Some researchers have recently suggested by studying the shape of the universe according to the most recent observations, that the possible origin itself has been from a state of zero energy or very close to zero. This seems to be in contradiction with the relativistic energy coming from its mass, m, which determines that its energy is equal to or greater than mc2. However, the hypothesis of dark energy as a negative energy field, in a global energy balance and its enormous weight with respect to dark matter and baryonic mass, could make us think that the total energy of the universe could be zero or very close to zero. In this paper we work with this hypothesis, and the vacuum field is carefully studied by studying a wave function that represents it. This wave function is obtained from a Klein-Gordon type wave equation that is studied here. The excellent results obtained in terms of calculating the vacuum ener-gy density, the vacuum as a physical state with its own mass and there-fore capable of curving space-time, and the introduction of dark energy as an essential element in the universe, make this hypothesis and our vacuum model are more than just one more hypothesis to consider.