The Bosonic Ancestor of Closed and Open Fermionic Strings

TL;DR

This paper demonstrates how ten-dimensional fermionic string theories can be derived from a 26-dimensional bosonic string framework through a consistent truncation process, linking all M-theory strings to the bosonic string.

Contribution

It introduces a truncation method from bosonic to fermionic strings, establishing a unified origin and deriving anomaly-free Chan-Paton groups for various string theories from bosonic considerations.

Findings

Derived fermionic string theories from bosonic string via truncation.

Proved anomaly-free Chan-Paton groups from bosonic string compactification.

Linked M-theory strings and bosonic string within conformal field theory.

Abstract

We review the emergence of the ten-dimensional fermionic closed string theories from subspaces of the Hilbert space of the 26-dimensional bosonic closed string theory compactified on an $E_8\times SO(16)$ lattice. They arise from a consistent truncation procedure which generates space-time fermions out of bosons. This procedure is extended to open string sectors. We prove, from bosonic considerations alone, that truncation of the unique tadpole-free $SO(2^{13})$ bosonic string theory compactified on the above lattice determines the anomaly free Chan-Paton group of the Type I theory. It also yields the Chan-Paton groups making Type O theories tadpole-free. These results establish a link between all M-theory strings and the bosonic string within the framework of conformal field theory. Its significance is discussed.