I was always puzzled by the fact that while almost all Planck units are extreme (very high or very low), Mass and Energy are exception from that rule. Planck mass is in the ‘middle’ of the spectrum, and it divides the mass spectrum into 2 parts:(adsbygoogle = window.adsbygoogle || []).push({});

- For small masses/energies m << Mplanck we can define a wavelength corresponding to the energy (E=hv).
The higher energy – the shorter wavelength.- For big masses we can define Schwarzschild radius Rs which is proportional to mass (and as I noticed in Black Hole physics scientists think in Rs units, substituting R with M).
So, the higher energy – the longer wavelength.

So the same length corresponds (in Planck’s sense) to 2 masses: one light and one heavy. And there is also a correspondence (mapping) of heavy masses into light masses and vice versa. Assuming that Planck units are natural such mappings must be important, but so far I haven’t heard anything about it.

This is really weird. Any thoughts? (or URLs?)

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# Planck Units: Mass and Length

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