1999/10/31 by N. A. Obers, Niels A Obers, Boris Pioline +1 · 1 citation
Mathematics · Physics and Astronomy · #Advanced Algebra and Geometry #Algebraic structures and combinatorial models #Black Holes and Theoretical Physics #hep-th
paper · pdf · doi:10.1088/0264-9381/17/5/330
published as Class.Quant.Grav.17:1215-1224,2000 · 11 pages, Latex, submitted to Proceedings of Strings '99, published version
openalex publication_date 2000/02/23 · arxiv created 2000/03/01 · arxiv updated 2011/04/15 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/30
We discuss the relevance of Eisenstein series for representing certain G ( )-invariant string theory amplitudes which receive corrections from BPS states only. The Eisenstein series are constructed using G ( )-invariant mass formulae and are manifestly invariant modular functions on the symmetric space K G ( ) of non-compact type, with K the maximal compact subgroup of G ( ). In particular, we show how Eisenstein series of the T-duality group SO ( d , d , ) can be used to represent one- and g -loop amplitudes in compactified string theory. We also obtain their non-perturbative extensions in terms of the Eisenstein series of the U-duality group E d +1( d +1) ( ).