Giantkiller moves forward into Full Heterodyning.

[CTG Labs]

Thanks Omnispace!

So we know that photons leave the antenna, EM radiation.

So my question still stands?  Moving electrons cause magnetic fields, and the changing fields causes an electric field.

In space, near vacuum, no matter is present.  The photons travel through space.  How the magnetic and electric fields can exist in space?

There is no matter, in this case an electron to move and create a magnetic field.  Electric fields can only exist between two charged particles?  The photons have no charge.

Is then the photon then able to continually create the needed magnetic/electric fields in empty space with no other matter around?


Thanks,

Dave.

A common misunderstanding...even many EEs don't understand current and EM radiation.  First of all, understand that while current is a  measure of electron movement, the electrons are moving extremely slowly.  EM energy, on the other hand, moves at the speed of light.  The antenna radiates photons, which can be thought of as EM field disturbances.

You can make antennas which have high voltage and low current, or low voltage and high current.  You can still have a large power transfer by picking up the high voltage (E-field) at the receiver, then pumping a current through the receiving antenna.  The properly tuned antenna will perform the same function without the need for a current source.

omnispace

[Drossen]

The following is a quote from wikipedia at http://en.wikipedia.org/wiki/Photon:

In physics, the photon is the elementary particle responsible for electromagnetic phenomena. It is the carrier of electromagnetic radiation of all wavelengths, including gamma rays, X-rays, ultraviolet light, visible light, infrared light, microwaves, and radio waves. The photon differs from many other elementary particles, such as the electron and the quark, in that it has zero rest mass;[3] therefore, it travels (in a vacuum) at the speed of light, c. Like all quanta, the photon has both wave and particle properties (?wave?particle duality?).

I hope this helps answer your question CTG Labs.

Drossen

[sparks]

@CTG Labs

      You probably know what my answer is but you are definitely asking the right question.  The emwave in low mass fields has a very negligibe magnetic field associated with it.  You get the magnetic effect and I mean effect not force when charge and mass of one field are relative to charge and mass of another field.

       So to simplify my answer:  there is no magnetic field associated with the massless emwave in a hypothetical vacuum. It is not an electromagnetic wave and should be called an electrodynamic wave.

[EMdevices]

there is no magnetic field associated with the massless emwave in a hypothetical vacuum. It is not an electromagnetic wave and should be called an electrodynamic wave.

I'm not sure why I'm letting myself get pulled into this, but the above statement is not correct. there is a magnetic field.

If you guys want to understand EM waves there's plenty resources on the internet.  E fields are not generated only by charges, but by time changing magnetic fields as well.   One form has a finite divergence the other does not (forms loops).    so once the waves are radiated off of an antenna,  the magnetic field induces the electric field and in turn the electric field induces the magnetic field, and so they keep each other going and propagating out in space.

EM   

[CTG Labs]

GAH!!!!!!!!!!!!!!

@Drossen, thank you for you reply, I am aware of the information you provided.  I by no means consider myself an expert, but you apparently are but do not seem to actually "see" my question!  (no offence intended)

@Sparks, thank you, some who seems to understand my question!  Your info starts to explain things better than my books!

@EMDevices!  "so once the waves are radiated off of an antenna,  the magnetic field induces the electric field and in turn the electric field induces the magnetic field, and so they keep each other going and propagating out in space."  YES! BUT! How can the magnetic field or an electric field exist in space?  Can I ask you to place yourself outside the earths atmosphere and ask how a magnetic field can exist in space to create an electric field and how an electric field can exist in space when there are no charged particles of matter?

A photon (as are all particles) are waves and particles depending on measurement/observation point.  So the photon IS the wave OR the photon creates the magnetic field?  HOW the magnetic field can exist in empty space?

Or we need to start considering the quantum vacuum to explain how this wave propogates.

Need I say that the Aether was "invented from thin air" to explain how these waves can exist in a space devoid of mass?!  The mathmatical theories that we use today were written assuming this?  Then the Aether was disproven (static aether anyway) by M & M over 100 years ago, but the theory of the waves remains the same?!

I am sorry to go on guys, perhaps I am just thick and should keep my comments to myself?


Thanks to all.


Dave.