering amplitudes that computed using Feynman diagrams
for QED
Your links continue to be interesting but of no help. You continue
avoiding to reply a simple question I did.
|
It would be helpful if people would define their terms here. I.e. what
definition of "mass" is being used here? Proper mass or inertial mass?
Pete |
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Pmb
Guest
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| Posted: Thu Jul 10, 2008 11:58 pm Post subject: Re: massless or massive photon? |
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|
"Juan R. González-Álvarez" <juanREMOVE@canonicalscience.com> wrote in
message news:pan.2008.07.10.17.56.09@canonicalscience.com...
| Quote: |
Dono wrote on Thu, 10 Jul 2008 09:52:26 -0700:
No one confused the hamiltonian with the lagrangian (not even you,
(...)
Eric confounded both, wrote H = L in previous message and did incorrect
claims about a blog article. You also did
|
Eric isn't a physicist so don't expect him to be precise as one.
The Hamiltonian is identical to Jacobi's integral (sometimes called the
"energy function") in value. The former is expressed in terms of position
and canonical momentum whereas the later is expressed in terms of position
(q) and its first time derivative (dq/dt)
Pete |
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Pmb
Guest
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| Posted: Fri Jul 11, 2008 12:49 am Post subject: Re: massless or massive photon? |
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|
"Sue..." <suzysewnshow@yahoo.com.au> wrote in message
news:c46db903-ef7d-42a8-b91a-3f17fc54f884@d45g2000hsc.googlegroups.com...
Thanks for clarifying. Now, is that what Juan is referring to?
Pete |
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Guest
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| Posted: Fri Jul 11, 2008 2:07 am Post subject: Re: massless or massive photon? |
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On Jul 9, 8:03 pm, "Sue..." <suzysewns...@yahoo.com.au> wrote:
xxein: Sorry to have made myself appear stupid to you. I am
lightyears beyond such twins.
It's just that it appears that everybody has an answer for everything
and none of them coincide wrt to the other.
It may be that nothing really has a mass. What does a lump of
entangled energy feel like? Can it have a velocity (even if only
relative)? Can it have a momentum-like effect?
Although individual photons are measured to have a velocity of c in
all FORs, it does not necessarily follow that a one-way speed of c is
present in that frame. You don't measure the same in a different FOR,
do you? The point here is that in order to measure a photon's
velocity the same in different FORs, you would have to either contain
all photons in your FOR (and the hell with anyone else's), or that we
measure only TWLS and not OWLS. The matter of consideration is
obvious.
It's like tuning an engine. There is a dependency on timing, advance,
fuel flow and let's not forget how an engine is constructed to work.
But there's a difference between an engine and a physic. One is
physics and the forgotten step-child is the underlying physic.
It is not possible to make an engine without the underlying physic.
Many of our theories tend to side-step this basic issue and just make
some kind of continuity that is not deserved in in the physic's
(itself) breath. Yeah. It happens. We interfere. We can do that on
a small extent. But that extent is chosen by us. We can make
anything we want to out of it for how we think.
We can make a measurement, but we cannot know if we have captured the
physic by any such measurement. Certainly a physics is a local
phenomena (ex: Relativity) but it has to have a physic to rule how it
can work. It seems that no one makes this distinction.
This is what I mean by separating subjective measurability into a
different class to that of an objective viewpoint. Nobody seems to
understand.
As long as we can make an engine, who cares? That is the state of our
science anymore.
In a way, I hope that our minds could be obliterated so that we are
forced into re-thinking. |
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Sue...
Guest
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| Posted: Fri Jul 11, 2008 2:51 am Post subject: Re: massless or massive photon? |
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On Jul 10, 10:07 pm, xxe...@gmail.com wrote:
| Quote: |
On Jul 9, 8:03 pm, "Sue..." <suzysewns...@yahoo.com.au> wrote:
On Jul 9, 7:38 pm, xxe...@gmail.com wrote:
[...]
