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questions about photons and the physics of light

ossumguywill

ossumguywill

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for the last semester, I've been auditing an AP physics class and it left me with some questions.
First: Does all radiation have a fixed energy per wave, like photons? A photon has a fixed magnitude, do microwaves? If you want more microwave energy, can you up the magnitude of a single wave or do you have to make more of them (like photons)?
Second: Could we make laser light like we make radio waves? It seems to me like once our resonator tech makes it into the tens of terahertz range, we could generate light like we generate radio waves (eg, precise adjustable frequency). Is this correct, or is my understanding flawed?

I'm sorry if I got some of that wrong, I'm just going off what I remember here. Thanks!
 
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pullbangdead

pullbangdead

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ossumguywill said:
for the last semester, I've been auditing an AP physics class and it left me with some questions.
First: Does all radiation have a fixed energy per wave, like photons?
Second: Could we make laser light like we make radio waves? It seems to me like once our resonator tech makes it into the tens of terahertz range, we could generate light like we generate radio waves (eg, precise adjustable frequency). Is this correct, or is my understanding flawed?

I'm sorry if I got some of that wrong, I'm just going off what I remember here. Thanks!
Click to expand...

First, there is a fixed relationship between wavelength and energy, with Planck's Constant and the speed of light: E = (hc)/lambda. The same relationship holds for all wavelengths; gamma, x-ray, radio, microwave, UV, visible, IR (in no particular order).

Second, there is research going on in solid-state terahertz lasers, they exist, in addition to gas lasers that have existed for a long time. I don't know much about the field or how they do it, I do seem to recall someone posting around here a couple of times that was working on newer terahertz lasers. Does that answer your question?
 
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ossumguywill

ossumguywill

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pullbangdead said:
First, there is a fixed relationship between wavelength and energy, with Planck's Constant and the speed of light: E = (hc)/lambda. The same relationship holds for all wavelengths; gamma, x-ray, radio, microwave, UV, visible, IR (in no particular order).

Second, there is research going on in solid-state terahertz lasers, they exist, in addition to gas lasers that have existed for a long time. I don't know much about the field or how they do it, I do seem to recall someone posting around here a couple of times that was working on newer terahertz lasers. Does that answer your question?
Click to expand...
OK, thanks. For some reason I had it in my head e=hc/lambda only applied to certain parts of the EM spectrum, and the second part is helpful. I'm not super secure with my knowledge of radio/antenna, so I can't know for sure how it works but to the best of my knowledge if you jiggle an electron through a wire at a certain frequency, you get EM at that frequency so it seemed logical you could do the same with light. And of course, you could just be yanking my chain as a solid-state terahertz laser aptly describes a diode :D
 
pullbangdead

pullbangdead

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ossumguywill said:
OK, thanks. For some reason I had it in my head e=hc/lambda only applied to certain parts of the EM spectrum, and the second part is helpful. I'm not super secure with my knowledge of radio/antenna, so I can't know for sure how it works but to the best of my knowledge if you jiggle an electron through a wire at a certain frequency, you get EM at that frequency so it seemed logical you could do the same with light. And of course, you could just be yanking my chain as a solid-state terahertz laser aptly describes a diode :D
Click to expand...

Solid state describes a lot more than just diodes, no chain-yanking here.

But yeah, not my specific area of expertise.
 
ossumguywill

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alright, cool. Just another question, since you seem to know your stuff: is it a coincidence that these:
Hydrogen_Density_Plots.png

are the exact shapes of laser TEM modes?
 
pullbangdead

pullbangdead

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I don't really like the word coincidence, but how about this: similar math describes both situations very well. We often find repetitions of the same patterns in nature.
 
ossumguywill

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pullbangdead said:
I don't really like the word coincidence, but how about this: similar math describes both situations very well. We often find repetitions of the same patterns in nature.
Click to expand...
interesting. I can't wait until university when I stop learning this useless crap and get to choose my own courses so I can actually learn the stuff I see everyday :D
 
daguin

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pullbangdead said:
I don't really like the word coincidence, but how about this: similar math describes both situations very well. We often find repetitions of the same patterns in nature.
Click to expand...

This is one of the hardest lessons to learn in science.

Just because there "appears" to be a relationship, doesn't mean that there is.

Unfortunately, our feeble human brain wants to figure everything out based simply on what it can "see." Then when it realizes that it is incapable of figuring it out, (or just gives up) it uses magic and religion to fill the gap.

Peace,
dave
 
ossumguywill

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TEM modes are a punishment given to us by god, so that our divergence changes with temperature. We can only hope and pray.:bowdown:
 
pullbangdead

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Yep.

And to clarify my aversion to the word "coincidence" a bit: even if there isn't a causal relationship between 2 phenomena, there is a reason somewhere deeper that they both conform to the same mathematical relationships, even if it's not readily apparent. It's not a pure coincidence, because there is a reason why, even if there's not a direct relationship between 2 things.
 
ossumguywill

ossumguywill

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LOL and btw what looked like an "n" is pi, for some reason this font doesn't work very well with that character. πn, see the difference? Maybe in bold... πn or italics πn hmm nope.
 
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