Figure 26-11: Inflation: Transitioning from the False Vacuum to the True Vacuum (a) The energy of the vacuum is thought to be determined by the value of a quantity called the inflaton field. As shown by the red curve in this diagram, this energy is at a minimum for a certain value of this field. The state of lowest energy is called the true vacuum. (b) Inflation is associated with the universe making a transition from its initial false-vacuum state to a true-vacuum state. This expansion took place over a period of about 10−32 seconds, during which the universe cooled to a temperature of about 3 K. (c) As the universe “settled in” to the true vacuum state, energy was released that reheated the universe to a temperature of 1027 K.