Editing Differential geometry (section)

=== Gauge theory ===
{{Main article|Gauge theory (mathematics)}}

Gauge theory is the study of connections on vector bundles and principal bundles, and arises out of problems in [[mathematical physics]] and physical [[gauge theory|gauge theories]] which underpin the [[standard model of particle physics]]. Gauge theory is concerned with the study of differential equations for connections on bundles, and the resulting geometric [[moduli space]]s of solutions to these equations as well as the invariants that may be derived from them. These equations often arise as the [[Euler–Lagrange equations]] describing the equations of motion of certain physical systems in [[quantum field theory]], and so their study is of considerable interest in physics.