A novel large-N reduction on S3: Demonstration in Chern-Simons theory

We show that the planar Chern-Simons (CS) theory on S3 can be described by its dimensionally reduced model. This description of CS theory can be regarded as a novel large-N reduction for gauge theories on S3. We find that if one expands the reduced model around a particular background consisting of multiple fuzzy spheres, the reduced model becomes equivalent to CS theory on S3 in the planar limit. In fact, we show that the free energy and the vacuum expectation value of unknot Wilson loop in CS theory are reproduced by the reduced model in the large-N limit.