Speed of light in a vacuum... not constant?

it says the shape of the photon was changed/ phased. then it clearly said that the speed difference was from passing through a filter.

" The mask, they explain, caused some of the photons in the group to move at a slight angle to the other's causing a slowdown for the group as a whole. Thus, their results are not going to upend one of the basic tenets of modern physics, it is more likely that future researchers will have to make sure lab or astronomical observations are not being impacted by shape changes that occur naturally. "

 

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The first stage in section one where the Bessel Beam is created is inside of a hallow waveguide (that doesn't mean that would make it photons in free space!). The problem is that would mean that it is just affecting the wrong particle! In waveguide theory, it is the electrons that travel along the skin of a waveguide, not light. Think about it. Light at different wavelengths are not going to interact with a material at all, like x-rays for example. Although, electrons would interact with a material at most any wavelength if it was a conductor. Then all they would have done was change the phase of electrons, and then those electrons would have traveled slower than the speed of light before they transmitted a photon in the final stage to a detector. Electrons can travel at a significant fraction of the speed of light, so the photons from them would have arrived afterwards.

How much light interacts with a material would be determined mostly by it's wavelength, and how much electrons interact with a material depends mostly on the type of material, rather it is a conductor or not. Then the only thing the experiment really proves is that electrons can travel a large fraction of the speed of light in a waveguide, just like I have always been saying.

 

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No. The SLM in section C of the diagram shapes the light into a Bessel beam which then travels in free space or air to the arrangement of mirrors that are shown in Section C. There are optical fibres in the other parts of the setup but this part is in free space or air. This experiment does not use a waveguide at all.

Waveguides are mentioned in the explanation at the beginning about the mathematics of the Bessel beam , i.e. involving Bessel functions, but the only things resembling a waveguide in this apparatus are the optical fibres used in "piping" the light to where they want it.

The rest of your post does not make sense, because you have misunderstood the experiment.

 

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Whatever, the people that ran the experiment didn't even understand the laws of physics. I guess it is supposed to make me feel better that they used properties that would describe electrons to predict the behavior of light (sense electrons would be used in a waveguide)?

What doesn't make sense? If you have a light bulb, the electricity excites the filament to make it give off light. The light from a light bulb can heat up any kind of material. The filament would generate heat because of the excitation. Other wavelengths of light, would not heat up a material, because they would not interact with that material at all.

If you had a microwave oven, you could stick a plastic container in there by itself, and it would not heat up. That would be because it is a poor conductor. Then it would not interact with the electrons. Most food in there only gets hotter, because it has water or ice inside of it. Then water is a good conductor of electricity.

On the other hand, if you had a plastic bowl and put it next to a light bulb, it would heat up. The electrons of the bowl still absorb photons, even though it wouldn't take on extra electrons. Since, a plastic bowl wouldn't take any extra electrons, it wouldn't be heated by being bombarded by electrons.

This could just be the first of many bogus experiments that have electrons posing as photons. Like the experiments that discovered gravitational waves from detecting spins in photonic images. They where just looking at electrons, that just happen to have spin and charge. There is no such thing as gravitational waves.

Hell, the only reason why they thought photons are photons to begin with and not electrons was because they traveled the speed of light. Before you know it, there will be an experiment to prove that photons have every single property of an electron...

 

Layman, you're maybe missing the point here. The gist of this work is that if you make photons follow a somewhat helical path, their linear propagation rate is reduced a little. Lurking under the covers is that if you could make the photon path rather more convoluted, you could reduce its linear propagation to zero. Only then we wouldn't call it a photon any more.

 

And that is a lie. The photons are not taking any helical path. According to the claim of the authors, this is a case of manipulating group velocity and demonstrating that photons travel at their group velocity.

No, this too is a lie. There is nothing in this experiment or the relevant theory that suggest that one could reduce the group velocity of a photon to zero. Nor does this experiment or the theory behind it have anything to do with a photon traveling in any way other than a straight line in Euclidean 3D space.

You might call me a troll for correctly identifying your lies, but the original paper is freely available for anyone to check on your lies.

