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Nature of light


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So radio waves vibrate sideways (at right angles to their direction of travel).

 

Any idea how they do that? Well, yes, you have pages of mathematics on that subject. I mean, anything that will educate ME?

 

 

This "vibration" is the strength of the electric and magnetic fields. It is not a physical displacement as with a rope. You might note that on the diagrams you see, if they are any good, the axes will be labeled. Each transverse direction is amplitude of the field.

 

such as

http://hyperphysics.phy-astr.gsu.edu/hbase/Waves/emwavecon.html

 

That one I like because it doesn't even show a continuous curve, which is often misleading to neophytes, who then think the wave actually travels a sinusoidal path.

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So the electric field and the magnetic field go perpendicular of each other, and of the direction of travel.

 

(Back to the rope analogy! The wave travels perpendicular to the actual movement of the rope. "Wow! Who'da thunk it?!")

 

Back in the Dark Ages, we used to make electrons slosh back and forth in a resonant circuit. This generated a wave that went out of the antenna in all directions. But as far as I know, the electrons in the resonant circuit didn't go out of the antenna and into space.

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So the electric field and the magnetic field go perpendicular of each other, and of the direction of travel.

 

(Back to the rope analogy! The wave travels perpendicular to the actual movement of the rope. "Wow! Who'da thunk it?!")

 

Back in the Dark Ages, we used to make electrons slosh back and forth in a resonant circuit. This generated a wave that went out of the antenna in all directions. But as far as I know, the electrons in the resonant circuit didn't go out of the antenna and into space.

Why would they?

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The Electric Company does not sell us electrons.

 

It uses its big machines to make our own electrons slosh back and forth in our own house wiring at sixty cycles.

 

We pay them to do this for us.

 

Then we did various things with this energy and made our own privately-owned electrons slosh back and forth in resonant circuits.

 

Since we couldn't see what was happening, we thought all sorts of things about what was making the connection between our transmitters and other people's receivers. I, for one, was surprised to find that my own collection of electrons stayed right in the final circuit and did NOT go out "thru the Aether" to the world.

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Since we couldn't see what was happening, we thought all sorts of things about what was making the connection between our transmitters and other people's receivers. I, for one, was surprised to find that my own collection of electrons stayed right in the final circuit and did NOT go out "thru the Aether" to the world.

Great, you learned some physics. Not sure what this has to do with the nature of light, unless your point is that light is not made up of electrons, which I thought was already pretty well established.

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Mordred,

 

Educate me here: Is a flow of electrons different from a flow of charge? How?

 

If I wave a magnet over a coil and it motivates a bunch of electrons to move back and forth, say an inch, and that causes electrons a mile or two up the line to move back and forth, is that not charge moving?

 

Glenn

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Does vibration cause the atoms to flow in a material ?

 

In flow of charge the charge is mediated by photons. The photon in essence transfers the charge from one electron to another via orientation change. By photons I am specifically referring to the vector gauge virtual photon. Which can exhibit one or more quantum properties.

 

The proton, electrons and photon are charge carriers. For example in a circuit you have two simultaneous charge flows. Positive to negative and vise versa. You you have a flow of positive charge and a flow of negative charge. Which equates to the magnetic moment (spin) orientation density at a particular location. Ie a higher percentage will have a given orientation.

 

Lol little side note if positive charge meant flow of protons then the individual elements would temporarily change which is obviously flat out wrong. Here is a fairly decent classical coverage.

 

http://web.mit.edu/8.02t/www/802TEAL3D/visualizations/guidedtour/Tour.htm#_Toc27302307

 

Another clue that it is charge that flows and not the protons and electrons is the medium. No two particles of different mass can flow through a medium at identical rates. Hence a single particle must be mediating the charge. ( the rate of charge flow tells us this particle must be massless) hence the photon vector guage boson.

Edited by Mordred
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I have put silver wires into distilled water (with a little salt) and applied 28 volts of direct current. In a matter of hours, the water takes on a golden color and the silver metal takes on a corroded, abraded look.

 

My conclusion is that actual silver atoms are being moved from the solid metal into the water.

 

Heavier evidence: Every day flatbed trucks haul big slabs of impure copper from the smelter to someplace east of here.