Come to think about, I want all the criticism and abuse for my
thinking about this. I want to learn like I suppose everyone else
does.
Well...
Try using a wave model for light. When the anomalous twin
vanishes you may have learned *better* that everyone else.
http://farside.ph.utexas.edu/teaching/em/lectures/lectures.html
Sue...
xxein: Sorry to have made myself appear stupid to you. I am
lightyears beyond such twins.
It's just that it appears that everybody has an answer for everything
and none of them coincide wrt to the other.
It may be that nothing really has a mass. What does a lump of
entangled energy feel like? Can it have a velocity (even if only
relative)? Can it have a momentum-like effect?
|
Yes... I often wonder if electrons should "fall".
Until my local welding supply begins selling them
in containers that I can put on a scale I am
remaining skeptical... but also not loosing
much sleep over it.
| Quote: |
Although individual photons are measured to have a velocity of c in
all FORs, it does not necessarily follow that a one-way speed of c is
present in that frame. You don't measure the same in a different FOR,
do you? The point here is that in order to measure a photon's
velocity the same in different FORs, you would have to either contain
all photons in your FOR (and the hell with anyone else's), or that we
measure only TWLS and not OWLS. The matter of consideration is
obvious.
|
Q. What makes a bullet move in a straight line.
A. It seldom does. Its mass is coupled to neighboring masses.
Q. What makes light move in a straight line?
A. Antenna gain and homogenous or favourable dielectric.
http://www.rp-photonics.com/gaussian_beams.html
| Quote: |
It's like tuning an engine. There is a dependency on timing, advance,
fuel flow and let's not forget how an engine is constructed to work.
But there's a difference between an engine and a physic. One is
physics and the forgotten step-child is the underlying physic.
It is not possible to make an engine without the underlying physic.
Many of our theories tend to side-step this basic issue and just make
some kind of continuity that is not deserved in in the physic's
(itself) breath. Yeah. It happens. We interfere. We can do that on
a small extent. But that extent is chosen by us. We can make
anything we want to out of it for how we think.
|
For the particle we have never met, discription
frequently preceeds discovery.
<<I think equation guessing might be the best method to
proceed to obtain the laws for the part of physics which
is presently unknown. Yet, when I was much younger, I
tried this equation guessing and I have seen many students
try this, but it is very easy to go off in wildly incorrect
and impossible directions. I think the problem is not to
find the best or most efficient method to proceed to a
discovery, but to find any method at all. Physical
reasoning does help some people to generate suggestions
as to how the unknown may be related to the known.>>
--R.P.Feynman
http://nobelprize.org/nobel_prizes/physics/laureates/1965/feynman-lecture.html
| Quote: |
We can make a measurement, but we cannot know if we have captured the
physic by any such measurement. Certainly a physics is a local
phenomena (ex: Relativity) but it has to have a physic to rule how it
can work. It seems that no one makes this distinction.
|
Are you a sailor? Only sailors have a god given right
to complain. )
The *mechanism* is certainly more interesting and informs
further advances but the *formalism* is what we must test.
Without that, it is not science.
| Quote: |
This is what I mean by separating subjective measurability into a
different class to that of an objective viewpoint. Nobody seems to
understand.
|
You are describing light in terms of Newton's laws.
Try describing Newton's laws in terms of light.
"Relativity and electromagnetism"
http://farside.ph.utexas.edu/teaching/em/lectures/node106.html
"The Origin of Gravity" [untestable mechanism ]
http://arxiv.org/abs/physics/0107015v6
| Quote: |
As long as we can make an engine, who cares? That is the state of our
science anymore.
In a way, I hope that our minds could be obliterated so that we are
forced into re-thinking.
|
Ouch! )
Sue... |
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Pmb
Guest
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| Posted: Fri Jul 11, 2008 3:13 am Post subject: Re: massless or massive photon? |
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|
"Eric Gisse" <jowr.pi@gmail.com> wrote in message
news:0ec8ec5c-79aa-4cc8-aa04-fe1644bc3733@j22g2000hsf.googlegroups.com...
