Thread: Radio wave exposure

The main source of visible light is the sun (for human beings).
The main source of heat is the sun.

This induce me to think that the main source of radio waves that we are receiving is the sun. But this is only an intuitive thought, not based on any scientific data.

Does anybody has serious information about the ratio of solar radio waves we are dealing with, compared with radio waves emited by men ?

Originally Posted by caKus

The main source of visible light is the sun (for human beings).
The main source of heat is the sun.

This induce me to think that the main source of radio waves that we are receiving is the sun. But this is only an intuitive thought, not based on any scientific data.

Does anybody has serious information about the ratio of solar radio waves we are dealing with, compared with radio waves emited by men ?

Virtually all of the energy we receive from the sun is in the form of photons. If you define "radio waves" broadly as "any electromagnetic radiation" then the sun delivers roughly a kilowatt per square meter of "radio waves" to the earth's surface (this is a rough number, but correct to within a factor of several).

Humans aren't generating anywhere near the energy that the sun puts out (otherwise we'd be a sun, too), so the electromagnetic energy we encounter is almost entirely due to the sun.

More relevant to biology, the radio waves we use to communicate are in frequency bands far too low to break bonds found in tissues, and thus they can't induce cancers, etc., despite the fear-mongering nonsense that you encounter regularly in the press. So, the dominance of the sun's energy is even greater for biology.

I'm not sure this gives details of the strength of RF signals from the sun, but is interesting anyway: British Astronomical Association - Radio Astronomy Group

Originally Posted by tk421

Virtually all of the energy we receive from the sun is in the form of photons.
.........frequency bands far too low to break bonds found in tissues, and thus they can't induce cancers, etc., despite the fear-mongering nonsense that you encounter regularly in the press. So, the dominance of the sun's energy is even greater for biology.

Photons being non-particulate in nature, is that correct? Thus, virtually all of the sun's energy is electromagnetic in nature?

How can we be absolutely certain that the "fear-mongering" has no basis in fact? By "break bonds in tissues", you mean chemical bonds? Is it necessary to break bonds in order to induce illness? How about considering the ability of those seductive-looking hormone-mimicking substances which throw the natural scheme "out of whack"? Strike that, if you will, as off-topic. jocular

Originally Posted by jocular

Photons being non-particulate in nature, is that correct? Thus, virtually all of the sun's energy is electromagnetic in nature?

The above makes little sense to me, taken together. Photons are the carriers of the electromagnetic force. They have both a wave and particulate nature.

How can we be absolutely certain that the "fear-mongering" has no basis in fact?

"Absolute" certainty is not possible, but for all practical purposes, we may be certain that this fear-mongering is BS. If you don't break bonds, you can't create new compounds, including those associated with disease. QED, unless you want to invoke phenomena outside of science.

At a given temperature, the mean thermal energy is of the order of kT (for purposes of this discussion, we'll treat the 3/2 factor as unimportant). That corresponds to a frequency of about 7THz (7,000GHz). I did that in my head, so I may be off by factors of a couple or so, but you get the idea: Until the RF signal reaches a frequency of thousands of gigahertz, thermal energy dominates. As all RF signals used for communication lie orders of magnitude below this threshold, their effects are entirely negligible, compared to thermal energy.

Before you invoke "resonance" (as many woo-meisters do), understand that biological tissues are highly dissipative. That is, their resonant properties are similar to the acoustically resonant properties of a ball of mud.

By "break bonds in tissues", you mean chemical bonds?

Yup. What other types of bonds were you thinking of?

Is it necessary to break bonds in order to induce illness?

See above.

How about considering the ability of those seductive-looking hormone-mimicking substances which throw the natural scheme "out of whack"? Strike that, if you will, as off-topic. jocular

Again, merely compare the energy of the RF signal with the thermal energy. That's all you need to know.

Footnote: There is a subtlety that needs to be acknowledged: If you deliver enough RF energy to tissues to heat them up (regardless of the frequency used to do so), you'll cook them. This is the result of a conversion of a low-entropy energy source (narrow band RF signal) into a high-entropy (blackbody-like) broadband RF spectrum, thanks to thermal equilibrium. The shorter wavelength components can be of sufficiently high frequency to cook tissue. That is, in fact, how microwave ovens work.