They are electroplated from those slabs to new ones of pure copper. The impurities fall into the bottom of the tank.

 

Gentlemen, electrons may not move, but copper atoms do.

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As we all know a charged particle has an electromagnetic field that propagates away from it at the speed of light. If we move/accelerate that charged particle it's field starts propagating away from it's new location in space. Could we say that the difference between it's old position and new position is a photon that displays exactly the energy required to make that move?

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As we all know a charged particle has an electromagnetic field that propagates away from it at the speed of light. If we move/accelerate that charged particle it's field starts propagating away from it's new location in space. Could we say that the difference between it's old position and new position is a photon that displays exactly the energy required to make that move?

 

No.

 

In the first place the radiation of an EM filed is a classic wave effect, and only occurs when the charge is accelerating.

In the second place the emission of a photon is a quantum effect and in this case there is no emission dues to acceleration.

For instance the electron does not spiral into the nucleus, loosing energy by emitting photons.

 

The emission of EM waves is typified by the X rays emitted by a cathode ray stream, accelerated in a vacuum tube.

The re is obviously a relationship between the X rays and the elctron stream, but it is not quantised.

 

Here is a nice gif of the emission of EM by a moving charge, courtesy NASA.

 

post-74263-0-15654000-1497031562.gif

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As we all know a charged particle has an electromagnetic field that propagates away from it at the speed of light. If we move/accelerate that charged particle it's field starts propagating away from it's new location in space. Could we say that the difference between it's old position and new position is a photon that displays exactly the energy required to make that move?

You only get photons from accelerating the charge. It doesn't require additional energy to maintain linear motion.

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It is Impossible to move an object without acceleration and if it was accelerated it emits photons and all objects are made of charged particles. Come on guys or gals, it was a serious question that deserves some thought. Why is it that every time someone asks a question that isn't in a text book we treat them like their an idiot?

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It is Impossible to move an object without acceleration and if it was accelerated it emits photons and all objects are made of charged particles. Come on guys or gals, it was a serious question that deserves some thought. Why is it that every time someone asks a question that isn't in a text book we treat them like their an idiot?

 

 

You seem to have received some serious answers. Can you say exactly what you think is unsatisfactory about them; then perhaps people can explain further.

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What is really going on when we accelerate a charged particle? A charged particle has an electromagnetic field that is always propagating away from it at c so when we accelerate it that field must start propagating away from it in a new position in space. The difference in those two positions could be construed as a photon. Something like the perpendicular part of a square wave with the angle of the perpendicular part being determined by how much acceleration is used to accelerate the charged particle. That angle being the wavelength.

Edited by Bird11dog
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It is Impossible to move an object without acceleration and if it was accelerated it emits photons and all objects are made of charged particles. Come on guys or gals, it was a serious question that deserves some thought. Why is it that every time someone asks a question that isn't in a text book we treat them like their an idiot?

 

 

You can be in motion relative to me, without you having undergone an acceleration. Even if you are the one accelerated, and have a net charge, you will not radiate once you are in uniform linear motion.

What is really going on when we accelerate a charged particle? A charged particle has an electromagnetic field that is always propagating away from it at c so when we accelerate it that field must start propagating away from it in a new position in space. The difference in those two positions could be construed as a photon. Something like the perpendicular part of a square wave with the angle of the perpendicular part being determined by how much acceleration is used to accelerate the charged particle. That angle being the wavelength.

 

You can derive all of this. Jackson's book on Electrodynamics is a standard place to learn it, although Griffiths might also cover it.

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You can be in motion relative to me, without you having undergone an acceleration. Even if you are the one accelerated, and have a net charge, you will not radiate once you are in uniform linear motion.

I'm not sure that I wouldn't radiate. The radiation would have wavelengths so long they would be undetectable..

Jackson's is what made me think about it.and his drawing of an accelerated charged particle.

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I'm not sure that I wouldn't radiate. The radiation would have wavelengths so long they would be undetectable..

Jackson's is what made me think about it.and his drawing of an accelerated charged particle.

 

 

In your frame you would be at rest. You can't radiate in one frame and not in another.

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