What IS a radio wave? What is it MADE out of? I saw an analogy

Electromagnetic radiation.

>>8966302
>What IS a radio wave?
We dont know.

It's like gravity. Newton figured out how to calculate its strength, but stated that he didnt know its physical cause /explanation. The same type of thing happens with electromagnetism, we just dont know what its all about physically.

>>8966306
But what IS electromagnetic radiation? (Also, is all radiation electromagnetic?)

Also, how do these waves move through vacuums? Are they moving through matter that's so small we haven't discovered it yet?

>>8966340
it's just photons man. the reason the double slit experiment is so interesting is that photons can both be observed and also propagate as a wave not bounded to a particle. at certain frequencies it can propagate through walls or not even pass through clothing (low freq/high freq, relatively).

>>8966340
There are several kinds of radiation. EM waves travel through the EM field which is constantly present at all points in the universe

>>8966348
So... It's like a wave of photons? Are photons the particles that are produced when electrons change valence level quickly? Where do they come from, are they part of the electron somehow or ???

Also, if computers store information as a bunch of on-and-off switches (for example), how is information stored in a radio wave?

>>8966351
Is the EM field one of those things that we just don't understand the cause of? Like gravity and proton-electron attraction?

>>8966348
to add to this, a force applied to an object from a single point (a single particle) spreads that force via photons (think of photons as communicators of energy) to nearby particles at the speed of sound, so a miles-long stick on one end wouldn't move for some time if you waved the other end. the reason a piece of paper is floppy is due to inertia, but very slightly also because energy propagates between particles at the speed of sound.

photons deliver the energy of all forms of radiation- heat, electricity, magnetism, etc all move as photons, and all photons are waves and particles simultaneously. the waves are simply a different frequency and amplitude from one another. that's why you can protect yourself from harmful radiation like UV with sunscreen and clothing, and protect yourself from xrays from nuclear radiation with dense materials like lead. both xrays and ultraviolet rays, along with radio waves, visible light, gamma rays, etc are all photons, just photons moving at different frequencies and amplitudes. this is high school physics lol.

>>8966390
FM radio means frequency modulation radio. radio receivers can take what is effectively an 'imperfect' radio wave from a radio station, decode it, and play it as music, which is why you can't hear rock music right now playing from a radio tower (but you can when you turn on the radio receiver). a simple low frequency wave like 98.7 megahertz does not itself send music to the radio receiver. 98.7 is a channel of sorts, and has bandwidth (for radio stations the bandwidth is usually .2 megahertz, which is why your car radio only moves on odd decimals [98.1, 98.3, 98.5, etc]). The radio station modulates the music, amplifies it through use of a radio tower, then your receiver receives it, 'unmodulates' it, then plays it. This is the same effect for cell phone calls, which is why you can't hear people talking on the phone right now but can get calls. Text messages also operate on a specific frequency range. The calls and texts have different modulations I think, if you really want to look into it I think my post has all the basics for you to begin researching with.

>>8966390
an electric field is a property of the universe, in much the same way a property of matter is its density or electron configuration. Another way to think about this is you wouldn't ask why causes hydrogen to be hydrogen, it's hydrogen because of properties of the universe.

>>8966340

the reason light travels through a vacuum is because it has two sine waves that propagate eachother.

I don't know about maxwell's equations or anything but its probably something similar.

>>8966434
Yeah a magnetic wave and an electrical wave will do that, and they have a little baby photon

>>8966409
But I thought waves could go thru walls and shit. They can be blocked by certain materials?

Also, why does having different frequencies keep waves from affecting one another? What if the photons happen to collide?

>>8966434
What does it mean to say that the waves "propagate eachother"?

>>8966302
>What IS a radio wave?
Vibrations in a field.
>What is it MADE out of?
That's like asking what time is made out of.
>But with radio waves, what is the water drop and what is the "up and down" motion?
there isn't an "up and down" motion
It's a 3 dimensional wave and humans can't describe it well because that's just not how humans evolved to perceive the universe.
So think less "waves on the surface of the ocean" and "currents throughout the ocean itself"
>>8966340
>Also, how do these waves move through vacuums?
Vacuums aren't real. What you think is a "Vacuum" is just a low energy location in a given field. And we know how energy likes to diffuse and create equal energy levels, similar to how heat works.

