Hello,

(I hope this question hasn't been beat to death already. I couldn't find it in a search.)

Without a medium to travel in and through, how do microwaves and radio waves travel through the vacuum of space?

Thanks!
Jeff

They are both composed of photons, the same type of energy as visible light, ultraviolet, infrared, x-rays, etc. These act as particles and travel through space without a medium.

__________________
"If this were play'd upon a stage now, I could condemn it as an improbable fiction."
Shakespeare, Twelfth Night
Illuminati's Razor-The most complicatedly evil answer is usually the most correct answer. - Fazor
"Every book is a children's book if the kid can read." - Mitch Hedberg
"Distance doesn’t matter much in space, where if you just start a thing off with the right kind of shove, sooner or later it will get where you want it to go." -Frederik Pohl, Mining the Oort

Well, they obviously DO, so in the context of electromagnetic waves, the idea that "waves" need some medium within which to travel is obviously wrong.

Maybe the problem with visualization or conceptualization stems from the fact that electromagnetic waves are quite different than ripples in a pond or sound waves or seismic waves. Certainly electromagnetic waves have certain wave qualities, but they also have the qualities of particles, and in recognizing this you have opened the door to the quantum realm, where lots of qualities and effects go against normal common sense derived from the history of human experience prior to the 1930s.

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Everyone is entitled to his own opinion, but not his own facts.

Thanks for your help in thinking this through. Since being taught about "waves" as a child, I was given the ripple in a pond analogy and came to think of radio waves in the same realm. Radio, infrared, and visible light all being on the same electromagnetic spectrum puts this all in a clearer perspective for me. I just didn't think about it this way, but it clicked when you both connected the pieces.

Jeff

Also, note that your question is very profound, and would have received an entirely different answer just 105 years ago. Back then it was thought that all waves required a medium. Now we know that the wave phenomenon is far more fundamental than that-- it pervades the motion of all particles, of everything. So waves in a medium are actually just a kind of superficial example, sharing the same mathematical features of this much more widespread phenomenon.

The ether.

That's ether true or false.

__________________
"If this were play'd upon a stage now, I could condemn it as an improbable fiction."
Shakespeare, Twelfth Night
Illuminati's Razor-The most complicatedly evil answer is usually the most correct answer. - Fazor
"Every book is a children's book if the kid can read." - Mitch Hedberg
"Distance doesn’t matter much in space, where if you just start a thing off with the right kind of shove, sooner or later it will get where you want it to go." -Frederik Pohl, Mining the Oort

If you dig deep enough, you will find that answers like "Well, they obviously DO, so in the context of electromagnetic waves, the idea that "waves" need some medium within which to travel is obviously wrong." to be wholly unsatisfying. If you look wide enough for a theory that encompasses all phenomena, you will also find that answer is useless in its application.

Say what?

__________________
"If this were play'd upon a stage now, I could condemn it as an improbable fiction."
Shakespeare, Twelfth Night
Illuminati's Razor-The most complicatedly evil answer is usually the most correct answer. - Fazor
"Every book is a children's book if the kid can read." - Mitch Hedberg
"Distance doesn’t matter much in space, where if you just start a thing off with the right kind of shove, sooner or later it will get where you want it to go." -Frederik Pohl, Mining the Oort

So you, of course, have an answer for the OP's question to share with us, right? Something positive to add to the discussion?

...Keeping in mind, of course, the forum's rules?

__________________
"If this were play'd upon a stage now, I could condemn it as an improbable fiction."
Shakespeare, Twelfth Night
Illuminati's Razor-The most complicatedly evil answer is usually the most correct answer. - Fazor
"Every book is a children's book if the kid can read." - Mitch Hedberg
"Distance doesn’t matter much in space, where if you just start a thing off with the right kind of shove, sooner or later it will get where you want it to go." -Frederik Pohl, Mining the Oort

Actually, they do travel through a medium: space-time.

I think it's been rather clearly demonstrated that gravitational gradients within the space-time continuum affect the velocity at which EM fields propagate.

__________________
I am Mugs, of the Alien clan of Usa, Nordamerica, a Terran, of Sol.

Perception isn't reality. It's merely an abstraction thereof, and quite often not a very good one at that.

I am human. Fully human.

I find the concept of an "ether" fascinating.

The only way I can visualize it coherently, is to imagine that every place that there is....all of space is comprised of little plusses and minuses everywhere, and no two of the same touch. Like a cube or a sphere filled with red and blue marbles with no two of the same color connecting. So when you put your hand in the sphere, they keep that property even though you are making them get out of your way.

You are certainly correct that we can use a theory of gravity to understand how light propagation can be altered, yet even sound waves must respect it-- and we would not call spacetime the medium of a sound wave. One might be tempted to call spacetime the medium of gravity waves, I'll leave that to the "high-priests" of gravity waves-- but spacetime is something more fundamental than a wave medium, and I think it is still fair to say that waves do not require a physical medium at all, the thing that is "waving" can be an entirely mathematical construct that cannot itself be detected directly. In fact, that might be the most important thing of all to know about waves, which came as a very large surprise in the 1920s when it was learned that all particles obey wave mechanics.

Yes, the question for me that is really interesting is this: we know from the slit experiments that particles have both particle and wave properties. And the particle properties are quite easy to understand. But how do they acquire wave properties without a medium?

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As above, so below

Sounds like the vibration of those "strings".

You can "wiggle" whether in space, or the ocean. You just wiggle differently.

Jeff. "Space" is not empty, even though it has little in the way of solids, liquids, gases, and plasmas.....on average. The concept of vacuum as nothingness is not particularly fruitful, or true, and as Asimov wrote in his treatise "On Physics", only one of the four physically valid interpretations of the negative result of the Michelson-Morley experiment was that there was no ether...(the popular one, because it's simple). Space is filled with neutrinos, and antineutrinos, amongst other things. Pete.

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A third rate theory forbids
A second rate theory explains after the fact
A first rate theory predicts...A. Lomonosov

Just as gravity pulls matter, it also pulls photons. Thus gravitational effects on EM need not be attributed strictly to a medium.

__________________
"If this were play'd upon a stage now, I could condemn it as an improbable fiction."
Shakespeare, Twelfth Night
Illuminati's Razor-The most complicatedly evil answer is usually the most correct answer. - Fazor
"Every book is a children's book if the kid can read." - Mitch Hedberg
"Distance doesn’t matter much in space, where if you just start a thing off with the right kind of shove, sooner or later it will get where you want it to go." -Frederik Pohl, Mining the Oort

That might be a bridge too far for science to answer. But I will point out that actually it might be the "particlelike" aspects that are more bizarre than the wavelike ones, where by "particlelike" I mean the common misnomer of the concept of a trajectory. You see, the great thing about a wave is that it propagates by constantly re-creating itself; every part of that wave is both a source of the new wave, for the next instant, and the means of the replacement of the old wave-- all via interference. Interference explains how the wave of "now" is replaced by the wave of "a moment later", continuously-- it destructively interferes the old wave into oblivion and constructs the new wave slightly displaced: motion in a nutshell. But how does the concept of a trajectory work? How does a bullet move, how does it know that it can't be in the old location but has to keep on showing up at some new location all the time, based on some strange property we call "speed" but don't know how a bullet "knows" its own speed? Waves take care of all that, we're just more used to trajectories: it's an example of how easily familiarity is mistaken for understanding.