Constraints on 2d CFT partition functions

Daniel Friedan, Christoph A. Keller

Research output: Contribution to journalArticlepeer-review

71 Scopus citations


Modular invariance is known to constrain the spectrum of 2d conformal field theories. We investigate this constraint systematically, using the linear functional method to put new improved upper bounds on the lowest gap in the spectrum. We also consider generalized partition functions of N = (2, 2) superconformal theories and discuss the application of our results to Calabi-Yau compactifications. For Calabi-Yau threefolds with no enhanced symmetry we find that there must always be non-BPS primary states of weight 0.6 or less.

Original languageEnglish (US)
Article number180
JournalJournal of High Energy Physics
Issue number10
StatePublished - Oct 2013


  • Conformal and W Symmetry
  • Field Theories in Lower Dimensions
  • Sigma Models

ASJC Scopus subject areas

  • Nuclear and High Energy Physics


Dive into the research topics of 'Constraints on 2d CFT partition functions'. Together they form a unique fingerprint.

Cite this