English

Diagonal Limit for Conformal Blocks in d Dimensions

High Energy Physics - Theory 2015-10-30 v3

Abstract

Conformal blocks in any number of dimensions depend on two variables z, zbar. Here we study their restrictions to the special "diagonal" kinematics z = zbar, previously found useful as a starting point for the conformal bootstrap analysis. We show that conformal blocks on the diagonal satisfy ordinary differential equations, third-order for spin zero and fourth-order for the general case. These ODEs determine the blocks uniquely and lead to an efficient numerical evaluation algorithm. For equal external operator dimensions, we find closed-form solutions in terms of finite sums of 3F2 functions.

Keywords

Cite

@article{arxiv.1305.1321,
  title  = {Diagonal Limit for Conformal Blocks in d Dimensions},
  author = {Matthijs Hogervorst and Hugh Osborn and Slava Rychkov},
  journal= {arXiv preprint arXiv:1305.1321},
  year   = {2015}
}

Comments

21 pages; v2: misprints in Eqs. 2.17 and 4.9 corrected; v3: misprints in A.5 and A.6 corrected

R2 v1 2026-06-22T00:12:23.674Z