Re: The reality of charge

[Chuck Britton <britton@ODIE.NCSSM.EDU>]

> Localizing a deficiency of something (gravitational field energy is
> negative) is, I suppose, conceptually possible. I wonder what
> gravitational mass density distribution, rho, might appropriately
> be associated with negative gravitational field energy density u ?
>                                                                g
>                                    u
>                                     g
>                             rho = ----
>                                     2
>                                    c
>
> Proper mass is real in my cosmology, by the way, but I know of no
> instances of negative mass. Eh?
>
> Leigh


I just sat through the AAPT's Klopsteg Memorial Lecture delivered by
Michael S. Turner of the U. of Chicago, entitled Cosmology: From
Quantum Fluctuations to the Expanding Universe.

He points out that in GR, the gravitational attraction has its
'source' in rho + 3p, with rho being the usual mass density and p is
the 'pressure' of local space. (His analogy, if space is a stretched
sheet, then its p is negative.)

This overall NEGATIVE gravity source is used to 'explain' the
recently verified ACCELERATION of the expansion of the universe.

I dunno if this is relevant to the current 'discussion' of energy but
it seemed relevant to Leigh's post.

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Chuck Britton                                   Education is what is left when
britton@odie.ncssm.edu                          you have forgotten everything
North Carolina School of Science & Math         you learned in school.
(919) 286-3366  x224                            Albert Einstein,        1936