[1][2][3] The field, originally postulated by Alan Guth,[1] provides a mechanism by which a period of rapid expansion from 10−35 to 10−34 seconds after the initial expansion can be generated, forming a universe not inconsistent with observed spatial isotropy and homogeneity.
The basic[clarification needed] model of inflation proceeds in three phases:[4] A "vacuum" or "vacuum state" in quantum field theory is a state of quantum fields which is at locally minimal potential energy.
This state can be seen as a true vacuum, filled with a large number of inflaton particles.
[citation needed] The shape of the potential energy function near "tunnel exit" from false vacuum state must have a shallow slope, otherwise particle production would be confined to the boundary of expanding true vacuum bubble, which contradicts observation (the universe we see around us is not built of huge completely void bubbles).
When complete, the decay of inflaton particles fills the space with hot and dense Big Bang plasma.
Depending on the modeled potential energy density, the inflaton field's ground state might, or might not, be zero.
The term inflaton follows the typical style of other quantum particles’ names – such as photon, gluon, boson, and fermion – deriving from the word inflation.
One of the obstacles for narrowing its properties is that current quantum theory is not able to correctly predict the observed vacuum energy, based on the particle content of a chosen theory (see vacuum catastrophe).