Energy Photon

[swansont]

42 minutes ago, Itoero said:

That's because refraction, diffraction, reflection, doppler effect are only about observable waves. Scattering is normally about particle behavior but it's also used to describe wave behavior.

No, that's utterly false. EM radiation outside of the visible range undergo these effects. Why would they not?

42 minutes ago, Itoero said:

"Scattering is a general physical process where some forms of radiation, such as light, sound, or moving particles, are forced to deviate from a straight trajectory by one or more paths due to localized non-uniformities in the medium through which they pass." Scattering is a big word...it refers to particle and wave behavior.

And refraction is not due to localized non-uniformities in the medium, it's due to the medium itself.

42 minutes ago, Itoero said:

Fermat's principle is the principle that the path taken between two points by a ray of light is the path that can be traversed in the least time.  It's a ray of light (observable light), it's not about photons.

What does that have to do with whether or not this happens outside of the visible range? And where's your evidence that refraction doesn't occur outside of the visible range?

42 minutes ago, Itoero said:

Why outside visible range? You can see how light refracts in water.

Because you f***ing made the claim about the visible range. More than once. Do you not recall this? Go back and reread the thread. EM radiation effects are not limited to the visible spectrum.

42 minutes ago, Itoero said:

Ok but there position/direction still decides if they hit a target or not...it's not random. And it doesn't matter, when photons do hit the target, they scatter.

So why does the refraction not depend on the thickness of the target? If there are more targets, you should get more refraction. You should get some light not refracting at all for a thin target, and more and more light refracted as the target gets thicker. i.e. it should behave like scattering. But it doesn't.

42 minutes ago, Itoero said:

Of course it does. But in order to know why refraction is an elastic process you need to study the elastic scattering of the photons.

The interaction photons-H2O causes Rayleigh (elastic) scattering in our atmosphere but when the concentration H2O rises (to form liquid water) you don't call the interaction photons-H2O to be scattering anymore...why not?

Because it's not scattering. Rayleigh scattering and refraction are two separate effects. Rayleigh scattering is explained in terms of particles, while refraction is explained in terms of the bulk medium. Perfectly consistent with the definition that you provided.

If you have Rayleigh scattering, not all of the light is scattered. You get more scattering as the optical thickness increases, which is why the sun near the horizon looks progressively redder as it approaches the horizon. The amount of scattering depends on the path length (Beer's law). You don't get that behavior from refraction.

[Strange]

57 minutes ago, Itoero said:

Ok but there position/direction still decides if they hit a target or not...it's not random.

No one said it is random. You made that up.

[Itoero]

On ‎1‎-‎11‎-‎2017 at 2:29 PM, swansont said:

But you are using a change in direction to conclude scattering. 

Yes...that's the definition of scattering.

[Strange]

3 minutes ago, Itoero said:

Yes...that's the definition of scattering.

No it isn't. If you are going to be that sloppy, you might as well say that "localized non-uniformity" or "medium" is the definition of scattering

"Scattering is a general physical process where some forms of radiation, such as light, sound, or moving particles, are forced to deviate from a straight trajectory by one or more paths due to localized non-uniformities in the medium through which they pass."

https://en.wikipedia.org/wiki/Scattering

Please stop making up your own definitions and your own physics.

And stop pretending people said things that they didn't. https://en.wikipedia.org/wiki/Straw_man

[ExperimentalPhysicist]

On ‎7‎/‎10‎/‎2017 at 5:46 PM, Itoero said:

I read the kinetic energy of a photon goes to infinity when a photon reaches c. Is that possible?( E=hf )

Does the wavelength/frequency of a photon changes depending on the medium?

Dude C is constant speed of light its docent "reach C" and it doesn't change on the medium it you just believe it changes but really it remains constant that's why there a C in E=MC2

[Strange]

For comparison:

• Refraction is the change in direction of wave propagation due to a change in its transmission medium. (https://en.wikipedia.org/wiki/Refraction)
• Reflection is the change in direction of a wavefront at an interface between two different media so that the wavefront returns into the medium from which it originated. (https://en.wikipedia.org/wiki/Reflection_(physics))
• It is defined as the bending of light around the corners of an obstacle or aperture into the region of geometrical shadow of the obstacle. (https://en.wikipedia.org/wiki/Diffraction)

So, by your "logic", a change in direction is the definition of refraction, reflection and diffraction. But of course, these are all different things, and so that definition is incomplete.

[swansont]

11 minutes ago, Itoero said:

Yes...that's the definition of scattering.

That only works if the only way to change direction is scattering.We know e.g. that gravitational lensing and diffraction will change a photon's direction. Are they scattering? 