>>8967376
With an electromagnetic wave you have two transverse "vibrations or fluctions, the Electric field (which accelerates charges) and the Magnetic field. The laws of electrodynamics (Maxwell's equations) state that a changing Electric field with respect to time generates a Magnetic field, and a changing Magnetic field with respect to time generates an Electric field. Two transverse sine waves of the E and B field just happen to be solutions to the special case where there is no matter or charge (the vacuum). We don't know what makes up the E field and B field as far as I know; it just is.

>>8966340
Light propagates through the aether.

photons

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>>8966302
the notion of field is the most retarded idea dumped by rationalists, it's pure cancer

>>8967472
>The autist enters the stage from the left

>>8967388
So waves are just a concept and arent physical? What are we measuring then?

>>8967518
Waves are a description of the transformations of a particle field values changing over time.
>What are we measuring then?
Energy level at a given location at a point in time.

>>8967392
Thanks for the response, this makes more sense now

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>>8966302

Waves don't have to be "made out of" anything. All they need is the "up and down", a wave is any pattern that propagates through space.

In classical physics, a radio wave is an oscillation in the electric and magnetic fields traveling through space. It propagates because a changing electric field causes magnetic fields and vice versa.

In quantum mechanics, a radio wave is what we observe when a large number of low-frequency photons are emitted in sync.

>>8966302
>>8966340
You can literally ask the "what is X" question an infinite number of times. Unless you have context of the "what is", the answer will mean jack fucking shit to you. Basically replacing one unknown with another unknown.

so much anti-intellectualism itt
>that's meaningless
>we can't know that
>we can't conceive that
>don't ask that
neo-positivists can't bear the thought that there are foundational conceptual questions about their favorite fields, so they get angry when confronted with them

>>8967539
>Waves are a description of the transformations of a particle field values changing over time.
so when a radio wave hits an antenna, the antenna is being hit by a description
k.

>>8967388
>Waves don't have to be "made out of" anything. All they need is the "up and down", a wave is any pattern that propagates through space.
but the idea of a self-existent "pattern" is gibberish
it's like saying an ocean wave could exist without any water
a pattern is a pattern of something; if it doesn't consist of anything then how can it be anything at all?
>a radio wave is an oscillation in the electric and magnetic fields traveling through space
in this case the wave would presumably be made out of whatever an electromagnetic field is made out of
>a radio wave is what we observe when a large number of low-frequency photons are emitted in sync
in this case is the observation illusory or not? is a wave actually formed not? if it is, the wave would presumably consist of those photons

>>8967388
>>What IS a radio wave?
>Vibrations in a field.
>>What is it MADE out of?
>That's like asking what time is made out of.
these answers are incompatible
if the wave is a vibration in a field, then obviously it consists of whatever the field consists of, like an ocean wave consists of the water of the ocean
if you then want to deny that the field consists of anything, how are you not talking nonsense?

>>8966409
>all photons are waves and particles simultaneously
but waves and particles have incompatible properties, so this is a paradox
actually believing that it's the truth (instead of, say, that photons are something that seems both like waves and particles) is embracing some kind of mysticism

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>>8966302
An Electromagnetic Waves are just electrons being propegated by an antenna. THey are literally just electrons. The oscillations are caused by, what i assume is Alternating Voltage in a form of a sine wave. Then that voltage is propegated by an antenna in a form of vertical electric waves and horizontal magnetic waves.These waves are considered light, so in a vaccum or nature they travel in the speed of light. The higher the frequency the more LOS(line of sight) transmission is required. A UHF frequency is used when you can see the entity desired and does not usually do well through walls,, hence why you want your wifi signal sucks through as more walls are in the way.
>>8968422
>so when a radio wave hits an antenna, the antenna is being hit by a description
k.
In terms of radio communication when receiving a transmission the wave is a mixture of a carrier wave(which is pre set) and an intelligence wave(actual speaking). The radio Receiver/Transmitter then decodes this, speparates the carrier wave through some electrical filters, then all thats left is the intelligence wave or theacutally speaking.
> >Waves don't have to be "made out of" anything. All they need is the "up and down", a wave is any pattern that propagates through space.
but the idea of a self-existent "pattern" is gibberish
it's like saying an ocean wave could exist without any water
a pattern is a pattern of something; if it doesn't consist of anything then how can it be anything at all?
It's in the name, Electromagnetic wave. It's made up of Light and can be explained as made up of the energy of electrons.
> >all photons are waves and particles simultaneously
but waves and particles have incompatible properties, so this is a paradox
actually believing that it's the truth (instead of, say, that photons are something that seems both like waves and particles) is embracing some kind of mysticism
This is the more interesting part if physics. They are different, but can be represented as both.