On Jul 10, 10:58 am, "Pmb" <physics_wo...@yahoo.com> wrote:
| Quote: |
"Juan R. González-Álvarez" <juanREM...@canonicalscience.com> wrote in
messagenews:pan.2008.07.10.17.56.09@canonicalscience.com...
Dono wrote on Thu, 10 Jul 2008 09:52:26 -0700:
No one confused the hamiltonian with the lagrangian (not even you,
(...)
Eric confounded both, wrote H = L in previous message and did incorrect
claims about a blog article. You also did :-)
Eric isn't a physicist so don't expect him to be precise as one.
Yea but I'm smarter than both of you.
|
Yah! Right! LOL!! You sure haven't demonstrated that here in the many
years I've been posting.
| Quote: |
Exactly _neither of you_ are physicists which makes the snipe that
much more lolful.
|
Well that just goes to show how little you know. I have a BA in physics and
did some graduate work at Northeastern University
| Quote: |
No, pete - sending complaints to a graduate school
doesn't count.
|
You're one very silly boy Eric. LOL!!
| Quote: |
Hell, you guys aren't even very good scientists. In fact, neither of
you are really that good of persons now that I think about it. Pete
has his whining bitchfits, ..
|
Yah. Right! Actually you've just proven to us that its you who is more
likely to have a bitchfit.
| Quote: |
and Juan has his compulsive intellectual dishonesty.
|
According to you? Sorry Eric but you're not the sort of person I'd take
their word for.
| Quote: |
:I was going to make a point before I remembered how much I don't like
the two of you.
|
That's another strike against you. You're making personal judgements on
people you've never met based on superficial impressions on what you read on
a newsgroup. You have demonstrated that you read into things which were
never there.
| Quote: |
Oh yea - the Lagrangian and Hamiltonian are equal when
there are no potentials under consideration. I figured between the two
of you quotemining classical mechanics textbooks, one of you would
have figured that out.
|
Oh my! Now you've shown that you don't know the basics of analytical
mechanics!! LOL!!
| Quote: |
The Hamiltonian is identical to Jacobi's integral (sometimes called the
"energy function") in value. The former is expressed in terms of position
and canonical momentum whereas the later is expressed in terms of
position
(q) and its first time derivative (dq/dt)
Pete
Congratulations Pete - you opened a classical mechanics textbook at
some point in your life.
|
Its called a "college education".
| Quote: |
Skip to the chapter that discusses the
Hamiltonian and how it relates to the Lagrangian.
|
Oy! Eric you aer such a silly boy! Who in the world are you attempting to
impress? It sure isn't I.
| Quote: |
That way you won't freak the fuck out when I use a trivial fact that's
obviously true but not explicitly written in your textbooks.
|
You've just proven that you don't know even the most simplest parts of
analytical mechanics by the claim you made above regarding potentials.
Sorry Eric but all you've done here is to demonstrate what an arrogant sob
you are.
Later
Pete |
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Pmb
Guest
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| Posted: Fri Jul 11, 2008 3:14 am Post subject: Re: massless or massive photon? |
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"Eric Gisse" <jowr.pi@gmail.com> wrote in message
news:41d28527-f39e-4ea6-9977-fcfa73c66f1b@e53g2000hsa.googlegroups.com...
On Jul 10, 9:54 am, "Juan R." González-Álvarez
<juanREM...@canonicalscience.com> wrote:
| Quote: |
Dono wrote on Thu, 10 Jul 2008 09:52:26 -0700:
No one confused the hamiltonian with the lagrangian (not even you,
(...)
Eric confounded both, wrote H = L in previous message and did incorrect
claims about a blog article. You also did \
|
Okay. Enough is enough. You've provided more than adequate reason to be
killfiled. Plonk! |
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Pmb
Guest
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| Posted: Fri Jul 11, 2008 3:59 am Post subject: Re: massless or massive photon? |
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"Pmb" <physics_world@yahoo.com> wrote in message
news:IP6dnTwT9KFyFOvVnZ2dnUVZ_qHinZ2d@comcast.com...
| Quote: |
"Eric Gisse" <jowr.pi@gmail.com> wrote in message
news:41d28527-f39e-4ea6-9977-fcfa73c66f1b@e53g2000hsa.googlegroups.com...
