 Ramification (mathematics)

Ramification is branching in a geometric or algebraic map, detected by multiplicity greater than one. For number fields, ramification of a prime means that some prime ideal occurs with exponent greater than one in the extended prime ideal. For a map of smooth algebraic curves, a local parameter pulls back to a parameter with order greater than one at a ramification point.

In mathematics, "ramification" typically refers to the way a mathematical object behaves as it is extended or generalized, often in the context of field theory or algebraic geometry. The term is used in a few specific contexts, notably in: 1. **Field Theory**: In the context of number fields or function fields, ramification describes the behavior of prime ideals in an extension of fields.