Type II string theory and modularity

Igor Kriz, Hisham Sati

Research output: Contribution to journalArticlepeer-review


This paper, in a sense, completes a series of three papers. In the previous two [1],[2], we have explored the possibility of refining the K-theory partition function in type II string theories using elliptic cohomology. In the present paper, we make that more concrete by defining a fully quantized free field theory based on elliptic cohomology of 10-dimensional spacetime. Moreover, we describe a concrete scenario how this is related to compactification of F-theory on an elliptic curve leading to IIA and IIB theories. We propose an interpretation of the elliptic curve in the context of elliptic cohomology. We discuss the possibility of orbifolding of the elliptic curves and derive certain properties of F-theory. We propose a link of this to type IIB modularity, the structure of the topological lagrangian of M-theory, and Witten's index of loop space Dirac operators. The discussion suggests a S1-lift of type IIB and an F-theoretic model for type I obtained by orbifolding that for type IIB.

Original languageEnglish (US)
Pages (from-to)1041-1070
Number of pages30
JournalJournal of High Energy Physics
Issue number8
StatePublished - Aug 1 2005


  • F-Theory
  • M-Theory
  • String Duality
  • Superstrings and Heterotic Strings

ASJC Scopus subject areas

  • Nuclear and High Energy Physics


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