Precision, while impressive, is a necessary but not sufficient requirement for accuracy. Physical Review Letters , Vol. 24 October 1977, pp. The light beams are considered to be traveling in a vacuum. In the universe, time could flow according to either atomic time or orbital time.
Nuclear reactions convert mass to energy.
Therefore, chemical and nuclear reactions would not change. However, the speed of chemical and nuclear reactions would change, because the vibrational frequencies of atoms and nuclei would change. Also, radioactive decay rates, which depend on the vibrational frequency of the nucleus, would decrease if c decreased. 116, December 1998, pp. This problem for conventional astronomy has been quietly recognized for several decades.