 

Incorrect. Pure water is a poor conductor, but is heated quite effectively by microwaves.

Incorrect. See above. Conduction is not the method by which water is heated by 2.4GHz radiation.

A clear plastic bowl is heated primarily by conduction/convection from the lamp. Since light bulbs are about 4% efficient, direct heat transfer is by far the largest effect.

However, if you had a black bowl, and it was illuminated by a strong distant light source, you are correct in that most of the heating would come from absorption of photons.

 

See this post on the other thread where exchemist said this: "Addendum: I've tracked down something on the average trajectories of photons in a Bessel beam and it looks indeed as if they are helical: http://arxiv.org/pdf/1304.1276.pdf"

 

I stand corrected. If we describe this using classical mechanics and not quantum mechanics, we do infer helical paths.

 

I didn't say pure water. I just said water. Your not going to have pure water in your food! It would physically impossible! The food itself would make it impure! What I stated was a fun fact that I picked up a long time ago. I didn't come up this idea myself.

I didn't say conduction was a method water was heated. I said that the food is heated by conduction from the water that is irradiated.

Incorrect, it would be from radiation.

The color black absorbs all frequencies of visible light! That is why it would be black! A white bowl would also absorb all the frequencies of light, but it would also emit all those frequencies back as well. That is why it is cooler to wear the color white! That is why it gets hotter wearing black!

I will give you an example. Your microwave is made out of plastic. The inside of the microwave and the door isn't hot after using it. Then the location of where you placed the bowl of food would then be hot. The food itself would be hot, but the outer rim of the bowl wouldn't necessarily have to be hot. Therefore, most of the time you haven't microwaved something that long, you can touch the outer rim of the bowl to grab it without protection, because it won't be as hot.

 

Here's another example, the sun put's out electromagnetic radiation out in the form of photons. On a hot day, the concrete outside heats up. It will burn your feet if you try to walk on it bare foot. Then if you stick dry concrete in the microwave, it will not heat up. The same could go for most types of rocks as well. Then rocks should heat up in the microwave if all electromagnetic radiation was photonic energy (even though photons don't have charge that would create magnetism).

 

Another example, metals left out in the sun will oxidize over long periods of time. Then metals in the microwave will spark and combust fairly quickly. That would have had to have had been a good thing for cars and airplanes.

 

Glad to see your random gibberish generator is working again, Layman.

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Try it yourself. Put pore distilled water in your microwave. It will heat as fast as any other water. How do you explain that?

Some are made of plastic; some are made of metal. Yet even the insides of metal microwave ovens do not heat up. How do you explain that?

 

Distilled water that you buy at the store is NOT pure water.

Not sure how they invented microwave safe metals. They are most likely not good conductors.

You should read the wiki on microwaves. They heat up things by changing the dipole moment. That is by changing the poles of the molecules in a sense. When atoms absorb photons, it changes the energy level of the electrons so they go into different orbitals. Having different orbitals of electrons wouldn't change the dipole moment. Although, if you added electrons to an atom so that it became an ion, that would change the dipole moment.

 

So try it with the purest water you can get. Get a tank of hydrogen and burn it; the result will be pure water. Distill a gallon of water yourself; the result will be pure water. All will warm just as fast in a microwave.

No, they are great conductors. But their skin depth is such that very little of the metal carries current; thus the overall heating is low. As an exercise, calculate the skin depth in steel at 2.4GHz (microwave frequencies.) Note that the better the conductor the shallower the skin depth - so gold would be an ideal metal to build a microwave out of. The walls would heat very little and most of the energy would be reflected back and forth. Gold is a bit expensive so most microwave enclosures are made out of aluminum or high-conductivity steel.

Not quite. They cause polarized molecules (like water) to try to rotate quickly to align with the rapidly changing electric field in the microwave radiation. (This is called dielectric heating.) This motion imparts motion to nearby molecules, and of course such motion is what we call heat.

Microwaves don't have enough energy to bump electrons up in orbitals. If they did you'd see re-radiation at a different frequency when the field was removed, which we don't see.