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Don't Panic

Power Line Panic and Mobile Mania

Headlines in the news periodically highlight the “latest” investigation into the link between cancer and either use of mobile (cell) phones or residing near power lines. Some reports claim that there is statistically significant evidence for such linkages yet others deny this. However, both typically include a disclaimer that “scientists claim that there is no physical basis for such a linkage.” The purpose of this piece is neither to investigate the large amount of data that has been generated nor to persuade the public health authorities on the utility (or otherwise) of such investigations. It is to bring out as clearly as possible what scientists mean when they say “there is no physical basis for such a linkage.” The strength of this argument may enable

individuals to be less worried about this “panic and mania.”

What is the physics underlying the operation of both power lines and cell phones? Quantum mechanics. How well is this theory established? If this theory were used to calculate the diameter of Earth using paper and pen, one would get a value that agrees with the measured value within the thickness of a human hair. There is really no “experimental” reason to doubt quantum mechanics. It can be called the crown jewel of all science.

What is the relevant idea of quantum mechanics we need to understand power lines and cell phones? The first idea is that all electromagnetic radiation consists of small particles called photons. The energy of a photon is determined by a formula called Planck’s law: the energy of the photon increases as the frequency increases. . .


 

Comments

The power line / cell phone article is great and a nice follow up to my comment on the cell phone Alheimer's cure nonsense. One huge error, however:

Now consider a photon of yellow light. This has a frequency of some 531014 Hz...

Not quite. A 2.0 eV (yellow) photon has a frequency of about 4.84 × 10¹⁴ Hz (484 THz) or a wavelength of 620 nm. How does a physicist not catch an error of 9 orders of magnitude?

Wow, now that I read further I see that ALL his frequencies are crazy! Cell phones use frequencies in the 300 MHz – 2 GHz range, not 13109 Hz! The X-ray photon frequency is similarly crazy. Who is this guy?

The article had me scratching my head for a moment, then I realized the numbers were screwed up because of lost formatting. The decimal points and symbols are missing, and the exponents are not in superscript. "531014 Hz" should probably read "5.3 × 10¹⁴ Hz", etc.

You're right, I just looked at the article in my copy of the "Skeptical Inquirer" magazine and that is indeed what happened. The numbers there are as you surmised.

That makes much more sense. I would have caught it but his frequencies are rough - so when I calculated 2.0 eV the result wasn't off by enough that it didn't register (5.3 × 10¹⁴ Hz is 2.19 eV).

Glad someone else noticed those whacky numbers. I was wondering if there was an error in translation or notation. A published article last week came out showing that cell phone EM radiation halts or reverses plaque build-up in the brains of mice with Alzheimer's. If it can affect proteins this way, it can probably effect DNA in some way.

If it can affect proteins this way...

That's the point: IF it can affect proteins this way - but I strongly doubt that it can.

If 400 MHz radiation can affect proteins, then every NMR protein crystal structure ever determined is subject to doubt. In fact, virtually all organic chemical analysis performed in the past 50 years is thrown into question since NMR spectroscopy involves absorption and emission of frequencies in just that range when 10 Tesla magnetic field (typical in a modern spectrometer) is applied. Again, I'm betting that the claim that cell phone radiation really reverses plaque is is irreproducible. If it is reproducible, then it will be fascinating to learn the mechanism whereby photons with energies that are 7 orders of magnitude too small to effect chemical changes (and total power levels of about one watt) manage to inhibit the activity of just certain proteins in the brain.

That should have read 5 orders of magnitude, not 7 ...

Understanding the math behind Quantum Mechanics is vastly different than understanding its potential effects on biology. That is why you do experiments.

Frankly, I doubt all new technology to some extent, as those that desire our hard earned cash rarely think of our safety (beyond the potential for a class action law suit).

I'm not paranoid, but I am prudent.

See this youtube video on cell phone popping popcorn as evidence:

http://www.youtube.com/watch?v=ZEl7QqoPH9c

(watch it before commenting *8) )

It's nice to have readers who have the scientific knowledge to speak to articles such as this.

However to the question of the relative energy of different photons and the absorption where do cell phones and powerlines stand in relation to such things as UV light and x-rays and other sources that are known to cause damage.

it's not just nice it's friggin' awesome. dr. timothy rules.

now if only a scholar of religion(s) (not me) could get the same respect around here. but you guys don't like oxymorons, i understand.

