A quantity which rigorously assumes the value of zero is said to be identically zero. The "identically" is used for emphasis when simply stating that a quantity is (or appears to be) zero is not considered sufficiently strong. A quantity that is identically zero is said to be vanishing, or sometimes (again for emphasis) to vanish identically.
See alsoAlmost Zero, Hidden Zero, Vanish Identically, Vanishing, Zero
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Cite this as:
Weisstein, Eric W. "Identically Zero." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/IdenticallyZero.html