Electron spin

@deepthought said
That was from memory, but a reference for this is easy to provide. This is the Particle Data Group's listing for Gauge and Higgs Bosons, the relevant quantity is listed as J.

http://pdg.lbl.gov/2019/tables/rpp2019-sum-gauge-higgs-bosons.pdf

That doesn't say photons spin.
Why would something massless spin?

@humy said
Arr, at least, you have just admitted you think there may be no proof. Just as I suspected.
It took my about 30 seconds of my time to google search and find this about that experimental proof;

https://core.ac.uk/reader/49287350

https://www.sciencedaily.com/releases/2016/09/160926115345.htm

This just shows your delusional arrogant complete ignorance on the subject.

Your first link doesn't work and the second says "generated by light on a silicon chip." That isn't light in general. That is a specific application.

What is the measurement? Seeing the result is important for knowing they aren't making it up, right? If I claimed I measured something and never shared the results with you would you believe me?

@metal-brain said
That doesn't say photons spin.
Why would something massless spin?

J is the total angular momentum, since a photon is an elementary particle this is the spin. It gives the spin as 1.

Why do you think spin is contingent on mass?

@deepthought said
J is the total angular momentum, since a photon is an elementary particle this is the spin. It gives the spin as 1.

Why do you think spin is contingent on mass?

How are they getting angular momentum from a graviton? Nobody has ever observed a graviton. We don't even know for certain it exists.

@metal-brain said
If it isn't speed being measured what is being measured?

As already explained many times before, the effect of an applied magnetic field can be measured and is consistent with what you would expect from the particles' spin.

@metal-brain said
Your first link doesn't work and the second says "generated by light on a silicon chip."

The first link opens for me just fine and my second link says a lot more than just the words "generated by light on a silicon chip." because it also says, among other things;

"From the measurement results, we were able to calculate the spin angular momentum carried by a single photon,"

and

"their experiment provides the first unambiguous measurement of the spin angular momentum of photons "

Do you deny this?
Do you now finally accept I have shown you a link that explains the experimental proof of the spin of a photon?
If not, explain...

What is the measurement?

You want me to define the meaning of the words "the measurement"?
If what you are really asking is what is BEING measured, its spin.
If what you are really asking is HOW they measured it, just read the link and see for yourself. I won't babysit you.
If neither the above, what are you really asking here? I honestly don't know.

Seeing the result is important for knowing they aren't making it up, right?

The results are explained in that link for you to see for yourself. I won't babysit you.

@metal-brain said
How are they getting angular momentum from a graviton?

Who here suggested this?

@kazetnagorra said
As already explained many times before, the effect of an applied magnetic field can be measured and is consistent with what you would expect from the particles' spin.

Applied magnetic field?

How many more jargon terms are you going to use to avoid explaining spin measurement? What is the measurement?

@humy said
Who here suggested this?

It's in the link I posted earlier. The Particle Data Group included it, probably because there are empirical bounds on its mass (< 6.0E-29 eV). The value for the spin is theoretical. I imagine the bound on the mass comes from checking for deviations from the inverse square law.

http://pdg.lbl.gov/2019/tables/rpp2019-sum-gauge-higgs-bosons.pdf

@humy said
The first link opens for me just fine and my second link says a lot more than just the words "generated by light on a silicon chip." because it also says, among other things;

"From the measurement results, we were able to calculate the spin angular momentum carried by a single photon,"

and

"their experiment provides the first unambiguous measurement of the spin angular ...[text shortened]... ht? [/quote]The results are explained in that link for you to see for yourself. I won't babysit you.

That article also says this:

"To measure this twisting caused by light, a small silicon beam inscribed with a high quality optical cavity is attached to the waveguide. This provides high measurement sensitivity to the rotation of the beam and the waveguide.

The silicon beam is like the board of a seesaw and the waveguide is like the shaft in the center. When light twists the shaft, the latter rotates and the seesaw tilts, and this is detected by the optical cavity. By changing the polarization of input light periodically, Professor Mo Li's team observed that the nanobeam rotated periodically as well, revealing the optical torque applied on the waveguide."

He uses the word "rotation" and "rotating". How do you know a beam or nanobeam is rotating? What is a nanobeam? How many jargon terms did people make up to avoid explaining anything?

Didn't you previously have a problem with angular momentum being called rotation?

@deepthought said
It's in the link I posted earlier. The Particle Data Group included it, probably because there are empirical bounds on its mass (< 6.0E-29 eV). The value for the spin is theoretical. I imagine the bound on the mass comes from checking for deviations from the inverse square law.

http://pdg.lbl.gov/2019/tables/rpp2019-sum-gauge-higgs-bosons.pdf

That article is purely theoretical. Nobody knows a graviton exists. Spin is apparently just theory and nothing more.

@metal-brain said
That article also says this:

"To measure this twisting caused by light, a small silicon beam inscribed with a high quality optical cavity is attached to the waveguide. This provides high measurement sensitivity to the rotation of the beam and the waveguide.

The silicon beam is like the board of a seesaw and the waveguide is like the shaft in the center. When light t ...[text shortened]... ining anything?

Didn't you previously have a problem with angular momentum being called rotation?

What is a nanobeam?

Look up "nano" and then "beem". I won't babysit you. If you don't understand very basic scientific terminology and forever be unwilling to learn for your self preferring to just keep shouting "LIAR" instead then that just proves how ignorant you are of it BY CHOICE and despite your incredible delusional arrogance to the contrary.

Do you deny my source of information or deny there is experimental proof of photon spin just because you don't understand it?

Didn't you previously have a problem with angular momentum being called rotation?

No. I have never had a problem with that especially with spinning tops. Back to Electrons, which that link wasn't about; Electrons spin but it would be no quite correct to say they 'rotate'.

@metal-brain said
Applied magnetic field?

How many more jargon terms are you going to use to avoid explaining spin measurement? What is the measurement?

If magnetic fields are too much jargon for you then I'm afraid you will have to brush up on your physics knowledge before you attempt to understand what spin is.

@kazetnagorra said
If magnetic fields are too much jargon for you then I'm afraid you will have to brush up on your physics knowledge before you attempt to understand what spin is.

That is your psychological projection.

You do not know what one is yourself. You are just hopping from one jargon term to another endlessly to pretend you understand what you clearly do not.

@humy said

What is a nanobeam?

Look up "nano" and then "beem". I won't babysit you. If you don't understand very basic scientific terminology and forever be unwilling to learn for your self preferring to just keep shouting "LIAR" instead then that just proves how ignorant you are of it BY CHOICE and despite your incredible delusional arrogance to the contrary.

Do you de ...[text shortened]... which that link wasn't about; Electrons spin but it would be no quite correct to say they 'rotate'.

There isn't even a wikipedia page about it.
You are a liar!