Time Shift Between Wormhole Mouths and the Chronology Threshold

Moving one mouth of a wormhole pair makes the mouths age at different rates, so the throat connects two moments as well as two places. A mouth carried at one tenth of light speed for one year returns with a time shift of 1.83 days relative to its twin; at half of light speed the shift is 48.9 days, and even at one hundredth of light speed it is 1.58e+03 seconds. A closed timelike curve forms when the shift exceeds the external light-travel time between the mouths: 499.0 seconds at one astronomical unit, but only 3.34e-03 seconds at a thousand kilometres. The verdict has two halves. Constructing the shift is arithmetically easy, far easier than building the throat. Using it is where physics objects, through the chronology-protection mechanism in which vacuum fluctuations amplify without bound as the threshold is approached. Computed, not measured.