Speaking of sending out long-wavelength signals with smaller antennas, I learned while reading about CEMI theory that the weak electromagnetic waves emitted by the human brain are mostly at about 40Hz, and thus the wavelengths are roughly 7500km. Kind of odd to think that my thoughts are stretching way out into space. 
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Try telling that to the professors I work with — using the phrase “fringe idea” around a string theorist is like waving a red flag in front of a bull. 
We certainly don’t know exactly what physics looks like at the Planck scale, but given how badly well-established physics crashes & burns at this scale, it’s not unreasonable to speculate that some kind of radical change happens up there. Moreover, absent some radically new physics, that’s the only place that such a break-down could occur. I’ll concede, though, that physicists are far from agreeing on what would happen at such high energies.
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