Transdimensional defects

A bstract This note introduces a novel paradigm for conformal defects with continuously adjustable dimensions. Just as the standard ε expansion interpolates between integer spacetime dimensions, a new parameter, δ , is used to interpolate between different integer-dimensional defects. This framework is explored in detail for defects of dimension p = 2 + δ in both free and interacting O ( N ) bulk conformal field theories (CFTs) in d = 4 – ε . Comprehensive calculations are performed to first and second order in ε and to high or all orders in δ . Additionally, in the large- N limit, the interpolation between defects of dimensions p = 1 and p = 2 is analysed for spacetime dimensions 4 ⩽ d ⩽ 6. The new parameter δ provides a natural enrichment of the space of defect CFTs and allows to find new integer dimension or co-dimension defects.