Higgs bosons obey the conservation of energy law, which states that no energy is created or destroyed, but instead can be transferred or change form. First, the energy starts out in the gauge boson that interacts with the Higgs field. This energy is in the form of kinetic energy as movement. After the gauge boson interacts with the Higgs field, it slows down. This slowing down reduces the amount of kinetic energy in the gauge boson. However, this energy is not destroyed. Instead, the energy from the motion goes into the field and is converted into mass-energy, which is the energy stored in mass. The mass created can become what we call a Higgs boson. The amount of mass created comes from Einstein's famous equation E=mc, which states that mass is equal to a large amount of energy (for example, 1 kg of mass is equivalent to almost 90 quadrillion joules of energy—the same amount of energy used by the entire world in roughly an hour and a quarter in 2008). Since the amount of mass-energy created by the Higgs field is equal to the amount of kinetic energy that the gauge boson lost by slowing down, energy is conserved.