TY - JOUR 
A1 - Aldaya Valverde, Víctor
AU - Calixto Molina, Manuel
T1 - Central extensions and quantum physics
Y1 - 2008
UR - http://hdl.handle.net/10317/528
UR - arXiv:hep-th/9903141v2
AB - The unitary implementation of a symmetry group G of a classical system in the
corresponding quantum theory entails unavoidable deformations ˜G of G, namely,
central extensions by the typical phase invariance group U(1). The appearance
of central charges in the corresponding Lie-algebra quantum commutators, as
a consequence of non-trivial responses of the phase of the wave function under
symmetry transformations, lead to a quantum generation of extra degrees of
freedom with regard to the classical counterpart. In particular, symmetries of
the Hall effect, Yang-Mills and conformally invariant classical field theories are
affected when passing to the quantum realm.
KW - Matemática Aplicada
KW - Teoría de campos cuánticos
KW - Teorías Yang-Mills
KW - Teoría cuántica
KW - Simetría de grupo G
LA - eng
ER -