COINCIDENCE EIGHT: Neutron-Proton Mass Differences, or Sometimes it doesn't Pay to be Neutral

alschroeder on March 30, 2014

Sources: Geprge Greenstein's THE SYMBIOTIC UNIVERSE and
Barrow and Tipler's THE COSMIC ANTHROPIC PRINCIPLE
(Chapter 6.6). Here's a good on-line reference on why neutrons
decay in fifteen minutes on their own but stay stable in nuclei at
Neutron Stability in Atomic Nuclei.
I based the last two panels on Barrow and Tipler's work, but it's
worth nothing there is at least one dispute on that.
In The Evidence for Fine-Tuning, Robin Collins argues that even if the neutron
were less massive, there might be a path for two neutrons to covert
into a deuteron (a proton and a neutron) and an electron.
“Since these sorts of conversions appear to be allowed, the only
effects we can immediately deduce that a moderate decrease of the
neutron mass would have are that stars would burn very differently
and that stable nuclei, including hydrogen, would shift towards
having a higher proportion of neutrons than we presently find. I
know of no current well-developed argument, however, that these
effects would inhibit the existence of intelligent life. This is an area
that needs further exploration.”
A good theoretical model of what the universe would be like in such
an instance is lacking. And it would require that such a mass
differential to be a very moderate one–i.e., within prescribed limits.
NEXT: ANTIMATTER ANGST AND ANOMALIES