2025-11-15   60496

Lifting Elements from a Lie Group to its Universal Covering Group

A connected Lie group G has a universal covering group G̃. The covering homomorphism σ:G̃→ G is typically not one-to-one. A map from G back into G̃ is called a lift if its composition with σ is the identity map on G. If σ is not one-to-one, then a lift cannot be continuous everywhere, but any continuous path γ in G can be lifted to a continuous path γ̃ in G̃ with σ(γ̃)=γ. This article introduces a special lift and applies it to the idea of lifting a practically continuous path (sequence of closely-spaced points) in G to a practically continuous path in G̃. Article 40191 uses this to define Wilson operators associated with representations of the covering group G̃ of the gauged group G.

Download PDF (22 pages, 841 KB)

Revision history


www.cphysics.org updated 2025-11-15