Extended chiral algebras and modular invariant partition functions

A. N. Schellekens*, S. Yankielowicz

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review


We show how the fusion rules can be used to associate with every rational conformal field theory a discrete group, the center. The center is generated by primary fields having unique fusion rules with any other field. The existence of a non-trivial center implies the existence of non-diagonal modular invariants, which are related to extended integer or fractional spin algebras. Applied to Kac-Moodt algebras this method yields all known as well as many new infinite series of modular invariants. Some results on exceptional invariants are also presented, including an example of an exceptional integer spin invariant that does not correspond to a conformal embedding.

Original languageEnglish
Pages (from-to)673-703
Number of pages31
JournalNuclear Physics, Section B
Issue number3
StatePublished - 4 Dec 1989
Externally publishedYes


FundersFunder number
Israel Academy of Science
US-Israel Binational Science Foundation


    Dive into the research topics of 'Extended chiral algebras and modular invariant partition functions'. Together they form a unique fingerprint.

    Cite this