A Hopf bundle over a quantum four-sphere from the symplectic group

Abstract

We construct a quantum version of the SU(2) Hopf bundle $S^7\to S^4$. The quantum sphere $S_q^7$ arises from the symplectic group $S{p}_q(2)$ and a quantum 4-sphere $S_q^4$ is obtained via a suitable self-adjoint idempotent $p$ whose entries generate the algebra $A(S_q^4)$ of polynomial functions over it. This projection determines a deformation of an (anti-)instanton bundle over the classical sphere $S^4$. We compute the fundamental $K$-homology class of $S_q^4$ and pair it with the class of $p$ in the $K$-theory getting the value -1 for the topological charge. There is a right coaction of $S{U}_q(2)$ on $S_q^7$ such that the algebra $A(S_q^7)$ is a non trivial quantum principal bundle over $A(S_q^4)$ with structure quantum group $A(S{U}_q(2))$.

27 pages. Latex. v2 several substantial changes and improvements; to appear in CMP

References in corpus (7)

• Quantum group gauge theory on quantum spaces
• Coalgebra Gauge Theory
• Strong Connections on Quantum Principal Bundles
• Projective module description of the q-monopole
• Noncommutative Instantons on the 4-Sphere from Quantum Groups
• Bijectivity of the canonical map for the noncommutative instanton bundle
• Hopf fibration and monopole connection over the contact quantum spheres

Cited by in corpus (7)

• Hopf Maps, Lowest Landau Level, and Fuzzy Spheres
• Polynomial identities and noncommutative versal torsors
• The Split-Algebras and Non-compact Hopf Maps
• A 4-sphere with non central radius and its instanton sheaf
• Differential and Twistor Geometry of the Quantum Hopf Fibration
• An algebraic framework for noncommutative bundles with homogeneous fibres
• Dirac operator on the quantum fuzzy four-sphere $S_{qF}^4$