On Jul 10, 9:54 am, "Juan R." González-Álvarez
juanREM...@canonicalscience.com> wrote:
Dono wrote on Thu, 10 Jul 2008 09:52:26 -0700:
No one confused the hamiltonian with the lagrangian (not even you,
(...)
Eric confounded both, wrote H = L in previous message and did incorrect
claims about a blog article. You also did \
Okay. Enough is enough. You've provided more than adequate reason to be
killfiled. Plonk!
|
btw - that was directed towards Eric |
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Tom Roberts
Guest
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| Posted: Fri Jul 11, 2008 6:54 am Post subject: Re: massless or massive photon? |
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Juan R. GonzĂĄlez-Ălvarez wrote:
| Quote: |
The usual argument for massless photons uses the Hamiltonian [...]
H = pc
|
You notion of "usual" and mine differ ENORMOUSLY.
First, I cannot see how such a Lagrangian gives photons at all -- for
that one needs a QUANTUM Lagrangian, as photons are inherently quantum
objects. If your theory does not have any photons, how can you sensibly
ask questions about their mass?
Second, given a proper quantum Lagrangian (and the corresponding
Hamiltonian if you wish), there's no general theoretical argument that
requires photons to be massless.
The REAL argument for massless photons is that when one treats the mass
of the photon as a free parameter and fits the theory to experimental
observations, one finds that the mass must be an INCREDIBLY small value,
and is consistent with zero. The PDG lists the current upper bound on
the photon mass as 6*10^-17 eV/c^2.
To put that in perspective, the lightest other particle
known (except neutrinos whose masses are not known) is the
electron. If an electron were scaled up to have the mass
of the earth, then the upper bound on the photon mass would
be scaled up to the mass of a half cubic meter of water.
| Quote: |
If alternatively we start assuming (v = c) in the transformation, the
result is
H = pc - L = pc (2)
where no assumption was taken about the mass.
Is this Hamiltonian (2) representing some kind of massive photon (somewhat
as in Proca theory [#]) or is really the same that (1)?
|
The same objections apply. But on the question of this being different
from (1), ask yourself: what changes in the meanings of symbols have
occurred? If none, then these are obviously the same. But that is a
subtle question, in particular: what is the meaning of "c"?
| Quote: |
Well, I already remarked that theories with massive photon are giving the
same experimental answers that classical electrodynamics in the
corresponding limit.
And also pointed to one example of quantum theory with massive photon
gives the same scattering amplitudes that computed using Feynman diagrams
for QED
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But that it not how one tests theories! To do that, one goes to the PDG
website, looks up the experiments that they used to establish their
limit on the photon mass, and one fits the theory with a massive photon
to the experimental data, leaving mass as a free parameter in the
theory. But, of course, that is essentially what those experimenters and
the PDG already did to obtain their limit.
Tom Roberts |
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Juan R." González-Álvarez
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| Posted: Fri Jul 11, 2008 8:57 am Post subject: Re: massless or massive photon? |
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Pmb wrote on Thu, 10 Jul 2008 14:54:01 -0400:
| Quote: |
Well, I already remarked that theories with massive photon are giving
the same experimental answers that classical electrodynamics in the
corresponding limit.
And also pointed to one example of quantum theory with massive photon
gives the same scattering amplitudes that computed using Feynman
diagrams for QED
|
(...)
| Quote: |
It would be helpful if people would define their terms here. I.e. what
definition of "mass" is being used here? Proper mass or inertial mass?
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I am referring to rest mass (usually denoted by m).
In standard EM theory rest mass for the photon is zero but in other
theories and models it is not.
--
Center for CANONICAL |SCIENCE)
http://canonicalscience.org |
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