I've been reading recently about a mysterious and possibly hokey medical device of the 1930s. It was a variable-frequency radio emitter, invented by a Dr. Rife, which was supposed to kill various types of bacteria and viruses by emitting the resonant frequency of that particular species, like a wine glass being broken by the right musical note.
(N.B. This gadget is not to be confused with various so-called "Rife machines" currently being sold in New Age circles, many of which seem to have been built by people with a shaky grasp of physics and bear very little resemblance to the original ones.)
A paper by the American Cancer Society, mentioning Rife's research, states:
(Note: Although sound waves can produce vibrations that will break glass, radio waves cannot destroy bacteria due to their low energy level.)
That's all it said about that, it was mostly concentrating on the even less credible modern rip-offs and their claims to be able to cure cancer.
This is intriguing. I don't know enough about radio wave physics to answer this question, so I thought I'd put it to you. Theoretically, could radio waves of the right resonant frequency have enough energy to destroy a bacterium? What about a virus, which is usually much smaller?
If it's relevant, the output of the devices was from 50 watts to 500 watts depending on the model, and the power consumption was from 400 watts to 1,000 watts.
The frequencies used ranged from 100,000 to 1,700,000 Hertz.
Some examples of the infections it was alleged to be able to destroy included tuberculosis, tetanus, anthrax, gonorrhoea and typhoid.
The frequencies were determined empirically, according to Dr. Rife, by observing a microbial culture under a powerful microscope and going slowly through a range of frequencies until something happened, rather than by any theoretical calculation, so exactly what part of the microbe "resonated" and how (if indeed it did) is unknown.