In 1907 using special relativity, Albert Einstein proved that vacuum permittivity, ε, changes in accelerating coordinate reference frames. ε is the scalar in Maxwell’s equations that determines the speed of light and the strength of electrical fields. In 1952, Møller confirmed Einstein’s discovery by proving that ε is a function of the curvature of static spacetimes. In 1994, Sumner proved that ε changes with the curvature of Friedmann spacetime. Photon energies are proportional to ε, but the energies of photons emitted by atoms are proportional to ε^2. This difference reverses the interpretation of Hubble redshifts. Hubble redshifts only result when a Friedmann universe is collapsing. This is confirmed by the Pantheon redshift data fit of 1048 supernovas with a negative Hubble constant Ho =-72.10±0.75 km s−1 Mpc−1 and a deceleration parameter 1/2 < q_o < 0.51. The velocity of light in Friedmann geometry is inversely proportional to the radius of the universe. The velocity of light was infinite at the Big Bang and decreased to zero at maximum size when the universe began to collapse. The velocity of light is now accelerating towards infinity. Its current value is c. Collapse will be complete in 9.05 billion years. The current age of the universe is estimated to be 1.54 x 10^4 billion years.