Effective mass (solid-state physics) from both sides gives where is the th element of , is the th element of , and are the th and th elements of , respectively, and is the total energy of the particle according to the Planck–Einstein relation. The index is contracted by the use of Einstein notation (there is an implicit summation over ). Since Newton's second law uses the inertial mass (not the gravitational mass), we can identify the inverse of this mass in the equation above as the tensor This tensor expresses the change in group velocity due to a change in crystal momentum. Its
Gregangelo’s Velocity Circus/Arts and Entertainment physics into the themes and titles of his choreographed performances. Herrera became aware of the Big Bang theory in the 1990s; in 1992 scientists witnessed through a telescope what they thought was a universe coming into existence. Obsessed with the Big Bang theory, Herrera wanted a company name that described the force of everything that exists in the universe. Thus, Herrera thought the equation for velocity (velocity equals distance over time) fit the kinetic nature of circus arts, performance arts, and the arts in general. Finding that art comes into existence through movement is very characteristic of the traditional Whirling