EM Spectrum Questions from a lay-person:

 

What are the upper and lower limits of the spectrum? I mean the uppermost- and lowermost-possible wavelengths.

 

Also, what defines the endpoints of the spectrum? There must be some law/relationship between wavelength and energy that constrains the EM spectrum to upper and lower bounds.

 

Diagrammes of the spectrum show it as a continuum; are gamma rays really the same as radio waves, just shorter wavelength/higher energy photons?

 

As I said, I am just a lay-person trying to learn. Please try to keep your answer simple (if possible). TY!

 

Diagrammes of the spectrum show it as a continuum; are gamma rays really the same as radio waves, just shorter wavelength/higher energy photons?

 

Yes, but we don't use gamma rays to carry signals.

 

What are the upper and lower limits of the spectrum? I mean the uppermost- and lowermost-possible wavelengths.

 

Also, what defines the endpoints of the spectrum? There must be some law/relationship between wavelength and energy that constrains the EM spectrum to upper and lower bounds.

 

 

 

No there is no law concerning this.

 

There is no reason to assume any upper limit, just because we have not yet encountered such waves.

 

We normally take zero (the stationary steady state) as the lower limit for real waves, but negative frequencies may be used in mathematical theory. Negative frequencies again have no lower bound.

The naming is just for organizational purposes. It's all EM radiation, but the energy (or frequency, or wavelength; they're all related) dictates what interactions they are likely to undergo.

Energy of photons that we detect is correlated to source material objects that emitted them in the past.

 

See also article about very high energy gamma photons on wikipedia:

https://en.wikipedia.org/wiki/Very-high-energy_gamma_ray