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Is it correct that the varying stream of electrons or photons or wavicles etc. in the transmitting antenna (i.e complex analog signal) are literally flying or traveling in air or vacuum and then get inside the receiving antenna to form back the transmitted information?

If not, then what is the best explanation how does the information reach at the receiving end?

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  • $\begingroup$ Welcome, but the site expects some physics background from the questioners here. have a look at a simple explanation to your question here explainthatstuff.com/antennas.html $\endgroup$
    – anna v
    Apr 14, 2017 at 3:36
  • $\begingroup$ If you want to learn something read in PSE about physics.stackexchange.com/… and you will go deeper and deeper into details. Good luck. $\endgroup$ Apr 14, 2017 at 7:25
  • $\begingroup$ I need to know the answer that touches the realistic events behind that graphical representation. Example: we always show an electromagnetic wave in sinusoidal form, but what really happens behind that electromagnetic wave? In realistic event. Does it represent the motion or variation of amount of particles in the air? or it is just a radiated energy of photon from the transmitter antenna that varies periodically? We need to know the depth reality behind it aside from complex mathematical equations. It is better to explain it in non mathematical manner $\endgroup$
    – Pisiko
    Apr 14, 2017 at 7:38
  • $\begingroup$ @anna v . I am questioning the deepest reality behind such stuff. If you really deeply understand a certain phenomenon. Then, you can answer without excuses. As Einstein says, "if you cannot explain it simply, you don't understand it well." That means even if your audience is a kid, if you've deep understanding to that, you can explain it in a way a pupil can understand. With that, I can say, Einstein is correct again. $\endgroup$
    – Pisiko
    Apr 16, 2017 at 2:57
  • $\begingroup$ Einstein is not the Pope of physics. He did not believe in quantum mechanics either ( which main stream physics considers the underlying level of reality). And probably when he said "simple" he meant with approximate equations. There are open courses in MIT ocw.mit.edu/courses/find-by-topic/#cat=mathematics also for physics $\endgroup$
    – anna v
    Apr 16, 2017 at 8:22

2 Answers 2

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The only accessible reality to physics studies is the one we can reach with our mathematical tools. They extend our five senses to small and large dimensions and describe what our instruments measure. This site is for mainstream physics questions and mathematics is the basic language.

When physics mathematical knowledge is used in engineering, which is the realm of antennas and transmission of information, another site would be appropriate for submitting this question, because the complexity becomes even worse.

A simplistic explanation of how information can be transmitted with radio frequency electromagnetic waves is the following:

Electromagnetic waves ride on zillions of elementary particles, called photons. Have you seen a stadium wave ? Its medium is people lifting themselves off their seat in a time sequence, nobody moves much, but the wave passes . If the thousands of people were throwing a ball in the direction of the wave, there would be a wave of balls going around the stadium.

Electrons in the metal of the antenna, under the rhythmic influence of induced currents in the antenna metal, throw off, radiate, photons that join up, and, with the velocity of light, leave the antenna as a coherent wave. This wave reaches a receiver antenna which interacts with the electrons in the antenna, and gives them a drift velocity with the frequencies and intensity of the incoming wave, which generates a current, which can be read in the electronic instruments of the antenna.

The modulation of the currents in the transmitting antenna can imprint a signal on these zillions of photons ( either in intensity or in frequency) which is transmitted to the receiving antenna.

The Morse code was the first way that information was modulated on an electromagnetic wireless signal,

Starting in late 1894, Guglielmo Marconi began pursuing the idea of building a wireless telegraphy system based on Hertzian waves (radio). Marconi gained a patent on the system in 1896 and developed it into a commercial communication system over the next few years.

At present electronic circuits can continuously modulate radio wave beams, carrying complicated sounds and images which leave, riding on zillions of photons through the air, and are received in a receiving antenna, the signal read off the currents induced by the absorption of the incoming photons.

