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A comment on A radio frequency exposure test finds an iPhone 11 Pro exceeds the FCC's limit. Parent comment

Re:A radio frequency exposure test finds an iPhone 11 Pro ex... by krastanov on Friday February 14, 2020 @11:35AM (#22327898)
So it is doubly incorrect... They are completely misusing the word exponential to mean quadratic which is already incredibly annoying, but it is not even quadratic, it is constant.
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Re:A radio frequency exposure test finds an iPhone 11 Pro ex... by whatshisface on Friday February 14, 2020 @11:44AM (#22327971)
Not squared, inverse square. That's faster than exponential.
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Re:A radio frequency exposure test finds an iPhone 11 Pro ex... by AnimalMuppet on Friday February 14, 2020 @11:46AM (#22327993)
You may need to check your math. Inverse square does not fall off faster than exponential.
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Re:A radio frequency exposure test finds an iPhone 11 Pro ex... by whatshisface on Friday February 14, 2020 @12:01PM (#22328115)
1/x² has a singularity and rises faster than exponential as you approach it. We're talking about getting closer to the source, not further.
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Re:A radio frequency exposure test finds an iPhone 11 Pro ex... by AnimalMuppet on Friday February 14, 2020 @12:37PM (#22328385)
Ah, I see. In that direction, you are correct.
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Re:A radio frequency exposure test finds an iPhone 11 Pro ex... by Retric on Saturday February 15, 2020 @05:20AM (#22334402)
It should be obvious that real world antenna don’t behave this way as they are not point sources. But, mathematically you’re correct.
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Re:A radio frequency exposure test finds an iPhone 11 Pro ex... by whatshisface on Saturday February 15, 2020 @10:40AM (#22335855)
As you get closer and closer to the surface of the phone, phenomena progress from a visible glow, to pair production, to the thermodynamic stability of quark-gluon plasma.
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Re:A radio frequency exposure test finds an iPhone 11 Pro ex... by krastanov on Friday February 14, 2020 @11:58AM (#22328077)
No. All polynomials and rational functions fall off drastically slower than exponential.
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Re:A radio frequency exposure test finds an iPhone 11 Pro ex... by whatshisface on Friday February 14, 2020 @12:00PM (#22328099)
We're talking about the rise in power as you get closer. 1/x² has a singularity, I doubt exp(x) can beat that...
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Re:A radio frequency exposure test finds an iPhone 11 Pro ex... by tomrod on Friday February 14, 2020 @12:29PM (#22328328)
Good point! -ln(x) may (would have to check), but exp(0) = 1 and 1/02 is defined as positive infinity (the Real numbers are not closed under division).
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Re:A radio frequency exposure test finds an iPhone 11 Pro ex... by enedil on Friday February 14, 2020 @03:24PM (#22330055)
No, division just isn't a total function.
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Re:A radio frequency exposure test finds an iPhone 11 Pro ex... by tomrod on Friday February 14, 2020 @04:16PM (#22330474)
I think these may be the same thing in this case.
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Re:A radio frequency exposure test finds an iPhone 11 Pro ex... by fulldecent2 on Friday February 14, 2020 @10:23PM (#22332972)
I'm following along in this thread here and double checking everybody's math.

So... does this mean I will die from radiation or not?

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Re:A radio frequency exposure test finds an iPhone 11 Pro ex... by whatshisface on Friday February 14, 2020 @11:38PM (#22333308)
This thread is actually irrelevant to the radiation question due to the plane radiator thing mentioned above.
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