Continuity Equation
In special relativity, the statement of charge conservation is that the Lorentz invariant divergence of J is zero::
where is the 4-gradient. This is the continuity equation.
In general relativity, the continuity equation is written as:
where the semi-colon represents a covariant derivative.
Read more about this topic: Four-current
Famous quotes containing the words continuity and/or equation:
“There is never a beginning, there is never an end, to the inexplicable continuity of this web of God, but always circular power returning into itself.”
—Ralph Waldo Emerson (1803–1882)
“Jail sentences have many functions, but one is surely to send a message about what our society abhors and what it values. This week, the equation was twofold: female infidelity twice as bad as male abuse, the life of a woman half as valuable as that of a man. The killing of the woman taken in adultery has a long history and survives today in many cultures. One of those is our own.”
—Anna Quindlen (b. 1952)