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["Your start point is when we say the photon is spinning what do we really mean because it isn't your naive 3D classical thing."]


So this “spin” refers to an object acting like it has angular momentum, but without the object actually rotating like it would in classical physics?

Yes pokey correct the energy is rotating but not in our 3D world. It is somehow spinning hidden behind, under or inside our universe. This is common to all electromagnetic signals of which light belongs to that you require 4 dimensions.

You can only write them as equation of either the electric field E[x,y,z,t] or magnetic field B[x,y,z,t]. The time component is because the EB fields are disappearing in and out of our 3D world. That oscillation occurs regardless of the fact that the signal is travelling at the speed of light and according to us time has stopped.

When we draw the usual 4D representation of the EM wave most layman either haven't run across the concept that time is stopped at c so how does the EB wave know when time to oscillate at as it moves thru space.

Here is the usual image


Do you see the hand wave we do the EB fields are changing in time but time is stopped at c so how are they changing.

The real problem with the drawing is the vertical lines we draw are a lie there they dont exist like that it's just a single line with the EB intensity varying on that single line. If you drew a line varying from black to white in a set length and back again that is what it really looks like. Those arrow represent the intensity and we have taken them into a 3D space which is a lie.

Lets see if I can do ascii art on a single text line

----****@@@@****----****@@@@****-----

The heavier fatter characters represent an increase in either the E or B field whichever we are looking at but its a single line

I find the 3D image above very misleading to people because they think the waveform really is taking up 3D space. The truth is the black line the arrow base is on is the only real thing the vertical arrows just represent intensity to some arbritrary scale of that black line.

No problem with that, except that you are also saying that the photon is not actually spinning in the sense that we would understand it in 3D space. Doesn’t that imply that the RF is outside our dimensions?

Doesn’t that take us back to “square one”. There’s a RF there somewhere, but we can’t relate it to our 3+1 D.

This sounds as though it would be difficult to test.

Almost it is valid to exactly one point in our 3D space being the centre of the spin and it is thru that one point the energy enters and leaves. It is exactly the same for the centrifugal case.


No as per above it is related thru exactly one point and thru the energy exchange. What you are really saying is you can't relate it to other points in space and that is true. However that situation isn't unique corner a car hard and that energy and force has no meaning to anyone not in the car. The cornering car energy has meaning to you if you crash into it and that is the same for your photon.

I still get the feeling you think reference frames should be good and usable universally and it is not at all unusual for that not to be the case even in your classical world.It's funny if I asked you how a bird can sit on a high voltage power line you would probably recite an answer but you struggle with the same situation involving motion. It's almost as if you feel they should be more connected.

So was the Higgs field

If you hadn't realised the detection of GW150914 creates the same problem you need a dimension for space to contract in and out of for the gravitational wave. That was the problem Paul was struggling with into what is space stretching and contracting.

Its funny we say it proved Einstein right but he actually went backward and forward on the gravitational wave thing over his life because it implied the extra dimension in his GR was real, something he struggled with. He wavered throughout his life on whether the extra dimension in his formulation was just part of the mathematics or real. In the end he sort of adopted the shut up and calculate approach.

I'm going to suggest this as a training aid for you.

perhaps instead of writing this



try something like this


you know its funny because we say it proved Einstein was right
but ...

before you post it , read it , and think about how we talk to others.

this would greatly help us to understand the things you are
telling us.

sometimes the way you write is a little cloudy.

Thanks for that.

I will try but English is still not the most natural thing for me, even with speach.

I’m trying to get my head round this, so I’m going to break it down.

1. A photon has spin.
2. This is not the same as classical spin.
3. Particle spin causes a quon to behave as though it had angular momentum, but without actually rotating.
4. Although not rotating, a photon has an axis of spin.
5. This axis provides the only point at which contact is made with our 3+1D, such that a RF can be established for the photon.

yes


We need to put limits on this. It is doing something that when the particle interacts with our classical world it appears to have angular momentum.

You really struggle with the reality thing

Lets do this with throwing a ball off a merry go round which is something far more down to earth you deal with.

See the problem you can't identify what is actually spinning the mathematics works equally. If you measure the forces it does not arise from any physical interaction between the objects but based on the past history of it's movements.

