The expanding universe is based on the largely unspoken premise that electrical charge is a universal constant. However, as far as I know, that is an unverified assumption.
I have a web based article that, in addition to summarizing the major themes regarding missing mass, provides an alternate model for explaining cosmological redshifts wtih variations in electrical charge. The variable charge model is in parts 5 and 6 of the article.
Please see:
Cosmology's Missing Mass Problems
http://www.datasync.com/~rsf1/missmass.htm
An associated, earlier, article on the topic is:
Cosmological Redshift
http://www.datasync.com/~rsf1/cosmo_rs.htm
If the variable charge model holds water then the whole universe will be comprised strictly of the Milky Way galaxy. Other "galaxies" will revert to their early 1900's
status as local "spiral nebulae."
Bob Fritzius