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New magnetic component discovered in the Faraday effect

phys.org

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Re: New magnetic component discovered in the Faraday effect

#21

Post by gsf_emergency_6 »

magphys wrote: post #3

> To quantify this influence, the team applied their model to Terbium Gallium Garnet (TGG), a crystal widely used to measure the Faraday effect. They found that the magnetic field of light accounts for about 17% of the observed rotation at visible wavelengths and up to 70% in the infrared range. Nearly 20% seems already significant, but 70%?! that's massive.

Seems to be a minor typo . Paper:

>17.5% of the measured value for Terbium-Gallium-Garnet (TGG) at 800 nm, and up to 75% at 1.3 µm.

Here's what the crystal looks like

https://www.photonchinaa.com/tgg-terbium-gallium-garnet/

Here's transmission plot (UV-IR)

https://www.samaterials.com/terbium-gallium-garnet-crystal.h...

Note there's almost no effect on transmission

Relevant? https://dspace.mit.edu/handle/1721.1/51819

Re: New magnetic component discovered in the Faraday effect

#22

Post by sosodev »

canjobear wrote: post #19
namanyayg wrote: post #2

We intuitively think in particles and see a world of billiard balls colliding with one another. But actually everything is merely waves and fields. There's going to be a time where humans finally reconcile the quantum with the newtonian -- and I can't wait for that day

There's no problem reconciling the quantum with the Newtonian. Quantum mechanics recovers Newtonian mechanics in the appropriate limit. The problem is reconciling the quantum and the Einsteinian.

But there’s no quantum explanation of gravity, right?

Re: New magnetic component discovered in the Faraday effect

#23

Post by arthurcolle »

sosodev wrote: post #22
canjobear wrote: post #19

Earlier quoted context omitted.

There's no problem reconciling the quantum with the Newtonian. Quantum mechanics recovers Newtonian mechanics in the appropriate limit. The problem is reconciling the quantum and the Einsteinian.

But there’s no quantum explanation of gravity, right?

Classified

Re: New magnetic component discovered in the Faraday effect

#24

Post by lmpdev »

sosodev wrote: post #22
canjobear wrote: post #19

Earlier quoted context omitted.

There's no problem reconciling the quantum with the Newtonian. Quantum mechanics recovers Newtonian mechanics in the appropriate limit. The problem is reconciling the quantum and the Einsteinian.

But there’s no quantum explanation of gravity, right?

At this point we have several

They’re all largely untestable though

String theory, LQG, half a dozen others

Re: New magnetic component discovered in the Faraday effect

#25

Post by ggm »

fragmede wrote: post #8
gucci-on-fleek wrote: post #6

Earlier quoted context omitted.

Hmm? The double slit experiment definitely shows that particles are waves—weird quantum waves, but still waves.

what happens when you only send a single photon down the line though?

I've always wondered what degree of confidence exists amongst the cogniscenti that a single photon event happened. I tend to think the criteria of measurement here would suggest the most likely outcome was a shitload more than 1 photon, and that all the "but we measured we can see one only" measurements are themselvs hedged by a bunch of belief.

That said, I do like the single photon experiment, when it's more than a thought experiment.

Re: New magnetic component discovered in the Faraday effect

#26

Post by gsf_emergency_6 »

CamperBob2 wrote: post #11
magphys wrote: post #3

> To quantify this influence, the team applied their model to Terbium Gallium Garnet (TGG), a crystal widely used to measure the Faraday effect. They found that the magnetic field of light accounts for about 17% of the observed rotation at visible wavelengths and up to 70% in the infrared range. Nearly 20% seems already significant, but 70%?! that's massive.

How did no one notice that before, and what else have they (we) missed?

If I'd to guess: all that exp. characterization to-date has revealed no anomaly (See my other comment)

This team might have looked at bandstructure. or not (they didn't say, & I'd guess not)

Re: New magnetic component discovered in the Faraday effect

#27

Post by jasonwatkinspdx »

thaumasiotes wrote: post #4
namanyayg wrote: post #2

We intuitively think in particles and see a world of billiard balls colliding with one another. But actually everything is merely waves and fields. There's going to be a time where humans finally reconcile the quantum with the newtonian -- and I can't wait for that day

> But actually everything is merely waves and fields. The two-slit experiment says otherwise.

It does not. It shows that individual photons self interfere, so they cannot be idealized particles.

Re: New magnetic component discovered in the Faraday effect

#28

Post by danparsonson »

fragmede wrote: post #8
gucci-on-fleek wrote: post #6

Earlier quoted context omitted.

Hmm? The double slit experiment definitely shows that particles are waves—weird quantum waves, but still waves.

what happens when you only send a single photon down the line though?

It's a wave of probability, that interferes through the slits and then collapses into a probability of one somewhere along the wavefront at the point of detection. Whatever that means :-)

Re: New magnetic component discovered in the Faraday effect

#29

Post by dcl »

thaumasiotes wrote: post #4
namanyayg wrote: post #2

We intuitively think in particles and see a world of billiard balls colliding with one another. But actually everything is merely waves and fields. There's going to be a time where humans finally reconcile the quantum with the newtonian -- and I can't wait for that day

> But actually everything is merely waves and fields. The two-slit experiment says otherwise.

Are you getting confused with the photoelectric effect experiment?

Re: New magnetic component discovered in the Faraday effect

#30

Post by gucci-on-fleek »

fragmede wrote: post #8
gucci-on-fleek wrote: post #6

Earlier quoted context omitted.

Hmm? The double slit experiment definitely shows that particles are waves—weird quantum waves, but still waves.

what happens when you only send a single photon down the line though?

As the other comments have already mentioned, it interferes with itself, so you still observe the same interference patterns [0] [1]. Which admittedly seems impossible at first, but so does the rest of quantum physics.

[0]: https://www.feynmanlectures.caltech.edu/III_01.html#Ch1-S5

[1]: https://en.wikipedia.org/wiki/Wave%E2%80%93particle_duality#...

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