Spin even in your classical world makes no real sense and so in your classical physics you have to introduce it's forces in a totally fictional way. When you corner your car hard you experience forces and motions that make no sense to an observer unless they observe your motions before hand.

So lets take your car cornering hard and I wasn't observing you but suddenly decided to measure. I am advanced race and suddenly teleported into the car to measure and I would go woah where did these forces come from. At the moment I decided to measure the forces make absolutely no sense to me because I am not GOD I can't see what your past motions were. If we had teleportation that would be one of the dangers teleporting into a spinning situation and getting slammed sideways into things.

What you get comfortable with in our classical world is being able to see the past history of things before we interact with them. Generally we only get caught out jumping on or off moving things. Always fun watching people fall over getting on and off escalators, the young ones call it escalator fail.


It is rotating just not in your classical way that you can view the path of the past motions. Besides being able to see the motion it makes every bit as much sense or as little sense, as your classical spin the forces and energy play out the same way.

So Quantum spin is every bit as real or as imaginary as your classical spin


Which is exactly the same for the centripetal case and that frame has no relevance to a stationary observer it relates only thru calculations on energy.

So I guess I should ask is classical spin real or imaginary?
If I can't see the previous motion how do I know if an object is classically spinning?

both the ball and the merry go round are spinning.

your gif image shows this.



spin makes perfect sense to my classical world because its
obvious that everything in the cosmos is spinning.

everything!

duhhh.

at the moment that a photon is emitted it inherits its spin
from the spin of its emitted source.

that spin is certainly not claimable by non classic physics
nor is it only calculable by non classic physics.

the ball is rotating 1 revolution for each 1 revolution
of the merry go round.

the side of the ball facing away from the center of the
merry go round is traveling faster than the side of the ball
facing towards the center of the merry go round.

the ball when released is like an unbalanced wheel.

so when the ball is released the ball will continue to spin at the same rpm rate as the merry go round.

what could possibly be so hard to figure out about that?

Analogies often break down because, at best, they can be only partially analogous to the real thing.

The throwing a ball from a roundabout analogy works only if the spinning frame is a 3D entity. If we were considering a real roundabout, constructed in such a way that we could either spin the roundabout relative to its base, and the wider environment; or keep the roundabout stationary relative to the environment and spin the base, relative to roundabout and environment; there would be no difference in the angular direction, relative to the base, in which the ball would go.

Jus' sayin'

I am not sure why you think it is an analogy?

Explain why you don't think it is real

Paul your science understanding is so bad at times it's like watching a train wreck in slow motion. I never know whether to look away or try and help.

Most of your statements are bad but this one is a train wreck.

I take it you are saying photons have classical spin?

So I have a torch, globe or led makes no difference. So explain to me when the photons spin in the beam that shines out the front relates to the torch.

To extend the problem I have a laser pointer emitting a laser beam describe the photons in the beam spin for me please.

Throwing a ball from a roundabout is equivalent in every detail to a spinning photon. Somehow I have grave doubts about that.

of course they do.



when the photon leaves the light source.



the photons in the beam have inherited the motion of the
light source ( the laser ) as they were emitted.

and they will continue to have that inherited spin until
some outside influence acts against the spin like the
influence from a magnetic field or a gravity field
that causes its spin to change.

if you don't believe that a photon inherits the spin of
the light source then perhaps you should explain why it
would not.

lets put a laser pointer in a drill press and turn the
laser pointer on , then turn the drill press on at its highest
speed... for example lets say the drill press is rotating
the laser pointer at 10,000 rpm.

do you seriously believe that the light being emitted
from the laser pointer will not inherit the spin of the
laser.

if so please tell me why the emitted photons would not be spinning at the same rpm as the laser pointer.

But what in the light source the atoms orientation and spin, the actual macro spin of the torch. As I said I can't really understand what you think your spin relates too.


Say what ... can you give me an example of an electric or magnetic field deflecting light?


Ummm because photon spins aren't classical at all


Spinning the source does nothing and it's easy to test and directly conflicts with your idea.


Not only do I believe it you can show it by countless experiments. Light from quasars and pulsars from space which are spinning unbelievably fast have no special super fast Paul spin on them.


No point me explaining it you always make your own physics up and you already know you won't accept it.