[Mordred]

17 minutes ago, Strange said:

For comparison:

• Refraction is the change in direction of wave propagation due to a change in its transmission medium. (https://en.wikipedia.org/wiki/Refraction)
• Reflection is the change in direction of a wavefront at an interface between two different media so that the wavefront returns into the medium from which it originated. (https://en.wikipedia.org/wiki/Reflection_(physics))
• It is defined as the bending of light around the corners of an obstacle or aperture into the region of geometrical shadow of the obstacle. (https://en.wikipedia.org/wiki/Diffraction)

So, by your "logic", a change in direction is the definition of refraction, reflection and diffraction. But of course, these are all different things, and so that definition is incomplete.

How often have I stressed using proper physics definitions when discussing physics.

Excellent answer Strange

[beecee]

On 10/8/2017 at 10:16 PM, Itoero said:

So a photon 'interacts' with particles in whatever medium it is and it always travels at c. Only the observable light can slow down and bend according to the medium . Correct?

When a photon moves through any medium, it is absorbed, re emitted, refracted and reflected, but always at "c" From our perspective it appears to slow, but actually just has a longer distance to travel. From the perspective of the photon though (if that were possible) time and distance to not exist and from its perspective, it will traverse the whole universe in an instant.

Edited November 8, 2017 by beecee

[Mordred]

yes but we know that the perspective of a photon frame of reference is an invalid reference frame and no such perspective is possible. I know this is what your referring to but wanted to make this clearer to other readers.

Massless particles follow null geodesics with ds^2=0 line elements (seperation distance) this is the detail that literally leads to the "null" portion under definition.

As stated I know your already familiar with this but the above could mislead discussion into "what is the viewpoint of a photon" discussion.

So I wanted to prevent that sidelight from occuring

Edited November 8, 2017 by Mordred

[beecee]

33 minutes ago, Mordred said:

yes but we know that the perspective of a photon frame of reference is an invalid reference frame and no such perspective is possible. I know this is what your referring to but wanted to make this clearer to other readers.

Massless particles follow null geodesics with ds^2=0 line elements (seperation distance) this is the detail that literally leads to the "null" portion under definition.

As stated I know your already familiar with this but the above could mislead discussion into "what is the viewpoint of a photon" discussion.

So I wanted to prevent that sidelight from occuring

No problems! Another thing with relation to light/photons, although having no rest mass, they do have momentum, and as such, are the reasons that light sails work, and a point that is not mentioned much, it also causes a very tiny infinitesimal amount of spacetime warpage.

[Itoero]

On ‎8‎-‎11‎-‎2017 at 5:07 PM, swansont said:

And refraction is not due to localized non-uniformities in the medium, it's due to the medium itself.

A high concentration of a certain kind of localized non-uniformities with a different refractive index forms refraction.

When light doesn't travel  through vacuum the photons interact with other particles which causes scattering. This is what Compton and Rayleigh scattering(there are other kind of scattering) are about....do you deny this?

 

[swansont]

Just now, Itoero said:

 When light doesn't travel  through vacuum the photons interact with other particles which causes scattering. This is what Compton and Rayleigh scattering(there are other kind of scattering) are about....do you deny this?

No, I am not denying that scattering is scattering. I am denying that refraction is scattering, and I have explained why several times.  When light travels further through a material, you get more scattering. The scattering takes place at a particular point along the path. We do not get blue light from Rayleigh scattering from one place in the sky. We get it from all of the sky.

Refraction does not behave like that. Do you deny this?

[studiot]

1 hour ago, swansont said:

No, I am not denying that scattering is scattering. I am denying that refraction is scattering, and I have explained why several times.  When light travels further through a material, you get more scattering. The scattering takes place at a particular point along the path. We do not get blue light from Rayleigh scattering from one place in the sky. We get it from all of the sky.

Refraction does not behave like that. Do you deny this?

Nice point. +1

[Strange]

2 hours ago, Itoero said:

When light doesn't travel  through vacuum the photons interact with other particles which causes scattering. This is what Compton and Rayleigh scattering(there are other kind of scattering) are about....do you deny this?

Please stop this ridiculous straw man argument. 

[Dubbelosix]

5 hours ago, swansont said:

No, I am not denying that scattering is scattering. I am denying that refraction is scattering, and I have explained why several times.  When light travels further through a material, you get more scattering. The scattering takes place at a particular point along the path. We do not get blue light from Rayleigh scattering from one place in the sky. We get it from all of the sky.

Refraction does not behave like that. Do you deny this?

measuring how scattering is linked to non-commutivity is the way. 

3 hours ago, Strange said:

Please stop this ridiculous straw man argument. 

