Photon Creation

[Little Bang]

This thread supplies the why, how, and where of radiation propagation. It is astounding to me that some refuse to see the implications of it. They refuse to see that the virtual particle is dead because to do so requires the standard model to go in the garbage. Einstein proved that matter and energy can be changed from one to the other and yet we still search for some basic particles to explain the Universe. The Universe is made out energy, deal with it.

[Erasmus00]

This thread supplies the why, how, and where of radiation propagation.

 

Your thread is an exact restatement of classical radiation, as has been pointed out. There are experimental reasons that science has moved beyond classical electricity/magnetism- in particular the classical model cannot explain the fact that photons carry an energy proportional to frequency (i.e. [imath] E= \hbar \omega [/imath]). Nor can it account for the angular momentum in the field being a multiple of [imath]\hbar[/imath].

 

Einstein proved that matter and energy can be changed from one to the other and yet we still search for some basic particles to explain the Universe. The Universe is made out energy, deal with it.

 

What do you mean by energy? I think too often we use the word energy without stopping to think about what we mean- energy is an abstract mathematical concept that happens to be conserved, it isn't as concrete as the usage would make you think.

[Little Bang]

Particle accelerator physics - Google Books

[Pyrotex]

...What do you mean by energy? I think too often we use the word energy without stopping to think about what we mean- energy is an abstract mathematical concept that happens to be conserved, it isn't as concrete as the usage would make you think.

This is very important. And so few understand it.

 

Matter is "stuff". Matter consists of particles having mass. Particles are "things".

 

So good so far. But Energy is not "stuff" and it is not "things" or "a thing".

 

A particle can carry energy. We calculate that by E = 1/2 M V^2

One half mass times velocity squared.

 

But where is the "energy"? The particle has only mass and velocity, that's all.

 

The energy is an abstract mathematical concept, but we can calculate it with exquisite precision. E = 1/2 M V^2

 

Consider a brick on top of the Eiffel Tower. It has potential energy. E = M G h

Mass times height above "ground".

 

But where is the "energy"? The brick has only mass and position in a gravitational field.

 

BUT NOTICE: Ignoring air resistance, if we knock the brick off the Eiffel Tower and it falls, and we calculate its Total Energy at every point in its fall, an amazing thing is seen: the Total Energy is a constant!!!

 

Total Energy = 1/2 M V^2 + M G h

 

where V is the velocity at that point in time, and h is the height at that point in time.

 

Total Energy does not change!! Energy is conserved!!

 

But WHAT is the energy??????? :beer:

 

Energy is not a WHAT or a WHERE. It is a passing relationship, a dynamic concept.

[Little Bang]

No disagreement on any of your points but in the final analysis isn't the fundamental form of energy a wave since any particle can be converted into a wave?

[Little Bang]

No disagreement on any of your points but in the final analysis isn't the fundamental form of energy a wave since any particle can be converted into a wave?

 

Will a charged particle accelerated at 10^10g radiate? Yes. At 10^5g? Yes. At one g? Yes. How about 10^-10^-10g? The answer also must be yes. My point, a charged particle in motion WRT an observer must also radiate, albeit the wavelengths will be very long.

[Qfwfq]

...albeit the wavelengths will be very long.

Yes, infinitely long.

 

Which implies frequency being infinitely low because the period will be infinitely long. This of course is possible only if the motion is constant for an infinitely long time. But, of course, if it isn't then there has been or will be an acceleration, right?

Edited August 23, 2010 by Qfwfq
dumb mistake!

[Little Bang]

Another interesting thought. If the charged particle is perfectly stationary WRT an observer there is no way for the observer to know the particle exists?

 

BTW eras, my last course in physics was 306, electricity & magnetism 1962.