Operator Mixing and the BMN Correspondence

TL;DR

This paper updates the BMN correspondence analysis by incorporating operator mixing, diagonalizing two-point functions, and comparing anomalous dimensions with string theory energy shifts, revealing unexpected degeneracies and discrepancies.

Contribution

It introduces a detailed treatment of operator mixing in the BMN correspondence and compares field theory and string theory results at order g_2^2 λ'.

Findings

Operators in different R symmetry multiplets remain degenerate at this order.

Discrepancy found between string theory energy shifts and field theory anomalous dimensions.

Operator mixing significantly affects the BMN correspondence analysis.

Abstract

In this note we update the discussion of the BMN correspondence and string interactions in hep-th/0205089 to incorporate the effects of operator mixing. We diagonalize the matrix of two point functions of single and double trace operators, and compute the eigen-operators and their anomalous dimensions to order g_2^2 \lambda'. Surprisingly, operators in different R symmetry multiplets remain degenerate at this order. We also calculate the corresponding energy shifts in string theory, and find a discrepancy with field theory results, indicating possible new effects in light-cone string field theory.