To get an idea of what complicated mathematics models electromagnetic waves need have a look at this

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  • $\begingroup$ I appreciate your answer. This is what I mean how to answer my question. Not having too much mathematical jargon. I know mathematics is a tool. But according to Einstein, if you explain it simply undressed with mathematical equations , that imply a mastery of the subject matter. $\endgroup$
    – Pisiko
    Apr 16, 2017 at 5:06
  • $\begingroup$ By the way, about Morse code and history of it is not needed to my question but thank you for such extension. $\endgroup$
    – Pisiko
    Apr 16, 2017 at 5:08
  • $\begingroup$ Electromagnetic wave riding on zillions of particles (photons)? but Fields are forces right? So, does it mean forces are riding on zillions of photons? Does it necessary for the force to ride on photons? Or force comprised of particles? Common , I need deep thinking to this. $\endgroup$
    – Pisiko
    Apr 16, 2017 at 5:14
  • $\begingroup$ Deep thinking that is undressed of mathematical equations. I believe philosophical thinking is the reason why mathematical equations exist. $\endgroup$
    – Pisiko
    Apr 16, 2017 at 5:16
  • $\begingroup$ If your last is true, ancient greeks would have invented quantum mechanics. They really thought deeply. It was the mathematical tools developed for physics by Newton and others that unlocked the science of physics from verbiage. $\endgroup$
    – anna v
    Apr 16, 2017 at 5:39
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Basic phenomenons of the electromagnetic radiation

  1. EM radiation happens through the emission of photons from excited subatomic particles.
  2. The excitation of subatomic particles happens through the absorption of photons (1. and 2. are not the full picture, see below).
  3. Photons are indivisible quanta of the EM radiation.
  4. Powerful excitations of subatomic particles led to powerful EM radiation in the range of X-rays emission and Gamma ray emission, soft excitations to infrared emission. The visible light is between (and we call it between because we are adopted to it during our evolution).

Applications of EM radiation by humans (according to your question)

  1. Accelerated between a gap in the conducting circuit electrons produce EM radiation in a wide range from visible radiation (sparks) to X-rays. See the Spark Gap transmitter of Heinrich Herzt.

  2. Moving non-parallel to an external magnetic field electrons undergo a deflection perpendicular to the plane between the direction of movement and the external magnetic field. Take the thumb and the second and third fingers of your hand to visualize this! It's called the Lorentz force. During the deflection the electron looses kinetic energy (gets de-accelerated) and emits EM radiation (and came to standstill after exhausting its kinetic energy in the form of the emitted radiation).

Radio waves

In an antenna rod - which the s an open electric circuit - electrons get accelerated and de-accelerated forth and back by an antenna generator (AC current):

enter image description here

With curtesy to Wikipedia, the animation see here

The synchronously and periodical accelerations of the electrons led to a synchronously and periodical emission of photons.

In the near field of the antenna - moving with the radiation (with the speedd of light) in the direction of radiation (line of observation perpendicular to the antenna rod) - the radio wave looks like the graphics in this explanation of the photons electric and magnetic field components.


Your right thoughts

Is it correct that the varying stream of electrons ... in the transmitting antenna ... (induce photons which)... are literally flying or traveling in air or vacuum and then get inside the receiving antenna to form back the transmitted information?

  • Yes, an accelerated stream of electrons induces a stream of photons, flying in empty space away until hitting subatomic particles (the receiving antenna.

  • Making a modulation to the emitted EM radiation one could transmit information. In the easiest way interrupting the radiation (Morse signal mentioned by Anna) or varying the frequency of the radio wave or varying the intensity of the radiation.

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  • $\begingroup$ I assume that you as a native speaker eradicate my mistakes. Thanks in advance. $\endgroup$ Apr 16, 2017 at 7:21
  • $\begingroup$ You mean YES for photons that travels not the electrons? Electrons are just in the antenna, but the radiated photons are the ones that travel? Is that what you mean , right? $\endgroup$
    – Pisiko
    Apr 16, 2017 at 8:17
  • $\begingroup$ Actually, I was just waiting for those who can explain or oppose that thought of mine. That kind of question is actually inciting to oppose or favor such idea. It is not good that if you don't like that question then you vote it as out of topic or what instead of countering it intellectually which is more productive than not answering it. Intellectual discussion without discrimination as long as it is proper and within limit of main subject (Physics) why don't we try to correct such idea or such question and answer it accordingly? Am I not right? $\endgroup$
    – Pisiko
    Apr 16, 2017 at 8:23
  • $\begingroup$ Why not saying like this, "that is not the correct question or idea, this is the correct questioning and this is the correct answer, and/or check this link " $\endgroup$
    – Pisiko
    Apr 16, 2017 at 8:28
  • $\begingroup$ Your answer really helped. Thank you very much of your answer. I appreciate it much. $\endgroup$
    – Pisiko
    Apr 16, 2017 at 8:29

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