The idea of a false vacuum suggests that the energy state of vacuums in our universe is not actually the most stable state possible. Rather, the universe is currently in a state of metastable vacuum energy and that, through a sufficiently-energetic event or quantum tunnelling, a section of space may decay into a more stable, or "true" vacuum state at any moment. This would lead to the universe's Higgs Field, responsible for giving particles mass, to also shift to a more stable state. With a large enough true vacuum, such a collapse would begin permeating throughout the universe at the speed of light, changing the mass of elementary particles and, by extension, many of the fundamental laws of physics, such as gravity and the electroweak force. The consequences of this could range from near-imperceptible changes in physical constants to the complete gravitational collapse of the universe. As of 2018, observation of interactions between Higgs Bosons and Top quarks have assessed with slightly greater than 2σ confidence that the universe is in a false vacuum state, although this is far from conclusive evidence.