Here is a diagram showing energy scales for various wavelengths/frequencies of radiation and typical physical/chemical events that such radiation can give rise to. Cell phone radiation lies from 3 × 10⁹ Hz to 2 × 10¹⁰ Hz (down there at the low end of the molecular rotation energies, EPR and NMR. These energies are roughly 5 orders of magnitude lower than the energy of green light that chlorophyll uses to convert visible radiation into chemical energy - which is still a bit less (a factor of ~2) than the UV radiation needed to do cellular damage.

Microwave radiation "does chemistry" by the use of sheer power - so many microwave photons are absorbed by highly absorbing substances (things with high dielectric constants like water) that it creates thermal effects. That's why I mentioned the power of a cell phone - about one watt - and that power isn't focussed in a standing wave pattern like in a cavity in the center of a microwave oven.

user-pic

"Most of the molecules in the human body are polymers..." I would agree if he had written "most of the kinds of molecules," but given that you and I are 70% water molecules I don't think the statement stands. If it doesn't, the claimed consequence that we don't get heated by microwave radiation because we are mostly polymers also doesn't stand, and that is consistent with what we see when we cook bacon in a microwave. There's not too many differences between bacon and longpig. The fact the bacon sizzles on the inside and we don't on the outside is due to shielding and the inverse square law!

Don't get me wrong - I'm not saying microwaves are carcinogenic, just pointing out an error in the article.

The article's author makes an absurd claim in relation to Quantum Mechanics:

If [QM] were used to calculate the diameter of Earth using paper and pen, one would get a value that agrees with the measured value within the thickness of a human hair.

This assertion makes no sense at all.

  1. The surface isn't so regular that there is a "diameter" to calculate.

  2. If he's just trying to impress the reader with the precision of QM, then he's completely forgotten the fact that it's a statistical theory.

I think he's making the same kind of analogy that Richard Dawkins makes when he cites the accuracy of quantum electrodynamics (in particular with respect to its accuracy in calculating the electron g-factor). This is an analogy that I've heard Feynman himself make and, if I recall, they make a comparison with measuring the distance between New York and San Francisco within the width of a human hair. I am sure that Feynman knows that imprecision with which one defines "New York" and "San Francisco" makes the analogy literally absurd, but he's just trying to connect with a general audience with some distances they are familiar with.

I'm not sure what you point is concerning the statistical nature of QM.

My point about the statistical nature of QM is that the physical world is soft and smudgy even when you're not dealing with a more-or-less oblate spheroid with fractal distortions of the surface.

The author at hand isn't using an analogy: he states that you can literally calculate, "using paper and pen", the diameter of the earth using QM. He does not compare one activity with another to relate scale.

When and where did you hear Feynman draw this analogy? Did he couch it as an analogy as he spoke? Is it in the Caltech lectures?

Here is Feynman in print; but in stead of San Francisco it was Los Angeles. - and I think I actually heard it as well - maybe the Caltech lectures. It seems to me that the analogy is implicit, but if you feel more comfortable just calling it a comparison, then OK:

Just to give you an idea of how the theory has been put through the wringer, I'll give you some recent numbers: experiments have Dirac's number at 1.00115965221 (with an uncertainty of about 4 in the last digit); the theory puts it at 1.00115965246 (with an uncertainty of about five times as much). To give you a feeling for the accuracy of these numbers, it comes out something like this: If you were to measure the distance from Los Angeles to New York to this accuracy, it would be exact to the thickness of a human hair.

Multiply 1.00115965246 by –2 and you get the electron g-factor, which, in my most recent list of physical constants from NIST, is even more precise now:

−2.0023193043622(15)

(This is currently the most precisely determined physical constant in nature, so far as I know.)

Ooops, I gave the number wrong. Dirac's number (experimental) is now determined to be:

0.00115965218111(74)

You add that to 1 and multiply by –2 to get the electron g-factor above.

Hey, check out the linked article. I sent them an email and they've fixed it.

Hi everyone! I have always been curious: Why is it that there is nothing to worry about w/r/t cell phones and the human body, but I have to turn it off on the plane and/or in the hospital?

I suppose instead of all this physics and energy levels and such that I know nothing about, I would like an article that explains how cell phones disrupt other man-made electronics and why that is inoperative to biological systems.

(Or did I miss it?)

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