Lightcone expansions of conformal blocks in closed form

Abstract

We present new closed-form expressions for 4-point scalar conformal blocks in the s- and t-channel lightcone expansions. Our formulae apply to intermediate operators of arbitrary spin in general dimensions. For physical spin $\ell$, they are composed of at most $(\ell +1)$ Gaussian hypergeometric functions at each order.

17 pages, v2, published version, Appendix B added, typos corrected