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A comment on Inaccurate chart led to unwarranted fears of 5G wireless technology. Parent comment

Re:Inaccurate chart led to unwarranted fears of 5G wireless ... by deogeo on Tuesday July 16, 2019 @08:55PM (#20455450)
> EM fields are not affecting protein folding.

Why not? The energy needed to affect that is lower than ionization energy, so they could.

And I'm not "reacting" to anything. 60 GHz radiation is sufficiently different from sunlight that it might plausibly have a different effect on us (such as by interacting with some low-energy absorption peak of a protein that visible light does not interact with due to its higher energy, or by penetrating deeper into tissue than visible light can).

It turns out studies show it is not harmful. But they conducted actual studies to show that - they didn't dismiss it outright "because sunlight".

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Re:Inaccurate chart led to unwarranted fears of 5G wireless ... by Dylan16807 on Wednesday July 17, 2019 @03:07AM (#20457201)
Sunlight bathes you in multiple watts in the same narrow frequency range, so it couldn't do that much.
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Re:Inaccurate chart led to unwarranted fears of 5G wireless ... by deogeo on Wednesday July 17, 2019 @10:55AM (#20460122)
Surely it's a different narrow frequency range? Otherwise sunlight would act as a signal jammer, a source of noise that drowned out our wireless signals?
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Re:Inaccurate chart led to unwarranted fears of 5G wireless ... by itcrowd on Wednesday July 17, 2019 @11:27AM (#20460479)
Indeed, the radiation coming from the sun in the visible spectrum is much larger than the microwave radiation coming off it [1]. Note: the microwave spectrum ends at ~300 GHz or 1 mm wavelength, that is 1 million nanometers, so the scale on the x-axis is wayyy too short in the image. The actual value is very, very low.

[1] https://upload.wikimedia.org/wikipedia/commons/0/0d/Effectiv...

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Re:Inaccurate chart led to unwarranted fears of 5G wireless ... by Dylan16807 on Wednesday July 17, 2019 @04:38PM (#20463735)
You can filter out a stable amount pretty easily but oops I just checked the blackbody math again and an exponent flipped when I changed one of the ranges while everything else stayed almost the same, I screwed up and ignore everything I said.
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Re:Inaccurate chart led to unwarranted fears of 5G wireless ... by deogeo on Wednesday July 17, 2019 @05:38PM (#20464328)
Hehe, happens :)

But, suppose the sun did interfere - how would you filter this out? Due to the black-body nature of the source, the amplitude would be stable, but the phase wouldn't be - you'd get entirely uncorrelated white noise, right? How can you filter that?

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Re:Inaccurate chart led to unwarranted fears of 5G wireless ... by itcrowd on Thursday July 18, 2019 @11:00AM (#20470513)
Good question. A good but short answer is given on Wikipedia (https://en.wikipedia.org/wiki/Matched_filter#Matched_filter_...). Any undergraduate textbook on digital signal processing should have details on this topic.

edit: to add to this, the capacity C ("throughput") of the communications channel is linear with bandwidth B (in Hertz) but only logarithmic (log_2) with noise power N. This was derived by Shannon (https://en.wikipedia.org/wiki/Shannon%E2%80%93Hartley_theore...) and in equation form:

  C = B*log_2(1+S/N)
Example: signal to noise ratio is 1 (S/N = 1). Result:

  C = B
Now we increase the bandwidth of our channel by a factor of 10, keeping the signal power equal. This will lead to a factor 10 more noise power (S/N = 1/10). Result:

  C = 10*B*log_2(1 + 1/10) = 1.38*B
So we can improve the channel capacity by increasing the bandwidth even in a noisy channel.
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Re:Inaccurate chart led to unwarranted fears of 5G wireless ... by Dylan16807 on Wednesday July 17, 2019 @09:48PM (#20465944)
I've never really looked into how the encoding is typically done on those bands. You don't need a lot of bits per Hz when you have 14GHz of space, so nothing particularly elaborate with phase is strictly necessary. But yes it would definitely hurt speeds, and you have a good point in that it's something to consider as a sanity check!
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Re:Inaccurate chart led to unwarranted fears of 5G wireless ... by XorNot on Wednesday July 17, 2019 @06:58AM (#20458147)
Do you know anything about protein folding or just the term? Because everything you just wrote is reactionary jibberish and not based on any possible mechanism, or even a solid understanding of how protein folding works.
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