Naked Science Forum
Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: geordief on 06/11/2019 00:46:19
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Is that all the vacuum is?
And are there mediums that have properties that are closer to those of a vacuum than others?
If you "rarify" any medium does it approach a vacuum as a limit?
So a vacuum in that sense is ** a kind of medium ,especially since it is said that it is probably not empty?
** Well at least is not the opposite of a medium
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It's a geometry defined from a inside.
It's also 'SpaceTime'.
But before all it's something we define by being inside it.
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It's a geometry defined from a inside.
I am not sure I follow.In what sense is the vacuum described geometrically?
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Particle fields have potential. The fields, electromagnetic and gravitational for instance, extend to infinity. Potential is converted to energy by a displacement in the location of a mass. Since the fields exist everywhere then this potential also exists everywhere. So the vacuum cannot simply be empty. There is a ground state for each field which is its minimum potential. This represents the minimum or zero point energy of the field.
See also the Wikipedia reference on action.
https://en.m.wikipedia.org/wiki/Action_(physics)#:~:targetText=In%20physics%2C%20action%20is%20an,the%20principle%20of%20stationary%20action.&targetText=Action%20has%20the%20dimensions%20of,SI%20unit%20is%20joule%2Dsecond. (https://en.m.wikipedia.org/wiki/Action_(physics)#:~:targetText=In%20physics%2C%20action%20is%20an,the%20principle%20of%20stationary%20action.&targetText=Action%20has%20the%20dimensions%20of,SI%20unit%20is%20joule%2Dsecond.)