I’m watching S1 of this War Of The World tv series. I’m finishing up S1 and will stop; only S1 is available free. More importantly, the series is just annoying. Largely unlikeable characters and a lot of whiny bitches (not necessarily female). It may have been interesting if the characters were more Red Dawn rather than, I don’t know, what it was. I get that all types of people exist, but why include the idiots in these entertainment programs?

Anyway, I wanted to ask about natural frequencies. There was a contention in the story that the monitoring for ET was based on detection of frequencies that don’t naturally occur.

What are these natural frequencies and what are their sources?

On the assumption that we’re exposed to perhaps limited samples of what is available in the universe, how do we determine what is natural vs artificial when encountering a new frequency?

Noise

Ask Kenneth.

I hear that’s how they built the pyramids.

Dunno.

Maybe "Whistlers" produced by lighting might be a good starting point, but beyond that, I'm lost. When I think natural frequency I normally think about someone plucking a guitar string or blowing into a pipe, and extrapolating from there. Well, then there's that Tacoma Narrows Bridge in Washington.

Lighting produced whistlers....

https://en.wikipedia.org/wiki/Whistler_(radio)

Well, there's the movie "Contact".
I think they listen for unnatural patterns. Back in the 90's I ran the SETI program on my computer. I thought it was cool.

https://youtu.be/NCkbekhUdw4?t=6

https://youtu.be/-ciK05XqlOw

quote:

Originally posted by eyrich:
https://en.wikipedia.org/wiki/Hydrogen_line

Cool. Conceptually get it. But that page gave me a headache.

So, one wonders, for movies and theories like this: 1) is EM the only presumed method of communication; 2) what band do we assume we would observe something (for example, if ET is out there and much more advanced than us, perhaps they are using bands that are a million times higher than gigahertz - we started in Hz and now we're just entering the gigahertz band for comms; monitoring megahertz may be too simple of a band).

Anyway, just casually curious.

Is there an unnatural frequency?

More than noise to me ... depending on the metallic hat that I am wearing I get everything from talk radio to old classic rock and roll. :P

Frequencies are a continuum. None are special. My 2¢.

Different nuclear reactions/interactions produce characteristic frequencies of light/x-rays/etc. See something else, and it is an indication that it might be artificially produced, or, perhaps, a reaction that hadn't been observed in the lab. Analogous to picking out vocal frequencies in an audio recording, you may not know what is being said, but you can be pretty sure it is a human voice.

Yes. So in the context of the series, one assumes that the scientists have a good understanding of what frequencies are prevalent in the background across the measurable spectrum. And also have been able to determine the source of each observable frequency. Anything different and/or of higher amplitude my be modulated artificially.

Not sure how good these assumptions are pragmatically but anyway, it’s just fictional entertainment. I learned about hydrogen lines at least - something new for today.

quote:

Originally posted by Pipe Smoker:
Frequencies are a continuum. None are special. My 2¢.

Bingo.

OP -- Electromagnetic radiation varies from the very high frequency & high energy (gamma rays) to the very low frequency & low energy (radio waves). Kind of in the middle is visible light, which is framed by ultraviolet on the higher end and infrared on the lower end. Pick a frequency of radiation, and there is likely some natural cosmic event that produces that frequency.

Understand that radiation frequencies aren't absolute or unchanging over time. Think of the Doppler effect with sound. Cosmic radiation loses energy & drops in frequency as it travels great distances in space. Discovering the cosmic microwave background in the mid 1900's is one example. The James Webb telescope is a more recent example -- the Webb detects lower energy infrared light better than the Hubble telescope, which helps it "see" older and more distant stars.

They are only natural when unaffected by
Surrounded energies.

Obtaining the unadulterated
Sounds with the ears isn't possible because we don't come close to hearing the whole spectrum.

Imagine trying to hear every sound made in earth at one time and then realizing that ninety percent of those sounds were tweaked by wind ,rain, hard surfaces very soft surfaces.