Best not to answer questions you know are troll bait, act professional show no bias and skip the questions that hold no substance. This way, you defeat them, successfully. 

I just gave up on another site, just today, because two posters were clearly making stuff up as they went along, even though I gave precious hours out my time to entertain them . 

 

[Itoero]

On ‎8‎-‎11‎-‎2017 at 5:49 PM, swansont said:

That only works if the only way to change direction is scattering.We know e.g. that gravitational lensing and diffraction will change a photon's direction. Are they scattering? 

Yes, diffraction and gravitational lensing are due to scattering of the photons of light. Wave function collapse implies a wave can't change course or travel (unless in vacuum) without the interaction of its quanta with the particles of whatever medium it travels in.When quanta interact with particles they scatter.

[StringJunky]

28 minutes ago, Itoero said:

Yes, diffraction and gravitational lensing are due to scattering of the photons of light. Wave function collapse implies a wave can't change course or travel (unless in vacuum) without the interaction of its quanta with the particles of whatever medium it travels in.When quanta interact with particles they scatter.

You need to read some science books and realise definitions are not negotiable.

 

[Strange]

2 hours ago, Itoero said:

gravitational lensing are due to scattering of the photons of light.

Nonsense. You are just making up nonsense again. 

2 hours ago, Itoero said:

When quanta interact with particles they scatter.

Or reflect or refract or diffract. 

[Eise]

3 hours ago, Itoero said:

Yes, diffraction and gravitational lensing are due to scattering of the photons of light. Wave function collapse implies a wave can't change course or travel (unless in vacuum) without the interaction of its quanta with the particles of whatever medium it travels in.When quanta interact with particles they scatter.

Explain how gravitational lensing is scattering.

[Itoero]

2 hours ago, StringJunky said:

You need to read some science books and realise definitions are not negotiable.

 

This not just my opinion. Out of papers and discussions I find that the Wikipedia definition is correct. "Scattering is a general physical process where some forms of radiation, such as light, sound, or moving particles, are forced to deviate from a straight trajectory by one or more paths due to localized non-uniformities in the medium through which they pass."

Scattering is about wave and particle behavior. Diffraction, refraction and reflection deal only with waves.

 

[swansont]

3 hours ago, Itoero said:

Yes, diffraction and gravitational lensing are due to scattering of the photons of light. Wave function collapse implies a wave can't change course or travel (unless in vacuum) without the interaction of its quanta with the particles of whatever medium it travels in.When quanta interact with particles they scatter.

What particle is the photon scattering off of? What superposition is involved, requiring a wave function collapse?

Just now, Itoero said:

This not just my opinion. Out of papers and discussions I find that the Wikipedia definition is correct. "Scattering is a general physical process where some forms of radiation, such as light, sound, or moving particles, are forced to deviate from a straight trajectory by one or more paths due to localized non-uniformities in the medium through which they pass."

What is the localized non-uniformity causing gravitational lensing?

Just now, Itoero said:

Scattering is about wave and particle behavior. Diffraction, refraction and reflection deal only with waves.

If they only deal with waves, then how are they scattering? You contradict yourself here (not surprising, since you're wrong)

[Itoero]

12 minutes ago, Eise said:

Explain how gravitational lensing is scattering.

In such a lens, you have matter between light source and observer.  Light interact with the matter. Wave function collapse states the photons interact with particles of the matter...when photons interact with particles,  they scatter.

[swansont]

32 minutes ago, Itoero said:

In such a lens, you have matter between light source and observer.  Light interact with the matter. Wave function collapse states the photons interact with particles of the matter...when photons interact with particles,  they scatter.

The light isn't going anywhere near the matter.

[Eise]

21 hours ago, Itoero said:

In such a lens, you have matter between light source and observer.  Light interact with the matter. Wave function collapse states the photons interact with particles of the matter...when photons interact with particles,  they scatter.

Now you have shown very clearly to all of us that you are just making things up. I gave the pass, Swansont made the goal. The wave function of light can collapse when it interacts with matter. But nothing the like happens when light bends in a gravity field. It just follows its straight path, a geodesic, in spacetime.

I am wondering what you think about the state of your physics knowledge, sticking to your 'refraction is scattering' where several physicists here already told you x times that they are not the same. Especially when you start with such a question:

On 10/7/2017 at 4:46 PM, Itoero said:

I read the kinetic energy of a photon goes to infinity when a photon reaches c.

Every photon travels at c, and its energy is not infinite, but dependent on its frequency alone. Somebody missing such fundamental knowledge of physics tries to convince seasoned physicists that refraction is a form of scattering???

Edited November 12, 2017 by Eise