AMA | October 2024

12348.402 - 12369.5 Sean Carroll

There needs to be a minimum amount of energy in your quantum field theory. There needs to be, in other words, a vacuum state, a state for which the total energy is the minimum possible value. The reason for that is more or less an empirical one. If that weren't true, if you could get arbitrarily large energies, negative energies, then you would get arbitrarily large negative energies.