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
Velocity (newspaper) in Louisville, and gay life. Regular weekly features included "The Bar Hopper", in which a local tavern was profiled; "The Party Crasher", a photo-story from the weekend's parties; and "What I'm Into", a mini-profile of a local person. "Velocity" was discontinued during a round of budget cuts by Gannett. Velocity (newspaper) Velocity was a free, weekly newspaper published between December 3, 2003 and June 15, 2011, by "The Courier-Journal" of Louisville, Kentucky. The full-color tabloid was distributed at 1,800 locations in a 13-county area in Kentucky and Southern Indiana. "Velocity" was widely seen as an attempt by the "Courier-Journal" and