Posted: Jan 06, 2019 5:37 pm
by Macdoc
But plasma at difference densities is the point.

Energy density is the amount of energy stored in a given system or region of space per unit volume.


So a super hot and super dense plume of plasma surely has a changing energy density "moment by moment" and given there is constant production of energy/heat with thermonuclear reactions I'd say it varies wildly moment by moment.

Team creates high-fidelity images of Sun's atmosphere - Phys.org
https://phys.org › Astronomy & Space › Astronomy
Jul 18, 2018 - Team creates high-fidelity images of Sun's atmosphere. July 18 .... "We should expect steep fluctuations in density, magnetic fluctuations and reconnection ... Explore further: STEREO maps much larger solar atmosphere than .

https://phys.org/news/2018-07-team-high ... phere.html

Air pressure is independent of elevation?

Yes - it can be compressed, and air pressure at sea level changes all the time within bounds.

Hot water does not convect?


Yes but pressure doesn't change significantly the way a gas does and it is entirely temperature dependent - very hard to compress further unlike a gas or a plasma.

That a photon takes a long time "on average" to reach core to surface I don't see as relevant but I'm willing to be illuminated :whistle: