Retuning After Every Transition: Vacuum-Energy Jumps at the Grand-Unification, Electroweak, and QCD Epochs

A cancellation that fixes the vacuum energy density must survive the phase transitions of the early universe, each of which shifts that density by roughly the fourth power of the transition temperature. This paper computes the shifts for the grand-unification, electroweak, and QCD transitions and expresses each as the number of decimal digits by which a prior cancellation would be spoiled, relative to an observed density of 2.52 x 10^-47 GeV^4. The electroweak jump alone requires retuning to 54.6 digits; the QCD jump, the last of the three, still requires 43.3 digits. The final tuning therefore cannot predate a cosmic time of about 4.44 x 10^-5 seconds. The results are computations from stated assumptions, not measurements.