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Name: Jerome G.
Status: student
Grade: N/A
Location: NJ
Country: N/A
Date: 12/6/2005
Question:
In General Relativity, Einstein cedes that the speed of light is functionally related to mass density. Is it possible that as the universe expands, the speed of light itself is "speeding up"; or, conversely that in the past the speed of light was "slower" and thus the galaxies that we observe today are much further away than we think they are? And that the mathematical contradictions implicit in the "big bang" may be resolvable?

Replies:
There have been speculations about the constancy of the fundamental constants, e.g. the speed of light. In fact, there is a book "Faster than the Speed of Light" by Joao Magueijo (a mainstream theoretical physicist), that specifically addresses the consequences of varying speed of light and/or other "fundamental constants". The debate gets pretty heated, and sometimes personal, but there is nothing scientifically wrong with asking "what if" questions. Speculation is a valid part of the scientific process. Many scientific theories begin as more speculation than ordered logical mathematical constructions. In particular, quantum theory, and the theory of relativity were both considered "speculation" be many contemporary scientists in their early days. Having conceded that, the weight of the scientific data supports the constancy of the fundamental constants such as the speed of light, the fine structure constant, the charge on the electron etc.

There are 5 "fundamental constants that are absolutely necessary: the speed of light, the gravitational constant, Planck's constant / 2pi, Coulomb force constant, and Boltzman's constant:

See http://en.wikipedia.org/wiki/Planck_units

But lest you think that there is total agreement about what and how many 'fundamental' constants there are see:

http://xxx.lanl.gov/abs/physics/0110060

or do a "Google" search on the term "minimal set fundamental constants",

and enjoy the discussions.

Vince Calder


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