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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?

Qmechanic
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Pisiko
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  • Welcome, but the site expects some physics background from the questioners here. have a look at a simple explanation to your question here http://www.explainthatstuff.com/antennas.html – anna v Apr 14 '17 at 03:36
  • If you want to learn something read in PSE about https://physics.stackexchange.com/search?q=Photon+electromagnetic+radiation+radio&tab=newest and you will go deeper and deeper into details. Good luck. – HolgerFiedler Apr 14 '17 at 07:25
  • 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 – Pisiko Apr 14 '17 at 07:38
  • @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. – Pisiko Apr 16 '17 at 02:57
  • 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 https://ocw.mit.edu/courses/find-by-topic/#cat=mathematics also for physics – anna v Apr 16 '17 at 08:22
  • I believe Einstein did not say it wholly literally. I think when he said simple, it means explaining the complicated or layered things in a way that cumbersome mathematical equations or expressions are minimized or avoided. – Pisiko Apr 16 '17 at 08:41
  • Let's take this simple Example. A simple equation of V= I x R , instead of saying that way "Ve equals Ay times Ar", you can explain like this to a medical doctor that V represent the force that pushes the electrons in the conductor to move, where I represent the stream of electrons, and R is the characteristic of material that resist the motion of electrons . This is just an example how to explain where mathematical equations are minimized. – Pisiko Apr 16 '17 at 08:48
  • What is a Force? Force is F =m.a . Instead of simply saying force is the product of mass and acceleration. Go down deeply to the very cause of the existence of force like this: Force exists because of the existence of mass of an object and its motion. Mass of an object exists because of the existence of gravity. This gravity makes the object to resist as it moves. So, the root cause of the existence of Force is gravity. This is what I mean deep thinking explanation in the absence or minimal presence of mathematical expressions. – Pisiko Apr 16 '17 at 09:25
  • Then, what cause the gravity to exist? graviton? how can we mathematically formulate the gravity in terms of graviton? Then, what makes the graviton to exist? we will go down deeper and deeper, and I believe the existence of everything is infinite. It is infinite in both arrows of small and big things. There must exist smallest of infinite smallest and biggest of infinite biggest. This is what I hold belief , so far , I never decline except if proven otherwise. – Pisiko Apr 16 '17 at 09:33

2 Answers2

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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

anna v
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  • 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. – Pisiko Apr 16 '17 at 05:06
  • By the way, about Morse code and history of it is not needed to my question but thank you for such extension. – Pisiko Apr 16 '17 at 05:08
  • 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. – Pisiko Apr 16 '17 at 05:14
  • Deep thinking that is undressed of mathematical equations. I believe philosophical thinking is the reason why mathematical equations exist. – Pisiko Apr 16 '17 at 05:16
  • 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. – anna v Apr 16 '17 at 05:39
  • Fields are not forces. Fields are real number representations of what a test particle would feel as force at that (x,y,z) . The photons themselves as quantum mechanical particles have a wavefunction that contains the E an B of the emergent classical field. The wave functions in superposition create the classical wave, and it is what the mathematics shows in the last link in my answer. – anna v Apr 16 '17 at 05:41
  • Field are not forces? So, why its unit of measure is Newton per coulomb or Volts per meter? If something is defined with its units, that something is meant by that unit. So, how come it couldn't be like that for field? Help me understand this. Thank you. – Pisiko Apr 16 '17 at 05:54
  • If we have a field of 1 Newton for 1 Coulomb , that means 6.24x10^18 electrons produce a force of 1 Newton, right? So how come the field cannot be interpreted as force caused by electrons? – Pisiko Apr 16 '17 at 05:59
  • If it were a force, it would be in newtons. To become a force you have to multiply with coulomb, which is what I stated ( without units) . Charges are measured in Coulombs. The units are so that the fomulae make sense and are consistent. – anna v Apr 16 '17 at 08:04
  • Yeah, all in all , it is a force. It is clear that each charged electron produces a force (Newton per Coulomb), and since there are a total of C charges , so the result is N/C x C or Newton. – Pisiko Apr 16 '17 at 09:46
  • It is mathematics of a force. The field itself is a mathematical concept and can only be seen when a real charge interacts with it. see this https://physics.stackexchange.com/questions/326049/what-is-actually-a-field-in-physics-how-can-something-affect-something-at-a-d/326054#326054 – anna v Apr 16 '17 at 10:22
  • Yes it's mathematics of force. My interpretation to that is similar to this: velocity = displacement / time , this means that velocity refers to the distance it takes for a moving object per unit of time. Similarly, E-field = force / charge, this means the amount of force per unit charge. Or, i.e, the force of each electron. If each electron force (E-field) times the total member of the group (coulomb) yields the total combined force of the group , Newton. Correct me if this interpretation is flawed. Anyway, thank you very much for your clarification. – Pisiko Apr 16 '17 at 12:14
  • displacement you can measure with a meter stick and the time with a clock. Force you can measure, but the field not, except circularly, because you see a force. – anna v Apr 16 '17 at 13:06
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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.

HolgerFiedler
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  • I assume that you as a native speaker eradicate my mistakes. Thanks in advance. – HolgerFiedler Apr 16 '17 at 07:21
  • 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? – Pisiko Apr 16 '17 at 08:17
  • 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? – Pisiko Apr 16 '17 at 08:23
  • 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 " – Pisiko Apr 16 '17 at 08:28
  • Your answer really helped. Thank you very much of your answer. I appreciate it much. – Pisiko Apr 16 '17 at 08:29
  • @Pisiko I've change the text a little bit because you are right of that I missed to show the step about photon emission. – HolgerFiedler Apr 16 '17 at 11:25
  • @Pisiko Having a long breath and being polite you can learn a lot on this PSE. AND you have to follow the rules and boundaries of mainstream physics which is the guarantee for the very high level of PSE. (If you get downvote than not from me. From me you got +1. And today an answer.) ;-) – HolgerFiedler Apr 16 '17 at 11:29