Shortening of primary operators in N-extended SCFT_4 and harmonic-superspace analyticity
L. Andrianopoli, S. Ferrara, E. Sokatchev, B. Zupnik
TL;DR
This work classifies all shortening patterns for composite gauge-invariant conformal primaries in SU(2,2/N) theories using extended harmonic superspace. By exploiting G-analyticity and H-analyticity on SU(N)/U(1)^{N-1} cosets, it constructs and catalogs ultrashort, short, and semishort multiplets for N=2,3,4, linking boundary CFT representations to bulk BPS states in AdS$_5$/CFT$_4$. It shows how multitrace operators in N=4 SYM decompose into short UIR blocks, identifying 1/2-, 1/4-, and 1/8-BPS channels corresponding to multiparticle supergravity states, with implications for non-renormalization theorems and protected conformal dimensions. The analysis provides a unified framework for understanding shortening as arising from harmonic-space subspaces and clarifies the spectrum of Kaluza–Klein towers in AdS backgrounds. Overall, the paper advances precise operator realizations of shortened representations and their AdS/CFT significance in extended supersymmetric theories.
Abstract
We present the analysis of all possible shortenings which occur for composite gauge invariant conformal primary superfields in SU(2,2/N) invariant gauge theories. These primaries have top-spin range N/2 \leq J_{max} < N with J_{max} = J_1 + J_2, (J_1,J_2) being the SL(2,C) quantum numbers of the highest spin component of the superfield. In Harmonic superspace, analytic and chiral superfields give J_{max}= N/2 series while intermediate shortenings correspond to fusion of chiral with analytic in N=2, or analytic with different analytic structures in N=3,4. In the AdS/CFT language shortenings of UIR's correspond to all possible BPS conditions on bulk states. An application of this analysis to multitrace operators, corresponding to multiparticle supergravity states, is spelled out.
