Re: values of fundamental constants

Kevin O'Brien (Cuchulaine@worldnet.att.net)
Tue, 3 Nov 1998 21:39:03 -0700

Greetings Stan:

"Recently you claimed in one of your posts that: 1. There is preliminary
evidence that the fundamental constants of nature have changed over
time;..."

I hope I wasn't that dogmatic, but I probably was. In the November 1998
issue of _Scientific American_ there is a news item in the Science and the
Citizen section (page 24) entitled "Inconstant Constants." Here is an
excerpt:

"Of all of the assumptions that undergird modern science, perhaps the most
fundamental is the uniformity of nature....Until now. A team of astronomers
led by John K. Webb of the University of New South Wales has found the first
hint that the laws of physics were slightly different billions of years ago.
'The evidence is a little flimsy,' says Robert J. Scherrer of Ohio State
University. 'But if it's confirmed, it'll be the most startling discovery
of the past 50 years.'"

Basically, these researchers looked for variations in the fine-structure
constant, which is the ratio of electromagnetic energy to the energy
inherent in mass. If it varied as much as by a factor of 10, carbon atoms
(for example) would not be stable enough to form organic molecules. One
piece of evidence in support of its constancy is the naturally occurring
Oklo nuclear reactor. Alexander I. Shlyakhter looked at the composition of
the nuclear waste build-up and concluded that 2 billion years ago (the time
of the reaction) the constant was identical to its present value, within a
few parts in 10 million.

The astronomers, however, looked at the spectral lines in quasar light
produced as that light passed through intergalactic gas clouds. If the
constant had changed, the observed lines should be different from what they
are in the lab. Their observations indicated that the constant has not
changed in the last seven billion years, but observations of more distant
clouds indicate that the constant was smaller by two parts in 100,000.
According to the astronomers, no known experimental error can mimic the
effect.

Naturally there is skepticism. Relativicists believe that general
relativity can accomodate slight shifts in the fine-structure constant due
to the expanding universe. String theorists claim that the constant really
isn't constant at all. (In string theory, also known as hyperspace theory,
the cosmos is multi-dimensional, and what we perceive as natural forces --
like electromagnetism -- are really other spatial dimensions. If these
dimensions changed in size, so would the constants.) However, both theories
predict a much smaller and more uniform change than observed. Other
speculations suggest the sudden decay of some unknown form of dark matter or
"shenanigans" of undetected gossamer particles.

Even so, Scherrer is already predicting that changes in the constant should
up in the cosmic microwave background radiation. This method is less
sensitive than the spectral line method, but it can look deeper back into
time. The Microwave Anisotropy Probe satellite should be able to pick up
any variations greater than 1%. Others have suggested putting atomic clocks
in spacecraft and sending them towards the sun. The sun's gravity should
amplify any variation in the constant, which would shift the frequency of
radiation emitted by the atoms on which the clocks are based. Subsequently,
each clock based on a different atom should keep different times.

"...2. That before the four fundamental forces of nature were 'decoupled',
the fundamental constants 'could have been changing constantly and wildly'."

Note that in this case I did at least say "could". This is sheer
speculation on my part. Since no one really knows what happened during the
Planck Era, however, it is no more wrong than other speculations.

"Would Glenn, Brian, and David Bowman care to comment about these issues?"

David Bowman? THE David Bowman?!? The Star Child from _2001: Space
Odyssey_? If he doesn't know the truth, no one does. ;-)

Kevin L. O'Brien