[General] Nature of Light and Particles

Fri Apr 3 17:54:36 PDT 2015

Hi John Macken

If we suppose the dipole in your though experiment is a one wavelength
dipole with the half wave point at the center, (at the frequency of photon
emission), the equatorial photons emitted would be blue shifted on the
advancing side and redshifted on the retreating side of the spinning dipole.
The blue shifted emission region would contain more energy and therefore
more momentum regardless of spin, and the spinning dipole would be slowed
due to this effect. This effect becomes even easier to understand if the
photon wavelength is shorter related to the dipole length. In the equatorial
case, for the slowing of the spinning dipole, longitudinal momentum is
imparted to the photons (tangential with respect to the dipole) in lieu of
spin momentum. I am thinking that in your though experiment example, if any
spin momentum is imparted to the photons, it will be equal parts of left and
right spin, yielding a plane polarized photon. But since it would have the
blue shifted and redshifted regions during emission, even equal amounts of
left and right spin angular momentum imparted to the photons would slow the
dipole.

Thoughts?

Chip

From: General
[mailto:general-bounces+chipakins=gmail.com at lists.natureoflightandparticles.
org] On Behalf Of John Macken
Sent: Friday, April 03, 2015 5:49 PM
To: 'Nature of Light and Particles - General Discussion'
Subject: Re: [General] Nature of Light and Particles

Chip,

I am responding to your questions about the spin of a linearly polarized
photon because I intend to include this subject in my paper if my abstract
is approved for inclusion in the Nature of Light conference.  I am going to
first present a thought experiment.  

Suppose that we have a rotating electrical dipole which physically consists
of two opposite polarity electrical charges at opposite ends of a rotating
rod.  The rotation is around the center of the rod and the rotation axis is
perpendicular to the rod length dimension.  The rotating dipole will emit
electromagnetic radiation into a classical rotating dipole emission pattern.
The photons emitted along the axis of rotation will be circularly polarized
with the rotation direction the same as the rotation direction of the rod.
If the rotating dipole is visualized in a vacuum and an inertial frame of
reference, then it can be shown that the angular momentum being carried away
by the circularly polarized photons emitted along the axis slows down the
rotation speed of the dipole by the exact amount that corresponds to  the
energy being carried away by the circularly polarized photons.  So far there
are no surprises.

Now suppose that we look at the photons being emitted in the equatorial
plane of the rotation.  The well-known emission pattern of a rotating dipole
emits linearly polarized photons in this plane.  If these photons are
carrying away equal amounts of the two opposite spin rotational directions,
then the rotating dipole is experiencing no net loss of angular momentum
which implies that the rotating dipole does not lose any energy when it
emits equal amounts of photons with opposite spins.  A perpetual motion
machine could be made if a special reflector was made which only allowed
light emitted in the equatorial plane escape.  

This obviously must be wrong.  The implication is that linearly polarized
light is carrying away angular momentum also and the angular momentum always
is such that it slows down the rotating dipole.  The proposed answer is that
linearly polarized photons are carrying away orbital angular momentum (my
laser background)  and the rotation axis is perpendicular to the photon's
propagation direction.  This should be experimentally provable, but a
practical experiment will be difficult devise.

John M.             

From: General
[mailto:general-bounces+john=macken.com at lists.natureoflightandparticles.org]
On Behalf Of Andrew Meulenberg
Sent: Friday, April 03, 2015 10:27 AM
To: Nature of Light and Particles - General Discussion; Andrew Meulenberg;
Jean-Luc Pierre P.
Subject: Re: [General] Nature of Light and Particles - Request

Dear Chip,

Since I have been having this discussion with someone (Jean-Luc Paillet) in
a different context, I thought that I would take the time to try and find a
paper that contained a statement that I had interpreted to mean that a
linear-polarized photon still had a spin of 1. 

I found what I think may be what I had seen (attached). However, now that I
look more closely, I am not sure that it is referring to a photon or a
collection. Perhaps someone more mathematically sophisticated can look at
sections 6.7 (for circular-polarization) and 6.8 (for linear-polarization)
of the attached and let me know if it can refer to single photons as well as
collections. "We recover the classical result derived in Section 6.7: the
spin is in the direction of propagation of the wave."

Jean-Luc referred to the 3rd from last paragraph of
http://mathpages.com/rr/s9-04/9-04.htm , which states that linear-polarized
light is only balanced circular-polarized light. However, it further states
that individual photons will register as +/- hbar. Thus, it is a
superposition of 2 states, rather than a 3rd state. If this is the case,
does the E = n h nu relation come into play? If so, then I assume that
spectrometers could respond differently to  linear- and circular-polarized
light of the same energy (with n = 2 and 1 respectively). On the other hand,
since w = w1+/- w2, a spectrometer might see only the sum of the two
coherent photons (a thermally stable BEC?). It is an interesting problem
that I see no convincing solution to.

Andrew

______________________--

On Fri, Apr 3, 2015 at 7:26 PM, Chip Akins <chipakins at gmail.com
<mailto:chipakins at gmail.com> > wrote:

Hi John W

The intent of this line of discussion is to probe more deeply into the
structure of the photon and to address polarization entanglement
experiments.

A thought and some questions for you John.

First some background.  As I understand it Quantum physics posits a
superposition of spin states as a cause for planar polarization. In order to
reach a more causal explanation, can we then envision two fields within the
photon, spinning opposite directions, and constructively interfering only in
a plane, which is dependent on their spin phase? 

Are you familiar with Joy Christian's work?  He writes that two
non-commuting rotations (spin operators) as local variables, exactly
duplicate the predictions of Quantum mechanics and satisfy Bell's
inequalities in precisely the same way. I have checked some of the math and
so far it seems to be quite accurate. In both of these approaches, two
oppositely rotating fields would apparently satisfy these physical aspects
of the theories. ???

Christian uses a Clifford algebra to illustrate his theory.  Have you had
the chance to compare that with the work you are doing using Clifford
algebra to in your new theory of light and matter?  Specifically have you
had any opportunity to check to see if two opposite, (non-commuting local)
spins caused by your framework would also satisfy Bell's inequalities? Or
CHSH inequalities?

Of course you can see the underlying reasons for these questions.  One
underlying reason is to discover if two equal and oppositely spinning
fields, confined within the photon, can explain polarization.  In both,
quantum physics, and Christian's theories, it seems that two opposite spins
are required, hinting that we would need those two opposite physical spins
to be possible in a physical model of the photon.

The other underlying reason is to discover if non-commuting (rotation) local
variables can potentially be the cause for the appearance of entanglement.

Thoughts?

Chip

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