>>8966326
>""'scientists""" still can't find the origin of basic truths about the universe
>condemn religion

>>8968523
Electrons have mass and don't travel at c, ya dingus.

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>>8968523
>An Electromagnetic Waves are just electrons being propegated by an antenna

>>8968344
this guy, just listen to this guy, this guy got it, rest of you please stop posting weird things

>>8968344
>Waves don't have to be "made out of" anything. All they need is the "up and down"
So in this case, it's not a physical back-and-forth movement, it's the energy levels of particles (electrons?) increasing then decreasing back and forth?

Kind of off-topic, but I just read about USB's and LSB's. I messed around with an online radio and you can see that the incoming radio waves aren't just 1 frequency, they seem to each be a small range of frequencies. (USB is above the frequency you're tuned to and LSB is the one below.) Do antennae transmit/receive multiple frequencies at once? And if so, how can a wave be multiple frequencies at once, unless they're overlapping somehow?

Also, I'm reading about attenuation. Are radios like a sphere that radiates out from the transmitter, or are they emitted as many individual rays? And if the latter, is all the information "stored" in individual rays?

Also, how is it that waves of different frequencies pass through each other? How would they not combine into a net direction/magnitude upon "collision"?

>>8968631
you almost nailed it, forget the particles and the energy levels and you got it right, there is a field and the field value changes, goes up and down all the time, it is never quiet. If the oscillations follow certain pattern you got a wave. Now the cool stuff as any vibration can be decomposed in a sum of infinite sinusoidal functions no matter what happens there is always a ton of waves around.

>>8968607
You are correct, but the waves themselves are traveling at "c."
>>8968625
It's just light nigger.

Also, how is it that waves of different frequencies pass through each other?
they add together, you can add or subtract all the waves you want.
How would they not combine into a net direction/magnitude upon "collision"?
they can combine and you can get different phenomenons, interference is an example.

>>8968631
>SSB
When you amplitude modulate a carrier (generally sine) wave in the transmitter, it generates side bands. You can filter out the carrier and one sideband and just transmit the other one to save bandwidth, and the receiver reconstructs the original signal by adding back the carrier sine wave with an internal oscillator. Normal AM is the full modulated carrier wave and is demodulated with a simple detector, usually just a diode.

AM is better for expensive transmitters and cheaper receivers on bands that allow for more bandwidth use (commercial radio, certain ham calling frequencies, etc.), and SSB for less bandwidth use and specialized receivers (lower power ham on busier bands, other long-distance communication).

>>8968695
The physical result of an SSB transmission is more or less the audio signal pitch-shifted up to the transmission RF frequency, then the reception pitch shifts it back down by taking the difference with an intermediate frequency oscillator.

A transmitter can totally send more than one frequency at once. All the RF amplifier and transmitter antenna are seeing is a series of instantaneous potentials, not just a single frequency sine wave to send or not send. Same way your voice or a musical instrument can generate more than one frequency at once to make sounds of different timbres.

When charges accelerate they produce electromagnetic waves.

This releases energy. This can be achieved by sending alternating current up and down a length of wire (antenna). You can also achieve this by producing high energy electrons and slowing them down quickly like is done in a cathode ray tube to produce x-rays.

These propagate through empty space.

They don't require a medium because an EM wave is a composite of electrical and magnetic waves which mutually induce each other.

They pass through each other because they are composed of bosons which have integer spin.

When two bosons exchange position their combined wave functions remain unchanged. This allows them to occupy the same energy level in the same space without bumping into each other.

When an EM wave encounters a free electron it will bounce off with a different energy imparting some of it's momentum onto the electron (compton scattering).

When an EM wave encounters a bound charge system (atom of matter) it can be absorbed by that system putting it in a higher energy state (changes the electron orbital). This will only happen if the EM wave is a very specific range of frequencies (ask yourself why glass is transparent)

There are other things, but I'm done typing for now.