Lets just give you two words and a fact you may decide to search. The words are helicity and chirality. The fact is for massless particles the helicity always equals the chirality which it does not for particles with mass. I can't help beyond that because I am not sure how helicity and chirality works in your physics.

Well they both involve spin and I can't give you an analogue of spin. Something either spins or it doesn't.

The roundabout example shows the relationship of mass movement with spin. So if I have something I can't or haven't seen the motion of I can identify spin if we can understand the motions.

Lots of sports people like pool or billiards player, some soccer players (Bend it like Beckham), most tennis players, some baseball pitchers and many layman know how to use spin because it behaves the same in all physical situations.

You can even write the equations of the sport
https://www.grc.nasa.gov/www/k-12/airplane/straj.html => Bending a soccer ball.

Spinning has no analogs and it simply has equations of what happens whatever the situation. So if I have something I say is spinning it might be important to check it behaves the same.

I’m trying to get my head round this.

1. The laser pointer is rotating at 10,000rpm.
2. Does the emerging beam rotate at 10,000rpm?
3. Is this rotation imparted by the rotation of the emitting “element”?
4. Is this rotation imparted by “friction” between the laser lens and the light?
5. Wouldn’t rotation of the beam impart helical movement to the photons, rather than causing each photon to spin, but maintain a straight course?
6. If 5 is correct, would you see this as an example of photons travelling faster than “c”?

Returning to a previously mentioned inconsistency:



If time can be measured it must be something. This is inconsistent with my previous intuitive thought.

I wasn't expecting you to have trouble with this one Bill S.


Nope it doesn't it holds no relationship to your classical world .. EB fields don't see Bill S

I won't lie to you and give you the usual hand wave and tell you the photon is a point and you can't spin a point

The extension of the exercise is if you run forward with the torch or laser pointer the light beam doesn't leave faster than c either. Nor if you run backwards do the photons leave the torch slower.

I am going to do a hand wave for the moment and say in general you can't control the emission rotation it is entirely probabilistic. So I am going to introduce a new term called Spontaneous Emission of a photon from an atom and tell you the orientation is random under that condition.


This is the hand wave if I prepare a special form of photons I can stimulate an emission from an atom. The emitted photon will inherit the spin characteristics of the photon that stimulated it and we sometimes do this in lasers to produced a polarized laser beam.

So when you said "element" you were probably thinking classical world stuff but no we do some trickery with QM to control the spin.


Spinning the lens has a funny effect it will slow the light down and can shift the photon slightly but it will not impart rotation to the photon. Even if you make the lens long like a cylinder. The process is called photon drag.

http://physicsworld.com/cws/article/news/2011/jul/05/rotating-cylinder-puts-a-new-spin-on-slow-light


5 doesn't happen the emission process doesn't see classical movements and 6 is correct if it could happen.

I will give you the only way you can control photon spin classically its called a polarization and you see it a lot for layman in glasses. So you actually filter out all the light that doesn't match the orientation you desire at the cost that the light emerging is diminished in intensity because you select only the photons with the spin you want.

Even in a laser beam the photons would leave with a random spin unless you put a polarizer in the system in one of a number of forms. However usually because of the design of the partial mirrors at best you usually get partial polarization out of an unpolarized laser. I doubt you can get a truely random one like normal incandescent process because of the stimulated emission.

Finally fixing the hand wave there is a QM effect predicted and experimentally verified called Delbrück scattering. It's fleeting but it might be possible to extend the deflection with lots of QM trickery.

Excluding Laser, Masers and some QM stuff and holding to your classical world we can make this statement.

Finally if you want to see the full story this wiki page is one of the best going around but OAM will probably be confusing to you and why not all spins interact with matter the same way (https://en.wikipedia.org/wiki/Angular_momentum_of_light).

I'm not sure what you were trying to communicate when
you wrote the above orac.



Im going to guess that the word you meant to use was
attract vs deflecting.

try thinking about a cathode ray tube as in a old style
tv tube ...




a beam of laser light is an electromagnetic wave.

a electric magnetic field can bend and spin a electromagnetic wave.




a magnet can bend a laser beam.





that's classic.



BS

lets see a link to the test you speak of... LOL

or should I simply take your word for it...