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I sorta agree with you, but to be a pedantic bastard, a single hydrogen atom can absorb and emit 21cm radio wave[1], so molecular sizes don't completely rule ou

I sorta agree with you, but to be a pedantic bastard, a single hydrogen atom can absorb and emit 21cm radio wave[1], so molecular sizes don't completely rule out radio absorption. [1] https://en.wikipedia.org/wiki/Hydrogen_line https://en.wikipedia.org/wiki/Hydrogen_line

acqq 8y ago
But note that that kind absorption doesn't mean that such hydrogen atom becomes "less" or more the same "hydrogen" than before. The electron remains "there" in both states: its magnetic moment gets to be either parallel or anti-parallel to that of the proton, that's all. Also note that the "mean lifetime of the excited state" of that electron which still remains bound to the proton (that is, of the "higher energy" moment of the electron) is "of around 10 million years." So all this is relevant for the observations of the light passing through the universe, that is, when we worry about the photons traveling the many light years of space, but not relevant when we worry about if electrons remain by the same atom or not. Compared to all that, the ionizing radiation (UV and shorter, that is, measured in nanometers or smaller, and not in centimeters) does remove or add the electrons around, changing the properties of the atom, and as soon as the electron is being hit by the photon. That is why it is provably damaging. Of course, there's never only one wavelength of the photons, it's always a distribution. https://en.wikipedia.org/wiki/Sunlight#/media/File:Solar_spectrum_en.svg https://en.wikipedia.org/wiki/Sunlight#/media/File:Solar_spe... But that would still mean that the potential for the damage is order of magnitudes bigger by the "plain" light than by the infrared, micro, radio or 60 Hz waves. The photon energy is proportional to the frequency (i.e. more Hz more energy): https://en.wikipedia.org/wiki/Planck%E2%80%93Einstein_relation https://en.wikipedia.org/wiki/Planck%E2%80%93Einstein_relati...

acqq 8y ago

But note that that kind absorption doesn't mean that such hydrogen atom becomes "less" or more the same "hydrogen" than before. The electron remains "there" in both states: its magnetic moment gets to be either parallel or anti-parallel to that of the proton, that's all. Also note that the "mean lifetime of the excited state" of that electron which still remains bound to the proton (that is, of the "higher energy" moment of the electron) is "of around 10 million years." So all this is relevant for the observations of the light passing through the universe, that is, when we worry about the photons traveling the many light years of space, but not relevant when we worry about if electrons remain by the same atom or not. Compared to all that, the ionizing radiation (UV and shorter, that is, measured in nanometers or smaller, and not in centimeters) does remove or add the electrons around, changing the properties of the atom, and as soon as the electron is being hit by the photon. That is why it is provably damaging. Of course, there's never only one wavelength of the photons, it's always a distribution. https://en.wikipedia.org/wiki/Sunlight#/media/File:Solar_spectrum_en.svg https://en.wikipedia.org/wiki/Sunlight#/media/File:Solar_spe... But that would still mean that the potential for the damage is order of magnitudes bigger by the "plain" light than by the infrared, micro, radio or 60 Hz waves. The photon energy is proportional to the frequency (i.e. more Hz more energy): https://en.wikipedia.org/wiki/Planck%E2%80%93Einstein_relation https://en.wikipedia.org/wiki/Planck%E2%80%93Einstein_relati...